Refractory Materials for Magnesium Reduction Furnace

Large-scale energy-saving magnesium reduction furnaces use silicon thermal method to smelt magnesium. The process of magnesium reduction is the process with the lowest efficiency and the highest energy consumption in the silicon thermal method. Therefore, energy saving and consumption reduction of magnesium reduction furnaces are of great significance. The main reason for the low thermal efficiency of the reduction furnace is the high exhaust gas temperature, which is as high as 1150~C and close to the furnace temperature. To improve the thermal efficiency of the reduction furnace, it is necessary to fully recycle the waste heat of the flue gas.

Thermal storage combustion technology uses the heat absorption and heat release of high-efficiency heat storage bodies to recover the physical heat of high-temperature flue gas to the extreme, preheat the air and coal gas, and reduce the exhaust temperature of the flue gas from 1150~C to about 150~C. The temperature of the air and coal gas entering the furnace increases from room temperature to about 1000℃. It can recover more than 80% of the energy taken away by the flue gas, greatly improving the thermal efficiency of the reduction furnace. Air and gas preheated at high temperature can burn at low oxygen concentration. Low oxygen concentration reduces the average combustion speed, expands the combustion boundary, forms a uniform temperature field, and reduces the concentration of NO. Furnace temperature uniformity is the first factor to ensure the magnesium production rate and magnesium reduction quality of the reduction furnace. Only when the furnace temperature is uniform can the magnesium reduction furnace develop towards large-scale development.