Advanced two-phase digestion of sewage sludge

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6935462

Ghosh, S

This paper describes the development and operating results of a novel configuration of the two-phase digestion concept. The two-phase system, comprises two custom-designed upflow digesters, which were operated in tandem to optimize the liquefying-acidification and acetogenesis-methanation reactions. The results are based on system operation for more than one year with a high-metal-content sewage sludge. During the operating period, the system exhibited an increasing methane yield at hydraulic retention times (HRT) of less than 6 days. With continuing culture enrichment and improvements in reactor design, the methane yield increased from 5 to 6.8 SCF/lb VS added, and then to 7.7 SCF/lb VS added. This methane yield was about 80% of the theoretical methane yield achievable with this sewage sludge--and the highest methane yield reported for sludge at this HRT. Operation of the novel process configuration was very stable and superior to that of conventional single-stage digestion in terms of methane yield, gas generation rate, and net energy production. About 75 weight percent of the organic solids was gasified; this could be the maximum attainable feed conversion efficiency for sludge, considering that between 75% and 80% of this feed is normally biodegradable. 3 references, 7 tables.

• Research Organization: Institute of Gas Technology, Chicago, IL (USA)
• OSTI ID: 6935462
• Report Number(s): CONF-840111-11; ON: TI84901430
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090122* -- Hydrocarbon Fuels-- Preparation from Wastes or Biomass-- (1976-1989)
ALKANES
ANAEROBIC DIGESTION
BIOCONVERSION
BIOREACTORS
DATA
DIAGRAMS
DIGESTION
EXPERIMENTAL DATA
FLOWSHEETS
GAS YIELDS
HYDROCARBONS
INFORMATION
MANAGEMENT
METHANE
NUMERICAL DATA
ORGANIC COMPOUNDS
PROCESSING
PRODUCTION
SEWAGE
SEWAGE SLUDGE
SLUDGES
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
YIELDS