The main structure is the sludge drying field, a flat land surrounded and separated by earth embankment, if the soil permeability is poor, can be paved with thin layer of gravel and sand, and set up drainage dark pipe. Reducing the water content of sludge deposited on the field by infiltration and evaporation. The process of infiltration can be completed in about two to three days, and the moisture content can be reduced to about 85 percent. After that, it relies mainly on evaporation, which can drop to about 75 percent in a few weeks. The dehydration effect of sludge drying field is affected by local rainfall, evaporation, temperature, humidity, etc. Generally suitable for dry, less rain, sandy soil areas used.