Interrelationships among anaerobic digestion, sludge dewaterability, and particle characteristics

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5711561

Chung, Y J

The main objective of this study was to define the interrelationships among anaerobic digestion, sludge dewaterability, and particle characteristics. For this purpose, laboratory scale high-rate anaerobic digesters were designed and operated under various conditions. The reactors were operated under varying conditions of feed strength, feed composition (mixtures of primary and secondary sludge), detention time, and temperature. In each experimental set, one variable was fixed at several different levels while others were held at a single standard value. Digestion performance was monitored by frequent measures of influent and effluent total solids, volatile solids, COD, alkalinity, and volatile acids, and measurements of gas production and composition. Particle characteristics measured were of size distribution, density, and surface charge. Dewaterability was measured as specific resistance and Capillary Suction Time. Digestion generally improved dewaterability, but often in complicated ways. For example, the specific resistance was reduced 65% with a 7-day detention time, but increased detention time lessened the improvement. A small fraction of activated sludge (20% by weight of solids) in the digester influent led to a greater improvement (81% reduction) in dewaterability than no activated sludge (20% reduction), but digestion of 100% activated sludge led to worse dewaterability. Other variables had lesser effects on dewaterability. The particle size distribution results, when analyzed for the surface area of particles, explained these results well.

• Research Organization: Texas Univ., Austin (USA)
• OSTI ID: 5711561
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090222* -- Alcohol Fuels-- Preparation from Wastes or Biomass-- (1976-1989)
ANAEROBIC DIGESTION
BENCH-SCALE EXPERIMENTS
BIOCONVERSION
BIOREACTORS
CHEMICAL FEEDSTOCKS
DESIGN
DIGESTION
MANAGEMENT
OPERATION
PARTICLE SIZE
PROCESSING
SEWAGE
SEWAGE SLUDGE
SIZE
SLUDGES
SURFACE AREA
SURFACE PROPERTIES
WASTE MANAGEMENT
WASTE PROCESSING
WASTES