CN1027546C

CN1027546C - Technique for steel-smelting from waste metal filings

Info

Publication number: CN1027546C
Application number: CN92112687A
Authority: CN
Inventors: 赵铁鉴
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-10-27
Filing date: 1992-10-27
Publication date: 1995-02-01
Anticipated expiration: 2007-10-27
Also published as: CN1076967A

Abstract

The present invention relates to a technological method for smelting steel from metal filings. In the present invention, raw materials, oil removing water, a fine raw material bin, a disk feeder and a direct-current electric furnace are adopted, and the technological steps of coarse sieving for selection, crushing, ball milling, fine sieving for selection, spiral stirring, coarse selection, concentration for lifting, fine selection, precipitation for dehydration, ball forming, sintering, slag discharging, tapping, finished product casting, etc. are adopted; and therefore, the recovery rate of the finished products of the wet materials containing the metal fillings, such as C, Si, Mn, Cr, Mo, V, W, etc. is 54.4%, and the recovery rate of the finished products of dry materials is 73.5%.

Description

Technique for steel-smelting from waste metal filings

The invention belongs to field of steel-making, particularly the recycling of scrap metal abrasive dust.

At present, the mechanical part of China's machinery manufacturing industry, precision prescribed and smooth finish are very high, all adopt grinding machine to carry out precision work.With grinding machine processing, a large amount of abrasive dust (being commonly called as the emery wheel end) of annual generation all goes out of use, and throws away as industrial refuse throughout the year, and this not only brings very large economy loss to society, causes huge waste to national resources simultaneously.According to the preliminary statistics, only, just produce more than 40,000 ton of abrasive dust per year in Harbin City's machinery industry.Contain valuable metallic element in the abrasive dust, as Cr, Mo, V, W, Ti etc.The method, the equipment that reclaim at present scrap metal bits steel-smelting are many, for example: with the method for steel scrap bits steel-smelting, application number: 88105088.1 it be the method for melting steel cuttings.

In order to recycle the scrap metal end effectively, the invention provides that a kind of power consumption is low, the rate of recovery is high, the processing method with steel-smelting from waste metal filings of less investment.

The object of the present invention is achieved like this:

Raw material is more than 18 ℃, more than 30 day naturally the dehydration or by drying oven 400～500 ℃ of temperature, dry more than 3 hours, carry out de-oiled water, behind de-oiled water, first via raw material (greater than the piece material of 3～5mm) enters crusher and carries out fragmentation, the second road raw material (greater than 1mm) behind de-oiled water enters ball mill, Third Road raw material (less than 1mm's) behind de-oiled water enters helical stir, the first via, the second road raw material enters and enters the fine screen sorting after ball mill is less than 1mm, choose at the fine screen branch and to add water and carry out abrasive dust and enter helical stir after the separating of emery wheel end ash in early stage, enter ragging again, carry out sorting by magnetic separator, the pure metal end directly enters the precipitation dehydration, and also available centrigugal swing dryer dries.Contain nickel, stainless steel, manganese, copper, aluminium etc. and belong to and do not inhale the magnetic metal species and enter shaking table, carry out sorting.Then enter the precipitation dehydration, enter by ragging and concentrate to promote, abrasive dust and cooling fluid are concentrated, and rise to the refining-sorting machine and carry out refining-sorting, after mud, the moisture of abrasive dust and emery wheel ash removed, correct grinding bits are sent into smart former feed bin by lift enter disk feeder with separating agent and mix, become compound after, enter nodulizer, in 1300～1500 ℃, carry out sintering after the balling-up, make the compound local melting, generate liquid phase, join and carry out the melting deoxidation in the direct current furnace.Before steel-making will be tapped, add additive less than 1%.Thereby slag tap earlier, back tapping, the direct current furnace processing sequence of slagging tap, tap all is to control toppling over of stove by hydraulic efficiency system, hydraulic efficiency system is made up of toothed gear pump, distribution valve, oil cylinder.Connect fly-ash separator when scalping sorting, ball milling, the work of separating agent storehouse.

The present invention has following advantage: power consumption is low, about melting steel abrasive dust per ton consumed power 1500 degree, and the metal recovery rate height, wet feed reclaims yield rate will be 54.4%, siccative reclaims yield rate will be 73.5%.Calculate by 380 tons of emery wheel ends at present, produce 200 tons on steel ingot, enterprise profit is 160,000 yuan.Use this steel ingot as returning the remelting steel scrap as steel mill, can add iron alloy less, add 52.5 kilograms in tungsten (mean value) less, be converted into 75 kilograms of ferrotungstens, 26,000 yuan of ferrotungstens per ton as steel per ton; Steel per ton adds 31.8 kilograms of molybdenums less, is converted into 57.8 kilograms of molybdenum-irons, 29,000 yuan of molybdenum-irons per ton, 22.5 kilograms of the few chromatizes of steel per ton are converted into 37.5 kilograms in ferrochrome, 4660 yuan in ferrochrome per ton, steel per ton adds 9.2 kilograms of vanadium less, is converted into 18.4 kilograms of vanadium iron, 58.500 yuan of vanadium iron per ton.When using this steel ingot melting as steel mill, metal charge per ton can add the alloy of above-mentioned quantity less, only to use 200 tons of calculating every year, can save 15 tons of ferrotungstens in 1 year, 7.5 tons of molybdenum-irons, and 3.68 tons of vanadium iron, this does not all consider alloy scaling loss amount.Then annual only this item steel mill can save 1,234,018.00 yuan, the equal energy source consumption of can economizing on electricity in addition, economize on coal.

Block diagram is a processing method block diagram of the present invention.

Below in conjunction with block diagram of the present invention in detail the embodiment of the invention and working process are described in detail:

Raw material abrasive dust (emery wheel end) generally is loose shape, and oil-containing (containing small amount of moisture) about totally 18.8% after measured, contains other impurity about 30%.Through at more than 30 day natural de-oiled water more than 18 ℃ (promptly in the open down stack) or after with rotary kiln or kiln dried, use the vibratory screening ragging: bulk impurity is that waste material is thrown away; Entering crusher in crushing greater than the block raw material of 3～5mm then enters ball mill and wears into and enter refining-sorting below the 1mm; Raw material greater than 1mm directly enters ball mill; Raw material less than 1mm directly enters helical stir, when vibratory screening carries out ragging, for the protection environmental health, carries out environmental dust removal with fly-ash separator.Choose at the fine screen branch, raw material less than 1mm enters helical stir, other is in helical stir, the following raw material of 1mm carries out abrasive dust and the separating of emery wheel ash in early stage, enters ragging then, carries out sorting with magnetic separator, pure metal is promptly dewatered by the precipitation that directly enters that magnetic separator sucts, the metal that can be magnetized that contains oil, ash then enters thickner, and raw materials such as nickeliferous, stainless steel then enter separation by shaking table, then then enters the precipitation dehydration.In concentrating lifting, carry out concentration, and rise to the refining-sorting machine.Lifting realizes with propeller pump.

Precipitation dehydration one is to use settling tank, takes off abrasive dust and emery wheel ash moisture content with certain hour, the 2nd, dry with centrigugal swing dryer, and be that pure abrasive dust is sent into smart former feed bin by lift through the smart raw material after the precipitation dehydration.The reductor that smart raw material comes with the separating agent storehouse, composite deoxidant, adjustment alloying element addition agent, remove in the molten steel additive such as harmful element agent join mix in the disk feeder after, enter nodulizer again, make the spherical sinter machine that enters in the diameter 30mm left and right sides, at 1500 ℃ of left and right sides sintering, make the ball local melting of compound, after generating liquid phase, add direct current furnace.But the ball that sintering comes out in the actual production is far longer than the needs of direct current furnace.After the sintering circuit cooling, particle is just formed bulk mutually.After before entering direct current furnace the bulk behind the sintering being warmed to 800～1000 ℃ by pot arch, entering and carry out melting in the direct current furnace, the purpose of heating is to reduce the steel-making time, simultaneously saves energy etc.Electric furnace adopts water-cooled to cool off, and adopts hydraulic efficiency system to slag tap, tap.Before steel-making will be tapped, add additive less than 1%, reach steel and separate, earlier tapping with slag.The back tapping.Slag after rolling, tapping is directly poured molten steel into the steel ingot car and is become steel ingot.

Claims

A kind of from the processing method that contains the abrasive dust steel-smelting of scrap metal, it is characterized in that: raw material is more than 18 ℃, through more than 30 days naturally the dehydration or by drying oven 400～500 ℃ of temperature, dry more than 3 hours, carry out de-oiled water, behind de-oiled water, enter crusher greater than the first via raw material of 3～5mm and carry out fragmentation, the second road raw material greater than 1mm behind de-oiled water enters ball mill, Third Road behind de-oiled water is less than the helical stir that enters of 1mm raw material, the first via, the second road raw material enters and enters the fine screen sorting after ball mill is less than 1mm, choose at the fine screen branch and to add water and carry out abrasive dust and enter helical stir after the separating of emery wheel end ash in early stage, enter ragging again, carry out sorting by magnetic separator, the pure metal end directly enters the precipitation dehydration, contain nickel, the material of stainless steel etc. or non-ferrous metal enters shaking table, carry out sorting, then enter the precipitation dehydration, enter concentrated the lifting by ragging, abrasive dust and cooling fluid are concentrated and rise to the refining-sorting machine carry out refining-sorting, the mud of abrasive dust and emery wheel ash, after moisture removes, correct grinding bits are sent into smart former feed bin by lift enter disk feeder with separating agent and mix, become compound after, enter nodulizer, in 1300～1500 ℃, carry out sintering after the balling-up, the compound part is dissolved, generate liquid phase, join and carry out melting in the direct current furnace, before steel-making will be tapped, add additive, thereby slag tap earlier, the back tapping separates slag.