Effect of recycling thermophilic sludge on the activated-sludge process. Report for October 1984-June 1989

Technical Report · Mon Jan 01 00:00:00 EST 1990

OSTI ID:6556745

Prakasam, T B.S.; Soszynski, S; Zenz, D R; Lue-Hing, C; Blyth, L

A full-scale investigation was undertaken at Chicago's Hanover Park Water Reclamation Plant (WRP) to study whether the net sludge production from the WRP could be reduced by implementing a scheme developed by W. Torpey et al. (1984). In this process, sludge is withdrawn from a thermophilic digester operated in series with a mesophilic digester and partially recycled into the aeration tanks of the activated sludge system. The Hanover Park WRP, which has a design flow capacity of 45,420 million cu m per day (12 mgd), was split into a control section and an experimental section. The two sections were operated similarly except the thermophilic drawoff was recycled into the aeration tanks of the experimental section from a digester system consisting of mesophilic and thermophilic digesters operated in series. A reduction in net sludge production of about 10 percent was achieved at 40 percent recycle of thermophilic sludge into the aeration tanks at the Hanover Park WRP. This was a much smaller reduction than obtained by Torpey et al. Sludge dewatering properties were not improved. The recycling produced no adverse effects on quality of the treated wastewater.

• Research Organization: Metropolitan Water Reclamation District of Greater Chicago, IL (USA)
• OSTI ID: 6556745
• Report Number(s): PB-90-258518/XAB; CNN: EPA-R-811925
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
54 ENVIRONMENTAL SCIENCES
SEWAGE SLUDGE
RECYCLING
ACTIVATED SLUDGE PROCESS
AERATION
BIOTECHNOLOGY
OXIDATION
PERFORMANCE TESTING
PROGRESS REPORT
WASTE WATER
WATER RECLAMATION
CHEMICAL REACTIONS
DOCUMENT TYPES
HYDROGEN COMPOUNDS
LIQUID WASTES
MANAGEMENT
OXYGEN COMPOUNDS
PROCESSING
SEWAGE
SLUDGES
TESTING
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
WATER
320305* - Energy Conservation
Consumption
& Utilization- Industrial & Agricultural Processes- Industrial Waste Management
540320 - Environment
Aquatic- Chemicals Monitoring & Transport- (1990-)