Method for recycling return sand in soda ash production

Abstract

The invention relates to the technical field of soda ash production, in particular to a method for recycling return sand in soda ash production, which comprises the following steps of: mixing the return sand and gravels, feeding the mixture into a kiln, and calcining the mixture to obtain quick lime. Return sand can be recycled to obtain raw materials for the soda ash preparation process, so thatresource waste is eliminated, profits are increased, environmental pollution is reduced, and huge economic benefits are increased for enterprises.

Description

technical field [0001] The invention relates to the technical field of soda ash production, in particular to a method for recycling sand returned in soda ash production. Background technique [0002] At present, the quicklime CaO manufacturing process in the production process of soda ash (sodium carbonate) is affected by factors such as limestone (calcium carbonate) particle size, calcination temperature, calcination time, ventilation uniformity, and impurity nodules. 3 It cannot be completely decomposed, which eventually leads to a large amount of solid waste returning to sand after the digestion of quicklime CaO (a soda ash plant with a scale of 1 million tons of soda ash per year can produce about 300 tons of returning sand with a particle size of 10mm<40mm per day). Due to the small particle size of this part of the returned sand, it is easy to burst when heated, and it contains a large amount of carbon nuclei, magnesium-aluminum-silicon-ferrosilicon compounds, and t...

AI Technical Summary

Problems solved by technology

[0002] At present, the quicklime CaO manufacturing process in the production process of soda ash (sodium carbonate) is affected by factors such as limestone (calcium carbonate) particle size, calcination temperature, calcination time, ventilation uniformity, and impurity nodules. 3 It cannot be completely decomposed, which eventually leads to a large amount of solid waste returning sand after the digestion of quicklime CaO (a soda ash plant with a scale of 1 million tons of soda ash per year can produce about 300 tons of returning sand with a size of 10mm<particle size<40mm)

Due to the small particle size of this part of the returned sand, it is easy to burst when heated, and it contains a large amount of carbon nuclei, magnesium-aluminum-silicon-ferrosilicon compounds, and tumor slag, which leads to the uncontrollable coke ratio of raw materials, seriously affects the kiln ventilation, and the temperature is out of control. Large-scale nodulation, currently All major soda ash plants have adopted fixed-point stacking or dam-building for the returned sand of this particle size. However, these two methods not only do not generate any income, but require a transportation fee of about 6-8 yuan per ton, with 1 million tons Calculated on the scale of soda ash, if the above-mentioned returned sand is converted into raw material limestone at 100 yuan / ton, then about 10 million yuan will be wasted throughout the year! Especially in recent years, the price of limestone has been rising continuously, which has caused the cost of soda ash to continue to increase. In addition, the low activity and slow pulverization of the returned sand have caused huge pollution to the environment.