Working Principle of New Type phosphorous Gypsum Drying Equi

Problems exists in traditional phosphorous gypsum drying machine
Building gypsum production line by using phosphorous gypsum as raw materials:  this production line adopts countercurrent rotary kiln to finish drying and calcining. It uses coal and flue gas as heat source. Crushing, drying and calcining process can be finished at rotary kiln one time. The inlet temperature is controlled at 800 degrees and outlet temperature is controlled at 170 degrees.
Existing problem

1. Unstable drying quality: this process adopts middle-temperature calcining production line. Affected by moisture fluctuation and fuel, product components are not so reasonable. Therefore, traditional process cannot meet requests for gypsum products. Therefore, the application range of gypsum powder is limited. There will be series of quality problems arising, which will affect the sales of gypsum powder.

2. Small output capacity and high energy consumption: owing to the integration of drying and calcining, drying and calcining time are short. Dry basis in gypsum handling capacity per hour is only 18 to 20 tons and wet basis is 26 ton per hour. Annual output is about 150000 tons. The designed capacity, 200000t/a, cannot be achieved. Because of small output capacity of gypsum powder, coal consumption, 85kg/t, is much higher than two-stage methods in same industry.

3. Bad calcining quality: there are lumps in phosphorous gypsum residues. During loading process, lumps are inclined to enter dryer through grates and belt, which leads to over burning and under burning problem. Owing to the existing of lumps, gypsum cannot be fed stably. Due to short working time, feeding quantity and calcining temperature cannot be adjusted timely. Also, gypsum powder cannot be calcined evenly. 

Working principle of new phosphorous gypsum calcining and drying process
Air-swept dryer adopts the most advanced drying technology. It can almost deal with any kinds of materials, from lows-solid contents to low-moisture powder. Materials’ routine in dryer can be easily controlled. Therefore, this drying system can be used to produce dry fine powder and moist granular materials. There are three separate zones set in the drying system. Central retention zone decides the residual moisture and physical size of final products. Although this drying system adopts high temperature difference, but same with majority instant dryers, products’ temperature is lower than wet ball humidity. Heat source of this dryer can adopt oil-fired or gas-fired hot air fan. Generally speaking, heat source device is always integrated with drying cylinder. Products can enter terminal region directly from drying tubes. Final products can be collected by separator and bag filter. This series of dryer contains 9 sizes. Evaporation speed can reach as high as 8ton per hour.