The preceding separating technology of municipal solid waste is the premise and key to realizing waste comprehensive treatment and improving resource utilization. To the low efficiency of paper and plastic's separation, using the basic structural parameters of Horizontal air-separator, a finite element model is established based on Gambit software. Targeting at the pressure distribution and velocity distribution of the internal flow field under the condition of different wind direction and different wind speed, CFD is used for the analysis, and results shows that the wind angle between 15° and 20° and wind speed between 12 m/s and 14m/s is the optimum condition to get an ideal purity and efficiency of the light waste when winnowing domestic waste in the city of southern China.

Using the industrial wastes such as fly ash, phyllite and ove tails, the light ordinary type and high strength ceramsite are produced based on the different formulations by rotary kiln. The study is totally based on industrial wastes to produce new building materials. It is far-reaching practical significance for sustainable development of environment. Ceramsite is artificial light aggregate, which has the features of big surface area and light density, and widely apply in housing construction，road and bridge engineering etc. It is can place gravel as the main concrete aggregate in building structure to reduce the structural weight, improve the earthquake resistance of building structures, increase safety and durability of the structure. For road pavement, it can increase the wear resistance of the road. For wall materials, it is lightweight, high strength, maintain the temperature, heat insulation and sound insulation. It also used in buildings with its superiority, which has the functions such as fire-resistant, high temperature, anti-radiation.