Maximizing net energy production in municipal wastewater treatment

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1982

OSTI ID:5397528

Wetzel, E D

A steady state mathematical model was developed to analyze the energy requirements and production for a municipal wastewater treatment facility. The modeled processes included primary treatment, secondary treatment with conventional activated sludge or plastic media trickling filtration, gravity or dissolved air flotation thickening and anaerobic digestion. The energy content of the methane generated by the digester was compared with the energy required by individual unit processes and general facility pumping demands. The sensitivity of the process variables was determined by varying input data values from a baseline condition and comparing net energy production. The verified model was used to determine the combination of processes and operating conditions that result in the maximum net energy production for the facility. Secondary sludge thickening was shown to be an essential element for energy-efficient design. Plastic media trickling filters generally resulted in higher net energy production than the activated sludge process, with filter effluent recycle preferred over clarifier supernatant recycle. The benefits of operating the digester at low temperature (20/sup 0/C) and in the anaerobic contact mode were demonstrated. The energy recovered from the digester gas must exceed 50% for energy self-sufficiency to be feasible.

• Research Organization: Lehigh Univ., Bethlehem, PA (USA)
• OSTI ID: 5397528
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320604 -- Energy Conservation
Consumption
& Utilization-- Municipalities & Community Systems-- Municipal Waste Management-- (1980-)
42 ENGINEERING
420900* -- Engineering-- Waste Processing Plants & Equipment-- (-1989)
ACTIVATED SLUDGE PROCESS
ALKANES
ANAEROBIC DIGESTION
BIOCONVERSION
CONVERSION
DIGESTION
EFFICIENCY
ENERGY
ENERGY ANALYSIS
ENERGY CONVERSION
ENERGY EFFICIENCY
ENERGY RECOVERY
HYDROCARBONS
HYDROGEN COMPOUNDS
INDUSTRIAL PLANTS
LIQUID WASTES
MANAGEMENT
MATHEMATICAL MODELS
METHANE
MUNICIPAL WASTES
NET ENERGY
OPTIMIZATION
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PROCESSING
RECOVERY
WASTE MANAGEMENT
WASTE PROCESSING
WASTE PROCESSING PLANTS
WASTE WATER
WASTES
WATER