1) For the old biogas tanks built by farmers, the volume is too small, and the sewage retention time in the tank is too short, resulting in too high sewage concentration. In this case, the livestock and poultry manure solid-liquid separator should be used before the sewage enters the tank. It can effectively reduce the COD and BOD content of the sewage and reduce the operating load of the biogas tank, thereby simplifying the sewage discharge;
2) The use of a solid-liquid separator can transform the feces in the fresh sewage into valuable fish feed or organic fertilizer. The separated sewage intermittently enters the biogas tank, which allows the anaerobic tank to have a sufficient digestion time. The active bacteria in the tank reproduce more vigorously and produce more gas. The content of gas methane is naturally high, and the high purity of the gas naturally overcomes the problem of abnormal operation of the biogas generator;
3) The sewage treated by the solid-liquid separator enters the biogas tank. It can effectively solve the problem of crusting in biogas digesters and eliminate the need to clean up biogas residues;
4) The use of livestock and poultry manure solid-liquid separators can reduce the investment in the construction of biogas digesters. For example, if a breeding or slaughterhouse that discharges 100 tons of sewage every day uses a matching livestock and poultry manure solid-liquid separator for early treatment, the investment in the construction of anaerobic digesters can be reduced by 300 cubic meters, because the concentration of feces and sewage mixed into the digester is too high. The anaerobic time also needs to be extended accordingly.
Therefore, for a breeding farm that discharges 100 tons of sewage every day, if the livestock and poultry manure solid-liquid separator is not used for treatment, then the investment in the construction of anaerobic digesters will be 1000-1200 cubic meters. If a livestock and poultry manure solid-liquid separator is used, the construction can be reduced by 300-400 cubic meters.
