NOVELTY - System comprises a drying device, whose output end is connected with a mixing and pelletizing device, and an intermediate temperature carbonization device connected to the output end of the mixing and pelletizing device. The intermediate temperature carbonization device is respectively provided with a solid coke discharge outlet, a liquid tar discharge outlet, a wood vinegar liquid discharge outlet and a flammable gas discharge outlet. The solid coke discharge outlet is connected to an aeration tank. The liquid tar discharge outlet is connected to an input end of mixing and pelletizing device.    USE - The system is useful for treating municipal sludge (claimed).    ADVANTAGE - The system: has good processing efficiency; does not result in secondary pollution; utilizes less energy; and completely recovers the products, which can be comprehensively used.    DETAILED DESCRIPTION - System comprises a drying device, whose output end is connected with a mixing and pelletizing device, and an intermediate temperature carbonization device connected to the output end of the mixing and pelletizing device. The intermediate temperature carbonization device is respectively provided with a solid coke discharge outlet, a liquid tar discharge outlet, a wood vinegar liquid discharge outlet and a flammable gas discharge outlet. The solid coke discharge outlet is connected to an aeration tank of the municipal sewage treatment plant through a pipe. The liquid tar discharge outlet is connected to an input end of the mixing and pelletizing device through a pipe. The wood vinegar liquid discharge outlet is connected to an anoxic tank through a pipe. The flammable gas discharge outlet is connected to an input end of the drying device through a pipe. The solid coke after collecting is quantitatively dosed into the aeration tank of the municipal sewage treatment plant. The liquid tar after collecting is added at the input end of the mixing and pelletizing device. The wood vinegar liquid after collecting is quantitatively dosed into the anoxic tank of the municipal sewage treatment plant.