Efficient energy-saving calcining system for kaolin

Abstract

The invention discloses an efficient and energy-saving calcining system for kaolin. The efficient and energy-saving calcining system comprises a calcining rotary kiln, a combustion chamber, a raw material bin, a wall cooler and a storage bin, a kiln cover covers the outer wall of the wall cooler in the length direction of the wall cooler, an air outlet is formed in the side wall of the kiln cover and communicated with an air inlet of an induced draft fan through a pipeline, and an air outlet of the induced draft fan is communicated with a primary air inlet and a secondary air inlet of a combustor through pipelines respectively. The system disclosed by the invention has the beneficial effects that heat energy recovery is realized, the use amount of gas fuel by a combustor is reduced, the production cost of an enterprise is saved, energy conservation and consumption reduction are realized, the situation that mullite impurities in a kaolin finished product are excessive is avoided, the amount of screen residues is reduced after screening, the yield of the kaolin finished product is increased, and the production cost is reduced. Therefore, the economic benefits of enterprises are improved, the decarburization efficiency is effectively improved, and the product quality is improved.

Description

Technical field: [0001] The patent of the invention belongs to the technical field of kaolin calcination, and specifically relates to a high-efficiency and energy-saving calcining system for kaolin. Background technique: [0002] Kaolin finished product is an ultra-white and ultra-fine powder, which is mainly used in papermaking, ceramics, medicine, ink and paint, etc., and has a very wide range of uses. At present, the kaolin finished product is obtained by calcining the gangue through a rotary kiln at a high temperature of 950-1100 °C, dehydroxylation, decarburization and whitening. The kiln head of the calcining rotary kiln is connected with a combustion chamber through the kiln head cover, and the burner at the head of the combustion chamber emits flame, so that high temperature air is formed in the combustion chamber and enters the calcining rotary kiln to calcine and pulverize the pulverized coal gangue; The kiln tail of the kiln enters the kiln and gradually moves to...

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Problems solved by technology

[0003] However, the above-mentioned calcination method has the following problems: 1. The temperature of the outer flame of the flame ejected from the burner is as high as 1700°C, and it is very easy to directly contact the kaolin in the kiln hood through the combustion chamber, which not only forms a large amount of impurities, but also after screening, A large amount of sieve residue is produced, which reduces the output of kaolin finished products; it will also destroy the crystal structure of kaolin products themselves, reduce their quality, and affect the economic benefits of the enterprise; 2. The connection between the calcined rotary kiln and the kiln hood is very easy Heat loss occurs, which in turn increases the use of gas fuel by the burner, resulting in an increase in the production cost of the enterprise; 3. The finished kaolin after high-temperature calcination needs to be cooled, and the cooling method is that the finished kaolin after high-temperature calcination is sent to The outer wall of the wall cooler is cooled by natural wind in the wall cooler. At present, the enterprise has not recovered the heat carried by the calcined kaolin finished product, which is not conducive to the energy saving and consumption reduction of the enterprise, and affects the economic benefits of the enterprise; 4. The inner wall of the existing calcining rotary kiln is equipped with straight plate-shaped lifting refractory bricks, which have low bearing capacity, are easy to break, and have a short service life. Moreover, during the operation of the calcining rotary kiln, the lifting range of the lifting refractory bricks is smaller than that of the calcining rotary kiln body. The quarter circle of the kiln has a small range of spreading materials and a low height, resulting in relatively concentrated raw materials in the kiln body, poor contact with the secondary air, low decarburization efficiency, and poor product quality; in order to ensure product quality, the measures currently taken It is to reduce the amount of raw material input or increase the temperature, and the reduction of raw material input directly leads to a decrease in output; while increasing the temperature not only leads to high energy consumption, but also the concentration of raw materials will make it difficult to diffuse the heat generated by the decarbonization reaction, resulting in high local temperatures. Directly destroy the crystal structure of the product, but lead to a decline in product quality

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