Effects of newly anaerobic fermentation system on reducing fecal coliforms and total suspended solids content in sewage of large-scaled pig farms

In order to evaluate the operation of anaerobic fermentation system，ten large-scaled pig farms were selected in Guangdong province to monitor the fecal coliforms（FCB）and total suspended solids（TSS）content in sewage discharged from the hoggery and methane tank. The results showed that the values of 102 802×104-490 589 ×104 individuals/L and 1 181-4 680 mg/L were recorded for FCB and TSS，respectively. The anaerobic fermentation system displayed an effective performance in reducing the two pollutants of hoggery sewage，and the reduction rates were 77.74%-99.24% and 18.74%-90.36%，respectively. FCB content and TSS content in methane tank were 2 589 ×104-49 555×104 individuals/L and 13-8 057 mg/L，which were further treated by fish ponds and oxidation pond. FCB content in the sewage discharged from the pig farm all exceeded the value of the discharge standard of pollutants for livestock and poultry breeding. The results indicate that the FCB and TSS in sewage discharged from pig farm possess the pollution potential to surrounding environment.