NOVELTY - Electric fertilizer and biogas are co-produced by mixing the pretreated fluidized raw material, low-solid content raw material, high-solid content raw material and biogas solution; inoculating the mixed raw materials; performing anaerobic dry fermentation to the inoculated mixed raw materials; separating solid from liquid to obtain solid biogas slag and liquid biogas; sterilizing the biogas slag at high temperature to obtain solid organic fertilizer; and purifying liquid biogas to produce heat while producing electricity and vapor.    USE - Method of co-production of electric fertilizer and biogas (claimed).    ADVANTAGE - The method improves waste disposing capability and biogas production capability, and guarantees continuous circulation of the anaerobic dry fermentation while simultaneously producing electric energy and high-quality solid organic fertilizer.    DETAILED DESCRIPTION - Co-production of electric fertilizer and biogas comprises:    (A) removing inorganic impurity in fluidized raw material, crushing low-solid content raw material to reduce particle diameter to below 20 mm, and crushing high-solid content raw material to reduce the particle diameter to below 40 mm;    (B) mixing the pretreated fluidized raw material, low-solid content raw material, high-solid content raw material and biogas solution, controlling total solid (TS) concentration of mixed raw materials to 15-40%, and controlling feed ratio of high-carbon raw material, high-nitrogen raw material and carbon-nitrogen raw material, in which carbon/nitrogen ratio of mixed raw material is 15-30:1 and the mixed raw materials comprise easily hydrolyzable acidified raw material and the difficult to hydrolyze acidified raw material;    (C) inoculating the mixed raw materials using fermentation residue in a dry fermentation reactor as inoculated substance, where the inoculating size is 15-80% of the total mass of the mixed raw material, agitating and mixing the inoculated substances;    (D) performing anaerobic dry fermentation by fermenting the inoculated mixed raw material in sealed dry fermentation reactor to produce biogas, feeding and discharging for 1-2 times every day, where each feeding amount is the same as the discharging amount, firstly discharging before feeding, controlling the fermentation temperature to 30-60 degrees C, where the retention time of the material in the dry fermentation reactor is 15-30 days;    (E) separating solid from liquid by using a part of unloaded fermentation residue as inoculated substance, subjecting the remaining part to solid-liquid separation, controlling water content of solid biogas slag after separating solid from liquid to 20-35%, and storing the liquid part of the biogas solution after separating solid from liquid in the biogas storage tank for later use and for adjusting the TS concentration of the raw material feed;    (F) sterilizing the biogas slag obtained by separating solid from liquid at high temperature, and using the sterilized biogas slag as solid organic fertilizer; and    (G) after purifying the liquid biogas produced by anaerobic fermentation, producing remaining heat by power generating system while producing electricity, producing vapor by the remaining heat recycling device, using vapor for high-temperature sterilization of the biogas slag, changing the vapor to complete sterilization into high-temperature hot water, using high-temperature hot water for dry fermentation reactor to heat and insulate temperature, and then changing into low-temperature cold water, and sending low-temperature cold water into the remaining heat recycling device for circularly producing vapor.