In order to improve the extraction rate of Magnesium Oxide MgO and reduce the energy consumption of the product. To improve product quality and increase product variety, the double-subtractive carbonization process mainly changes the carbonization conditions and reduces the production process with high energy consumption. The purified lime emulsion is carbonized under specific conditions, so that 80-90% of MgO is dissolved, and a supersaturated solution of MgO containing 20-30 g/L of MgO is generated. After rapid pressure filtration, under specific conditions, the saturated solution of magnesium carbonate is decomposed at 20 to 30 degrees to obtain basic magnesium carbonate. This basic magnesium carbonate filter cake has only 50-60% moisture content. Light Magnesium Oxide MgO products are obtained by calcination.

The process features:
(1) The extraction rate of Magnesium Oxide MgO is increased by 20-30%.

(2) The compression and pyrolysis processes are subtracted, and the moisture content of the basic magnesium carbonate filter cake is reduced by 25-30%.

Therefore, the coal consumption per ton of light Magnesium Oxide MgO product is reduced by 75%, and the electricity consumption is reduced by 65%.