TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: A deepened anaerobic step for conveying the methane solution to the deepened anaerobic tank for anaerobic reaction, where the methane gas outlet is arranged on the top of the deepened anaerobic tank, the methane gas outlet is connected to the methane gas collecting tank by the pipeline, a sludge outlet of the sludge sedimentation tank is arranged on the bottom of the deepened anaerobic tank, a supernatant outlet is arranged on the upper part of the deepened anaerobic tank, which is connected with a methane gas release tank or a continuous acidified anaerobic tank by the pipeline, the supernatant passing through the methane gas release tank is sent for refilling liquid, and the gas outlet of the methane gas release tank is connected to the methane gas collecting tank by the pipeline. Preferred Method: The sludge sedimentation concentration step for placing the sludge transferred in the sludge sedimentation tank for sedimenting, and conveying the supernatant in the sludge sedimentation tank to the buffering adjusting tank, after taking out the sedimented sludge, drying it and making into fertilizer or fire coal, where the step is performed in the sealed space, the methane gas outlet is arranged in the sealed space, and the methane gas outlet is connected to the methane gas collecting tank by the pipeline. The method comprises adding at least one assistant crushing step and one assistant elutriation flotation step after the primary crushing step and the primary elutriation flotation step. The assistant crushing step comprises crushing the conveyed waste with lighter specific weight, striking the residual partial organic waste into pulp, making the volume of solid waste smaller, and separating the inorganic waste from the organic garbage, then separating the organic waste from the inorganic waste, where the size of the solid waste assures to be conveyed by the sediment conveying device in the assistant elutriation flotation step, and the sizes of plastic and textile waste assures the screening and separation in the subsequent procedure. The assistant elutriation flotation step comprises placing the waste in the assistant elutriation flotation tank, performing aeration elutriation, transferring the waste with greater specific weight on the bottom of the elutriation flotation tank in the sediment cleaning device by the sediment conveying device, recycling after cleaning, transferring the waste with lighter specific weight in the elutriation flotation tank to the next step by the floater conveying device, and conveying the assistant elutriation flotation solution containing pulp-shaped organic waste to the acidified anaerobic kettle by the pipeline. The sediment conveying device is a spiral conveyor, and the floater conveying device is a spiral conveyer. The sediment cleaning device is a sand washer, and the washing solution of sand washer is conveyed to the acidified anaerobic pond by the pipeline. The cleaned sediment is conveyed to a building material workshop for making building materials. The assistant magnetic separation step is added after the primary crushing step, and the step is used for performing magnetic separation to the waste processed in the primary crushing step again, and separating the residual waste iron in the waste and recycling. The assistant magnetic separation step is added before the acidified anaerobic step, and the step is used for performing magnetic separation to the waste entering the acidified anaerobic tank again, and separating the residual waste iron in the waste and recycling. The complete processing steps and devices relating to the processing steps are performed in a closed workshop. The gas producing unit and the methane collecting tank is located outside the closed workshop. The closed workshop is provided with multiple negative pressure mixed air collecting ports connected to the air inlet of the gas producing unit by the pipeline. The negative pressure mixed air collecting ports are arranged at the odor diffusion place in the workshop and/or the odor escape place for diffusing odor outside the workshop. A mixed gas collecting cap for methane gas and mixed air is arranged at the screening device in the screening separation step, and the mixed air outlet of the mixed gas collecting cap is connected to the air inlet of the gas producing unit by the pipeline. A methane solution heating device is also arranged in the buffering adjusting tank in the buffering adjusting step to accelerate the speed of anaerobic reaction. The heat medium of the methane solution heating device is from the cooling water of the gas producing unit and/or the tail gas of the gas producing unit. The uniform cutting step is cutting the waste by a pressing method. The first solid/liquid discharge port and the second solid/liquid discharge port in the acidified anaerobic step are opened alternately. The methane gas release tank in the deepened anaerobic step releases methane gas in supernatant by spraying. The plastics and chemical fibers screened in the screening separation step are cracked to prepare fuel oil. The external refilled water for recycling and utilizing household waste is originated from urban and rural sewage or sewage containing high chemical oxygen demand.