Passive solar technology aids biogas digesters

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · BioCycle; (USA)

OSTI ID:5795602

Farming communities throughout China rely on biogas generators as a primary source of light and heat, as well as using the sludge as a nitrogen-rich fertilizer. Now researchers at Beijing's Solar Energy Laboratory have improved efficiency by building a rectangular tank out of concrete slabs, with one slanted surface painted black and covered with glass. According to a report in New Scientist, this passive solar panel generates heat in the same way as a greenhouse, raising inside temperatures by 10{degree}C and increasing biogas production by 50%. Another advantage of the new tanks is easy access, since the tank's lid sites in wells of water which form a seal against oxygen. (Old biogas tanks were made of soil, sand and a little concrete, prone to developing severe cracks which would allow oxygen to enter thus slowing down anaerobic reaction). Explains Debora MacKenzie of New Scientist: with the new tank, the farmer can simply remove the lid and attack the contents with a spade. This means that the mixture can comprise more than 10% solids. Greater density allows smaller tanks. Rural families need one cubic meter of biogas daily for light and heat; instead of the former 8 cm biogas generator, the new tanks need only be 1 cm. The prediction is that the smaller size could make biogas more popular in China's crowded towns. The biogas department is headed by He Shao Qi, who is also investigating ways to reduce production costs for the tanks.

• OSTI ID: 5795602
• Journal Information: BioCycle; (USA), Vol. 29:6; ISSN 0276-5055
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
BIOGAS PROCESS
TECHNOLOGY UTILIZATION
BIODEGRADATION
CHINA
COST
SLUDGES
SOLAR EQUIPMENT
ANAEROBIC DIGESTION
ASIA
BIOCONVERSION
CHEMICAL REACTIONS
DECOMPOSITION
DIGESTION
EQUIPMENT
MANAGEMENT
PROCESSING
WASTE MANAGEMENT
WASTE PROCESSING
090900* - Biomass Fuels- Processing- (1990-)
093000 - Biomass Fuels- Economic
Industrial
& Business Aspects- (1990-)