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Purpose Diminishing fossil resources and environmental concerns associated with their vast utilization have been in focus by energy policy makers and researchers. Among the different scenarios put forth to commercialize biofuels, various biorefinery concepts have aroused global interests because of their ability in converting biomass into a spectrum of marketable products and bioenergies. This study was aimed at developing different novel castor-based biorefinery scenarios for generating biodiesel and other co-products, i.e., ethanol and biogas. In these scenarios, glycerin, heat, and electricity were also considered as byproducts. Developed scenarios were also compared with a fossil reference system delivering the same amount of energy through the combustion of neat diesel. Materials and methods Life cycle assessment (LCA) was used to investigate the environmental consequences of castor biodiesel production and consumption with a biorefinery approach. All the input and output flows from the cultivation stage to the combustion in diesel engines as well as changes in soil organic carbon (SOC) were taken into account. Impact 2002+ method was used to quantify the environmental consequences. Results and discussion The LCA results demonstrated that in comparison with the fossil reference system, only one scenario (i.e., Sc-3 with co-production of significant amounts of biodiesel and biomethane) had 16% lower GHG emissions without even considering the improving effect of SOC. Moreover, resource damage category of this scenario was 50% lower than that of neat diesel combustion. The results proved that from a life cycle perspective, energy should be given priority in biorefineries because it is essential for a biorefinery to have a positive energy balance in order to be considered as a sustainable source of energy. Despite a positive effect on energy and GHG balances, these biorefineries had negative environmental impacts on the other damage categories like Human Health and Ecosystem Quality. Conclusions Although biorefineries offer unique features as promising solutions for mitigating climate change and reducing dependence on fossil fuels, the selection of biomass processing options and management decisions can affect the final results in terms of environmental evaluations and energy balance. Moreover, if biorefineries are focused on transportation fuel production, a great deal of effort should still be made to have better environmental performance in Human Health and Ecosystem Quality damage categories. This study highly recommends that future studies focus towards biomass processing options and process optimization to guarantee the future of the most sustainable biofuels.
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LCA FOR ENERGY SYSTEMS AND FOOD PRODUCTS
Life cycle assessment of castor-based biorefinery: a well
to wheel LCA
Benyamin Khoshnevisan
1
&Shahin Rafiee
1
&Meisam Tabatabaei
2,3
&
Hossein Ghanavati
2,3
&Seyed Saeid Mohtasebi
1
&Vajiheh Rahimi
4
&Marzieh Shafiei
5
&
Irini Angelidaki
6
&Keikhosro Karimi
4,7
Received: 19 January 2017 /Accepted: 27 July 2017 /Published online: 21 September 2017
#Springer-Verlag GmbH Germany 2017
Abstract
Purpose Diminishing fossil resources and environmental con-
cerns associated with their vast utilization have been in focus by
energy policy makers and researchers. Among the different
scenarios put forth to commercialize biofuels, various
biorefinery concepts have aroused global interests because of
their ability in converting biomass into a spectrum of market-
able products and bioenergies. This study was aimed at devel-
oping different novel castor-based biorefinery scenarios for
generating biodiesel and other co-products, i.e., ethanol and
biogas. In these scenarios, glycerin, heat, and electricity were
also considered as byproducts. Developed scenarios were also
compared with a fossil reference system delivering the same
amount of energy through the combustion of neat diesel.
Materials and methods Life cycle assessment (LCA) was used
to investigate the environmental consequences of castor biodiesel
production and consumption with a biorefinery approach. All the
input and output flows from the cultivation stage to the combus-
tion in diesel engines as well as changes in soil organic carbon
(SOC) were taken into account. Impact 2002+ method was used
to quantify the environmental consequences.
Results and discussion The LCA results demonstrated that in
comparison with the fossil reference system, only one scenario
(i.e., Sc-3 with co-production of significant amounts of biodiesel
and biomethane) had 16% lower GHG emissions without even
considering the improving effect of SOC. Moreover, resource
damage category of this scenario was 50% lower than that of
neat diesel combustion. The results proved that from a life cycle
perspective, energy should be given priority in biorefineries
because it is essential for a biorefinery to have a positive energy
balance in order to be considered as a sustainable source of
energy. Despite a positive effect on energy and GHG balances,
Responsible editor: Yi Yang
Electronic supplementary material The online version of this article
(https://doi.org/10.1007/s11367-017-1383-y) contains supplementary
material, which is available to authorized users.
*Shahin Rafiee
shahinrafiee@ut.ac.ir
*Meisam Tabatabaei
Meisam_tab@yahoo.com; meisam_tabatabaei@abrii.ac.ir
*Marzieh Shafiei
m.shafiei@eng.ui.ac.ir
1
Department of Mechanical Engineering of Agricultural Machinery,
Faculty of Agricultural Engineering and Technology, College of
Agriculture and Natural Resources, University of Tehran, Karaj, Iran
2
Microbial Biotechnology Department, Agricultural Biotechnology
Research Institute of Iran (ABRII), Agricultural Research, Education
and Extension Organization (AREEO), P.O. Box 31535-1897,
Karaj, Iran
3
Biofuel Research Team (BRTeam), Karaj, Iran
4
Department of Chemical Engineering, Isfahan University of
Technology, Isfahan 84156-83111, Iran
5
Department of Chemical Engineering, Faculty of Engineering,
University of Isfahan, Isfahan 81746-73441, Iran
6
Department of Environmental Engineering, Technical University of
Denmark, 2800 Kgs Lyngby, Denmark
7
Industrial Biotechnology Group, Institute of Biotechnology and
Bioengineering, Isfahan University of Technology,
Isfahan 84156-83111, Iran
Int J Life Cycle Assess (2018) 23:17881805
DOI 10.1007/s11367-017-1383-y
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Merck ethanol absolute was used in this study. Nine different blends of biodiesel (5, 10, and 15 v/v%), ethanol (2,4, and 6 v/v%), and neat diesel were used in the experiments (Table 1). Blends prepared at 6-L container for each blend. ...
... Accordingly, the study covered the extraction of raw materials, the production of chemicals and materials, all agricultural activities to produce biomass for ethanol and biodiesel production, transportation, biofuel production, and combustion stage. To increase the economic and environmentally feasibility of castor biodiesel production, the production of castor biodiesel was assumed to follow the biorefinery approach proposed by Khoshnevisan et al. 2 The system boundary is shown in Figure 3a. ...
... 38 Castor production and processing constitute an important part of diestrol supply chain. Following the study of F I G U R E 2 (a) HBMO adopted for diesel engine optimization, (b) the topology of the proposed ANFIS model Khoshnevisan et al. 2 and in order to avoid conflicts with agricultural crop production, marginal lands were assumed to be used for castor production. ...
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... There are reports on its potential use as fish feed [101], fertilizer [102], an absorbent for removal of textile dyes [103], in addition to other possibilities [83]. There have been experimental studies on the hydroprocessing of castor oil to produce jet fuel [104,105], and multiple references on castor-based biodiesel including the GHG emissions associated with its production [106][107][108][109]. Only recently, life cycle GHG emissions from castor-HEFA production in north-east China was reported to range between 41 and 78 gCO 2 e/MJ SAF depending on different planting conditions [95]. ...
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... Thus, fossil fuel production still needs to be optimized by exploring new subsurface storage and optimizing current natural resource lifting. Fossil fuel dependence has resulted in two significant challenges, a decline in resource supply and environmental pollution (Khoshnevisan et al., 2018). Therefore, optimizing current natural resource lifting with a sustainable production and environment approach is needed national medium-term fossil fuel production aim. ...
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... Lardon et al. (2009) reported the LCA of biodiesel production from microalgae, where a comparative LCA study was undertaken to assess the energetic balance and the potential environmental impact of the whole process chain, from the biomass production to the biodiesel combustion. In the goal and scope definition, the well-to-wheel, well-to-gate, cradle-to-gate, cradle-to-grave, etc., are some of the system boundary considerations in the LCA of biodiesel (Dufour and Iribarren, 2012;Fernandez et al., 2016;Khoshnevisan et al., 2018;Liu et al., 2018c;Khounani et al., 2021). The functional unit consideration for LCA of biodiesel is reported to be 1000 kg of biodiesel, 1 MJ of biodiesel, etc. (Dufour and Iribarren, 2012;Fernandez et al., 2016;Liu et al., 2018c;Al-Muhtaseb et al., 2021). ...
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Diminishing fuel resources and stringent emission mandates have demanded cleaner combustion and increased fuel efficiency. Three water addition rates, i.e., 2, 4, and 6 wt.% in biodiesel-diesel blend (B5) was investigated herein. Combustion characteristics of the emulsified fuel blends were compared in a naturally-aspirated diesel engine at full load and different engine speeds. More specifically, biodiesel was produced from waste cooking oil (WCO) and to further increase waste utilization, recycled biodiesel wastewater was used as additive in B5. The result obtained showed that low-level water addition (i.e., 2 and 4 wt.%) in B5 led to different results from those obtained using higher water addition rates (i.e., >5 wt.%) reported by the previous studies. In more details, the findings of the present study revealed that low level water addition in B5 could considerably reduce CO, HC, CO2, and NOx emissions. Among water-containing B5 fuel emulsions, the optimal water addition level in terms of engine performance parameters and emissions was found at 4 wt.%. In particular, the emitted CO2, HC, and NOx were decreased by over 8.5%, 28%, and 24%, respectively, at maximum speed of 2500 rpm.
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Depletion of fossil fuel resources and stringent emission mandates has spurred the search for improved diesel engines performance and cleaner combustion. One of the best approaches to solve these issues is to use biodiesel/diesel additives. The effects of biodiesel/diesel additives on the performance and emissions of diesel engines were comprehensively reviewed throughout this article. The additives reviewed herein were classified into five categories, i.e., oxygenated additives, metallic and non-metallic based additives, water, antioxidants, and polymeric-based additives. The effects of each category on the engine performance (i.e., brake specific fuel consumption (bsfc) and brake thermal efficiency (bte)) and emissions (i.e., CO, NOx, HC, and PM) were exclusively summarized and discussed. Furthermore, various strategies used for adding water like water-diesel emulsion, direct water injection, and adding water into the inlet manifold were illustrated and their pros and cons were completely scrutinized. Finally, opportunities and limitations of each additive considering both engine performance and combustion benignity were outlined to guide future research and development in the domain.