Journal of Sustainable Bioenergy Systems

To investigate the genetic diversity and relationships among the sweet sorghum varieties as energy sources currently bred in China, 13 sweet sorghum varieties were selected for comprehensive analysis through observations of 31 biological traits and examinations of RAPD and SSR molecular markers. The numerical analysis showed that the differences in biological traits existed among 13 varieties, and the genetic distance (DIST) ranged from 0.787 to 2.221, and the two varieties from Inner Mongolia and Xinjiang were distinctly separated from all other varieties. A total of 22 polymorphism primers were obtained from the screening using RAPD marker analysis. The polymorphism rate was 58.33%, and the genetic similarity (GS) coefficients among the studied cultivars ranged from 0.694 to 0.896. Cluster analysis results indicated that the three varieties from Inner Mongolia, Xinjiang and Heilongjiang exhibited significant genetic differences from the other varieties. SSR marker analysis using 31 selected pairs of polymorphic primers showed that the polymorphism rate of amplified fragments was 78.64%, and GS coefficients among the tested cultivars were 0.534 to 0.971. Cluster analysis showed that variety No. 12 from Xinjiang and variety No. 7 from Inner Mongolia clustered into one group, and variety No. 6 from Heilongjiang was in a single group. The other ten varieties were grouped into another separate cluster. The results based on combined data displayed a similar trend with results from the three individual data analyses, but could more comprehensively and objectively reflect the fundamental genetic differences among these varieties. In summary, certain genetic differences exist among the varieties tested from different regions or different breeding institutions. However, varieties from the same region, especially those from the same breeding institution, exhibited small genetic variations and high genetic similarities. At present, more attention should be paid to discovery and innovation in the breeding of sweet sorghum varieties.

The fungal endophyte, Ascocoryne sarcoides, produced aviation, gasoline and diesel-relevant hydrocarbons when grown on multiple substrates including cellulose as the sole carbon source. Substrate, growth stage, culturing pH, temperature and medium composition were statistically significant factors for the type and quantity of hydrocarbons produced. Gasoline range (C_5-C_(12)), aviation range (C_8-C_(16)) and diesel range (C_9-C_(36)) organics were detected in all cultured media. Numerous non-oxygenated hydrocarbons were produced such as isopentane, 3,3-dimethyl hexane and d-limonene during exponential growth phase. Growth on cellulose at 23˚C and pH 5.8 produced the highest overall yield of fuel range organics (105 mg * g•biomass^(-1)). A change in metabolism was seen in late stationary phase from catabolism of cellulose to potential oxidation of hydrocarbons resulting in the production of more oxygenated compounds with longer carbon chain length and fewer fuel-related compounds. The results outline rational strategies for controlling the composition of the fuel-like compounds by changing culturing parameters.

The paper discusses the features of the Biomass Boiler drum water level. Conventional PID Control System can not reach a satisfaction result in nonlinearity and time different from Biomass Boiler Drum Water Control System. In this study, a kind of fuzzy self-adaptive PID controller is described and this controller is used in biomass boiler’s drum water level control system. Using the simulink tool of MATLAB simulation software to simulate the fuzzy adaptive PID and conventional PID control system, the result of the comparison shows that the fuzzy self-adaptive PID has the strong anti-jamming, flexibility and adaptability as well as the higher control precision in Biomass Boiler Drum Water.

Rice paddy-field microbial fuel cells (RPF-MFCs) are devices that exploit rhizosphere bacteria to generate electricity from soil organic matter, including those excreted from roots. Previous studies have examined factors affecting electric outputs from RPF-MFCs and demonstrated that RPFMFC was able to generate electricity up to 80 mW·m-2 (based on the projected area of anode). The present study operated RPF-MFCs with different sizes of anodes and cathodes and examined how electrode sizes affected electricity generation. We show that anodes are the limiting factor for electricity generation immediately after commencing the operation, while cathodes become the limiting factor after anode performances are sufficiently increased. RPF-MFC achieved the maximum power density of 140 mW·m-2 (based on the projected area of anode), when the cathode is sufficiently larger than the anode. Results suggest that the cathode needs to be improved for eliciting the maximum capacity of rhizosphere bacteria for electricity generation in RPF-MFC.

This work investigated the effect of two organic binders’ low rate on energy efficiency of Briquettes produced from charcoals of Tender Coconut Husks, Palm Kernel Shells and Corn Cobs. Bombax Costatum calyx and Cissus Repensbarks were used separately as binders to elaborate briquettes. The briquettes were compared based on their energy efficiency parameters with wood charcoal as control.

This article reports a high yielding technique of synthesizing zirconium dodecyl sulphate (“ZDS”) for in situ transesterification of Nannochloropsis occulata and Chlorella vulgaris for fatty acid methyl ester (FAME) production. ZDS produced a significantly higher FAME yield in N. occulata than in C. vulgaris (p = 0.008). The varying performance of ZDS in the two species could be due to their different cell wall chemistries. Sodium dodecyl sulphate (SDS) in H2SO4 for FAME enhancement from the two species was also studied. Treatment with SDS in H2SO4 increased the FAME production rate in both species. Residual protein content after the in situ transesterification in C. vulgaris and N. occulata reduced respectively by 6.5% and 10%. The carbohydrate content was reduced by 71% in C. vulgaris and 65% in N. occulata. The water tolerance of the process when using H2SO4, with or without SDS, was evaluated by hydrating the two species with 10% - 30% distilled water (w/w dry algae). The FAME concentration began to diminish only at 30% water content in both species. Furthermore, the presence of a small amount of water in the biomass or methanol increased the lipid extraction efficiency, improving the FAME yield, rather than inhibiting the reaction.

Abstract Rising greenhouse gas emissions are causing climate change, and the world’s focus has shifted to the need to reduce our reliance on fossil fuels. There has been a rise in the published literature on the utilization of crops for bioenergy production in Louisiana. However, very few scholarly documents have used Geographic Information Systems (GIS) to map the distribution of potential bioenergy crops in Louisiana. This study seeks to fill the void by evaluating the potential of bioenergy crops in Louisiana for energy production using GIS. Given this objective, the agricultural census data for 1999, 2009, 2019, and 2020 obtained from the U.S. Department of Agriculture were used in the analysis. The quantities of various crops produced in the state were loaded into an attribute table and joined to a shapefile using ArcGIS software. The symbology tool’s graduated option was used to create five maps representing each of the bioenergy crops in Louisiana. The findings of the GIS analysis show that some of the parishes, such as Franklin produced the most bushels of corn (13,795,416), Iberia produced the most tons of sugarcane (1,697,980), East Carroll produced the most bushels of soybean (8,237,991), Tensas harvested the most bales of cotton (80,898) and Avoyelles produced the most bushels of sorghum (630,694). The abundance and availability of crops as raw materials for energy production will translate into lower prices in terms of energy use, making bioenergy crops a promising alternative to fossil fuels. In addition, gasoline price data from 1993-2022 was obtained from U.S. Energy Information Administration. A regression model for the average annual gasoline price over the years was constructed. The results show that the average annual gasoline price variation with respect to years is statistically significant (p < 0.05). This suggests that gasoline prices will generally rise despite a price drop over the years. The paper concludes by outlining policy recommendations in the form of assessing the availability and viability of other crop types, such as wheat, oats, and rice, for energy production in the state. Keywords Bioenergy Crops, Biomass, Fossil Fuel, Gasoline, Geographic Information Sys-tem (GIS), Regression Analysis, Louisiana

The aim of this paper was to compare the annual economic impact of a large-scale bio-coal pellet plant by raw material specifically for the Finnish Lakeland region. In this study, the total production volume of the theoretical plant was 200,000 tons per year and the raw wood materials used were birch pulpwood, spruce pulpwood, pine pulpwood, and energy wood. These wood materials were young delimbed wood from early thinnings. The main goal of the paper was to illustrate that the energy content differences of raw wood materials affect the economic profitability of a bio-coal pellet plant at regional level. In this case, wood type also has a regional economic impact, which the pellet plant can influence through its raw wood material choices. The raw material comparison was based on measured data and not computational or literary data alone. The study found that lower solid wood energy densities caused higher relative costs for the total supply chain. A parallel phenomenon occurred with the required gross margin of the pellets, where lower energy content caused higher required gross margin for pellet sales. The gross margin was also sensitivity analyzed at different discount rates from 5% to 20%. At each required discount rate, the highest annual economic impact on the region was found for birch pellets, with values of 36.95 - 42.66 million €. Spruce pellets had the smallest annual economic impact, although it had the highest final pellet price in the same cases. The different economic effects were caused by the energy volumes sold.

Napiegrass (Pennisetum purpureum Schumach) was treated with a low-moisture anhydrous ammonia (LMAA) pre-treatment by adding an equal weight of water and keeping it under atmospheric ammonia gas at room temperature for four weeks. After the removal of ammonia and washing with water, a simultaneous saccharification and fermentation (SSF) was conducted for the LMAA-pretreated napiergrass (1.33 g) in a buffer solution (8 mL) using a mixture of a cellulase (80 mg) and a xylanase (53 mg) as well as the cell suspension (0.16 mL) of Saccharomyces cerevisiae. Etha-nol and xylose resulted in 91.2% and 62.9% yields, respectively. The SSF process was scaled up using LMAA-pre-treated napiergrass (100.0 g) to give ethanol (77.2%) and xylose (52.8%). After the removal of ethanol, the pentose fermentation of the SSF solution (40 mL), which contained 1.00 g of xylose, using cell suspension of Escherichia coli KO11 (70 mL) gave 86.3% yield of ethanol. Total ethanol yield reached 68.9% based on xylan (21.4 wt%) and glucan (39.7 wt%) of the LMAA-pretreated napiergrass.

Recently microbial fuel cells (MFCs) have been considered as an alternative power generation technique by utilizing organic wastes. In this study, an experiment was carried out to generate bioelectricity from co-digestion of organic waste (kitchen waste) and sewage sludge as a waste management option using microbial fuel cell (MFC) in anaerobic process. A total of five samples with different sludge-waste ratio were used with zinc (Zn) and cupper (Cu) as cell electrodes for the test. The trends of voltage generation were different for each sample in cells such as 350 mV, 263 mV, 416 mV maximum voltage were measured from sample I, II and III respectively. It was observed that the MFC with sewage sludge showed the higher values (around 960 mV) of voltages with time whereas 918 mV obtained with organic waste. Precisely comparing cases with varying the organic waste and sewage sludge ratio helps to find the best bioelectricity generation option. Using MFCs can be appeared as the solution of electricity scarcity along the world as an efficient and eco-friendly manner as well as organic solid waste and sewage sludge management.

The aim of this work was to use fish processing waste (FW) as main substrate for anaerobic digestion. To enhance the biogas production of FW, co-digestion was done with two other substrates: cow dung (CD) and waste of market (MW). Batch test was carried out in an 1 L glass digester in a temperature controlled chamber at 38˚C. The following mixtures were carried out: FW with CD respectively at different ratios 100:0% (A), 80:20% (B) and 60:40% (C); FW with MW at the following ratio 80:20% (D); FW with CD and MW respectively at these ratios 80:10:10% (F) and 60:20:20% (G). The biogas produced was measured using a milligas counter® and the volume of gas was recorded. The gas composition was determined using gas chromatography. With a pH stable for raw substrates and mixtures, TS and VS (%TS) contents for FW were respectively 31.01% and 91.55%. Between 3 to 13 days of experimentation, the highest flow rate was observed. The percentage of methane was more important for mixtures B and D, 61% and 59% respectively. pH and VOA/TIC were stable at the end of the batch test for all mixtures, meaning that the organic matter was already well digested. The highest values of Volatile Solid Removal (VSR) were found for mixtures C, D, F and G. Therefore, the promising mixtures for next experimentations in large scale are B and D.

The potential of biodiesel fuels from various vegetable oil sources such as sunflower (SFME), saf-flower (SAFME), peanut (PME) and canola (CME) as well as from low-cost chicken fat (CFME) to supplement increasing biodiesel demands must be evaluated in terms of the corresponding engine performance and exhaust emissions. In this study, two diesel engines rated at 14.2 kW (small) and 60 kW (large) were operated by using the different biodiesel fuels and a reference diesel. Results showed that both the small and large engines delivered similar power when using biodiesel fuels in the expense of higher brake-specific fuel consumptions (BSFC). Higher exhaust concentrations of nitrogen oxides (NOx) and carbon dioxide (CO 2) while lower carbon dioxide (CO) and negligible sulfur dioxide (SO 2) emissions were observed in both engines. Total hydrocarbon emissions (THC) were higher in both engines when using SME, SFME and CME but comparable when using CFME, SAFME and PME in the large engine. Thus, with the increasing demand for biodiesel, alternative feedstock sources such as those used in this study may be utilized to take advantage of their availability, renewability and environmental benefits.

The packed bed solid state bioreactor designated as PBSSB is constructed in the present study. The experiments are carried out in packed bed bioreactor with jowar straw and inoculated with Aspergillus oryzae. Temperature gradient has been measured at different axial positions. It is found that the organisms grew rapidly during the period from 20 to 30 h during which heat generation is more. These results are in agreement with other researchers. The fermented jowar straw shows threefold increase in protein content. This can be utilized as high value nutritional feed to animals.

The concern on climate change and on the limitations of fossil fuels is leading to the promotion of renewable-based energy options. However, the assessment of the energy profitability of a technology is still a controversial topic, especially when renewable-based systems are compared with non-renewable ones and when the depletion of the stocks of available resources is not accounted properly. As a matter of fact, some popular energy indicators do not seem to cover all the aspects of the problem, with the risk of drawing ambiguous conclusions. A set of life cycle-based indicators is proposed in order to establish a more reliable approach to the assessment of energy products which decouples the different contributions given by renewable and non-renewable resources. The proposed set of indicators has been quantified for different groups of energy products and compared with an energy indicator frequently used (i.e. EROI). A coherent assessment of the depletion of energy resources and of the energy profitability of the products is presented. The indicators could even contribute to understand the feasibility of energy projects and plans by evaluating their impact on the stock of energy resources.

This study proposed using waste frying oil rather than refined vegetable oil as an effective way to reduce the raw material cost of producing biodiesel. In addition, the ultrasonic-assisted two-step catalyzing Process was first adopted for the production of biodiesel from waste frying oil. The results show that the total reaction time was less than 50 min and the conversion rate of fatty acid methyl esters (FAMEs) achieved was 97.1%. Therefore, the ultrasonic-assisted two-step catalyzing process has a potential application in producing biodiesel from waste frying oil.

This study proposed using waste frying oil rather than refined vegetable oil as an effective way to reduce the raw material cost of producing biodiesel. In addition, the ultrasonic-assisted two-step catalyzing Process was first adopted for the production of biodiesel from waste frying oil. The results show that the total reaction time was less than 50 min and the conversion rate of fatty acid methyl esters (FAMEs) achieved was 97.1%. Therefore, the ultrasonic-assisted two-step catalyzing process has a potential application in producing biodiesel from waste frying oil.

This work investigated the bio-oil production from oil palm empty fruit bunch (EFB) by continuous pyrolysis reactor under nitrogen and steam atmospheres as sweeping gas. The study parameters were particle size, biomass feeding rate, reactor temperature, and reactor sweeping gas. The EFB particle ranges were below 500 micrometers, between 500 - 1180 micrometers and 1180 - 2230 micrometers. Feeding rates were 150, 350, and 550 rpm. Both factors were analyzed by single factor ANOVA. Additionally, Box-Behnken design was used to investigate temperature (350oC - 600oC) under the following nitrogen and steam flow rates as sweeping gas: 0, 100, and 200 cm3/min of nitrogen and 0, 9, and 18 cm3/min of steam. The mathematical model from Box-Behnken design succeeded in predicting the optimal conditions for normal and nitrogen atmospheres. A particle size below 1180 μm was determined to be optimal for bio-oil production. In a normal atmosphere or no sweeping gas, the condition was 475oC and 450 rpm of feed rate. The optimal condition for nitrogen atmosphere was 530oC, 450 rpm of feed rate, and 200 cm3/min of nitrogen flow rate. However, steam as sweeping gas caused high uncertainty and the model was unable to predict the optimal conditions accurately. The biooils from normal, nitrogen, steam, and mixed atmospheres were analyzed for general characteristics. NMR and GC-MS were used to analyze chemical compositions in the bio-oils. Relationships between physical and chemical characteristics were determined and discussed.

Fluidized bed superheated steam drying is one of the technologies successfully applied to drying pulp in the sugar beet industry. It has the technological advantages of energy efficiency and safety (inert environment) required for use in drying bagasse. A comparison of the particle size distribution of bagasse and beet pulp was evaluated in terms of flu-idization. The size distribution of bagasse particles is from 2 to 10 times broader than the equivalent distribution of beet pulp particles. The mean particle size of the bagasse is 1/3 of the mean size of the beet pulp. Fluidization tests proved that bagasse fluidization is possible. It was found that beet pulp and bagasse particles clearly differ on shape and size distribution which in turn will affect the design of the ancillary equipment and the fluidization systems if sugarcane bagasse is to be dried using superheated steam technology.

All EU countries have targets for increasing the use of renewable energy at a national level. However this effort should become concrete at regional and local levels where investments on bioenergy are made. This study introduces a systematical and universally applicable method for constructing regional energy balance. This study focuses on the method how to combine specific regional primary energy sources with their end uses. The primary energy sources include different fuels and the net import of electricity. The energy end uses are heat, electricity and losses. The concept of the regional energy balance was illustrated through a case of South Karelia. The total use of primary energy in South Karelia was 25.2 TWh (or 91 PJ) in 2010 and the share of renewable energy sources was 65%. The regional energy balance analysis can be utilized as a guideline for strategically planning and allocating regional energy sources for example, increasing the use of renewable energy sources. It can provide local decision makers and shareholders about the current status of energy supply, convincing them to take proper actions and consider producing energy at a local and regional level.

This study examined the effects of soil and switchgrass variety on sustainability and eco-friendliness of switchgrass-based ethanol production. Using the Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model, switchgrass biomass yields were simulated for several scenarios of soils and varieties. The yields were fed to the Integrated Biomass Supply Analysis and Logistics (IBSAL) model to compute energy use and carbon emissions in the biomass supply chain, which then were used to compute Net Energy Value (NEV) and Carbon Credit Balance (CCB), the indicators of sustainability and eco-friendliness, respectively. The results showed that the values of these indicators increased in the direction of heavier to lighter soils and on the order of north-upland, south-upland, north-lowland, and south-lowland varieties. The values of NEV and CCB increased in the direction of dry to wet year. Gaps among the varieties were smaller in a dry year than in a wet year. From south to north, NEV and CCB decreased for lowland varieties but increased for upland ones. Thus, the differences among the varieties decreased in the direction of lower to higher latitudes. The study demonstrated that the sustainability and eco-friendliness of switchgrass-based ethanol production could be increased with alternative soil and variety options.

Bamboo, with its advantages of fast growth, short renovation, easy propagation and rich in cellulose and hemicellulose, is a potential feedstock for bioethanol or other biofuels production. The objective of this study was to examine the fea-sibility of microwave assistant KOH pretreatments to enhance enzymatic hydrolysis of bamboo. Pretreatment was car-ried out by immersing the bamboo in KOH (12% and 8% w/w bamboo) solutions and exposing the slurry to microwave radiation power of 400 W for 30min. Chemical composition of the pretreated substrates and spent liquor was analyzed. Pretreated substrates were enzymatic hydrolyzed, and glucose and xylose in the hydrolysate were analyzed. The results showed that the pretreated substrate with microwave assisted KOH had significantly higher sugar yield than the un-treated samples. The fermentation inhibitors formic acid, furfural, HMF and levulinic acid were much lower than acid pretreatment reported.

Biomass gasification is a thermochemical conversion process that dates back to the 19th century. Nevertheless, designing and operating a gasifier system is not an easy task. Every biomass feedstock has different characteristics and the gasifier needs to be designed according to those qualities. Hence, many laboratory analyses on bamboo were carried out for this study. This study also concentrates on finding the best possible process variables for a bamboo fueled downdraft gasifier through a sensitivity analysis. A software program called Thermoflex was used for this purpose and the effect of gasifier temperature, air-fuel-ratio, moisture content of the fuel and temperature of pre-heated air on the syngas composition were simulated. The results show that bamboo is a decent gasification feedstock because of its low ash and sulfur content and satisfactory energy value. The simulations reveal that the best gas quality is obtained with the gasifier temperature between 700℃ and 800℃, A/F-ratio of 1.25 - 1.75 and dry basis moisture content between 10% and 15%.

The aim of this paper is to review the articles corresponding to the potentiality of biodiesel generation in Bangladesh. Many researchers gave their opinions and results related to their experiments for producing bio-fuel in Bangladesh. The potentiality of biofuel from different edible sources like mustard oil, coconut oil, sesame oil, mosna oil, soybean oil etc. and different non-edible sources like castor oil, rice bran oil, Jatropha curcas oil, karanja oil, microalgae oil, rubber seed oil, neem oil, linseed oil etc. are studied here. The properties and the uses of biofuels in diesel engine and their performances are also reviewed in this paper. The emission characteristics are reviewed and investigated too. Moreover, the cost analysis of biofuel compared to the other fuels is inspected here. All types of research related to biofuel are thoroughly reviewed. The main and important challenges to use biofuel and their solutions are given by authors in this research article. This paper presents the scopes of applying technologies to improve the sustainability of bio-fuel in respect of Bangladesh.

In order to reduce the emission of NO x , SO x , and CO 2 and mitigate the dependence on the fossil fuel, the use of renewable energy, especially the biomass energy, has been explored. Since most biomass fuels are hard to grind to the very fine size, gasification is the preferred technology of energy conversion. Updraft fixed bed gasification using partial oxidation process is adopted where air less than the stoichiometric quantity is admitted to oxidize the char to CO. The temperature profile within the bed reveals a characteristic temperature peak. The results reveal a correlation between the higher heating value (HHV) of producer gas and the peak gasification temperature (T peak). Coal with higher char content (~45%) is blended with biomass of low char content (~20%) in order to produce high quality gas. In this study, the Texas-based mesquite fuel was blended with Wyoming Power River Basin (PRB) coal with mass ratios of 100:0, 90:10, and 80:20 and fired downward into the gasifier. It was found that at a given mesquite to the coal mass ratio, the peak gasification temperature decreased with the increase in ER. With the increase of the coal ratio in the mesquite: coal blend and the peak temperature increased significantly; more combustible gases such as CO, CH 4 were generated at the end of product gas, and the HHV of the product gas increased by 10%-20%.