What are the shortcomings in the production of high-purity magnesia

Before the 1980s, in the past 30 years, the production of high-purity magnesia was mainly undertaken by Anshan Iron and Steel’s Dashiqiao Magnesium Mine. Vertical kilns of 25 cubic meters, 32 cubic meters, 40 cubic meters, 47 cubic meters, and 55 cubic meters were selected successively, using coke as fuel. , Using magnesite as raw material. A one-step calcination method was used to prepare heavy calcined magnesia containing 92% magnesia and was used as a national artificial production. Brick is the raw material for open-hearth steelmaking. 96 Fused Magnesia.

The disadvantages of the process of producing high-purity magnesia are: low utilization rate of ore, fine-grained ore cannot be used; high impurity content and high ash content in coke will pollute magnesium oxide, thereby increasing the content of SiO2 and AlO3 in magnesium oxide, and the content of magnesium oxide It can only be guaranteed at about 92%; the continuous operability is poor, and the small particles of magnesite adhere to the kiln wall during the thermal decomposition process, and the materials in the kiln are easy to agglomerate to form the kiln body. Changes in material flow and thermal indicators caused the failure of mechanized operation at the end of the overhaul.

The fine density of magnesite is low, and it is tropically decomposed in front of the kiln to release carbon dioxide and form light-burned magnesia, but its "parent salt illusion" still exists, which is not conducive to further refinement of magnesite. The volume density of sintered magnesite is only between 3.0g and 3.1g per cubic centimeter, which seriously pollutes the environment. Magnesite decomposes a large amount of carbon dioxide, and the flue gas after combustion is mixed with coke fine particles and coke fine particles. The light burned dust flying out of the kiln pollutes the environment, making the management of high-temperature flue gas difficult.

At present, my country's secondary and tertiary mines still use solid fuel shaft kilns to calcinate magnesia to produce high-purity magnesia. The magnesium oxide content is 90%~92%, and the volume is greater than 3.10 grams per cubic centimeter. Reburned magnesia is an important raw material for the production of ordinary magnesia bricks and refractory materials without shapes. The annual production in Liaoning Province is estimated at 2.5 million tons. Due to the use of the third mineral, the product price is low and there are shopping malls, and it is difficult to eliminate it now. Now, do you have a more detailed understanding of the production process of high-purity magnesia? If you have any other related questions, you are welcome to leave a message on the message board on our website, and we will give you a satisfactory answer.