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Review of fast pyrolysis of biomass and product upgrading

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... Bio-oil yields are maximized at a shorter residence time or lower heating rate. According to Bridgwater (2012), a temperature of approximately 400°C with a residence time of hours to days, provides conditions to produce 35% biochar, 30% liquid, and 35% gaseous products, by weight. ...
... Raw bio-oil quality as fuel is incompatible with conventional fuel because of its high oxygen content. To be used as biofuel, in place of diesel or gasoline, bio-oil must be deoxygenized and refined; many methods exist, including integrated catalytic pyrolysis, decoupled hydrotreating, zeolite vapor cracking, esterification, and gasification to syngas followed by refining (Bridgwater, 2012). Some of these processes result in a loss of yield: an upgrading efficiency of 80% was assumed for this study, based on Bridgwater (2012). ...
... To be used as biofuel, in place of diesel or gasoline, bio-oil must be deoxygenized and refined; many methods exist, including integrated catalytic pyrolysis, decoupled hydrotreating, zeolite vapor cracking, esterification, and gasification to syngas followed by refining (Bridgwater, 2012). Some of these processes result in a loss of yield: an upgrading efficiency of 80% was assumed for this study, based on Bridgwater (2012). ...
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Largely due to manure management, intensive livestock production is known to negatively impact air, water, and soil quality. Excessive manure is often applied to soil as fertilizer or stored in lagoon. However, some thermo-chemical methods, such as gasification and pyrolysis, can transform manure from waste into a valuable resource. The closed-loop dairy concept employs these methods to create biochar derived from cow manure for use as a soil amendment and a water filtration medium. This closed-loop concept has the potential to produce syngas and bio-oil for production of electricity, and to reduce excessive nutrients in liquid manure irrigation by filtering manure slurry stored in lagoons. It replaces solid manure with biochar in land applications to further reduce nutrient runoff and increase soil resilience against erosion. In this study, a Water-Energy-Food-Waste nexus-based analysis and resource allocation tool was developed to evaluate the economic, environmental, and social feasibility of the closed-loop dairy system. The tool utilizes several levers to simulate a user-specified dairy operation, such as number of livestock, acres farmed, quantity of effluent irrigation, distribution of manure and biochar products, and type of biomass conversions. Financial estimates from central Texas in 2018 were used to evaluate the profitability of these practices against the costs of a dairy and hay operation. The study showed that the closed-loop dairy system, while case dependent, could be profitable and, based on operational costs, a small dairy of approximately 200 cows could break even. Results also indicate that the benefits of biomass conversions to produce energy byproducts should increase with scale. This study can help many dairy farms that are considering the economic and environmental sustainability of the industry, which has been under scrutiny.
... Bio-oil (or pyrolysis oil) can be directly produced from biomass via fast pyrolysis [1]. Nevertheless, low-quality bio-oil caused by high contents of oxygen and water makes it incompatible with petroleum-derived hydrocarbon fractions [2], while its low heating value, high viscosity, and corrosiveness limit its application as a source of renewable energy and chemicals [3]. Therefore, bio-oil requires upgrading in order to improve its fuel quality. ...
... Ni-P/γ-Al 2 O 3 was synthesized via incipient wetness impregnation of Ni/γ-Al 2 O 3 with an aqueous solution of a mixture of ammonium phosphates obtained through neutralization of H 3 PO 4 by NH 3 water solution to pH 7 at room temperature with the appropriate phosphorus concentration to have a phosphorus loading of 1 wt.%. The same drying and calcination procedures were used. ...
Article
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Biomass-derived liquids, such as bio-oil obtained by fast pyrolysis, can be a valuable source of fuels and chemicals. However, these liquids have high oxygen and water content, needing further upgrading typically involving hydrotreating using H 2 at high pressure and temperature. The harsh reaction conditions and use of expensive H 2 have hindered the progress of this technology and led to the search for alternative processes. In this work, hydrogenation in aqueous phase is investigated using in-situ produced hydrogen from reforming of glycerol, a low-value by-product from biodiesel production, over Ni-based catalysts. Guaiacol was selected as a bio-oil model compound and high conversion (95%) to phenol and aromatic ring hydrogenation products was obtained over Ni/γ-Al 2 O 3 at 250 • C and 2-h reaction time. Seventy percent selectivity to cyclohexanol and cyclohexanone was achieved at this condition. Hydrogenation capacity of P and Mo modified Ni/γ-Al 2 O 3 was inhibited because more hydrogen undergoes methanation, while Cu showed a good performance in suppressing methane formation. These results demonstrate the feasibility of coupling aqueous phase reforming of glycerol with bio-oil hydrogenation, enabling the reaction to be carried out at lower temperatures and pressures and without the need for molecular H 2 .
... Flash pyrolysis is the most feasible way to measure the kinetic data at isothermal condition [39]. In the reaction process of flash pyrolysis, biomass particles are rapidly decomposed at a very high heating rate (> 1000 K/s), with thousands of reactions occurring in a very few seconds through multiple phases [121]. Therefore, it is a great challenge to experimentally measure the kinetic data (e.g., reaction rates, etc.) of biomass pyrolysis at isothermal conditions. ...
... The key to realize the isothermal reactions is to bring the biomass particles up to the reaction temperature as soon as possible. Thus, various factors (e.g., residence times of volatiles, hydrodynamics of reactors, mass and heat transfer, fast characterization, etc.) must be taken into consideration to meet the requirements of isothermal reactions [121]. ...
Article
Biomass pyrolysis has arisen great attention for producing clean fuels, valuable chemicals, and advanced materials. Knowledge on the properties of both final products and intermediates is crucial to establish better kinetic models for the prediction of products distribution or to control the pyrolysis processes. However, the current mechanism of biomass pyrolysis is far from a full and comprehensive description due to the lack of information on reaction process (e.g., the kinetics of isothermal pyrolysis, dynamics of volatiles formation, the role of reaction intermediates, etc.). Advances in online mass spectrometry equipped with “soft” ionization methods (e.g., photoionization, etc.) and its applications in recent decades exhibit its advantage in exploring the reaction process of biomass pyrolysis, which is hardly achieved by off-line analysis methods. This review systematically discusses the mass spectrometric studies on process analysis of biomass pyrolysis, mainly including: (1) why the process analysis is necessary; (2) how to achieve it by mass spectrometry (MS); and (3) what are the typical works on it. Process analysis will be a key to open the door to reaction chemistry of biomass pyrolysis, but more advanced pyrolysis reactors and analytic techniques must be developed to meet the requirement of process analysis.
... The operating condition of the pyrolysis process can be decided based on the desired product. For instance, slow pyrolysis occurs at lower temperatures with long residence time whilst fast pyrolysis is conducted at higher heating rate and very short residence time and producing higher char and bio-oil yield, respectively [68,69]. The produced bio-oil from pyrolysis process can offset fossil fuel or diesel use in furnaces, boilers, turbines and engines used for power generation purposes. ...
... Furthermore, the pH of the poultry litter derived bio-oil was approximately 6, whilst the reported pH value for turkey litter and hardwood were 4.2 and 2.7, respectively. It was clearly evident that the poultry litter derived biocrude oil has much higher pH than typical biooils [69]. The HHV of the poultry litter derived biocrude oils was in the range of 26 MJ/kg to 29 MJ/kg compared to the bedding material 24 MJ/kg. ...
Article
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Purpose With its substantial CO 2 eq emissions, the agricultural sector is a significant greenhouse gas (GHG) emitter. Animal manure alone contributes 16% of the total agricultural emissions. With a rapidly increasing demand for animal-based protein, animal wastes are expected to rise if sustainable manure management practices are not implemented. Manures have the potential to be treated to generate valuable products (biofertiliser and biocrude) or feedstock for energy production. Thermochemical conversion technologies such as pyrolysis, combustion, supercritical gasification (SCWG), etc., have demonstrated their potential in manure management and valorisation. This study provides a broader overview of these technologies and envisages future manure valorisation trends. Methods The paper presents a state-of-the-art review of manure valorisation. Characterisation of manure, modelling and optimisation of thermochemical conversion technologies along with life cycle anaalysis (LCA) are also reviewed. Results The literature review highlighted that the thermochemical conversion technologies can generate bio-oils, syngas, H 2 , biofuels, heat, and biochar as carbon-free fertiliser. The reported calorific value of the produced bio-oil was in the range of 26 MJ/kg to 32 MJ/kg. However, thermochemical conversion technologies are yet to be commercialised. The major challenges associated with the scale-up of manure derived feedstocks are relatively high moisture and ash content, lower calorific value and higher concentration of impurities (N, Cl, and S). LCA studies conclude that gasification presents a sustainable option for manure valorisation as it is economical with modest environmental threats. Significance of Study This review briefly states the current challenges faced in manure management and presents the case for a sustainable valorisation of animal manures using thermochemical technologies. The economic, environmental and societal advantages of these technologies are presented in order to promote the scientific and industrial development of the subject in the academic and research community. Conclusions Thermochemical conversion technologies are promising for manure valorisation for energy and nutrient recovery. However, their commercialisation viability needs wide-ranging evaluations such as techno-economics, life-cycle analysis, technology take-up and identification of stakeholders. There should be clear-cut policies to support such technologies. It should be advocated amongst communities and industries, which necessitates marketing by the governments to secure a clean energy future for the planet. Graphical Abstract
... They generated more residual solid matter (Table 3) than HydroRef as the quantity of ash increased for the burning system, further supporting incomplete combustion. The occurrence of black carbon (char), soot, or tar in the boiler reduces technical performance and lifespan [58]. It promotes cooler zones within the furnace and corrodes exchanging surfaces. ...
... HydroMask#1 and HydroMask#3 also developed lower flammability and ignitability. Therefore, they would offer product-level solutions for controlling smoky combustion, toxic emission, and hazardous self-heating during transportation and storage [58]. ...
Article
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Incineration and landfilling offer possibilities for addressing high-rate management of COVID-waste streams. However, they can be costly and environmentally unsustainable. In addition, they do not allow to convert them to fuels and chemicals as waste-to-energy and waste-to-product technologies. Therefore, we analyzed whether integrating hydrothermal carbonization (HTC) and pelletization can allow converting the surgical face mask (SFM) and biomass to composite plastic-fiber fuel (CPFF). We blended the plastic material and corncob, peanut shell, or sugarcane bagasse at the proportion of 50:50 (%, dry mass basis) for HTC. We performed the thermal pretreatment of blends in an autoclaving reactor at 180 °C and 1.5 MPa. Then we pelletized the hydrochars in a presser machine at 200 MPa and 125 °C. By analyzing the evidence from our study, we recognized the viability of combining the SFM and agricultural residues for CPFF from comparable technical features of our products to standards for premium-grade wood pellets. For instance, the elemental composition of their low-meltable ash was not stoichiometrically sufficient to severely produce slagging and fouling in the equipment for thermal conversion. Although they contained synthetic polymers in their structures, such as polyethylene from filter layers and nylon from the earloop, they emitted CO and NOx below the critical limits of 200 and 500 mg m-3, respectively, for occupational safety. Therefore, we extended the knowledge on waste-to-energy pathways to transform SFM into high-quality hybrid fuel by carbonization and pelletization. Our framework can provide stakeholders opportunities to address plastic and biogenic waste in the context of a circular economy. Supplementary information: The online version contains supplementary material available at 10.1007/s13399-022-03285-4.
... Longer residence times and high temperatures increase biomass conversion to gas. Pyrolysis conditions can be varied depending on the desired product type (Bridgwater 2012;Dhyani and Bhaskar 2017). Several different modes of biomass pyrolysis depending on conditions, such as heating rate and residence time of biomass, are being actively developed (Hu and Gholizadeh 2019; Kiliç et al. 2014;Adelawon et al. 2021;Dhyani and Bhaskar 2017). ...
Chapter
In this chapter, a brief introduction to various pyrolysis processes and a detailed analysis of fast pyrolysis has been explored. A wide variety of feedstocks suitable for the fast pyrolysis process and physicochemical properties of bio-oil has been incorporated. Various types of pyrolyzers that are available in the papers are also mentioned here. Furthermore, enrichment of bio-oil using various upgradation techniques and its physicochemical properties are also discussed. This includes the processes such as steam reforming, catalytic cracking, and supercritical extraction. The application of bio-oil as a fuel requires enhancement in its properties which is achieved using blending with other fuels. Thus, this chapter also strives to explain the recent advances made in bio-oil properties enhancement. Also, a brief analysis of the techno-economic feasibility of bio-oil production and its environmental sustainability is specified. This chapter attempts to give an overview of the whole concept of bio-oil production to its application.KeywordsPyrolysisBio-oilFast pyrolysis reactor (pyrolyzer)Upgradation and enhancement of bio-oilTechno-economicsEnvironmental sustainability
... However, the scaling up and commercialization of fast pyrolysis of biomass are still restricted due to the heat transfer bottleneck issue [4]. As is known, the pyrolysis process is an endothermic process, external heat is required to sustain the reactions to take place at an elevated temperature [5,6]. ...
Article
Pyrolysis of wheat straw in Li2CO3-K2CO3 binary salt was conducted in a fixed-bed reactor, the char structure evolution under different pyrolysis temperatures was analyzed. The results showed that the biochar yield decreased with temperature increasing, the addition of Li2CO3-K2CO3 salt enhanced heat transfer and promoted charring reactions to form more char. At 450–550 °C, the changes in biochar structure from molten salt pyrolysis showed similar trend with those from conventional pyrolysis, the C content increased and the H and O contents decreased, the aromatization degree of biochar increased, the surface functionalities on char surface all decreased. At 600–700 °C, the effect of temperature on biochar structure from molten salt pyrolysis showed significantly different trend. The increase of temperature further decreased H content, but increased O content and decreased C content, the molar ratio of H/C decreased while that of O/C increased. The etching of K salt consumed more C and retained more O in char structure, thus caused insignificant increase in aromatization level of biochar and retaining more CO/COC and –OH functionalities. More porous structures were formed due to the enhanced activation effect of molten salt at higher temperature. The BET surface area of 700MBC could achieve 568.20 m²/g. A functionalized mesoporous biochar with enriched O-containing groups was thus obtained from molten salt pyrolysis of biomass.
... Longer residence times and high temperatures increase biomass conversion to gas. Pyrolysis conditions can be varied depending on the desired product type (Bridgwater 2012;Dhyani and Bhaskar 2017). Several different modes of biomass pyrolysis depending on conditions, such as heating rate and residence time of biomass, are being actively developed (Hu and Gholizadeh 2019; Kiliç et al. 2014;Adelawon et al. 2021;Dhyani and Bhaskar 2017). ...
Chapter
Plant biomass is an excellent lignocellulosic source that can produce renewable and environment-friendly biofuels. However, the natural physiochemical structure of plant lignocellulose has strong recalcitrance and heterogeneity, which results in low yields of biofuels, limiting its effective valorization in biorefineries. This rigidity of lignocellulose presents economic and technical challenges in biomass conversion processes. Various pretreatment methods are used separately and in combination to resolve this. Pretreatment methods change the structure and chemical composition of the plant biomass, which makes it more accessible to the conversion systems for biofuel production. This chapter will discuss the physical and chemical basis of lignocellulose recalcitrance and the biomass components contributing to it. This chapter will also explain the role of pretreatment strategies in biorefineries and their influence on the structure and composition of lignocellulosic biomass. The fundamental understanding of biomass recalcitrance and the role of pretreatment methods can aid in the efficient utilization of lignocellulosic biomass in biorefineries and the development of future pretreatment methodologies.KeywordsLignocelluloseRecalcitrancePretreatmentBiorefinery
... Longer residence times and high temperatures increase biomass conversion to gas. Pyrolysis conditions can be varied depending on the desired product type (Bridgwater 2012;Dhyani and Bhaskar 2017). Several different modes of biomass pyrolysis depending on conditions, such as heating rate and residence time of biomass, are being actively developed (Hu and Gholizadeh 2019; Kiliç et al. 2014;Adelawon et al. 2021;Dhyani and Bhaskar 2017). ...
Chapter
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The potential of renewable energy and chemical sources is more important than ever before due to the combination of diminishing crude oil supplies and population increase. The bio-refinery concept is evolving from a fascinating notion to a viable replacement for a variety of fossil-fuel-based goods. Pre-treatment processes designed for a comprehensive bio-refinery shall show selective dissociation of each constituent of a biomass feedstock, ease of access to and detachment of the constituents after separation, high yield revival of every component, process components readily available for conversion into chemicals with negligible purification, as well as economic feasibility. These criteria are typically met by organosolv pre-treatments. To be broadly accepted by markets and the public, the generation of renewable chemicals, as well as biofuels, should be price and performance competitive employing crude oil-derived counterparts. The focus of this study is on developing a biomass conversion technique that maximizes the transformation of lignocellulosic biomass into commercially viable high-value products, allowing for effective translation to an economically feasible commercial process.KeywordsBio-refineryBiomass feedstockEconomyOrganosolv technologyHigh-value products
... One of the promising thermal technologies promoting the conversion of the feedstocks from waste to energy is pyrolysis. Today, many types of fast (Bridgwater 2012), intermediate (Funke et al. 2017), and slow (Cong et al. 2018) pyrolysis reactors have been developed. Recently, Yang et al. (2021) reported that intermediate pyrolysis may be an alternative to fast and slow pyrolysis. ...
Article
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Biomass waste contains an abundant source of energy that can be transformed into high-calorific fuel during intermediate pyrolysis, consequently reducing the use of fossil fuel resources. In the present study, medium density fibreboard (MDF), brewery spent grains (BSG) and post-extraction soybean meal (SM) were used to pyrolysis. Valorisation of these wastes via intermediate pyrolysis was carried out at a temperature of 773 K in a fixed-bed reactor under nitrogen atmosphere. The ultimate analysis showed that MDF char has offered the highest carbon content. Generally, chars obtained from these feedstocks were characterized by different internal microstructures. On the one hand, the surface of MDF char has exhibited pores with a regular pattern of small perpendicular blocks. On the other hand, irregular open spaces were detected in BSG and SM chars. The results of this investigation of the microstructure proved that the studied biomass wastes are perspective feedstocks to obtain high-value bioenergy products. Based on the enthalpy balance, it was concluded that the heating value of the pyrolysis gas was higher, the more endothermic pyrolysis process. The research hypothesis confirms that the higher the K2O/CaO ratio in the ash, the better biomass pyrolysis process was catalysed and as a result, less additional heat was required for pyrolysis. To carry out the pyrolysis of MDF, SM and BSG, additional heat input was required in the amount of 2016.8, 1467.9 and 881.1 kJ, respectively. It was found that 4–10% of the higher heating value of the raw materials was missing to achieve the self-sustaining energy of intermediate pyrolysis. Graphical abstract
... Pirolisis merupakan proses dekomposisi material dalam reaktor dengan menggunakan panas tanpa melibatkan oksigen dalam prosesnya (Bridgwater, 2012). Melalui dekomposisi material dalam proses pirolisis akan dihasilkan cairan (Roy & Dias, 2017). ...
Article
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Solid waste from oil palm plantations and industries generally contains high organic matter so that it is environmentally possible. The pyrolysis technique is currently an effective technology in the handling of palm oil waste because in the process a biochar product is produced, immediately liquid which has high heat and can be used in agriculture. Generally, pyrolysis equipment has a large size with a large capacity. In addition, controlled pyrolysis is usually found in pilot-scale or relatively large dimensions for industrial-scale that have been assembled so that they are not easy to carry and move. The purpose of this study is to design a portable pyrolysis equipment that is easy to use and move to handle palm oil solid waste. The stages of the research carried out were the manufacture of a pyrolysis device and the testing stage of the tool. Testing the pyrolysis tool using raw material from palm oil midrib-leaf waste. Tool testing is carried out to determine whether the tool works well, to determine the yield (%) produced and the working capacity of the tool (Kg/Hour). The results of this study are the stages of the process of making a portable pyrolysis tool including making reactors, making condensers, installation processes and automation of tools with control panels, making tool tables, and assembling tools. The test results show the yield of the tool is 39,1% and the working capacity of the tool is 0,24 kg/hour.
... Biochar is mainly produced from the by-products of plant parts (Preston and Schmidt 2006;Knicker 2007) by combustion processes (Bridgwater 2012) and is used as a soil supplement for carbon sequestration and increasing soil fertility in damaged soils (Steiner et al. 2007). Organic matter in the soil is essential for preserving the soil's physical, chemical, and biological integrity, as well as its ability to fulfill agricultural and environmental tasks (Izaurralde et al. 2001;Srinivasarao et al. 2012). ...
Article
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To combat the adverse climatic condition in agriculture, a sustainable production system like organic agriculture is inseparable, which stimulates and increases agro-ecosystem health, including biodiversity, biological cycles, and soil biological activity. Throughout this context, this study examined the current literature on organic agriculture's contribution to food and water security, as well as its expansion in South Asia. Relevant research documents were retrieved using Elsevier's Scopus database and other sources in order to do this (by applying search equations). The authors have accordingly underlined the huge scope and opportunity of organic agriculture that can contribute to ecological sustainability, especially in the developing countries of South Asia and other regions. Our assessment found that six case studies of organic agriculture have potentiality that could boost the production of quality food, proper utilization of renewable resources, maintaining long-term soil fertility, biological pest control, and efficient use of water resources. This review discussed the organic agricultural practices that secure the food and water status from a South Asian perspective.
... Table 1 shows the proximate analysis of the Avocado peel. Avocado peel has a moisture content (5.63 %) that is comparable with, and lesser than, that of coal which is 11 % (Mckendry, 2002) but lesser than that of the Avocado seeds (7.2 %) and pulp (9.05 %) of the same fruit as presented in table 1. Feedstock with high of low quality bio-oil upon pyrolysis (Bridgewater, 2012) and high moisture content also lowers the energy content and also creates ignition difficulty for solid fuel. Hence the moisture content of the Avocado peel shows a good prospect as solid fuel. ...
Article
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The thermal decomposition and kinetic behavior of Avocado peel was investigated using thermogravimetry under Nitrogen atmosphere from an ambient temperature to 870 o C. The thermogravimetric data for the peel decomposition at 3 different heating rates (10, 15 and 20 o C/min), an onset and off set temperatures of 100 o C and 700 o C, and iso-conversional temperature integral methods (Flynn Wall Ozawa and Kinsinger Akahira Sunose) were used to evaluate the non-isothermal decomposition kinetics of the peel. The minimum (Ea,min), maximum (Ea,max) and average (Ea) apparent activation energies using the FWO model were 28.810 kJ/mol, 37.340 kJ/mol and 31.948 kJ/mol respectively while the minimum (Ea,min), maximum (Ea,max) and average (Ea) apparent activation energies using the KAS model were 20.406 kJ/mol, 28.134 kJ/mol and 23.619 kJ/mol respectively. The minimum (K0,min), maximum (K0,max) and average values for pre-exponential factor, which was expressed as a shape function of the activation energies distribution and optimized, were 3.9291 min-1 , 22.8529 min-1 , and 9.2963 min-1 , for FWO model and 0.00015 min-1 , 0.00055 min-1 and 0.00027 min-1 , for KAS model respectively. The order of the reaction was 1.0001. The extent of mass conversion was dependent on the apparent activation energy Ea and pre-exponential factor values which confirm evidence of multi-step decomposition kinetics, an assumption made for iso-conversional models development. The thermal profile and kinetic data obtained for the avocado peel could be deployed in a pilot scale to assess its thermal stability and economic viability and also in modeling, designing and developing thermo-chemical system for the conversion of the avocado peel.
... With the increasing shortage of fossil fuels and the growing problems of environmental pollution and greenhouse effect caused by long-term applications, the utilization of biomass by pyrolysis has received widespread attention [1,2] . The biomass pyrolysis process is significantly affected by the treatment process, reaction conditions, and material sources, especially the structure of lignin-rich biomass fractions from different sources varies greatly, so the study of pyrolysis for different sources of biomass and its various single-component model compounds is an important part of biomass thermal conversion research [3][4][5][6][7] . ...
Article
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The regularity and variability of the composition distribution of the pyrolysis products of corn stover fermentation residue and phenolic resin with the pyrolysis temperature were investigated by thermogravimetry (TG) and lyser-gas/mass spectrometer (Py-GC/MS). The results show that toluene, phenol and methyl phenol are the main common components of the two systems, 2,3-dihydrobenzofuran, alkoxy compounds and a small amount of carboxylic acid are the unique components in the pyrolysis products of corn straw fermentation residue, while dimethyl phenol, 9H-xanthene and other components in the phenolic. This is a reflection of the differences in the composition and structure of the two raw materials.
... Unlike fossil fuels, biomass sources, such as forestry and agricultural remnants, are planted and collected annually, and they can provide a continuous energy supply. Fast pyrolysis of biomass is considered to be one of the most promising ways of utilizing these resources (Bridgwater 2012). Conventional fast pyrolysis of biomass mainly focuses on the production of bio-oil, which can be readily stored and further used as biofuels or fine chemicals. ...
Article
The catalytic microwave-assisted pyrolysis of pine sawdust using SiC and Ni modified HZSM-5 as microwave absorbent and catalyst for high quality bio-oil production was investigated. The Ni modified HZSM-5 catalyst was successfully prepared through the co-precipitation method and further characterized by X-ray diffraction (XRD) and surface area and pore size analyses. The product yield results showed that Ni modified HZSM-5 catalyst decreased the bio-oil yield and increased the gas yield. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the bio-oil mainly contained alcohols, aldehydes, ketones, carboxylic acids, furans, and phenolics. The Ni modified HZSM-5 catalyst dramatically decreased the carboxylic acids and ketones content, while it remarkably increased phenolics, especially the phenol content. The physical property analysis showed that the bio-oil with the Ni modified HZSM-5 catalyst had a higher calorific value. Therefore, under microwave-assisted pyrolysis conditions, Ni modified HZSM-5 catalyst had a remarkable effect for improving the quality of bio-oil.
... Biomass, as a kind of renewable energy which can be transformed into a variety of chemicals, has been widely concerned because of its wide distribution, rich variety, and environmental protection [1,2]. Biomass pyrolysis technology is one of the important ways of biomass energy conversion and utilization [3]. Under the condition of anoxia and high temperature, the macromolecules are cut off and convert into bio-oil, which is a potential liquid fuel and can also be used to produce furfural, aromatics, and other important chemicals [4]. ...
Article
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The application of biomass pyrolysis was still limited owing to the high pyrolysis temperature and the complicacy of pyrolysis products. In this work, a homogeneous low-temperature cellulose catalytic pyrolysis system is proposed to directional products 5-methylfurfural. The low-temperature catalytic activity and products distribution of cellulose pyrolysis in [bmim][FeCl4] (Fe-IL) and [bmim]2CoCl4 (Co-IL) at temperature gradients from 150 to 300 °C were studied. As the results, both Fe-IL and Co-IL can catalyze the pyrolysis of cellulose, especially for Fe-IL, which effectively reduced the pyrolysis temperature of cellulose to 200 °C. Nano-scale and micron-scale particles were produced by the catalysis of Fe-IL and Co-IL, respectively. Fe-IL have a high selectivity for the production 5-methylfurfural (5-MF) and furfural (FF), which were 71.12% and 19.14% respectively at the pyrolysis temperature of 200 °C. Furthermore, the mechanism of low-temperature catalytic pyrolysis and the directional evolution mechanism of 5-MF and FF were suggested. Graphical abstract
... Pirolisis adalah proses dekomposisi termokimia biomassa yang berlangsung tanpa udara pada rentang suhu 400 -600 o C (Bridgwater, 2012). Hasil dari proses pirolisis berupa arang, bio-oil/tar, dan gas. ...
Article
p>Ketersediaan bahan bakar sebagai energi semakin menurun, sehingga dibutuhkan suatu energi alternatif dalam upaya menunjang ketersediaan energi, salah satunya melalui pemanfaatan proses pirolisis biomassa. Proses katalitik pirolisis biomassa menjadi pilihan baru karena dapat menurunkan input energi, konsumsi waktu serta meningkatkan kualitas produksi syngas dibandingkan dengan non-katalitik. Tujuan penelitian ini adalah menentukan analisa karakteristik termal dan analisis yield syngas dalam penambahan fly ash sebagai katalis dalam proses pirolisis sekam padi. Penggunaan fly ash sebagai katalis menjadi salah satu alternatif dalam pemakaian katalis murah. Sampel biomassa sekam padi dihaluskan terlebih dahulu lalu dilakukan penyaringan hingga ukuran -140+200 mesh (0,074 – 0,105 mm). Fly ash yang merupakan limbah hasil pembakaran batubara diperoleh dari industri pembangkit listrik juga disaring dengan ukuran yang sama. Kemudian fly ash dan sekam padi dicampurkan untuk dibentuk pelet dengan variasi sampel penambahan fly ash 5% (FARH5), 10% (FARH10), 20% (FARH20) dari massa sekam padi. Pelet yang dihasilkan berukuran diameter 5 mm dan panjang 13 ‒ 15 mm. Proses pirolisis dilakukan dalam laju pemanasan 10 °Cmin<sup>-1</sup> hingga mencapai suhu 600 °C menggunakan alat makro-TGA dengan gas nitrogen sebagai gas pembawa. Hasil syngas dari proses pirolisis ditampung dalam gas bag untuk dianalisis menggunakan GC. Pengolahan data hasil pirolisis dilakukan untuk mengetahui karakteristik termal melalui metode DTG ( Differential Thermogravimetric ) . Hasil dari penelitian ini diperoleh bahwa penambahan katalis fly ash optimal pada variabel FARH20 dapat meningkatkan laju konversi maksimum 0,00893 K<sup>-1</sup> pada suhu operasi reaksi yang lebih rendah 567,11 K dan peningkatan yield syngas pada variabel FARH10 sebesar 47,04%. The Effect of Fly Ash as a Catalyst on Pyrolysis Process of Rice Husk Pellets on Thermal Characteristics and Synthetic Gas (Syngas) Production. Utilization of the biomass pyrolysis process is one of the efforts to support alternative energy development to overcome the current declining availability of fuel. The catalytic pyrolysis of biomass is a new strategy to reduce energy input and time consumption, and improve syngas quality compared to non-catalytic. The purpose of this study was to examine the effect of fly ash as a catalyst in the process of rice husk pyrolysis as a low-cost catalyst for thermal properties and syngas yield. The rice husk biomass sample was milled and sieved to -140+200 mesh (0,074 – 0,105 mm). Fly ash, a byproduct of coal combustion obtained from the power generation industry, was sieved to the same size as well. The fly ash and rice husks were then combined to form pellets, with variations of 5% (FARH5), 10% (FARH10), and 20% (FARH20) fly ash provided to the mass of rice husks. The formed pellets have a diameter of 5 mm and a length of 1315 mm. Using a macro-TGA device and nitrogen gas as the carrier gas, the pyrolysis process was carried out at a heating rate of 10 °Cmin<sup>-1</sup> to a temperature of 600 °C. The syngas was placed in a gas bag for further examination using gas chromatography (GC). Pyrolysis data was processed to determine thermal properties using the DTG (Differential Thermogravimetric) method. The addition of an optimal fly ash catalyst in the FARH20 increased the maximum conversion rate to 0.00893 K<sup>-1</sup> at a lower reaction operating temperature of 567.11 K and increased the syngas yield by 47.04% on the FARH10.</p
... Slow pyrolysis operates at low temperatures (approximately 400 • C) and with a long residence time, ranging from hours to days to maximize char production. Whereas fast pyrolysis operates at a very high heating rate (10 3 -10 5 • C/s) and at moderate temperature (approximately 500 • C) and short residence time (<2 s) to maximize bio-oil production [78]. Several reactors, including micro-tubing reactor [79], fixed-bed reactor [80], packed bed reactor [81], and bubbling fluidized-bed reactor [82], have been studied and optimized for seaweed conversion to bio-oil. ...
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Seaweed as a third-generation biofuel feedstock can provide fuels and chemicals to offset climate change caused by fossil fuel usage and support a cleaner and thriving sea and ocean environment. However, despite several advantages, there are significant challenges to deploying commercial-scale seaweed-based biorefineries, including low-cost and large-scale seaweed cultivation, and lowering the capital and production costs of seaweed conversion to biofuels. Additionally, many conversion platforms can be used to produce biofuels from seaweed. Thus, it is still unclear which technology is economically competitive and, most importantly, the major bottlenecks in the large-scale deployment of seaweed biorefineries remain to be identified. Therefore, a detailed study was conducted to (1) analyze the global state of the seaweed industry, (2) identify platforms for seaweed-based biofuels and bioenergy production on bench-scale investigations, (3) provide a basis for future large-scale techno-economic feasibility studies on seaweed conversion to biofuels and bioenergy, (4) conduct a comparative analysis of biofuels and bioenergy production platforms using seaweed, and (5) identify the major bottlenecks in developing commercial-scale seaweed biorefineries. A comprehensive techno-economic analysis was conducted using six conversion platforms, including sugar, methane, volatile fatty acid, pyrolytic oil, syngas, and hydrothermal liquefaction oil. Based on the current market trends, the results indicated that mixed alcohols production using a volatile fatty acid platform is economically competitive, with the minimum ethanol selling price of 0.28–0.33 $/L, which is 7.8%–21.2% lower than the average wholesale price (0.36 $/L) of ethanol in 2020. In contrast, all other platforms were found to be economically unfeasible.
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Investigating suitable waste management processes is essential nowadays. Anaerobic digestion and pyrolysis are among waste treatment processes that have demonstrated promising potentials. The objective of this study is to evaluate the integration of pyrolysis and anaerobic digestion comprehensively in terms of energy/exergy analysis and comparing the integrated energy system with bare systems. To that end, novel pyrolysis and anaerobic digestion plants are designed and proposed. MATLAB was used for developing a code that simulated the plants and meanwhile, Aspen Plus provided thermodynamic properties. Results showed that the exergy efficiency of the integrated plant is 45.71%, while this parameter is 27.60% and 88.71% for the simple pyrolysis and anaerobic digestion plants, respectively. Furthermore, to make pyrolysis plant energy-independent and maximize bio-oil production, the optimum chemical composition of biomass feedstock is obtained. Seven samples were scrutinized, of which the sample with 46.00 wt% cellulose, 29.33 wt% hemicellulose, and 24.67 wt% lignin showed the optimal conditions. This composition could raise the exergy efficiency of the pyrolysis plant to 40.03%, while more interestingly exergy efficiency of the integrated system would reach 51.15%. Taken together, the findings suggested that the integration of pyrolysis and anaerobic digestion improves both exergy efficiency and methane production.
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Cellulose can be selectively converted into levoglucosenone (LGO), a high-value anhydrosugar, through fast pyrolysis with acidic catalysts. Herein, phosphorus molybdenum tin mixed metal oxides (P-Mo/SnO2) were prepared for the selective production of LGO from the in situ catalytic fast pyrolysis (CFP) of cellulose, where the PO43-, P-support, and Mo6+ species in P-Mo/SnO2 played the determining role in promoting depolymerization, dehydration, and deoxygenation reactions. Pyrolysis-chromatography/mass spectrometry (Py-GC/MS) tests were carried out to explore the influence of catalyst-to-cellulose (CA-to-CL) ratio, phosphomolybdic acid (PMA) loading, and pyrolytic reaction temperature on LGO preparation. The results demonstrated the maximal LGO yield could reach 17.98 wt % via using P-Mo/SnO2 with the PMA loading of 50 wt % at the pyrolysis temperature of 300 °C and the CA-to-CL ratio of 1:1. Moreover, the highest LGO yield could be up to 12.70 wt % in lab-scale CFP tests at 300 °C and the CA-to-CL ratio of 2:1, and the LGO yield could remain above 10 wt % after five runs of catalyst calcination regeneration.
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Higher heating value, energy and exergy analysis of bio-oil and biochar from microwave pyrolysis have been assessed. The energy efficiency for the pyrolysis system has been analyzed by the comparisons of energy based on heating values. The exergy analysis was done using standard relationships by the fraction of energy actually available for practical uses as biofuel. The yield of bio-oil and its higher heating value (HHV) were increased by 2–13% and 25–130% respectively when the microwave power increased from 500 W to 700 W, then both are decreased at 900 W. Using activated carbon (AC) had a remarkable effect on increasing the yield and HHV of bio-oil by 18–31% and 3–7 times respectively more than other cases. By using the additives, the yield of biochar decreased remarkably, while its HHV increased by 12%-40% compared to without additive. The maximum energy and exergy rate (1.74 MJ/h) of the bio-oil were obtained at 700 W level of microwave power using AC additive, while for biochar were 1.95 MJ/h and 2 MJ/h when no additive used. The maximum values of energy and exergy of the bio-oil were computed to be 27% and 26% respectively at 700 W using AC as an additive. The maximum values of energy and exergy efficiency of biochar were calculated to be 33% and 32% respectively when pyrolyzed at 500 W using AC. The energy and exergy efficiencies of the pyrolysis system were computed to be maximum value of 53.3% and 52.8% respectively at 700 W using AC additive.
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This research aimed to examine the upgrading of the sisal residue bio-oil from the relations between process conditions of the fast pyrolysis and the properties of the fluid. The bio-oil was produced in a pilot unit with a fluidized bed reactor by varying the nitrogen flow rate, biomass mass flow, temperature, and pressure. Overall, the bio-oil composition was intensely dependent on the process parameters. The pressure at the lowest value was the best condition for obtaining the bio-oil in high yield (up to 17 wt%), with the highest monomer yield (44.51 wt%) and the lowest O/C ratio (0.11). The characterization techniques applied revealed remarkably distinct characteristics between the bio-oil of sisal residue and other biomass. The sisal residue bio-oil had a lower oxygen and water content, higher thermal stability, higher degree of depolymerization, and a higher yield of aliphatics, naphthalenes, and alkylphenols.
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Biochar has become centre of attention in the recent years, for its potential role in improving soil health and agricultural productivity, carbon sequestration and also to mitigate global warming thereby providing a valuable remedy for agricultural and environmental issues. Biochar is carbon-rich material obtained by heating any organic matter in a closed container under absence or limited supply of oxygen. It is often prepared from a variety of feedstocks under different pyrolysis conditions, thus affecting the properties of biochar. Consequently, the effectiveness of biochar as an amendment of soil contaminated varies. It is increasingly being documented that biochar plays significant role in reducing the bioavailability, hence biotransformation and bioremediation of heavy metals in contaminated soil. Recently, the accelerating urbanization and rapid advancements in the agricultural and industrial technologies have led to escalation in contamination of soil particularly with heavy metals, thereby causing serious health issues and ecological risks. Biochar has been widely recognized as a promising material to effectively immobilize heavy metals in contaminated soil. This chapter describes the overview on soil contamination by heavy metals, different methods of biochar production, characteristics and the factors affecting the properties of biochar, the interaction of biochar with soil microbes, plants and heavy metals, and the potential role of biochar in phytoremediation and microbial remediation of heavy metal-contaminated soils. Besides, the possible limitations of biochar such as release of toxic substances, activation of certain heavy metals and difficulty in weed control in biochar-amended soil are also discussed. Some key areas related to the potential unintended effects of biochar need to be addressed so as to channelize the research in ensuring the sustainable use of biochar.KeywordsBiocharHeavy metal contaminationSoil microbesBioremediation
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Background Pyrolysis is an alternative heating method developed to produce bio-oil, biogas, and biochar from biomass, including oil palm empty fruit bunch (EFB) and rice husk (RH) pellets. This work focused on the comparison of the products obtained from microwave pyrolysis (MP) and conventional pyrolysis (CP). Methods The experimental work was carried out using MP and CP at 500 °C and 800 °C. The properties of biochars produced from these reactions were characterized. The biofuels were characterized using FTIR and GC-MS, while the biogas was measured using GC-TCD. The composition of the H2 gas or syngas was also analyzed. Significant Findings MP improved the yield of bio-oil and biochar, but the percentage of biogas yield decreased. The yield of bio-oil produced from the MP of RH and EFB pellets reacted at 800 °C increased significantly from 12.2 to 20.6 wt.% and 15.5 to 20.2 wt.%, respectively. The bio-oil derived from MP has a high content of monoaromatics and phenolic compounds compared to the oil produced from CP. Meanwhile, the bio-oil derived from CP contained a significant amount of polycyclic aromatic hydrocarbons. Although the yield of biogas produced via MP was slightly lower than CP, the total syngas produced from MP was significantly high for both EFB (78 vol.%) and RH (70 vol.%). For CP, only 62 vol.% and 68 vol.% of syngas was produced using EFB and RH, respectively. The findings highlight the potential of MP technology to synthesize environmentally-friendly bio-oil and biogas with a high percentage of syngas.
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Bio-fuels such as biodiesel and pyrolysis oil (bio-oil) are gaining popularity as a way to address challenges such as global warming, high oil prices, and depletion of the oil reserves. The focus of this research is to transform waste non-edible Honge de-oiled seedcake into Honge bio-oil (HBO) via pyrolysis and use of HBO in a diesel engine. Crude bio-oil extracted through the pyrolysis process cannot be used directly to power a diesel engine due to its weak fuel properties. However, with the aid of emulsifiers like Span-80 and Tween-80, the bio-oil can be upgraded by emulsification method and adapted as fuel to diesel engines. The performance and emissions of a diesel engine fueled with various HBO-diesel emulsions were investigated and compared to base diesel. At full load, the emulsion blend with 20% HBO and 80% diesel had slightly improved brake thermal efficiency than that of the base diesel. The emissions like carbon monoxide, oxides of nitrogen, and hydrocarbons are found to be reduced significantly with HBO-diesel emulsions. In addition, the smoke emission was reduced considerably. Hence, HBO can be used as an alternative to the diesel fuel.KeywordsPyrolysis oilEmulsionsDiesel engine
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Actualmente, la política energética del Perú busca reducir el uso de fuentes energéticas provenientes de los hidrocarburos, dado su alta inestabilidad en los precios y sus altos índices de contaminación; por ello el Perú se encuentra modificando su matriz energética al incorporar fuentes renovables de energía, con la finalidad de evitar la escasez de combustibles con perspectiva de conseguir una región ambientalmente responsable y moderna, que deberá contar con la participación de la población. Es así que el fomento de los biocombustibles se ha convertido en una de las más importantes respuestas políticas ante la dependencia de las fuentes fósiles, tal como indican los autores Salas, Islas y Muñoz (2008), esto ha llevado al Gobierno Peruano a entrar en la era de los biocombustibles mediante la LEY N°28054, que en su artículo 1 «establece el marco general para promover el desarrollo del mercado de los biocombustibles sobre la base de la libre competencia y el libre acceso a la actividad económica, con el objetivo de diversificar el mercado de combustibles, fomentar el desarrollo agropecuario y agroindustrial, generar empleo, disminuir la contaminación ambiental y ofrecer un mercado alternativo en la lucha contra las drogas» (Ley N°28054, 2005, p.1). El impulso que dio el gobierno para incluir los biocombustibles en la matriz energética, conlleva a una gran demanda de cultivos energéticos (como es el caso de la palma
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This short critical review gives an insight on the potential that lignin and its bio-oils present towards the production of thermosetting epoxy polymers and composites. Green and sustainable ways of producing monomers and polymers from renewable sources are critical and lignin, as an underutilized bio-based waste material, presents a high exploitation potential. Due to its versatile and highly functional phenolic structure, the utilization of lignin or its depolymerized fractions (bio-oils) has been investigated in the last years as alternative for fossil-based epoxy resin pre-polymers and crosslinkers. Lignin can in fact be considered as a crosslinker for epoxy resins, especially after appropriate functionalization with amine groups or with additional hydroxyl groups, or it can be modified with epoxide groups towards the replacement of toxic BPA-based epoxy prepolymers. Furthermore, lignin derived pyrolysis or hydrogenolysis bio-oils may offer highly reactive soluble oligomers that after appropriate functionalization could be utilized as bio-based epoxy prepolymers. The lignin-based epoxy resins and composites exhibit similar or even better and novel properties, compared to those of pristine epoxy polymers, thus rendering lignin a highly valuable feedstock for further utilization in the thermoset polymer industry.
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Lignocellulosic biomass, mainly composed of cellulose, hemicellulose, and lignin, can be converted into fuels and chemicals using biochemical or thermochemical conversion processes. Principles and recent development of major thermochemical conversion technologies, including hydrothermal pretreatment, hydrothermal liquefaction, hydrothermal carbonization, pyrolysis, gasification, and clean combustion, are discussed in this chapter. In addition, major influencing factors and existing problems of each thermochemical conversion technology are reviewed. Finally, the characterization of value-added products from the biomass thermochemical conversion is summarized. This chapter aims to assist policymakers, researchers, and producers in the transformation of biomass thermochemical technologies from the research labs to the commercial markets.
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A B S T R A C T In the context of the COVID-19, the co-pyrolysis of waste cotton swabs and non-woven masks is a promising way of biomass utilization. On the one hand, it alleviates the energy crisis to some extent, and on the other hand, it is conducive to the proper disposal of medical waste. In this paper, the pyrolysis process and kinetic behavior of two materials under different conditions including mixing ratios, heating rates and catalyst additions were studied. The results show that the heating rate has little effect on the pyrolysis process. Mask has better pyrolysis performance than cotton swabs and could promote the decomposition of biomass as an auxiliary material. All the blends show a certain synergistic effect. The difference between the actual mass loss and the theoretical mass loss (ΔW) is positive and the activation energy is lower than that of any single component. The addition of catalyst can further promote the pyrolysis reaction, and the residual mass is greatly reduced. This paper aims to provide some suggestions for further exploration in related fields.
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Wheat straw is a renewable agricultural by-product that is currently underutilized in the production of bioenergy and bioproducts due to its high ash content, as well as high transport costs due to its low volumetric energy density. The thermogravimetric analysis of this material produces derivative curves with a single broad peak, making it difficult to identify the three conventional pseudo-components (cellulose, hemicellulose, and lignin), which is resolved using the second derivative to determine inflection points. Model-fitting methods and isoconversional methods were applied to determine the degradation kinetics of wheat straw at two different particle sizes, as well as that of a reference feedstock (beech wood), and the obtained values were used to divide the degradation curves to be compared to the experimental data. Seven different pyrolysis reaction networks from the literature were given a similar treatment to determine which provides the best estimation of the actual pyrolysis process for the case of the feedstocks under study. The impact of the potassium content in the feedstock was considered by comparing the original pathway with a modification dependent on the experimental potassium content and an estimated optimum value.
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The present work deals with the physicochemical properties and thermal decomposition performance of waste biomasses-elephant grass (EG), sugarcane bagasse (SB), and rice husk (RH). The physicochemical properties of the selected feedstocks are evaluated by their heating value, proximate and ultimate analyzes, and thermogravimetric analysis. The maximum calorific value is obtained for elephant grass (16.860 MJ/kg). The pyrolysis study of the feedstock was done using thermogravimetric analysis. The pyrolysis of the feedstocks is illustrated by three distinctive phases. TGA result reveals that solid weight loss after completion of the pyrolysis process is maximum for EG (79.55 wt.%). The activation energy (Ea) of the selected biomasses was determined using the iso-conversional model (Flynn-Wall-Ozawa). Average values of the activation energy are observed to be 209.4 kJ/mol for rice husk, 182 kJ/mol for sugarcane bagasse, and 130.4 kJ/mol for elephant grass, respectively.
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The increasing pressure to decarbonize has incentivized several oil refineries to repurpose their oil refiners to “stand-alone biorefineries” that produce lower carbon intensive (CI), drop-in biofuels. This has typically involved modifying older, uneconomic refineries that have processed various types of fossil-derived oil feedstocks to process a range of lower carbon intensive (CI) oleochemical/lipid feedstocks such as used cooking oil (UCO). Refineries where the hydroprocessing unit predominates have been the major producers of drop-in biofuels such as renewable diesel and biojet/sustainable aviation fuels (SAF). However, modifications to unit operations, such as the hydroprocessing facility, are typically required while, how the deoxygenation of the oleochemical feedstocks is carried out is influenced by a variety of considerations. The carbon intensity of the final fuels is influenced by several factors such as the source of the lipid feedstock, the nature of the hydrogen used to upgrade the feedstocks, the potential use of “green” electricity, etc. As is being pursued by several companies, co-processing provides a way to lower the carbon intensity of the final fuels without the need for major infrastructure changes within the refinery. However, access to oleochemical feedstocks is anticipated to become increasingly challenging due to cost and availability. Consequently, the use of biomass-derived-biocrudes in both stand-alone and co-processing facilities is anticipated to increase. The use of more variable and diverse biogenic feedstocks will require further modification of refinery operations, particularly those facilities which co-process low CI feedstocks at the hydroprocessor rather than at the Fluid Catalytic Cracking (FCC) unit.
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Waste biomass, such as agricultural waste, is emerging as a promising renewable energy resource because of its abundance and carbon-neutral nature. It has a high potential to be used as an alternative source of energy by employing thermochemical conversion techniques. Pyrolysis is the most efficient technique for the conversion of biomass-based waste in manufacturing renewable fuels and chemicals. However, despite pyrolysis being a well-known method to provide solid fuel (charcoal) and chemicals, the technological pathways for producing chemicals and liquid fuels at an industrial scale are not fully developed. This review addresses the relevance of pyrolysis for waste-to-energy and materials, the fundamentals of pyrolysis, different reactors, process conditions, and its products from the perspective of energy and materials recovery. Accordingly, the purpose of this review is to analyse the current application level of pyrolysis for waste management, identify gaps in our current understanding, and recommend future research directions.
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Sustainable bio-economics can be achieved by the processing of renewable biomass resources. Hence, this review article presents a detailed analysis of the effect of susceptors on microwave-assisted pyrolysis (MAP) of biomass. Biomass is categorized as lignocellulosic and algal biomass based on available sources. Selected seminal works reporting the MAP of pure biomasses are reviewed thoroughly. Focus is given to understanding the role of the susceptor used for pyrolysis on the characteristics of products produced. The goal is to curate the literature and report variation in the product characteristics for the combinations of the biomass and susceptor. The review explores the factors such as the susceptor to feed-stock ratio and its implications on the product compositions. The process parameters including microwave power, reaction temperature, heating rate, feedstock composition, and product formation are discussed in detail. A repository of such information would enable researchers to glance through the closest possible susceptors they should use for a chosen biomass of their interest for better oil yields. Further, a list of potential applications of MAP products of biomasses, along with the susceptor used, are reported. To this end, this review presents the possible opportunities and challenges for tapping valuable carbon resources from the MAP of biomass for sustainable energy needs.
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El biochar, es uno de los productos de la pirólisis, el cual es un producto enriquecido de carbono orgánico. Por sus propiedades químicas es usado como enmienda para mejorar las propiedades físicas del suelo y fija carbono orgánico. Además, el biochar es utilizado como una alternativa de manejo de residuos agroforestales por su alta proporción de biomasa lignocelulósica. Por lo tanto, el objetivo del presente trabajo es evaluar la calidad del biochar producido a partir de residuos agroforestales, en base a las características establecida por el IBI; además se evaluará la estabilidad del mismo.
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The residues of alfalfa and goldenrod, after supercritical CO2 extraction, were examined against raw plant materials to determine the capacity to carry micronutrients and energy production. Materials were enriched with Cu(II), Mn(II) and Zn(II), via biosorption and subjected to multielemental analysis and determination of nitrogen. The materials showed a high capacity for Cu(II)>Zn(II) > Mn(II), whose content increased by 104–1262 and 54–2460 times in post- and prior-extraction samples, respectively. The goldenrod residues provided the best results for Mn(II) (14,000 mg/kg) and Zn(II) (18,500 mg/kg), while alfalfa residues bound more Cu(II) (13,800 mg/kg). Materials meet the EU regulation requirements for organo-mineral fertilisers. During thermal breakdown, two combustion steps lead to 83–85% weight loss. The thermal response included two exothermic effects at 120–400 °C and 400–620 °C releasing the energy of 3.4–4.5 μV/mg and 6.1–7.0 μV/mg, respectively. Alfalfa matrices provided stronger thermal effects. The materials emit H2O, CO2 and SO2. Extraction caused an increase and a slight decrease of the energy released by alfalfa during the first and second combustion steps, respectively. The residues contained less water than the raw materials and could be applied as solid biofuel or as combustion promoters. Laboratory-scale experiments proved that the residues after extraction were suitable in both applications.
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Bio-oil from biomass pyrolysis offers a wide range of applications such as transport fuels, value-added chemicals, materials, or heat and power generation. However, fresh bio-oil is unstable due to its physicochemical properties, chemical composition, and multiphase behaviors changing with time. The bio-oil aging kinetic model based on the change in carbonyl content was developed, and the pattern search method was proposed to optimize the model parameters. The accelerated and long-term aging kinetic behaviors of two bio-oil samples could be described accurately by the carbonyl-based aging kinetic model. The reaction rate constant values for the long-term and accelerated aging of bio-oil 1 were 1.694 × 10⁻⁴ and 4.589 × 10⁻² h⁻¹, whereas 3.084 × 10⁻⁴ h⁻¹ and 1.329 × 10⁻¹ h⁻¹ were reported for bio-oil 2, respectively. The reaction order values of the long-term aging (2.452 for bio-oil 1 and 3.973 for bio-oil 2) were higher than that of the accelerated aging (0.943 for bio-oil 1 and 1.000 for bio-oil 2). Two bio-oil samples showed different aging kinetic characteristics due to different raw materials, pyrolysis reactor types and conditions, and bio-oil phases for aging tests. The hydration, hemiacetal, acetal and polymerization reactions of carbonyl compounds were the primary mechanisms for the change in carbonyl content during bio-oil aging.
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Biomass residues and waste can be converted into bioliquids by pyrolysis, which can contribute to both the production of renewable fuels and the recycling of waste. In this paper, the pyrolysis of pure beech wood (BW) and of a mixture of BW + polyamide-6 (PA6), a nitrogen-containing plastic, was investigated to assess the effect of PA6 on the properties of bio-oils, obtained either by thermal pyrolysis or by pyrolysis with ex-situ catalytic treatment of the vapors. The presence of 20 wt.% PA6 in the blend affected the pyrolysis products yields and distribution (gases, liquids, chars), but also the composition of the bioliquids. In absence of a catalyst, the production of phenolic compounds (guaïacol, syringol…), sugars, furans decreased significantly with the BW+PA6 blend compared to pure BW, and N-containing compounds derived from PA6 were found in the bioliquids. When HZSM-5 catalyst was applied for the treatment of vapors, a beneficial effect of the catalyst on the reduction of the sugars and furans content in the bioliquids and on the production of deoxygenated compounds was observed with pure BW. This effect was mitigated with BW+PA6 blends and the formation of fully deoxygenated compounds was almost totally suppressed, suggesting that the strong catalyst acid sites were poisoned. Caprolactam was by far the main product of PA6 degradation found in the bioliquids, but the N-containing by-products were different depending on the absence or presence of HZSM-5 catalyst. In particular, the formation of 5-cyano-1-pentene in a fairly large proportion was only observed in the presence of the catalyst.
Article
In this paper, an efficient nickel-cobalt bimetallic catalyst was designed and developed for catalytic hydrogenation of furfural, one of the biomass platform products, to 2-methylfuran, a high value-added chemicals. The NiCo-MgAlO catalysts were synthesized by the co-precipitation method and characterized by H2-TPR, XRD, N2 adsorption-desorption analysis, O2-TPO, FAL-TPD, NH3-TPD, TEM and other methods. These results revealed that the Ni/Co ratio, solvent, reaction temperature, pressure, time, and, most importantly, the catalyst reduction conditions had a major impact on this reaction. 100% of furfural conversion and 92.3% of 2-MF selectivity were achieved over the Ni10Co5-MgAlO-3h catalyst with its Ni/Co molar ratio of 2 when employed 2-butanol was the solvent. It could maintain high activity even after using it several times. The bimetallic Ni10Co5-MgAlO catalyst owned homogeneous composition of Ni-Co alloy nanoparticles and more middle-acid sites than the monometallic Ni10-MgAlO catalyst, which might promote C-O bond cleavage and improve 2-MF selectivity due to its oxygen affinity. The high yield of 2-methylfuran from furfural may be due to the synergistic effects of the metal sites and the acid sites on the Ni-Co bimetallic catalyst's surface.
Chapter
Rising energy demands and depletion of fossil fuels have led the research community to investigate alternative fuel sources. Green and renewable biofuels have evolved to substitute for a non-renewable energy source. Biomass can be utilized as a raw material for producing low-carbon fuels. Although biomass-based fuels can replace fossil fuels, direct use is limited due to the low quality of the fuels and expensive process costs. An unrivaled solution to this problem is an integrated biorefinery concept involving generating hydrocarbon-grade fuels and valuable chemicals from pyrolysis-derived bio-oil. The chapter examines recent breakthroughs in bio-oil up-gradation processes and moisture removal techniques and bio-oil recovery of valuable compounds. One of the widely used and well-developed techniques for producing bio-oil is the fast pyrolysis of biomass. The catalytic cracking process has been identified as a viable technology for converting bio-crude to liquid fuel in bio-oil upgrading. The chapter examines recent trends and advances in the fast pyrolysis technique to improve overall profitability of the process. Critical analysis of the potential and existing techniques and necessary future steps are essential for adopting these methods industrially and in a feasible manner.KeywordsPyrolysisUpgraded fuelGreen fuelBiomass
Article
The significant progress in energy demands and limited fossil fuel sources, together with environmental concerns, have enforced the study of green, renewable, and sustainable energy sources. Biomass and its residues can be converted into valued fuels and chemicals through advanced thermal conversion technologies. Pyrolysis has been used for a long time for charcoal formation, while intermediate and fast pyrolysis technologies have become of considerable interest in recent years. This substantial interest is because these processes provide different bio-products (synthesis gas, bio-oil and biochar), which can be used directly in numerous applications or as a sustainable energy carrier. This paper investigates an overview of the fundamentals of Thermo-Catalytic Reforming (TCR) technology which is a novel intermediate pyrolysis process combined with a post catalytic reforming unit. This study also identifies the TCR process's features and advantages compared to other pyrolysis technologies, followed by a technical scale unit and the transfer of intermediates in final products. Finally, the treatment of effluents, heat management and implementation of such technologies are discussed. This paper shows how a continuous pyrolysis/reforming plant has been developed and established based on targeted reactor design and in conjunction with preventing major effluent streams, which could have a major impact on the technology's commercial success. Along with two major European projects (To-Syn-Fuel and GreenFlexJET), the TCR technology shall help to overcome the dependency on fossil crude oil and fuels.
Article
The main objective of these studies was development of competitive catalyst for the upgrading of biomass pyrolysis vapors to H2-rich gas. The performed experiments were devoted to determination of the effect of incorporation of zirconium into the structure of BEA zeolite on the performance of NiBEA in the mentioned process. Moreover, the most important parameters responsible for the increased activity of NiZrBEA catalyst in comparison to nickel supported on parent zeolite have been identified. The activity of synthesized catalysts was tested in two step fixed bed quartz reactor. Firstly, cellulose or pine were heated to the 500 °C in order to decompose lignocellulosic feedstock. Then, formed pyrolysis vapors were directed through catalyst bed (700 °C) where their upgrading took place. The obtained results revealed that an introduction of zirconium in the structure of BEA zeolite allowed for the increase in the efficiency of Ni catalyst in the formation of H2-rich gas. It was related to the increase in pore volume of the synthesized materials, formation of smaller nickel oxide crystallites and creation of the catalysts with moderate acidity.
Article
This review paper aims to explore the research progress in the formation of hydrogen rich gas from different innovative coal gasification parameters. Promotion effects of parameters such as pressure, temperature, catalyst, coal type, reactor setup, and gasification agents (H2O, O2, supercritical water) were extensively analysed. The formation of hydrogen gas through coal gasification was sub-divided into H2 production from fixed bed gasification system, fluidised bed system, and entrained flow system. The advantages of coal and biomass co-gasification towards clean energy formation was also reviewed. Co-gasification and Elevated temperatures, pressures, and steam-carbon ratios were reported to positively influence the yields of H2 gas by facilitating steam reforming and water gas shift reactions. The presence of different catalyst and sorbents in the gasification reaction systems was also noticed to enhance the concentration of hydrogen in the gaseous products. Production of hydrogen rich syngas from fixed bed and fluidized bed gasifiers was assessed, and both methods were found to favour the formation of hydrogen gas. The polygeneration of hydrogen gas, electricity and carbon dioxide capture was discovered to be feasible via coal gasification techniques.
Article
Full-text available
Biomass fast pyrolysis liquid is being developed for fuel and chemical applications. As these developments proceed, the liquid product is increasingly being transported by air, water, rail and road to satisfy user demands for products. This paper addresses the legislative requirements and regulations for the safe transport of this liquid. As biomass derived fast pyrolysis liquid is not on the UN approved carriage lists; its own classification has been determined from the UN manual as: UN 1993 Flammable Liquid [Fast Pyrolysis Liquid], n.o.s., 3, 1º(a), 2º(a), 1 This classification should be used on all packages containing biomass fast pyrolysis liquid. Protocols for the labelling of packages and containers of all sizes are given with the aim of compliance with transport regulations in the EU, Canada and the USA. In conjunction with the requirements for packaging and labelling, guidance on the details to be enclosed on the transportation documents are given, with appropriate MSDS for the liquids. Guidance on the handling of fast pyrolysis liquid and its storage are given with procedures for treatment of spills.
Patent
Full-text available
The disclosure encompasses in-line reactive condensation processes via vapor phase esterification of bio-oil to decease reactive species concentration and water content in the oily phase of a two-phase oil, thereby increasing storage stability and heating value. Esterification of the bio-oil vapor occurs via the vapor phase contact and subsequent reaction of organic acids with ethanol during condensation results in the production of water and esters. The pyrolysis oil product can have an increased ester content and an increased stability when compared to a condensed pyrolysis oil product not treated with an atomized alcohol.
Article
Full-text available
This publication is an updated version of a study on testing and modifying standard fuel oil analyses (Oasmaa et al. 1997, Oasmaa & Peacocke 2001). Additional data have been included to address the wide spectrum of properties that may be required in different applications and to assist in the design of process equipment and power generation systems. In addition, information on specifications and registration is provided. Physical property data on a range of pyrolysis liquids from published sources have been added to provide a more comprehensive guide for users.
Conference Paper
Full-text available
Bio-oils produced from fast pyrolysis of biomass are chemically complex compounds. As fuels they have a number of negative properties such as high acidity, water content, variable viscosity and heating values about half that of petroleum fuel. These negative properties are related to the oxygenated compounds contained in bio-oils that result in a 45% oxygen content. For production of a viable fuel the raw bio-oils must be upgraded. The bio-oil hydrotreating process has been approached by applying hydrogenation catalysts under heat and pressure. Researchers have reported application of a successful two-stage catalytic hydrodeoxygenation (HDO) process. We have recently developed a two-stage HDO catalysis as well. The upgraded bio-oil contains hydrocarbons very similar to petroleum fuels. Yields of the upgraded bio-oils are more than 70% by energy capture. Future research on the upgraded product will focus on distillation and introduction into petroleum refineries and investigating the potential for direct blending with current petroleum fuels.
Conference Paper
Full-text available
Experimental results and a process design will be presented for an integrated process which uses hydropyrolysis plus hydroconversion to convert biomass into gasoline and diesel. The hydrogen needed for the hydropyrolysis and hydroconversion process is produced by reforming the light gases so that no external H2 is required. Finished hydrocarbon products with less than 2% oxygen are produced using this processing approach. This design solves many of the problems associated with pyrolysis and subsequent upgrading. By having an integrated process, a fungible finished product is produced which has the oxygen removed and is ready for use. This eliminates the need for transporting high TAN, unstable, low BTU content pyrolysis oils. An integrated process also eliminates the problems associated with upgrading pyrolysis oils which were created in a hydrogen starved environment and therefore include high olefinic, polynuclear aromatics and free radicals which were not present in the original biomass. Pyrolysis oils require high pressure to convert because of the condensed ring aromatic structures present. Hydropyrolysis oils can be converted at moderate pressure. The initial hydropyrolysis step is done at moderate pressure and then feeds directly into the hydroconversion step run at almost the same pressure. The light gases from the hydroconversion then go to a small steam reformer where the H2 is made and the CO2 rejected. The H2 produced is recycled back to the hydropyrolysis step. Initial data which shows the yields and product properties from experiments in pilot scale equipment will be presented and compared to results for traditional pyrolysis. Some economic analysis will also be done to show the advantages of integrated balanced hydropyrolysis + hydroconversion compared to traditional approaches.
Article
In order to gain insight into the fast pyrolysis mechanism of biomass and the relationship between bio-oil composition and pyrolysis reaction conditions, to assess the possibility for the raw bio-oil to be used as fuel, and to evaluate the concept of spout-fluidized bed reactor as the reactor for fast pyrolysis of biomass to prepare fuel oil, the composition and combustion characteristics of bio-oil prepared in a spout-fluidized bed reactor with a designed maximum capacity 5 kg/h of sawdust as feeding material, were investigated by GC-MS and thermogravimetry. 14 aromatic series chemicals were identified. The thermogravimetric analysis indicated that the bio-oil was liable to combustion, the combustion temperature increased with the heating rate, and only minute ash was generated when it burned. The kinetics of the combustion reaction was studied and the kinetic parameters were calculated by both Ozawa-Flynn-Wall and Popsecu methods. The results agree well with each other. The most probable combustion mechanism functions determined by Popescu method are f(a)=k(1-a)2 (400-406°C), f(a)=1/2k(1-a)3 (406-416°C) and f(a)=2k(1-a)3/2 (416-430°C) respectively.
Book
This book is for chemical engineers, fuel technologists, agricultural engineers and chemists in the world-wide energy industry and in academic, research and government institutions. It provides a thorough review of, and entry to, the primary and review literature surrounding the subject. The authors are internationally recognised experts in their field and combine to provide both commercial relevance and academic rigour. Contributions are based on papers delivered to the Fifth International Conference sponsored by the IEA Bioenergy Agreement.
Chapter
IntroductionMaterials and Methods ResultsMaximis Ation Function of CarbonizationPyrolytic Carbon DepositionConclusion References
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IntroductionMaterials and Methods Results and DiscussionConclusion AcknowledgmentReferences
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IntroductionExperimentalResults and DiscussionConclusion AcknowledgementsReferences
Chapter
IntroductionRating Index (RI)Step Wise Procedure to Calculate Rating IndicesBiomass Characterisation Based on NriConclusions References
Article
Hydrogen was prepared via catalytic steam reforming of bio-oil which was obtained from fast pyrolysis of biomass in a fluidized bed reactor. Influential factors including temperature, weight hourly space velocity (WHSV) of bio-oil, mass ratio of steam to bio-oil (S/B) as well as catalyst type on hydrogen selectivity and other desirable gas products were investigated. Based on hydrogen in stoichiometric potential and carbon balance in gaseous phase and feed, hydrogen yield and carbon selectivity were examined. The experimental results show that higher temperature favors the hydrogen selectivity by H2 mole fraction in gaseous products stream and it plays an important role in hydrogen yield and carbon selectivity. Higher hydrogen selectivity and yield, and carbon selectivity were obtained at lower bio-oil WHSV. In catalytic steam reforming system a maximum steam concentration value exists, at which hydrogen selectivity and yield, and carbon selectivity keep constant. Through experiments, preferential operation conditions were obtained as follows: temperature 800-850°C, bio-oil WHSV below 3.0 h-1, and mass ratio of steam to bio-oil 10-12. The performance tests indicate that Ni-based catalysts are optional, especially Ni/a-Al2O3 effective in the steam reforming process.
Article
Fractional catalytic pyrolysis is a process selectively targeting individual biopolymer components of the biomass to produce specific product slates. This method was used to screen several biomass feedstocks (switchgrass, corn stover, pinewood, hybrid poplar wood, oakwood) for adhesives production. Pyrolysis experiments were conducted at 400 to 450 °C and pyrolysis oil yields ranged from 30-50 wt%. The oils had very low molecular weight, low viscosity and pH of 3-4. The oils were used as substitutes for phenol in phenol /formaldehyde reactions. Both Novolac and Resol resins were prepared from the oils. For these reactions, there was no need for any pretreatments such as extractions, filtrations or neutralization (they were used as received). Excellent polymerization results were obtained and up to 95 wt% of the phenol could be replaced by the oils. The results were similar for all feedstocks except switchgrass oils which did not form good resins. All the oils were rich in both hydrocarbons and phenolics. However, the switchgrass oil had the highest hydrocarbon fraction.
Chapter
Within the framework of the applied research carried out by ENEL, aimed at utilising non-traditional fuels derived from the renewable resources of the territory, the Thermal Research Centre of Pisa has realized a R&D plant for bio-oil production, through a flash pyrolysis process of vegetable biomass. The Project, that is being carried out in close collaboration with the Umbria Region, is partially financed by EU. The plant has been erected at the ENEL thermoelectric power plant of Bastardo (Perugia). The process unit (RTP-Rapid Thermal Processing) has been developed by the Canadian Ensyn Company, whereas ENEL has designed and constructed the auxiliary facilities. The plant, with a capacity of processing 15 tonnes/day of dry feedstock and capable of producing around 10 tonnes/day of liquid fuel, is the largest plant of this type in Europe. The paper describes the technical characteristics of the plant and the aims of the tests that will be performed with hardwood sawdust and other sorts of feedstocks. The tests are finalized to assess the technical-economic fesibility of the flash-pyrolysis process, a step necessary for the commercialisation of the technology.
Chapter
Many plant materials contain minor amounts, often only in the 100 ppm range, of complex compounds which may have a considerable present or potential application in biological or pharmaceutical areas. Extraction and concentration of these specialty chemicals by conventional technology can be a laborious and costly process. Examples are given in which fast fluid bed pyrolysis has been used in our research to obtain pyrolysis liquids considerably enriched in such compounds, even when they have very low volatilities. One example involves the recovery of an alkaloid from plant leaves. Another feedstock gives complex terpene-based compounds (taxanes) which can be precursors for synthesis of new antitumor agents, or that can be used as a potential plant fungicide. Additional examples of complex compounds obtained in significant yields in fast pyrolysis oils can be found in the high molecular weight lignin fragments, largely aromatic in character, which are a part of the “pyrolytic lignin” fraction of a pyrolysis oil; and in the anhydrosugar monomers, dimers and oligomers obtained from the carbohydrate fraction of biomass on fast pyrolysis. Some unique features, and some speculations on mechanisms, of such specialized pyrolytic processes are discussed.
Chapter
This paper presents the results obtained during the commissioning and first series of experiments of the EGEMIN entrained bed flash pyrolysis process. The feedstock used was as-received wood waste and at an average reactor temperature of about 510 °C. A bio-oil yield of 40% was obtained on a moisture-free basis. The charcoal and gas yields were 29 and 16% respectively while the balance was water. Elemental analysis of the products indicates the incomplete conversion of the char as well as a relatively high oxygen content in the bio-oil.
Chapter
IntroductionTechnical ApproachExperimentalResultsConclusions AcknowledgementsReferences
Article
This paper presents the results obtained in the characterization of two different pyrolysis oils, the first one produced by carbonization and the second by flash pyrolysis. Chemical and physical properties such as density, viscosity, elemental composition, char content, water content, solubility and heating value were first determined, then an in-depth chemical characterization was carried out by liquid-liquid fractionation. We present a diagram indicating the separation procedure to provide four fractions (acids, bases, polars and hydrocarbons). We also recuperated very polar molecules which were retained in the aqueous layer (“aqueous” fraction). Each fraction was subsequently analyzed by GC-MS and FTIR. The acidic fraction is the most abundant and contains essentially phenolic structure, nevertheless phenols are differently substituted in the two oils: alkyl and methoxy groups in the carbonization oil, methoxy, acidic, aldehydic and ketonic functions in the flash pyrolysis oil. The other fractions present a similar composition for the two oils. Basic fraction is always very small, some aromaticN-containing compounds were identified. The “polar” neutral fraction is also small and its characterization is very difficult. The hydrocarbon fraction is especially constituted of aromatics and cyclics, some aliphatics were also identified. The “aqueous” fraction contains mainly carboxylic esters, alcohols and ethers.
Article
Highly oxygenated, biomass-derived oils can be upgraded to high quality hydrocarbon fuels by catalytic hydrotreating. Pacific Northwest Laboratory has successfully converted both high-pressure liquefaction oils and low-pressure pyrolysis oils to a highly aromatic, gasoline boiling range fuel. These studies were conducted in a 1-liter, continuous-flow reactor system. Six different biomass-derived oils and one peat-derived oil have been tested.
Article
A handicap facing both the producer and the user of fast-pyrolysis oils is the lack of a description of these oils that is adequate for commercial applications. These oils are highly oxygenated and are relatively immiscible with petroleum oils. Under the current IEA Biomass Energy Agreement, the new Pyrolysis Activity (PYRA) has taken on the task of establishing a useful description of a series of pyrolysis oils. This series roughly parallels that of petroleum fuel oils already described, so that with as few changes as possible to the users’ equipment, a bio-oil could be used in place of the equivalent petroleum-derived oil. The specifications for biomass pyrolysis oils differ in the density, heating value, water content, and corrosiveness. These proposed specifications are presented for discussion by the biomass conversion community and feedback to the Pyrolysis Activity.
Chapter
The Liquefaction Group of the lEA Biomass Agreement has carefully studied and analyzed a thermochemical conversion process under development at the National Renewable Energy Laboratory (NREL, formerly the Solar Energy Research Institute). This process converts biomass to an aromatic gasoline product. Biomass is subjected to very rapid pyrolysis in a vortex reactor to maximize the formation of oil vapors. After the char is removed from the process stream, the oil vapors are immediately sent to a catalytic cracking reactor with ZSM-5 zeolite catalyst to form a mixture of aromatic gasoline and gaseous olefins. Subsequent processing recovers byproduct gaseous olefms and converts them to aromatic gasoline. The small amount of toxic benzene formed as an intermediate compound is alkylated to extinction to form relatively benign compounds with a higher octane, such as cumene. The narrow boiling range desired for tomorrow’s reformulated gasolines is maintained by recycling both the volatile light ends and the difficult-to-bum heavy ends to extinction. A gasoline with a very high blending octane is the primary product. It is expected that this product will command a premium price. The process features state-of-the-art energy-saving and waste-management techniques. Using a consistent and well documented approach, the technoeconomics of this process were determined for both a “present” case and a “potential” case. The difference between the product costs for these two cases serves as an incentive for further research and development (R&D).
Article
The bio-oil obtained from the fast pyrolysis of biomass has a high oxygen content. Ketones and aldehydes, carboxylic acids and esters, aliphatic and aromatic alcohols, and ethers have been detected in significant quantities. Because of the reactivity of oxygenated groups, the main problems of the oil are instability. Therefore study of the deoxygenation of bio-oil is needed. In the present work the mechanism of hydrodeoxygenation (HDO) of bio-oil in the presence of a cobalt molybdate catalyst was studied. Particularly, the effects of reaction time, temperature, and hydrogen pressure on the HDO activity were examined. On the experimental results, a kinetic model for HDO of bio-oil was proposed.
Article
In the context of alternative sources of energy, many routes have been explored for using biomass. Direct combustion remains the most energy efficient use of biomass but liquids, rather than solids or gases, are preferred. Liquids have many advantages: high energy density, easy storage, handling and transportation and flexibility of use. Nevertheless, these liquids present some unwanted characteristics such as high viscosity, acidity, particulates content and chemical instability. Some upgrading is necessary before utilisation, specially for feeding turbines or internal combustion engines. Three different types of upgrading can be envisioned: physical, chemical/catalytic and the recovery of chemicals. Physical methods such as those to improve viscosity, offer potentially low cost steps which can be applied when the oil is used as soon as produced. The more expensive chemical/catalytic processes offer long term stabilisation and a range of improvement extending to high quality products. This paper reviews the main characteristics of the flash pyrolysis oils, their influence during the utilisation step and the possible solution to overcome this situation. The most important upgrading methods, both physical and chemical/catalytic, are summarised.
Article
Preliminary experimentation passing fresh softwood pyrolysis vapors over a ZSM-5 containing catalyst has shown promise for the production of a gasoline consisting primarily of high octane, methylated benzenes. Stoichiometric considerations show that the upper limit on the gasoline yield is about 63 gallons per ton of dry feedstock, if the coke by-product yield is only 5% and the phenolic by-product yield is only 3%. This gasoline yield would represent 48% of the energy in the biomass feedstock.
Article
In the reported experiments, a continuous fluidized bed bench scale flash pyrolysis unit operating at atmospheric pressure and feed rates of about 15 g/h has been successfully designed and operated. A unique solids feeder capable of delivering constant low rates of biomass has been developed. Extensive pyrolysis tests with hybrid aspen-poplar sawdust (105-250 mu m) have been carried out to investigate the effects of temperature, particle size, pyrolysis atmosphere and wood pretreatment on yields of tar, organic liquids, gases and char. At optimum pyrolysis conditions high tar yields of up to 65% of the dry wood weight fuel are possible at residence times of less than one second. Refs.
Chapter
IntroductionMaterials and Methods Results and DiscussionConclusions References
Article
The theoretical yield of charcoal from biomass lies in the range 50-80% on a dry weight basis. In spite of the fact that mankind has been manufacturing charcoal for about 6000 years, traditional methods for charcoal production in developing countries realize yields of 20% or less, and modern industrial technology offers yields of only 25-37%. Moreover, reaction times for the batch process in an industrial kiln are typically 8 days. In this article we describe a practical method for manufacturing high-quality charcoal from biomass that realizes near-theoretical yields of 42-62% with a reaction time of about 15 min to 2 h, depending on the moisture content of the feed. Because of its high efficiency, this technology can help to reduce worldwide deforestation and pollution, while providing greater amounts of a desirable, renewable fuel and chemical resource to mankind.
Article
The conversion of biomass into bio-oil using fast pyrolysis technology is one of the most promising alternatives to convert biomass into liquid products. However, substituting bio-oil for conventional petroleum fuels directly may be problematic because of the high viscosity, high oxygen content, and strong thermal instability of bio-oil. The focus of the current research is decreasing the oxygen and polymerization precursor content of the obtained bio-oil to improve its thermal stability and heating value. Catalytic fast pyrolysis of corncob with different percentages (5, 10, 20, and 30% by volume) of fresh fluidized catalytic cracking (FCC) catalyst (FC) and spent FCC catalyst (SC) in bed materials was conducted in a fluidized bed. The effects of the catalysts on the pyrolysis product yields and chemical composition of the bio-oil were investigated. A greater catalyst percentage lead to a lower bio-oil yield, while a lower catalyst percentage lead to little change of the composition of the bio-oil. The best percentages of FC and SC were 10 and 20%, respectively. FC showed more catalytic activation in converting oxygen into CO, CO2, and H2O than SC, but the oil fraction yield with FC was remarkably lower than that with SC because of more coke formation. The gas chromatography/mass spectrometry (GC/MS) analysis of the collected liquid in the second condenser showed that the most likely polymerization precursors, such as 2-methoxy-phenol, 2-methoxy-4-methyl-phenol, 4-ethyl-2-methoxy-phenol, 2-methoxy-4-vinylphenol, and 2,6-dimethoxy-phenol decreased, while monofunctional phenols, ketones, and furans increased compared to that in the noncatalytic experiment. The hydrocarbons increased with the increase of the catalyst percentages, and this contributed to the decrease of the oxygen content of the bio-oil. Multi-stage condensation achieved a good separation of the oil fraction and water.