Effects of temperature on methanogenesis in a thermophilic (58 degrees C) anaerobic digester

Journal Article · Sun Apr 01 04:00:00 EST 1984 · Appl. Environ. Microbiol.; (United States)

OSTI ID:6630986

Zinder, S H; Anguish, T; Cardwell, S C

The short-term effects of temperature on methanogenesis from acetate or CO2 in a thermophilic (58 degrees C) anaerobic digestor were studied by incubating digestor sludge at different temperatures with 14C-labeled methane precursors (14CH3COO- or 14CO2). During a period when Methanosarcina sp. was numerous, methanogenesis from acetate was optimal at 55 to 60 degrees C and was inhibited at 65 degrees C. A Methanosarcina culture isolated from the digestor grew optimally on acetate at 55 to 58 degrees C and did not grow or produce methane at 65 degrees C. A shift of digestor temperature from 58 to 64 degrees C caused a sharp decrease in gas production and a large increase in acetate concentration indicating that the aceticlastic methanogens were the population most susceptible to this temperature increase. During a later period when Methanothrix sp. was numerous, methanogenesis from 14CH3COO- was optimal at 65 degrees C and inhibited at 75 degrees C. A partially purified Methanothrix enrichment culture derived from the digestor had a maximum growth temperature near 70 degrees C. Methanogenesis from 14CO2 was optimal at 65 degrees C and still proceeded at 75 degrees C. A CO2-reducing Methanobacterium sp. isolated from the digestor was capable of methanogenesis at 75 degrees C. During the period when Methanothrix sp. was dominant, sludge incubated for 24 h at 65 degrees C produced more methane than sludge incubated at 60 degrees C, and no acetate accumulated at 65 degrees C. Methanogenesis was severely inhibited at 70 degrees C, but since neither acetate nor H2 accumulated, production of these methanogenic substrates by fermentative bacteria was probably the most temperature-sensitive process. Thus, there was a correlation between digestor performance at different temperatures and responses to temperature by cultures of methanogens believed to play important roles in the digestor. (Refs. 19).

• Research Organization: Dept of Microbiology, Cornell Univ, Ithaca, NY 14853
• OSTI ID: 6630986
• Journal Information: Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 47:4; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090122* -- Hydrocarbon Fuels-- Preparation from Wastes or Biomass-- (1976-1989)
ACETATES
ALKANES
ANAEROBIC DIGESTION
BACTERIA
BIOCONVERSION
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACID SALTS
CHALCOGENIDES
CHEMICAL REACTIONS
DIGESTION
HYDROCARBONS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MANAGEMENT
MEDIUM TEMPERATURE
METHANE
METHANOGENIC BACTERIA
MICROORGANISMS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PROCESSING
PRODUCTION
REDUCTION
TEMPERATURE EFFECTS
THERMOPHILIC CONDITIONS
TRACER TECHNIQUES
WASTE MANAGEMENT
WASTE PROCESSING