Simulation analysis of flue-dust thermal treatment in microfluid furnace

Abstract

Caustic and sintered magnesia are the main products of magnesite thermal treatment. Caustic magnesia is generated by decomposition of MgCO3 to MgO and CO2. Sintered magnesia is generated at high temperatures at which a liquid phase is produced. Caustic magnesia is broadly used product. Because of high basicity, MgO is very convenient for reduction of water and environment acidity. The production of caustic magnesia is currently performed in rotary and multistage furnaces. The production in rotary furnaces comes with a high quantity of flue-dust - up to 35 %. The flue-dust consists of calcinated and partially calcinated particles and of magnesite dust particles with a high proportion of MgO. The flue-dust generated by current technology is captured in dust chambers, cyclones and fiber filters. The captured material is partly used for sinter magnesia production. Rest of the material is commercialized as waste with adequate low prices. In the developing technology, dust is separated from flue-gas and is directly treated in the microfluidic furnace. In the present development stage, the mathematical model of microfluidic furnace based on elementary balance method was created. A model adequacy was carried out on experimental furnace. The pilot microfluidic furnace was developed based on the simulations. The experiments of the flue dust calcination of rotary furnace were executed.