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Title: Energy conservation and production in a packed-bed anaerobic bioreactor

Oak Ridge National Laboratory (ORNL) is developing an energy-conserving/ producing wastewater treatment system based on a fixed-film anaerobic bioreactor. The treatment process is based on passing wastewaters upward through the bioreactor for continuous treatment by gravitational settling, biophysical filtration and biological decomposition. A two-year pilot-plant project using a bioreactor designed to treat 5000 gpd has been conducted using raw wastewater on a municipal site in Oak Ridge, Tennessee. Data obtained for the performance of the bioreactor during this project have been analyzed by ORNL and Associated Water and Air Resources Engineers (AWARE), Inc. of Nashville, Tennessee. From these analyses it was estimated that hydraulic loading rates of 0.25 gpm/ft/sup 2/ and hydraulic residence times of 10 hours could be used in designing such bioreactors for the secondary treatment of municipal wastewaters. Conceptual designs for total treatment systems processing up to one million gallons of wastewater per day were developed based on the performance of the pilot plant bioreactor. These systems were compared to activated sludge treatment systems also operating under secondary treatment requirements and were found to consume as little as 30% of the energy required by the activated sludge systems. Economic advantages of the process result from the eliminationmore » of operating energy requirements associated with the aeration of aerobic-based processes and with the significant decrease of sludge-handling costs required with conventional activated sludge treatment systems.Furthermore, methane produced by anaerobic fermentation processes occurring during the biological decomposition of carbonaceous wastes also represented a significant and recoverable energy production. For dilute municipal wastewaters this would completely offset the remaining energy required for treatment, while for concentrated industrial wastewater would result in a net production of energy.« less
Authors:
;
Publication Date:
OSTI Identifier:
5719328
Report Number(s):
CONF-800129-4
DOE Contract Number:
W-7405-ENG-26
Resource Type:
Conference
Resource Relation:
Conference: Energy from biomass and wastes 4 symposium, Lake Buena Vista, FL, USA, 21 Jan 1980
Research Org:
Oak Ridge National Lab., TN (USA)
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; METHANE; BIOSYNTHESIS; MUNICIPAL WASTES; ANAEROBIC DIGESTION; CHEMICAL REACTORS; COST; FINANCIAL DATA; FLOWSHEETS; OAK RIDGE; PILOT PLANTS; TABLES; WASTE MANAGEMENT; WASTE PROCESSING; ALKANES; BIOCONVERSION; CRYOGENIC FLUIDS; DATA; DATA FORMS; DIAGRAMS; DIGESTION; FLUIDS; FUNCTIONAL MODELS; HYDROCARBONS; INFORMATION; MANAGEMENT; NORTH AMERICA; ORGANIC COMPOUNDS; PROCESSING; SOUTHEAST REGION; SYNTHESIS; TENNESSEE; USA; WASTES 090122* -- Hydrocarbon Fuels-- Preparation from Wastes or Biomass-- (1976-1989); 320604 -- Energy Conservation, Consumption, & Utilization-- Municipalities & Community Systems-- Municipal Waste Management-- (1980-); 140504 -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)