New process for preparing high-purity magnesium oxide by normal temperature carbonization and low temperature pyrolysis

Abstract

The invention provides a new process for preparing high-purity magnesium oxide by normal temperature carbonization and low temperature pyrolysis. In the process, two calcining steps and one drying step are adopted, namely a high-purity magnesium oxide product can be obtained by calcining crude ore, hydrolyzing, carbonizing, drying and calcining; two external burning type rotary kiln calcining devices and system closed production are adopted; CO2 gas produced in a rotary kiln is collected and purified in a centralized way for carbonization; the waste heat of hot smoke produced outside the kiln is used for drying; the waste heat of a calcined hot material and vapor produced during the pyrolysis outside the kiln are used for pyrolysis; therefore, effective recycling of heat energy is realized, technical equipment are optimally matched and highly utilized, the heat energy is fully and effectively utilized, the product has high quality, the process is low in energy consumption and cost, has high benefit and is environmentally-friendly and suitable for calcining ores of various grades, such as magnesite, dolomite and the like.

Description

technical field [0001] The patent of the invention relates to a new process of normal temperature carbonization and low temperature pyrolysis of high-purity magnesium oxide; it belongs to the field of energy-saving kiln thermal chemical industry. Background technique [0002] The existing high-purity magnesium oxide process has layer-fired furnaces such as vertical grate furnaces, reverberatory furnaces, etc. for roasting, and then uses high-temperature carbonization and high-temperature hydrolysis, which has high requirements on coal quality, large coal consumption, complex carbonization process, and high cost. high. The product adaptability is poor, most of the equipment consumes high coal, and it is difficult to recover high-purity CO2. The environmental protection facilities are poor, the working conditions are bad, and the pollution is serious. The production process is mostly manual operation, poor safety performance, lack of comprehensive utilization of all links fr...

AI Technical Summary

Problems solved by technology

[0002] The existing high-purity magnesium oxide process has layer-fired furnaces such as vertical grate furnaces, reverberatory furnaces, etc. for roasting, and then uses high-temperature carbonization and high-temperature hydrolysis, which has high requirements on coal quality, large coal consumption, complex carbonization process, and high cost. high

Poor product adaptability, most equipment consumes high coal, and it is difficult to recover high-purity CO2

Poor environmental protection facilities, poor working conditions and serious pollution

The production process is mostly manual operation, the safety performance is poor, and the comprehensive utilization of all links from mineral raw materials to processing and utilization is lacking.

Low product quality and poor stability

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