Pretreatment of piggery wastewater by a stable constructed microbial consortium for improving the methane production

Jian Cai, Xiwei Mo, Guojun Cheng, Dongyun Du
2015 Water Science and Technology  
A stable aerobic microbial consortium, established by successive subcultivation, was employed to solubilize the solid organic fraction in swine wastewater. In the 30 days' successive biological pretreatments, 30-38% of volatile solids and 19-28% total solids in raw slurry were solubilized after 10 hours at 37 W C. Meanwhile, soluble chemical oxygen demand (COD) and volatile fatty acid increased by 48%-56% and 600%-750%, respectively. Furthermore, the molecular microbial profile of the
more » ... in successive pretreatment was conducted by denaturing gradient gel electrophoresis (DGGE). The results indicated that bacterial species of the consortium rapidly overgrew the indigenous microbial community of raw water, and showed a stable predominance at the long-term treatment. As a consequence of biological pretreatment, pretreatment shortened digestion time by 50% and increased biogas production by 45% compared to raw water in the anaerobic process. The microbial consortium constructed herein is a potential candidate consortium for biological pretreatment of swine wastewater to enhance biogas production.
doi:10.2166/wst.2015.017 pmid:25768225 fatcat:4appccfoq5b45ggqbgxxs75edm