The dolomite calcination is one of the main part in the production of metal magnesium by silicon thermal process, and dolomite calcining kiln is a kind of important magnesium production line equipment. Rotary kiln, vertical kiln, tunnel kiln and boiling furnace are all belong to dolomite calcination equipment. Rotary kiln which is used in dolomite calcination is an important thermal equipment, and high-temperature flue gas in the calcination process and equipment cooling carried away a lot of energy. If we do not produce recycle and utilization of high-temperature flue gas in the production process and discharge flue gas arbitrarily, which not only pollute the environment but also waste a great of energy.

Due to the high-temperature flue gas produced in the process of dolomite calcining kiln calcination contains a lot of calories, therefore, the magnesium production enterprises to try their best to find ways to carry out technical transformation and recycle the rotary kiln flue gas according to the development trend and technological requirements of magnesium. There are two main ways as following.

1 Set the waste heat boiler in the rotary kiln inlet and provide steam produced by waste heat boiler for the reduction of the workshop jet pump vacuum system.

Although a part of the heat in the flue gas can be recovered by disposing a waste heat boiler in the rotary kiln inlet, there are also some problems. The main problem is that a longer flue is needed, flue insulation and flue sealing require more refractory materials and thermal insulation materials which lead to an increase of investment. At the same time, due to the flue gas temperature drop in the flue will cause heat loss, coupled with the waste heat boiler flue gas temperature is still high, up to 300 degrees centigrade, the utilization rate is low which using waste heat boiler to recover flue gas heat. In addition, there is another problem about shortage of steam or steam whereabouts. Therefore, the use of waste heat boiler to recover the flue gas heat is not the best way to save energy.

2 Set vertical preheater at rotary kiln inlet and preheat dolomite with flue gas

Adopting this calcination process not only greatly shorten dolomite calcination time in the kiln and improve the per unit area of production capacity, but also can get higher degree activity of calcined dolomite white thereby improve the return rate of magnesium. Most of new or technological transformation metal magnesium plant are using this technology. From the point of the enterprise feedback opinion, the rotary kiln with vertical preheater can reduce the energy consumption per ton of calcined white product from 270 kg to 180kg, and energy saving effect can reach 30%, while rotary kiln production capacity is increased by about 35%. This new type rotary kiln is more energy-saving than the ordinary rotary kiln, and the environmental protection index is better than that of the ordinary rotary kiln.

The heat is taken away by the high-temperature flue gas of dolomite calcination, which accounts for about 30% of the total energy consumption. The recycling and utilization of this part of the waste heat is very important for many magnesium production enterprises in terms of economic and environmental benefits. There are two main ways to waste heat utilization, but the rotary kiln with vertical preheater equipment is more conducive to energy conservation and emission reduction. The magnesium plant can give priority to this method because of high rate of heat utilization.

ZK is a professional rotary kiln manufacturer in China, which has a wealth of experience and advanced technology in rotary kiln design and production. Rotary kiln with vertical preheater produced by our company has won high praise of the domestic and foreign customers. If you want to get rotary kiln price, please contact us.