The pollutants in the slaughterhouse wastewater are mainly coming from blood, fat, animal hair, undigested food, feces, etc. The main pollutant in slaughterhouse wastewater is organics. Firstly by using a dissolved air flotation machine to remove the large amount of suspended matter and then by package sewage treatment plant to remove BOD5, COD and NH3-N from the water, we can finally create an organic fertilizer after dehydrating the sludge from the previous steps by using a volute screw press.