Municipal wastewater sludge as a renewable, cost-effective feedstock for transportation biofuels using hydrothermal liquefaction

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:270

Article

Seiple, Timothy E.¹  Skaggs, Richard L.¹  Fillmore, Lauren²  Coleman, Andre M.¹ 

[1] Pacific Northwest Natl Lab, POB 999,K9-33, Richland, WA 99354 USA

[2] Water Res Fdn, 1199 N Fairfax St,Suite 900, Alexandria, VA 22314 USA

关键词: Waste to energy;    Energy recovery;    Wastewater;    Sewage sludge;    Biosolids;    Biofuels;   

DOI  :  10.1016/j.jenvman.2020.110852

来源: Elsevier

【 摘 要 】

U.S. municipal wastewater contains approximately 160 trillion Btu/y of influent chemical energy, but very little is recovered and utilized nationwide. Hydrothermal liquefaction (HTL) is a thermochemical process that converts biomass into a biocrude intermediate that can be upgraded to a variety of liquid fuels. HTL provides an opportunity to enhance energy recovery at wastewater treatment plants by transforming underutilized municipal wastewater solids into a renewable, cost-effective feedstock for transportation biofuels. In this study, we estimate total national economic sludge feedstock supply by performing discounted cash flow analyses at >15,000 U.S. wastewater treatment facilities to assess the net present value of 30-year HTL investments, with comparison to wider adoption of anaerobic digestion (AD). This analysis is the first to model HTL technology deployment across the real-world fleet of wastewater treatment plants. Analyses indicate treatment facilities >17 ML/d (4.6 million gal/d) could supply 9.77 Tg/y of dry solids feedstock to economically produce 3.67 GL/y of biocrude intermediate, thereby increasing energy, environmental, and financial sustainability of sludge treatment while reducing disposal costs and operational and environmental risk.

【 授权许可】

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