FORMATION OF FLUIDIZED BED FOR REDUCTION OF IRON ORE PARTICLES (VERSIONS) AND METHOD OF REDUCTION OF IRON ORE PARTICLES (VERSIONS)

摘要

FIELD: reduction of iron ore particles. SUBSTANCE: device for efficient reduction of fine iron ore with particles of wide range sizes includes melting gasifier and successively connected furnace for drying and preliminarily heating, reducing furnace for preliminary reduction, and also reducing furnace for final reduction. Each furnace is operated with fluidized bed and connected with cyclone for trapping iron ore dust contained in effluent gases. Each furnace is conical in shape and formed of joined with one another, copper cylindrical section, middle conical section and lower cylindrical section with height exceeding the furnace inner diameter in lower part of this section by 5.0-9.0 times and height of each upper section exceeding inner diameter of respective conical section in its upper part by 2.0-4.0 times. Furnaces are interconnected by gas and transportation pipelines and with cyclones by means of lines for return of trapped dusty fraction of ore to its own furnace. Gas velocity in zone remote from furnace walls is maintained with 1.0-3.0 minimal gas velocities required for suspension of medium-size particles in fluidized state. Temperature is 800-900 C and pressure is 2-4 atm and their drop in each furnace is 30-80 C and 0.3-0.6 atm, respectively. Time of resistance in furnaces is from 30 to 50 C min. EFFECT: significant reduction of taking out of ore fine furnace, increased reduction efficiency and improved utilization of reducing gas. 15 cl, 2 dwg