CN86105494A

CN86105494A - Brown coal pre-reduction of ore direct steelmaking stocking

Info

Publication number: CN86105494A
Application number: CN 86105494
Authority: CN
Inventors: 刘宗周; 王静涵; 杨式蘅; 罗海荣; 杨晓源; 史加沦
Original assignee: KUNMING POLYTECHNIC COLLEGE
Current assignee: KUNMING POLYTECHNIC COLLEGE; Kunming University of Science and Technology
Priority date: 1986-08-27
Filing date: 1986-08-27
Publication date: 1987-07-08

Abstract

Brown coal pre-reduction of ore direct steelmaking stocking is a kind of novel process of ferrous metallurgy, and it and existing blast furnace-converter relatively have without coke, save blast furnace, coke oven, do not need the advantage of sintering and coking process.Grasping operation, controlling well and utilize brown coal inferior and massive ore to obtain pre-reduction of ore direct steelmaking stocking under the technical qualification in the kiln.Coal gas that produces in the reduction process and semicoke also can utilize, and energy-conservation energy-saving efficiency is remarkable.

Description

Brown coal pre-reduction of ore direct steelmaking stocking

A kind of ferrous metallurgy method.Be to lack coking coal, but high-grad iron ore deposit is arranged, a novel process of the area development Iron and Steel Production of brown coal inferior.

According to the whole nation in 1985 directly reduction meeting material " direct reduction of iron ore specific index " retrieved 1973 to the periodical of relevant directly reduction of nineteen eighty-three and product utilization and retrieved the world patent document in nearly ten years and learnt at home and abroad there is no and use the low-quality brown coal that massive iron ore is carried out direct reductive report in rotary kiln.

Blast furnace ironmaking is fairly perfect on technology, but must use high grade coke.Coking coal resource only accounts for 5～10% of coal resources in the world, and it is also extremely inhomogeneous to distribute.For the countries and regions that lack coke resource and steel scrap, it is feasible and favourable adopting the present invention to produce sponge iron, and technological process both need not expensive coke, can obtain the low sponge iron of matter high price again, remedy the deficiency of steel scrap.

Technical process of the present invention as shown in Figure 1.

Ferrous grade is broken to granularity less than 40 millimeters greater than 60% massive iron ore, and brown coal are crushed to granularity less than 50 millimeters, limestone crushing to 0～5 millimeter (when the content of sulphur in the coal can not add Wingdale less than 1% the time).According to iron ore: add by the rotary kiln afterbody after the ratio batch mixes of coal=1: 1.5～2.0, along with the rotation furnace charge of rotary kiln is moved by kiln Caudad kiln hood direction, it is that 0～3 millimeter fine coal supplies burning that kiln hood sprays into granularity by coal spouting gun, and temperature is controlled at 900～1100 ℃.Iron ore falls in the cooling cylinder through the fixedly sponge iron that gives heat, drying, reduction output in kiln, wait to be chilled to below 100 ℃ and separate through the belt magnetic separation, partly semicoke can be used as and returns coal or reductive agent use, and sponge iron is directly by electric-arc furnace steelmaking, and casting thereafter is sent to steel rolling and is become a useful person.

As the fuel of this law and the coal of reductive agent, preferably contain fixed carbon greater than 25%, ash is less than 20%, and calorific value is not less than 4000 kilocalories.

Rotary kiln can use the stove shape after improving of being recommended as accompanying drawing 2, and there are three rifles at the kiln hood place, and 1 is coal spouting gun, and effect is that coal and air mixed are sprayed into the heat supply of kiln internal combustion then.2 for throwing the coal rifle, and the telescopic level of regulating this rifle drops into granular reductive agent kiln hood or kiln middle part, toppedly plays anti-oxidation on ore bed, increases and reduces, and can prevent ring formation again.3 is jet gun, can spray into steam or reducing gas in the kiln, and the hydrogen of generation and carbon monoxide had both strengthened reducing atmosphere in the kiln, can regulate the kiln temperature again, kiln exhaust gas body composition carbon monoxide (CO) 0.5～16.4%, carbonic acid gas (CO ₂) 10～31.8% oxygen (O) 0～8.6%.Build filling ratio that collet 4,5 its role is to improve rotary kiln at 1/3rd and 2/3rds kiln inwall places of kiln height degree respectively, improve bed thickness, favourable ore drastic reduction, collet height be internal diameter 1/5th to sixth.

The invention process result obtains the degree of metalization of following technico-economical comparison, pre-reduction of ore greater than 80%, and the utilization coefficient of rotary kiln is greater than 0.4 ton/Mi Ri, and total consumption of coal is lower than 2 tons of/ton ore deposits, and the sponge iron cost is lower than 950 yuan.

Compared with prior art have the following advantages.

1. save blast furnace and coke oven, do not need sintering and coking process, both having saved the capital investment cost also has reduction significantly.

2. can enlarge coal resource in the utilization aspect the metallurgical industry directly into stove (without coking coal) with brown coal inferior, coal gas that produces in the process and lignite semi-coke also can utilize, and be energy-conservation, energy-saving efficiency is remarkable.

3. if adopt closed circuit, dry gas cleaning way to handle flue dust and waste gas, can remove pollution basically to environment.

Claims

1, a kind of metallurgical method of brown coal pre-reduction of ore direct steelmaking stocking, raw material is through batching, mix, give handling and obtain intermediates, again through Electric furnace steel making, the rolling steel that obtain, it is characterized in that said pre-treatment is to produce sponge iron with brown coal prereduction massive iron ore in rotary kiln, be about to ferrous grade and be crushed to granularity less than 40 millimeters greater than 60% iron ore, brown coal are crushed to granularity less than 50 millimeters, according to iron ore: the ratio batching of coal=1: 1.5～2.0, mix the back and add (when the sulphur content of coal can not add Wingdale less than 1% the time) by the rotary kiln afterbody, along with the rotation furnace charge of rotary kiln is moved by kiln Caudad kiln hood direction, kiln temperature is controlled at 900～1100 ℃, and iron ore process in kiln is given heat, do behaviour, reduction obtains solid-state sponge iron and discharges from kiln hood.

2, the metallurgical method described in claim 1 is characterized in that the rotary kiln head is equipped with three spray guns, and middle one is coal spouting gun, and one in upper right side is throwing coal rifle, and one on upper left side is a jet gun.

3, it is characterized in that as claim 1 and 2 described metallurgical methods rotary kiln built collet by laying bricks or stones at kiln height degree 1/3rd and 2/3rds inwall place, the collet height be internal diameter 1/5th to sixth.

4, the metallurgical method described in claim 1 is characterized in that the brown coal composition contains fixed carbon greater than 25%, and ash content is less than 20%, and calorific value is not less than 4000 kilocalories.