CN102827972A - Blast furnace spray-blow coal technology using semi-coke of iron works - Google Patents
Blast furnace spray-blow coal technology using semi-coke of iron works Download PDFInfo
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- CN102827972A CN102827972A CN2012103241829A CN201210324182A CN102827972A CN 102827972 A CN102827972 A CN 102827972A CN 2012103241829 A CN2012103241829 A CN 2012103241829A CN 201210324182 A CN201210324182 A CN 201210324182A CN 102827972 A CN102827972 A CN 102827972A
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Abstract
The invention provides a blast furnace spray-blow coal technology using semi-coke of iron works. The technology comprises the following steps of: mixing semi-coke, anthracitic coal and bituminous coal based on a ratio; powdering the mixture in a mill, and carrying out spraying and blowing to a blast furnace for one time or multiple times through a blast furnace coal spraying system under a wind temperature of 1200 DEG C. With adoption of the technology, the semi-coke industrial application field can be further expanded; the industrial development can be sped up; the supply situation that the supply of the coking coal and the bituminous coal become tighter can be released through the semi-coke blast furnace spray-blow coal technology; and a benefit is provided to achieve the application and popularization of the coal carbonization technology; the bituminous coal can be replaced via the semi-coke, and the national current requirement on energy conservation and emission reduction can be met; and moreover, the economic benefit of the downstream enterprises can be obviously improved due to the low cost of the semi-coke.
Description
Technical field
The invention belongs to the recycle of production field of metallurgy resource comprehensive, be specifically related to a kind of pulverized coal injection into blast furna technology of utilizing blue charcoal.
Background technology
Pulverized coal injection in blast furnace can reach the reduction coke ratio, improves the purpose of output, has good economic benefits.National emphasis iron and steel enterprise in 2010 coal powder injection improves 10kg/t than being 145kg/t than the last year, realize national coal powder injection total amount more than 6,400 ten thousand t, and in February, 2011, domestic iron work seat pulverized coal injection ratio reaches 179.5kg/t, created go into operation since best level.Along with China's rapid development of economy; Coal price goes up year by year, causes the also corresponding increase of cost of pulverized coal injection, on the basis that reduces coke ratio; Reach the purpose that reduces production costs, the lower coal of price is constantly sought as the blast furnace blowing raw material by each Iron And Steel Plant.
Blue charcoal is that weak bonding or the dross coal with high volatile is raw material, through in the semicoke product of low-temperature pyrolysis charing after removing coal-tar middle oil material of coal and most of volatile, claim semicoke again.Because of this product flame when burning is blue look, so claim blue charcoal.Along with the continuous progress of state of the art, blue charcoal refines blue charcoal from soil gradually and develops into machine-processed blue charcoal.The blue charcoal of soil refining is simply backward because of its production technique, and manual operation can only rely on the fire extinguishing of the empiric observation duration and degree of heating, and quality can not get guaranteeing that fixed carbon content is wasted resource simultaneously about 82% generally speaking, and contaminate environment stops at the beginning of 21 century producing gradually.The blue charcoal of mechanism has adopted advanced destructive distillation sinter process; Fixed carbon content has improved 5~10 percentage points than the blue charcoal of soil refining, and ash content and volatile matter have reduced by 3~5 percentage points, steady quality; Moisture reduces, and physical strength also is significantly improved than the blue charcoal of soil refining.
Though coal resources in China is very abundant, it is also unbalanced to distribute, and concentrates on central and west regions mostly; Especially low volatile meager lean coal hard coal, big-and-middle-sized steel mill then majority is distributed in the eastern region, and this just causes low-volatile coal portion's transportation eastwards from the Midwest; Cost is higher, and it is the most western that Xinjiang is positioned at China, and iron and steel enterprise need consume a large amount of transportation cost to its blue charcoal Product transport to the east; And Jiuquan Iron & Steel Co. is nearer apart from Xinjiang with respect to other iron and steel enterprises, and this makes the wine steel select the blue charcoal in cheap Xinjiang to become possibility, adds transportation cost; The wine steel adopts blue charcoal also can not surpass 500 yuan/t as the price of showing up of blast furnace injection coal; Price far below adopting other steam coal and blue charcoal can save production cost greatly, creates economic benefit.
Along with China's rapid development of economy; Coal price goes up year by year, causes the also corresponding increase of cost of pulverized coal injection, on the basis that reduces coke ratio; Reach the purpose that reduces production costs, the lower coal of price is constantly sought as the blast furnace blowing raw material by each Iron And Steel Plant.Dragon steel iron work seeks to reach the dp that reduces the iron-smelting fuel cost, widens the ironmaking blowing coal resource with the lower blue charcoal instead of part hard coal of price.
Blue charcoal product has many purposes, is one of purposes than the tool development prospect as the blast furnace blowing raw material wherein.See recently that from sexual valence the quality of blue charcoal and performance are superior to hard coal and meager coal, meager lean coal; See from resource, the high-quality that is used to produce blue charcoal not agglutinating value(of coal) or weakly caking property high-volatile bituminous coal resource far away more than the high-quality anthracite that can be used for blast furnace blowing and meager coal, meager lean coal.
Shaanxi Province's Yulin City is the maximum blue charcoal production base of our province; Through new round structural adjustment; The blue charcoal industry in Yulin has realized garden layout, clustered production and recycle; But present industrial pattern more also rests on the gathering on the enterprise space, and promptly " enterprise clusters " but not " industry cluster " form complete relatively circulation industrial chain as yet in the garden; The coke-oven gas utilization also rests on simple fuel and utilizes, and fails to extend downstream, and industrial chain is shorter; Added value is lower; Enterprise is main with blue charcoal product still, and comprehensive benefit is not high, do not step into as yet " with Jiao base oneself upon, to change development " the benign development track; Cause blue charcoal energy consumption level and pollutant emission high thus, be faced with the immense pressure of energy-saving and emission-reduction.
About more than 5,000 ten thousand t of the total industrial scale of present domestic blue charcoal produce and mainly concentrate on areas such as northern Shensi, Inner Mongol, Ningxia, Xinjiang.The application market of blue charcoal is also mainly in central and west regions, like northwest, southwest, Central Plains and other places, the eastern region then since trucking costs than higher; The enterprise that uses is also less relatively; Have only Danjiang River, Hubei electrification group, minority enterprises such as the electrochemical group of the huge ability in Zhejiang, but it all only limits to experiment; The ratio that the spray of blue charcoal is added, performance etc. all do not have research, can not in industry, use.
Summary of the invention
In order to overcome the deficiency of above-mentioned prior art, the object of the present invention is to provide a kind of pulverized coal injection into blast furna technology of utilizing blue charcoal, with blue charcoal last reign of a dynasty for hard coal; Strengthened the dynamics of utilizing at blue charcoal end; Actively extend industrial chain, improved blue charcoal industry comprehensive benefit, accelerated blue charcoal technical equipment typing; Promote industrialization level, become the mission critical that promotes the Sustainable development of blue charcoal industry.
To achieve these goals, the technical scheme of the present invention's employing is:
Iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal, with blue charcoal, hard coal and the bituminous coal mixed according to mass ratio 20:10:70, in grinding machine, wears into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilizes bf coal injection system to jet to blast furnace.
Another kind of scheme of the present invention with blue charcoal and hard coal, the bituminous coal mixed according to mass ratio 30:10:60, is worn in grinding machine behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilizes bf coal injection system to jet to blast furnace.
Another kind of scheme of the present invention with blue charcoal and hard coal, the bituminous coal mixed according to mass ratio 20:10:70, is worn in grinding machine behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilizes bf coal injection system to jet first to blast furnace; Again with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 25:10:65, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the secondary winding-up to blast furnace; At last with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 30:10:60, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the last winding-up to blast furnace; The total mass of three winding-ups equates that injection rate equates.
Said grinding machine is the middling speed grinding machine.
Said blue charcoal is worn into particle diameter for to account for 85% powder less than 180 orders in grinding machine.
The explosivity of said blue charcoal is returned the length of flame less than 150mm; Hardgrove grindability index (HGI) is greater than 56; Point of ignition is 380 ℃.
Compared with prior art, advantage of the present invention is:
(1) will further expand the industrial application of blue charcoal, help accelerating industry development;
(2) the blue charcoal blast furnace blowing supply situation that can alleviate coking coal and be becoming tight hard coal day helps dry distillation of coal The Application of Technology and promotes;
(3) blue charcoal substitutes hard coal, meets the requirement of national current energy-saving and emission-reduction.Simultaneously, cheap blue charcoal price is with the economic benefit that significantly promotes down-stream enterprise.
Embodiment
Below in conjunction with embodiment the present invention is explained further details.
Embodiment one
Iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal, with blue charcoal, hard coal and the bituminous coal mixed according to mass ratio 20:10:70, in grinding machine, wears into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilizes bf coal injection system to jet to blast furnace.
Embodiment two
Iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal, with blue charcoal and hard coal, the bituminous coal mixed according to mass ratio 30:10:60, in grinding machine, wears into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilizes bf coal injection system to jet to blast furnace.
Embodiment three
Iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal, and blue charcoal is worn into particle diameter for to account for 85% powder less than 180 orders in the middling speed grinding machine.To grind good blue charcoal and hard coal, bituminous coal mixed then, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, and utilize bf coal injection system to jet first to blast furnace according to mass ratio 20:10:70; Again with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 25:10:65, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the secondary winding-up to blast furnace; At last with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 30:10:60, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the last winding-up to blast furnace; The total mass of three winding-ups equates that injection rate equates.
More than among three embodiment, the explosivity of said blue charcoal is returned the length of flame less than 150mm; Hardgrove grindability index (HGI) is greater than 56; Point of ignition is 380 ℃.
Further to the present invention program's analysis that makes an experiment:
1. blast furnace injection coal index request such as table 1:
Table 1 coal suitable for blowing index request
2 coal sources are selected
Reach the coal source such as the table 2 of coal suitable for blowing requirement:
Table 2 coal source situation
Above foam coal, 3# cleaned coal, blue charcoal foam, blue carbon granule are that one one in furnace charge provides new available coal source coal, and wherein blue carbon granule needs broken.
3. grindability index
Can know that by table 1 and table 2 coal that imperial steel provided and the ash oontent of blue charcoal all meet the coal suitable for blowing index request, moisture content is then all higher, so grindability index is generally lower, needs to improve with the method for coal blending.
4. explosive
Bituminous coal and anthracitic volatile matter are lower, so explosivity is more weak, and the volatile content of high-volatile bituminous coal is bigger, therefore have intense explosion property.The fugitive constituent of blue charcoal is lower, thus explosivity also very a little less than.
5. point of ignition
The high-volatile bituminous coal volatile content is bigger, so its point of ignition is lower.
According to above analysis, comprehensive coal cost performance can be selected the coal blending scheme like table 3, supposes that there are four new stoves in certain steel mill, an old stove.Table 4 is for substituting coal dust mixed coal price afterwards with blue charcoal foam.
Table 3 coal blending scheme
Table 4 substitutes coal dust mixed coal price afterwards with blue charcoal foam
Suppose 4,000,000 tons of certain steel mill's YO, coal is than 150Kg/t iron, and a year consumption of coal is 600,000 tons, if with after alternative 10% breeze blowing of blue foam, then can practice thrift 296.4 ten thousand yuan every year.If after alternative 20% breeze blowing of blue foam, the then annual expense that can practice thrift can be more.
Claims (6)
1. iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal; It is characterized in that; With blue charcoal, hard coal and bituminous coal mixed according to mass ratio 20:10:70, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to jet to blast furnace.
2. iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal; It is characterized in that; With blue charcoal and hard coal, bituminous coal mixed according to mass ratio 30:10:60, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to jet to blast furnace.
3. iron work utilizes the pulverized coal injection into blast furna technology of blue charcoal; It is characterized in that; With blue charcoal and hard coal, bituminous coal mixed according to mass ratio 20:10:70, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to jet first to blast furnace; Again with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 25:10:65, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the secondary winding-up to blast furnace; At last with blue charcoal and hard coal, bituminous coal mixed according to mass ratio 30:10:60, in grinding machine, wear into behind the powder under 1200 ℃ of conditions of wind-warm syndrome, utilize bf coal injection system to carry out the last winding-up to blast furnace; The total mass of three winding-ups equates that injection rate equates.
4. utilize the pulverized coal injection into blast furna technology of blue charcoal according to the described iron work of the arbitrary claim of claim 1 to 3, it is characterized in that said grinding machine is the middling speed grinding machine.
5. utilize the pulverized coal injection into blast furna technology of blue charcoal according to the described iron work of the arbitrary claim of claim 1 to 3, it is characterized in that said blue charcoal is worn into particle diameter for to account for 85% powder less than 180 orders in grinding machine.
6. utilize the pulverized coal injection into blast furna technology of blue charcoal according to the described iron work of the arbitrary claim of claim 1 to 3, it is characterized in that the explosivity of said blue charcoal is returned the length of flame less than 150mm; Hardgrove grindability index (HGI) is greater than 56; Point of ignition is 380 ℃.
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Cited By (11)
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CN103255247A (en) * | 2013-05-22 | 2013-08-21 | 南京钢铁股份有限公司 | Coal blending method for blast furnace coal injection |
CN104212508A (en) * | 2014-09-28 | 2014-12-17 | 四川德胜集团钒钛有限公司 | Blast furnace blowing mixed fuel and blowing method thereof |
CN105603180A (en) * | 2016-01-28 | 2016-05-25 | 西安建筑科技大学 | Method for producing sinter at low cost |
CN106011340A (en) * | 2016-08-08 | 2016-10-12 | 四川德胜集团钒钛有限公司 | Blending scheme of pulverized coal for blast furnace injection |
CN107574274A (en) * | 2017-09-29 | 2018-01-12 | 四川德胜集团钒钛有限公司 | A kind of blowing method of mixed fuel for blast furnace injection |
CN108531674A (en) * | 2018-05-04 | 2018-09-14 | 包头市国卉能源科技有限责任公司 | The method for preparing pulverized coal injection in blast furnace as blast furnace blowing raw material using semi-coke |
CN111961772A (en) * | 2020-08-19 | 2020-11-20 | 付光临 | Preparation method and application of modified semi coke |
CN112063781A (en) * | 2019-06-10 | 2020-12-11 | 上海梅山钢铁股份有限公司 | Coke powder-containing mixed fuel for blast furnace coal injection and preparation method thereof |
CN112143841A (en) * | 2020-09-21 | 2020-12-29 | 西安建筑科技大学 | System and method for blast furnace mixed blowing of semi coke |
CN114106900A (en) * | 2020-08-28 | 2022-03-01 | 上海梅山钢铁股份有限公司 | Semi-coke-containing mixed fuel for blast furnace injection and preparation method thereof |
CN114507553A (en) * | 2020-11-17 | 2022-05-17 | 上海梅山钢铁股份有限公司 | Mixed fuel with high coal-coke replacement ratio for blast furnace injection and preparation method thereof |
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CN103255247B (en) * | 2013-05-22 | 2015-08-26 | 南京钢铁股份有限公司 | A kind of blast furnace injection coal blending method |
CN103255247A (en) * | 2013-05-22 | 2013-08-21 | 南京钢铁股份有限公司 | Coal blending method for blast furnace coal injection |
CN104212508A (en) * | 2014-09-28 | 2014-12-17 | 四川德胜集团钒钛有限公司 | Blast furnace blowing mixed fuel and blowing method thereof |
CN105603180A (en) * | 2016-01-28 | 2016-05-25 | 西安建筑科技大学 | Method for producing sinter at low cost |
CN106011340B (en) * | 2016-08-08 | 2018-10-30 | 四川德胜集团钒钛有限公司 | A kind of coal blending component of pulverized coal injection into blast furna |
CN106011340A (en) * | 2016-08-08 | 2016-10-12 | 四川德胜集团钒钛有限公司 | Blending scheme of pulverized coal for blast furnace injection |
CN107574274A (en) * | 2017-09-29 | 2018-01-12 | 四川德胜集团钒钛有限公司 | A kind of blowing method of mixed fuel for blast furnace injection |
CN108531674A (en) * | 2018-05-04 | 2018-09-14 | 包头市国卉能源科技有限责任公司 | The method for preparing pulverized coal injection in blast furnace as blast furnace blowing raw material using semi-coke |
CN112063781A (en) * | 2019-06-10 | 2020-12-11 | 上海梅山钢铁股份有限公司 | Coke powder-containing mixed fuel for blast furnace coal injection and preparation method thereof |
CN111961772A (en) * | 2020-08-19 | 2020-11-20 | 付光临 | Preparation method and application of modified semi coke |
CN114106900A (en) * | 2020-08-28 | 2022-03-01 | 上海梅山钢铁股份有限公司 | Semi-coke-containing mixed fuel for blast furnace injection and preparation method thereof |
CN112143841A (en) * | 2020-09-21 | 2020-12-29 | 西安建筑科技大学 | System and method for blast furnace mixed blowing of semi coke |
CN114507553A (en) * | 2020-11-17 | 2022-05-17 | 上海梅山钢铁股份有限公司 | Mixed fuel with high coal-coke replacement ratio for blast furnace injection and preparation method thereof |
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