NOVELTY - Composite up-flow sludge anaerobic digester comprises a reaction zone, a storage zone, a precipitation zone and a gas-liquid separating zone. The composite up-flow sludge anaerobic digester comprises a digester main body, an inlet mud pipe, an outlet mud pipe and a marsh gas pipe set at the top part of the digester main body. The digester main body is provided with a lower reaction zone. A feeding bar is set on the upper part of the reaction zone. The bottom of the reaction zone is set with a biogas aerator, and is connected with a marsh gas pump. The digester further comprises a mud exhaust.    USE - Used as a composite up-flow sludge anaerobic digester.    ADVANTAGE - The composite up-flow sludge anaerobic digester improves the reaction rate of the reaction zone, and reduces environmental pollution.    DETAILED DESCRIPTION - Composite up-flow sludge anaerobic digester comprises a reaction zone, a storage zone, a precipitation zone and a gas-liquid separating zone. The composite up-flow sludge anaerobic digester comprises a digester main body, an inlet mud pipe, an outlet mud pipe and a marsh gas pipe set at the top part of the digester main body. The digester main body is provided with a lower reaction zone. A feeding bar is set on the upper part of the reaction zone. The bottom of the reaction zone is set with a biogas aerator, and is connected with a marsh gas pump. The gas-liquid separating zone is provided with the upper part of the digester main body. The reaction zone through a flow tube and a flow section is connected with a reducing pipe at the bottom of the lower part of the reaction zone. The digester further comprises a mud exhaust connected with a pulse electrophoretic separating zone in an electrophoresis zone, which is provided with an insoluble electrophoretic anode. The inlet mud pipe comprises a bacterial filter and elastic stereo honeycomb biological filler.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the composite up-flow sludge anaerobic digester.