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Title: Life-Cycle Analysis of Greenhouse Gas Emissions and Water Consumption – Effects of Coal and Biomass Conversion to Liquid Fuels as Analyzed with the GREET Model

Abstract

The vast reserves of coal in the U.S. provide a significant incentive for the development of processes for coal conversion to liquid fuels (CTL). Also, CTL using domestic coal can help move the U.S. toward greater energy independence and security. However, current conversion technologies are less economically competitive and generate greater greenhouse gas (GHG) emissions than production of petroleum fuels. Altex Technologies Corporation (Altex, hereinafter) and Pennsylvania State University have developed a hybrid technology to produce jet fuel from a feedstock blend of coal and biomass. Collaborating with Altex, Argonne National Laboratory has expanded and used the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model to assess the life-cycle GHG emissions and water consumption of this hybrid technology. Biomass feedstocks include corn stover, switchgrass, and wheat straw. The option of biomass densification (bales to pellets) is also evaluated in this study. The results show that the densification process generates additional GHG emissions as a result of additional biomass process energy demand. This process coproduces a large amount of char, and this study investigates two scenarios to treat char: landfill disposal (Char-LF) and combustion for combined heat and power (CHP). Since the CHP scenarios export excess heat andmore » electricity as coproducts, two coproduct handling methods are used for well-to-wake (WTWa) analysis: displacement (Char-CHP-Disp) and energy allocation (Char-CHP-EnAllo). When the feedstock contains 15 wt% densified wheat straw and 85 wt% lignite coal, WTWa GHG emissions of the coal-and-biomass-to-liquid pathways are 116, 97, and 137 gCO2e per megajoule (MJ) under the Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo scenarios, respectively, as compared to conventional jet fuel production at 84 gCO2e/MJ. WTWa water consumption values are 0.072, -0.046, and 0.044 gal/MJ for Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo, respectively, as compared to conventional jet fuel production at 0.028 gal/MJ. To reach the break-even point of 84 gCO2e/MJ, under the assumptions of constant product yields and energy demands regardless of the share of biomass and coal feedstocks, 31 wt%, 23 wt%, and 53 wt% of the feedstock blend need to be biomass under the Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo scenarios, respectively.« less

Authors:
 [1];  [1];  [1]
  1. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
Altex Technologies Corporation, Sunnyvale, CA (United States)
OSTI Identifier:
1372111
Report Number(s):
ANL/ESD-17/14
136627
DOE Contract Number:
AC02-06CH11357
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 54 ENVIRONMENTAL SCIENCES; combined coal and biomass conversion to liquid fuels (CBTL); greenhouse gas (GHG) emissions; life-cycle analysis (LCA); water use; well-to-wake (WTWa) analysis

Citation Formats

Li, Qianfeng, Cai, Hao, and Han, Jeongwoo. Life-Cycle Analysis of Greenhouse Gas Emissions and Water Consumption – Effects of Coal and Biomass Conversion to Liquid Fuels as Analyzed with the GREET Model. United States: N. p., 2017. Web. doi:10.2172/1372111.
Li, Qianfeng, Cai, Hao, & Han, Jeongwoo. Life-Cycle Analysis of Greenhouse Gas Emissions and Water Consumption – Effects of Coal and Biomass Conversion to Liquid Fuels as Analyzed with the GREET Model. United States. doi:10.2172/1372111.
Li, Qianfeng, Cai, Hao, and Han, Jeongwoo. Thu . "Life-Cycle Analysis of Greenhouse Gas Emissions and Water Consumption – Effects of Coal and Biomass Conversion to Liquid Fuels as Analyzed with the GREET Model". United States. doi:10.2172/1372111. https://www.osti.gov/servlets/purl/1372111.
@article{osti_1372111,
title = {Life-Cycle Analysis of Greenhouse Gas Emissions and Water Consumption – Effects of Coal and Biomass Conversion to Liquid Fuels as Analyzed with the GREET Model},
author = {Li, Qianfeng and Cai, Hao and Han, Jeongwoo},
abstractNote = {The vast reserves of coal in the U.S. provide a significant incentive for the development of processes for coal conversion to liquid fuels (CTL). Also, CTL using domestic coal can help move the U.S. toward greater energy independence and security. However, current conversion technologies are less economically competitive and generate greater greenhouse gas (GHG) emissions than production of petroleum fuels. Altex Technologies Corporation (Altex, hereinafter) and Pennsylvania State University have developed a hybrid technology to produce jet fuel from a feedstock blend of coal and biomass. Collaborating with Altex, Argonne National Laboratory has expanded and used the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model to assess the life-cycle GHG emissions and water consumption of this hybrid technology. Biomass feedstocks include corn stover, switchgrass, and wheat straw. The option of biomass densification (bales to pellets) is also evaluated in this study. The results show that the densification process generates additional GHG emissions as a result of additional biomass process energy demand. This process coproduces a large amount of char, and this study investigates two scenarios to treat char: landfill disposal (Char-LF) and combustion for combined heat and power (CHP). Since the CHP scenarios export excess heat and electricity as coproducts, two coproduct handling methods are used for well-to-wake (WTWa) analysis: displacement (Char-CHP-Disp) and energy allocation (Char-CHP-EnAllo). When the feedstock contains 15 wt% densified wheat straw and 85 wt% lignite coal, WTWa GHG emissions of the coal-and-biomass-to-liquid pathways are 116, 97, and 137 gCO2e per megajoule (MJ) under the Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo scenarios, respectively, as compared to conventional jet fuel production at 84 gCO2e/MJ. WTWa water consumption values are 0.072, -0.046, and 0.044 gal/MJ for Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo, respectively, as compared to conventional jet fuel production at 0.028 gal/MJ. To reach the break-even point of 84 gCO2e/MJ, under the assumptions of constant product yields and energy demands regardless of the share of biomass and coal feedstocks, 31 wt%, 23 wt%, and 53 wt% of the feedstock blend need to be biomass under the Char-LF, Char-CHP-Disp, and Char-CHP-EnAllo scenarios, respectively.},
doi = {10.2172/1372111},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

Technical Report:

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