（一）sludge sun-drying place
　　The design of structure has three functions: surface evaporation, bottom leakage, and middle releasing. Drying time is different according to different condition of nature and sludge sun-drying place. The key point is address and design of the sludge sun-drying place.
　　Advantages of sludge sun-drying place: sample. Sludge water ratio is low. (65%-75%) disadvantages: it uses many areas, and has bad sanitary condition. Big labor intensity is needed for accessing.
（二）sludge filter press machine
　　1.vacuum filter machine
　　2.pressure filter machine (plank filter press machine)
　　3.vacuum rotor filter machine
　　4.belt rolling filter machine
　　5.centrifugal dewatering machine
（三）applied range of filter press machine
　　It is proper for treatment of city live waste water, printing and dyeing textile, galvanization, paper making, leather, brewing, food processing, coal washing, chemistry, metallurgy, medicine, and porcelain. It is also proper for solid and liquid segregation and liquid leaching process in industrial production.