CN105274268A

CN105274268A - Mixed charging method for small-granularity agglomerate and coke nut

Info

Publication number: CN105274268A
Application number: CN201410256282.1A
Authority: CN
Inventors: 车玉满; 郭天永; 孙鹏; 姚硕; 陈国一
Original assignee: Angang Steel Co Ltd
Current assignee: Angang Steel Co Ltd
Priority date: 2014-06-11
Filing date: 2014-06-11
Publication date: 2016-01-27
Anticipated expiration: 2034-06-11
Also published as: CN105274268B

Abstract

The invention provides a mixed charging method for small-granularity agglomerate and coke nut. The method comprises performing once-more sieving on sintering return mines with the granularity less than 5 mm, and putting the return mines with the granularity larger than 3 mm into an assigned ore groove; putting a mixed furnace material of small-granularity agglomerate with the ratio by mass of 95%-97% and coke nut with the ratio by mass of 3%-5% into an assigned ore groove; controlling the batch weight of a mixed furnace material of 70%-75% by mass of agglomerate with normal granularity and 25%-30% by mass of pellet ore to be 58-62 t, and controlling the batch weight of the mixed furnace material of small-granularity agglomerate and coke nut to be 7-11 t; during charging, firstly executing the charging institution of 70%-75% by mass of agglomerate with normal granularity and 25%-30% by mass of pellet ore, then executing a normal coke charging institution, and distributing the mixed furnace material of small-granularity agglomerate and coke nut at the edge, and successively circularly charging the materials according to the above charging sequence. By utilizing coke nut, the small-granularity agglomerate breathability is improved and the small-granularity agglomerate recovery utilization amount is raised.

Description

A kind of small sinter and nut coke mixing loading method

Technical field

The invention belongs to blast furnace ironmaking field, be specifically related to reclaim small sinter and nut coke mixing loading method.

Background technology

In current SINTERING PRODUCTION technique, in finished product agglomerate, granularity is less than the 5mm ratio of returning mine and is approximately 10 ~ 15%, be 1,650 ten thousand t/a enterprises for year pig iron output, year needs agglomerate to be approximately 2,400 ten thousand t/a, generation is less than 5mm and returns mine 240 ~ 3,600,000 t/a, is equivalent to 145 ~ 218kg/t iron by pig iron Production rate quantity of return mines.At present, most enterprise is all less than 5mm using granularity and returns mine and return to sintering mill (plant) and again sinter as hearth layer for sintering, waste solid burnup and manufacturing cost, and return mine increases transportation cost with automobile or belt-conveying simultaneously between blast furnace ore tank and sinter machine.

Granularity be less than 5mm return mine in size composition be generally: >5mm ratio is 5%, 3 ~ 5mm ratio is 55%, <3mm ratio is 40%, wherein >3mm ratio is about 60%, quantity is about 144 ~ 2,160,000 t/a, if reclaim 3 ~ 5mm small sinter and improve Strand Feeding Technique, directly add blast furnace and substitute normal agglomerate, then significantly can reduce production cost.

But owing to returning mine granularity between 3 ~ 5mm, and normal agglomerate granularity is between 5 ~ 40mm, and wherein 10 ~ 40mm ratio is greatly about 80%, returns mine huge with normal agglomerate size composition gap.Therefore, can 3 ~ 5mm small sinter enter stove and utilize, and depends on that can blast furnace accept, if small sinter usage quantity is too much or distributing mode is inappropriate, all can affects furnace charge air permeability, thus affect smooth operation of furnace.

Domestic at present only have several the enterprises such as Ma'an Mountain, the granule part of 3 ~ 5mm in BF return fines is reclaimed back into stove by screening, burden distribution system is cloth 1 small sinter after the subnormal material of every cloth 4 ~ 5, and batch weight is reduced to normal furnace charge batch weight 2 ~ 4%, below 27kg/t iron, huge spread is there is compared with 145 ~ 218kg/t iron quantity of return mines in consumption according to furnace condition anterograde condition basic controlling.

Number of patent application 201010144395.4 (central cooler distributing process and device) announces a kind of sintering circular-cooler distributing process, it is point three layers of laying agglomerate on circular cooler trolley, bottom is based on volume particle size agglomerate, middle level is based on small sinter, top layer is based on medium size agglomerate, favourable recycling small sinter, this patent does not still solve small sinter and is directly recovered into stove and substitutes normal agglomerate problem.

Document " horse steel 2500m ³blast furnace small sinter is recycled " author: Ding Hui, Li Bangping " ironmaking " 2 phases in 2002, introduce horse steel 2500m ³blast furnace small sinter quantity of return mines reaches 280kg/t iron, quantity of return mines is huge, if all return sinter machine production cost significantly to increase, the small sinter of recovery part 3 ~ 5mm, after 7 ~ 9 subnormal material, cloth 1 small sinter, small sinter recycling amount 26.5kg/t iron.

Document " Ji steel No. 1 blast furnace small sinter enter stove technological development and application " author: Li Chuanhui, pacify and engrave " iron and steel " 12 phases in 2007, introduce the small sinter of recovery part 3 ~ 5mm, after 6 ~ 15 subnormal material, cloth 1 small sinter, and cloth is at edge.

Document " recycling of climbing the new three blast furnace small sinters of steel is put into practice " author: Lin Chuan " Sichuan is metallurgical " 6 phases in 2011, introduce the small sinter of recovery part 3 ~ 5mm, after the subnormal material of cloth 8, cloth 1 small sinter.

Above-mentioned document Shortcomings is, because small sinter and normal agglomerate particle size differences are large, easily causes that stock column voidage in stove declines, ventilation property is deteriorated, and has a negative impact to smooth operation of furnace, recycles small sinter amount few.

Summary of the invention

For overcoming the shortcomings such as yield existing for existing recycling small sinter is few, benefit is low, change current nut coke and normal agglomerate charging method, small sinter and nut coke being loaded in mixture one specifies in the groove of ore deposit, nut coke is fully mixed with small sinter, nut coke is utilized to improve mixture charge ventilation property, after mixing, furnace charge enters stove as normal furnace charge, substitutes normal segments agglomerate, improves small sinter recycling amount.

(1) under agglomerate groove, setting up 3mm specification strip-type screen, again sieving being less than 5mm sinter return fine, sift out and be greater than 3mm and return mine to load and specify in ore deposit groove;

(2) proportioning be 95% ~ 97% small sinter, proportioning is that 3% ~ 5% nut coke mixture charge loads and specifies ore deposit groove;

(3) 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% pellet mixture charge batch weight are 58 ~ 62t, and small sinter and nut coke mixture charge batch weight are 7 ~ 11t;

(4) blast furnace adopts following burden distribution system at charging process, first 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% pellet burden distribution system is performed, then normal coke burden distribution system is performed, finally perform small sinter and nut coke mixture charge, small sinter and nut coke mixture charge cloth at edge, then by above-mentioned cloth order circulating burden distribution successively;

Per-cent involved in above step is mass percent.

Proportioning is 95% ~ 97% small sinter, proportioning is 3% ~ 5% nut coke mixture charge, be by using mixture charge voidage testing apparatus, the voidage of test 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% pellet mixture charge is 0.40 ~ 0.45 to determine.Use same mixture charge voidage testing apparatus, test is with addition of different mass mark nut coke and small sinter mixture charge voidage, when voidage reaches 0.40 ~ 0.45, be consistent with 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% pellet voidage, permeability of stock column in blast furnace is avoided to change, now nut coke proportioning is 3% ~ 5%, and small sinter proportioning is 95% ~ 97%.

The present invention has following characteristics and beneficial effect:

(1) 100% ground recycle be less than 5mm return mine in 3 ~ 5mm small sinter, directly add the normal agglomerate of blast furnace Substitute For Partial, considerably reduce production cost.

(2) load in mixture with nut coke and small sinter, play the large feature of small sinter specific surface, increase Gas Flow and ore layer Exposure, improve the ventilation property of blast furnace, improve gas utilization rate.

Embodiment

Below in conjunction with specific embodiment, the present invention is described in further detail, but become any limitation of the invention not, and per-cent involved in embodiment is mass percent.

Embodiment one:

(1) under agglomerate groove, setting up 3mm specification strip-type screen, again sieving being less than 5mm sinter return fine, sift out and be greater than 3mm and return mine;

(2) proportioning be 95% small sinter, proportioning is 5% nut coke mixing, load and specify ore deposit groove;

(3) small sinter and nut coke mixture charge batch weight is selected to be 7t;

(4) 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% Furnace Pellet charge is selected to be heavily 58t;

(5) blast furnace adopts following burden distribution system at charging process, first normal furnace charge burden distribution system is performed, then normal coke burden distribution system is performed, small sinter and nut coke mixture charge perform outermost monocycle burden distribution system, small sinter and nut coke mixture charge cloth at edge, then by above-mentioned cloth order circulating burden distribution successively.

Embodiment two:

(2) proportioning be 97% small sinter, proportioning is 3% nut coke mixing, load and specify ore deposit groove;

(3) small sinter and nut coke mixture charge batch weight is selected to be 11t;

(4) 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% Furnace Pellet charge is selected to be heavily 62t;

Embodiment three:

(2) proportioning be 96% small sinter, proportioning is 4% nut coke mixing, load and specify ore deposit groove;

(3) small sinter and nut coke mixture charge batch weight is selected to be 9t;

(4) 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% Furnace Pellet charge is selected to be heavily 60t;

Claims

1. small sinter and a nut coke mixing loading method, is characterized in that comprising the following steps:

Per-cent involved in above step is mass percent.

2. a kind of small sinter according to claim 1 and nut coke mixing loading method, is characterized in that proportioning is 95% ~ 97% small sinter, proportioning is 3% ~ 5% nut coke mixture charge voidage and 70% ~ 75% normal particle sizes agglomerate+25% ~ 30% pellet mixture charge voidage is 0.40 ~ 0.45.