The efficiencies of small scale biogas digesters in pig manure treatment in the Mekong delta

Abstract

Biogas digester for treatment of pig manure was rapidly gaining interest in both farmers and scientists in the Mekong delta. The largest advantage of anaerobic digestion is energy recovery. Biogas collected from biogas digester is used as a substitute for fossil fuels to produce heat; whereas digestion can be used as a fertilizer or soil conditioner. Due to animal husbandry and biogas digester development, abundant effluence produced courses environmental problems. There are increasing concerns about manure treatment ability of the biogas digesters. However, many different models of biogas digester are available on the market and therefore it is unknown which one can treat pig manure efficiency. The study was conducted in four different models of biogas digester: polyethylene (PE), high density polyethylene (HDPE), fixed dome and composite models. In average, the reduction of TSS, BOD5, COD and oDM of HDPE system were 73%, 63%, 79% and 61% respectively. The results also showed that fixed dome model was the most efficient in pig manure treatment compared to other models.