NOVELTY - Producing lactic acid involves separating cellulose as raw material from agriculture and forestry waste by using a separation device for implementation. The primary material is radially cut and put into the machine for crushing. The crushing process is completed by a blade set with ridge vertical wall of the cylinder body and the material sinks at the bottom of the crushing chamber which is then hammered. The finished material is broken continuously through hammering, extruding and crushing. The crushed particle exit through the baffle plate when the screen has smaller pore size.    USE - Method for producing lactic acid (claimed).    DETAILED DESCRIPTION - Producing lactic acid involves separating cellulose as raw material from agriculture and forestry waste by using a separation device for implementation. The primary material is radially cut and put into the machine for crushing. The crushing process is completed by a blade set with ridge vertical wall of the cylinder body and the material sinks at the bottom of the crushing chamber which is then hammered. The finished material is broken continuously through hammering, extruding and crushing. The crushed particle exit through the baffle plate when the screen has smaller pore size. The ultrasonic waves enters into the room for loosening the material microstructure. The material is passed to the discharging mouth by using screw conveyor belt and the material then enters in rotary expanding tearing device for heating. The crushed material is treated at variable pitch of screw rod extrusion, friction and high temperature. The temperature and pressure of the system are raised continuously. The material volume in rotary expanding tearing device is compressed continuously and the material instantaneously expands because of reduced pressure. The safety explosion-proof valve is opened and steam is ejected when the pressure exceeds a pre-set value for a safe operation. The material then enters in the microwave pipe and microstructure material is obtained because of faster molecule movement. The petty molecule structure of material fiber is damaged and the material enters the rotary material separating device. The microwave broken material are kept under the action of water so that lignin and cellulose are separated from the decomposed water-soluble hemicellulose. The cellulase breaks down in the presence of biological enzymes for the benefit of the lactic acid fermentation of short-chain carbohydrates and dissolution. The separated lignin, cellulose and hemicellulose dissolved in water flows into the liquid collection device from a liquid outlet. An INDEPENDENT CLAIM is included for a decomposing and separation device, which included a control panel connected with the primary material crushing device through pipeline, material expanding tearing device, material crushing device and microwave decomposing material separating device where the material primary crushing device comprises an L-shaped tube provided at side wall with radial hopper and the internal vertical tube is set with smashing machine where the smashing mechanism set with incline material plate, the incline material plate and inner end horizontal tube are set with hammering device, the hammering device is set with cylinder wall vertical to the baffle plate where a material flow outlet is set between the lower end of the baffle plate and cylinder wall, an outlet to flow through screen, inner wall is set up with ultrasonic generator and connected with ultrasonic wave room set with speed reducer and connected with the feeding screw rod A.