NOVELTY - Recycling and utilizing household waste in city and town comprising an acidified anaerobic tank, a deepened anaerobic tank, a methane gas collecting tank, and a gas producing unit, comprises waste receiving step for discharging transported waste in a waste hopper or waste bin, an uniform distributing step for transferring uniformly the waste, a primary magnetic separation step, a primary crushing step, a primary elutriation flotation step, uniform cutting step, an acidified anaerobic step, a buffering adjusting step, a deepened anaerobic step, and a sludge sedimentation concentration step.    USE - The method is useful for recycling and utilizing household waste.    ADVANTAGE - The method overcomes the maximum constriction for restraining waste treatment; can make the anaerobic method process waste continuously; and can completely recycle the resources including aerobic waste e.g. waste plastics and waste fibers.    DETAILED DESCRIPTION - Recycling and utilizing household waste in city and town comprising an acidified anaerobic tank, a deepened anaerobic tank, a methane gas collecting tank and a gas producing unit, where the gas inlet of the gas producing unit is connected to the methane gas collecting tank by a pipeline, comprises a waste receiving step for discharging the transported waste in a waste hopper or a waste bin, an uniform distributing step for transferring uniformly the waste in the waste hopper or the waste bin, assuring the continuous operation, and preventing the stoppage or interruption, in the step, tearing the waste bag in the waste hopper or the waste bin, tearing and cutting off large plastic waste, wood waste, and textile waste, separating the inorganic waste and organic waste, then transferring uniformly the torn and cut waste into the next step, where the volume of processed solid waste in the step satisfies the crushing demand of crushing machine in the primary crushing step; a primary magnetic separation step for magnetically separating the waste transferred, separating the waste iron from the waste, preventing the waste iron from damaging the crushing machine in the primary crushing step, and recycling the waste iron in the waste; a primary crushing step for further crushing the waste transferred in the previous step, cutting off the plastic and textile waste, separating the waste iron covered by solid waste, striking the partial organic waste into pulp shape, making the volume of solid waste smaller, where the size of the solid waste assures to be conveyed by a sediment conveying device in the primary elutriation flotation step, and the sizes of the plastic and textile waste assure selection and separation; a primary elutriation flotation step for placing the waste processed in the above steps in a primary elutriation flotation tank and performing aeration elutriation, transferring the solid waste with greater specific weight on the bottom of the primary elutriation flotation tank in a sediment cleaning device by the sediment conveying device, recycling after cleaning, transferring the waste with lighter specific weight to the next step by a floater conveying device, and transferring the primary elutriation flotation solution containing pulp-shaped organic waste to the acidified anaerobic tank by pipeline; an uniform cutting step for further cutting the waste with lighter specific weight transferred from the step above, in which thoroughly cutting off the long strip of waste, or separating out the long strip of waste from the waste with lighter specific weight and further cutting, thoroughly cutting off the long strip of waste, preventing the stoppage of the pipeline during the material conveying process, and assuring the separation of plastics and chemical fibers; an acidified anaerobic step for conveying the waste processed in the acidified anaerobic tank, where an acidified reaction area is above the inner cavity of the tank body of the acidified anaerobic tank, an anaerobic decomposition area is below the inner cavity of the tank body, and in the acidified anaerobic tank, the waste in the acidified reaction area comprises a dry acidifying layer over the liquid level and a wet acidifying layer; an anaerobic decomposition area comprises a floating layer located on the upper layer of the anaerobic decomposition area, a suspension layer located on the intermediate layer of the anaerobic decomposition area, and a heavy matter sediment layer located on the bottom layer of the anaerobic decomposition area, a one-way feed port is arranged corresponding to the upper part of the acidified reaction area on tank body, the waste coming from the one-way feed port is scattered uniformly on the upper surface of the acidified reaction area, a heavy matter discharge port is arranged on the bottom of the anaerobic decomposition area, the heavy matter discharged from the heavy matter discharge port enters the sediment cleaning device, the first solid/liquid discharge port is arranged on the lower part of the anaerobic decomposition area, the second solid/liquid discharge port is arranged on the middle upper part of the anaerobic decomposition area, a methane gas outlet is also arranged on the top of the tank body and is connected to the methane gas collecting tank by the pipeline, and a liquid inlet is also arranged on the tank body; a selection separation step for respectively conveying the materials discharged from the first solid/liquid discharge port and the second solid/liquid discharge port of the acidified anaerobic tank to the screening device, in which the solid is rolled, the organic waste is further crushed, the plastics and chemical fibers are separated out and are recycled, where the methane solution mixed with decomposed waste to the next step, and the step is performed in a closed space; a buffering adjusting step for temporarily storing the methane solution mixed with anaerobic waste in a buffering adjusting tank provided with a liquid inlet for receiving the methane solution, a liquid refilling port for receiving liquid produced by other steps, a water refilling port for receiving the external refilled water and a methane solution outlet for supplying liquid to the next step, where the step is performed in a closed space provided with a methane gas outlet connected to methane gas collecting tank by the pipeline.