Bench-Scale Evaluation of Hydrothermal Processing Technology for Conversion of Wastewater Solids to Fuels

Journal Article · Sun Apr 01 04:00:00 EDT 2018 · Water Environment Research

OSTI ID:1434855

Marrone, Philip A.; Elliott, Douglas C.; Billing, Justin M.; Hallen, Richard T.; Hart, Todd R.; Kadota, Paul; Moeller, Jeff C.; Randel, Margaaret A.; Schmidt, Andrew J.

Hydrothermal Liquefaction (HTL) and Catalytic Hydrothermal Gasification (CHG) proof-of-concept bench-scale tests were performed to assess the potential of hydrothermal treatment for handling municipal wastewater sludge. HTL tests were conducted at 300-350°C and 20 MPa on three different feeds: primary sludge, secondary sludge, and digested solids. Corresponding CHG tests were conducted at 350°C and 20 MPa on the HTL aqueous phase output using a ruthenium based catalyst. Biocrude yields ranged from 25-37%. Biocrude composition and quality were comparable to biocrudes generated from algae feeds. Subsequent hydrotreating of biocrude resulted in a product with comparable physical and chemical properties to crude oil. CHG product gas methane yields on a carbon basis ranged from 47-64%. Siloxane concentrations in the CHG product gas were below engine limits. The HTL-CHG process resulted in a chemical oxygen demand (COD) reduction of > 99.9% and a reduction in residual solids for disposal of 94-99%.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1434855
• Report Number(s): PNNL-SA-131515; BM0102060
• Journal Information: Water Environment Research, Journal Name: Water Environment Research Journal Issue: 4 Vol. 90; ISSN WAERED; ISSN 1061-4303
• Country of Publication: United States
• Language: English

Related Subjects

biocrude
catalyst
gasification
hydrothermal
hydrotreating
liquefaction
sludge
upgrading
wastewater solids