Energy recovery from biosolids: The City of Los Angeles experience

Conference · Wed Nov 01 04:00:00 EST 1995

OSTI ID:115296

Haug, R T; Moore, G L ^[1]; Harrison, D S ^[2]

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1. Bureau of Engineering, Los Angeles, CA (United States)
2. Montgomery Watson Americas, Inc., Pasadena, CA (United States)

The City of Los Angeles` Hyperion Treatment Plant serves an area of 1,500 sq km (600 sq mi) with a contributory population of nearly 4 million. The plant currently produces more than 250 dry tonnes per day (dtpd) of digested, dewatered biosolids and is being expanded and upgraded to provide pure oxygen, full secondary treatment by 1998. The modern Hyperion Plant began operating in 1951. Since that time, Hyperion has provided anaerobic digestion for its biosolids and has used the produced biogas for power generation. In the 1980`s the City completed a major expansion of its power generation and biosolids handling facilities at Hyperion. These facilities became known as the Hyperion Energy Recovery System (HERS) and their objective is to maximize the recovery of energy from the renewable biosolids. Today, these facilities are operational and continue to be modified to optimize performance and expanded to meet the increased loadings from full secondary treatment. Biogas produced by the anaerobic digestion process is compressed, scrubbed to remove H{sub 2}S, and used to power a gas turbine, combined cycle cogeneration system. Emergency flares are provided in the event of a power plant outage. A portion of the biosolids are transported offsite for beneficial reuse, such as composting and direct land application. The remaining solids are centrifugally dewatered and dried by indirect rotary dryers to produce about 50 dtpd of dried biofuel. Biofuel produced from the drying processes is fired in a fluidized bed gasification and staged combustion process (FBC) designed to recover energy and reduce air emissions. Superheated steam is produced in a waste heat boiler and converted to electrical power is a condensing steam turbine. Bioash from the FBC`s is contracted for off-site reuse, primarily as a fluxing agent in copper smelting and as a source of silica, aluminum, iron and calcium for manufacture of portland cement.

• Research Organization: National Renewable Energy Lab., Golden, CO (United States)
• OSTI ID: 115296
• Report Number(s): NREL/CP--200-8098; CONF-9508104--; ON: DE95009230
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
ANAEROBIC DIGESTION
ENERGY RECOVERY
LOS ANGELES
METHANE
MUNICIPAL WASTES
PORTLAND CEMENT
POWER GENERATION
REFUSE-FUELED POWER PLANTS
WASTE MANAGEMENT
WASTE PROCESSING
WASTE PRODUCT UTILIZATION