Classified reduction gasification iron smelting process of iron ore powder and coal powder in a Y-type entrained flow bed

A classified reduction gasification iron smelting process of iron ore powder and coal powder in a Y-type entrained flow bed, comprising the following steps:

• (1) uniformly mixing a pre-reduced iron ore powder based on Fe2O3 and the coal powder based on carbon according to the molar ratio 1:1.1-4 of C:Fe2O3 to obtain a mixture of pulverized iron ore and coal, and delivering the mixture to a powder silo;
• (2) spraying the mixture of pulverized iron ore and coal, a gasification agent and water vapor into a gasification segment respectively through a top nozzle and a plurality of radially tilted side nozzles disposed in a gasification furnace in the Y-type entrained flow bed, and performing combustion and gasification at a temperature of 1,500-1,800° C. to produce crude syngas and slag;
• wherein, during the combustion and gasification, the mixture of pulverized iron ore and coal, the gasification agent and water vapor sprayed from the top nozzle and the side nozzles collide, ignite and turbulently mix with each other at a combustion chamber center of the gasification segment to form a rotational strike and reaction zone;
• a residual ash-slag generated in the combustion and gasification is thrown toward the furnace wall of the gasification segment and swirled downward, the residual ash-slag having a residence time in the rotational strike and reaction zone of 10 s or more;
• and the residual ash is solidified on a water-cooled wall of the gasification segment to form a slag layer;
• (3) flowing the crude syngas and slag to a slag-iron separation segment through a gasification product exhaust port disposed at a center of a conical head of the gasification segment;
• unreacted iron ore powder and coal powder in the slag are further subjected to a reduction reaction in the slag-iron separation segment to obtain molten iron and CO, and the slag subjects to a sedimentation and separation process to separate molten iron and iron slag, wherein the iron slag is discharged through a slag outlet, and the molten iron is discharged via a siphonic molten iron outlet;
• the crude syngas is discharged from a coal gas outlet disposed at the top of the slag-iron separation segment, the crude syngas has a temperature of 1,500-1,800° C.;
• and
• (4) sucking a raw material iron ore powder to enter a riser to perform preheating, drying and partial reduction by the crude syngas discharged from the step (3);
• pre-reduced iron ore powder is separated from the top of the riser, and returned back to the step (1) so as to mix with the coal powder;
• the tail gas separated from the riser is purified and then supplemented for combustion, and the waste heat is recovered and utilized.