CN1029629C

CN1029629C - Small-ball sintering mine making method of all-magnet concentrate

Info

Publication number: CN1029629C
Application number: CN 93101629
Authority: CN
Inventors: 单继国; 刘淑桂
Original assignee: Central Iron and Steel Research Institute
Current assignee: Central Iron and Steel Research Institute
Priority date: 1993-02-18
Filing date: 1993-02-18
Publication date: 1995-08-30
Anticipated expiration: 2013-02-18
Also published as: CN1074713A

Abstract

The present invention relates to a making method for a small-ball sintering mine of all-magnet concentrates. In the method, all-magnet concentrates, a fluxing agent, return mines, slaked lime and a small amount of solid fuel are mixed by adding water so as to make small balls with the size of 3.15 to 12.5mm, and then, the small balls and the solid fuel are sintered by an ordinary sintering method after being mixed. In the method, material beds do not need to be dried before ignition and the basicity of sintering mines can be adjusted according to the requirements for blast furnaces because of no special requirements for the particle size of sintering crude fuel. Therefore, the method has the advantages of wide application range and easy popularization.

Description

Small-ball sintering mine making method of all-magnet concentrate

The invention belongs to the manufacturing field of iron-smelting raw material agglomerate.Be specially adapted to the manufacture method of all-magnet concentrate small-ball sintering mine.

Known from institute, under the same conditions, the output of sinter machine is along with the dosage of iron ore concentrate in the sinter mixture increases and reduces.For a large amount of output of using iron ore concentrate and don't reducing sinter machine, at present, domestic and international many manufacturers all research and develop.For example, the manufacture method (CN87108122A) of the pellet agglomerate introduced of NKK Corp.It is that fusing assistant and particle are rolled the coke powder of particle diameter for≤1mm outside the green pellets surface for≤0.125mm fine iron ore is mixed and made into, to have the outer green pellets cloth that rolls coke powder then to sinter machine, sinter the pellet agglomerate that can satisfy the blast furnace requirement into by dry, igniting.Chinese patent (CN1074107A) has also been introduced a kind of manufacture method of ball agglomerate in addition.This method is with thin fine ore, rich ore powder, cold and hotly return mine, unslaked lime, Wingdale and additive and part coal charge are mixed and made into green pellets; And outside the green pellets surface, rolling the coal dust of one deck particle diameter for≤1mm, the raw pellet ore cloth that will have outer roll coal then sinters the ball agglomerate that can reach the blast furnace requirement into by dry, igniting again to sinter machine.The weak point of above-mentioned two kinds of methods is that solid imitation frosted glass (coke powder or coal dust) all need process into about 1mm powder.Before ignition of sintering process, the green pellets dryer section that accounts for sintering area 10%-15% all will be set, therefore above-mentioned manufacture method has shortcomings such as the high and product production of production cost is low.

The purpose of this invention is to provide a kind of is the manufacture method of the small-ball sintering mine of magnet fine mineral powder all, adopts this method to have characteristics such as productivity height, good product quality and solid burnup are low.

Main technical schemes of the present invention is with all-magnet concentrate, solvent, return mine, slaked lime and a small amount of coal dust add water again and be mixed and made into the bead that requires size, and then, adopt the down draft sintering legal system that does not add dryer section to produce small-ball sintering mine again with after bead and the coal dust mixing.The technical process of magnetite concentrate small-ball sintering mine making method proposed by the invention is as follows: the mixing → cloth of get the raw materials ready → prepare burden → mix → make ball → bead and coal dust → igniting sintering → fragmentation → heat sieve → cooling → cold sieve → finished product small-ball sintering mine.

1, get the raw materials ready: the granularity requirements to all-magnet concentrate is 0.08mm, should account for the 40-90% in this ore deposit.Flux is limestone powder or ground dolomite, and its granularity requirements should account for more than 90% of this flux less than 3.15mm.Return mine and return mine or hot returning ore for cold, its granularity requirements should account for more than 90% of return fines material less than 5mm's.Binding agent is a slaked lime, and its granularity requirements＜3.15mm should account for more than 95% of this material.Solid fuel is coal dust or coke powder, granularity requirements should＜5mm wherein should account for more than 90% of this material less than 3mm.

2, batching: batching should be adjusted the amount of allocating into of flux according to the desired basicity of blast furnace.The amount of allocating into of its concrete each raw material should be (weight %) flux 1-15%, returns mine 15～20%, slaked lime 3-8%, and solid fuel 0.4～0.6%, all the other are the all-magnet concentrate powder.

3, mix: at first will prepare in the raw material input drum mixer of composition and carry out uniform mixing, and must add an amount of water simultaneously at blended.Moisture controlled is between 5～6%.

4, make bead:, when making ball, should add 7～9% water with making bead in the input of the compound behind the mixing pelletizer.Control the particle diameter and the output of bead by inclination angle, rotating speed and the blanking amount etc. of regulating pelletizer.To the particle diameter of mini-pellets require be 3.15～12.5mm should account for 80～95% of ball total amount.

5, bead mixes with solid fuel: will mix in bead and the solid fuel input drum mixer, the solid fuel add-on should be 1.5～4% of bead gross weight.The coal dust amount and the mixed homogeneity that stick to the green-ball surface are to be controlled by rotating speed, time and the inclination angle of adjusting mixing machine.

6, cloth: cloth should adopt wide conveyor to add the reflector distributor, and the sinter bed height is answered 〉=500mm.

7, igniting sintering: the inventive method is with the bead cloth sintering of can directly lighting a fire to the chassis.Ignition temperature should be 1050 ℃～1200 ℃, and 1～3 minute ignition time, the igniting negative pressure is 4000～6000Pa, and the sintering negative pressure is 5000～10000Pa.

8, fragmentation, hot sieve, cooling, cold sieve and finished product small-ball sintering mine: adopt shearing single roll crusher that small-ball sintering mine is crushed to below the 150mm, the reusable heat sieve sieves small-ball sintering mine, and sieve aperture is 4.5～5mm.Heat screening back small-ball sintering mine should be cooled to carry out cold screening below 150 ℃ again, in the thing that sifts＞5mm should be less than 10%, and screen overflow is the finished product-small-ball sintering mine, this product can directly be delivered to the blast furnace raw material storehouse, as the iron-smelting raw material of blast furnace.

Adopt the inventive method to produce small-ball sintering mine and have following characteristics compared with prior art.The inventive method technology is simple, need not reprocess raw materials for sintering, and solid imitation frosted glass granularity all adopts ordinary sinter granularity that method requires.The bead cloth is the direct ignition sintering on sinter machine, does not establish dryer section.Therefore the investment of the inventive method escapable cost and building equipment, and increased effective sintering area more than 10%.Characteristics such as this method has the productivity height, and solid burnup is low, every technical indicator all is better than prior art.

Embodiment

Adopt the inventive method, we have prepared three batches of all-magnet concentrate small-ball sintering mines, are described below the raw material granularity of table 1 embodiment according to tabulating down.The bead characteristic of the proportioning raw materials of table 2 embodiment (weight %) table 3 embodiment.In table 3, fall intensity and be meant that bead drops down onto on the thick copper coin of 20mm and broken number of times from the 0.5m eminence.The comparison of the processing parameter of table 4 embodiment and technical indicator and prior art.(table 1,2,3,4 is seen the literary composition back)

Table 1 embodiment raw material granularity

Lot number

Granularity (%) 123

All-magnet concentrate＜0.08%mm 44.10 40.5 42.30

Limestone powder＜3.15mm 81.60 80.50 82.14

Slaked lime＜3.15mm 96.00 95.80 95.70

Return fines material＜5mm 98.32 96.43 96.30

Solid fuel (coal dust)＜3.15mm 92.79 90.00 99.90

Table 2 embodiment proportioning raw materials (weight %)

Lot number

Raw material 123

All-magnet concentrate 63.57 65.80 69.78

Limestone powder 11.74 9.70 2.22

Slaked lime 4.02 4.50 6.00

Return mine 17.60 16.00 18.00

Basicity CaO/SiO ₂1.19 1.18 0.60

Solid fuel bead interior 0.5 0.5 0.5

(coal dust) bead outer 3.11 3.5 3.5

Table 3 embodiment bead performance

The bead granularity

Performance bead moisture content dropping strength

3.15～12.5mm

Lot number % % time

1 89.95 8.10 6.05

2 80.44 7.35 6.08

3 92.78 7.77 7.00

Table 4 embodiment processing parameter and technical indicator are compared with the prior art

Lot number emphasis iron and steel enterprise

1 2 3

Project＜1991 〉

Ignition temperature ℃ 1,100 1,050 1,150 1067

Sintering negative pressure Pa 6,500 6,300 6,000 10719

Bed depth mm 500 500 500 420

Utilization coefficient T/M ²H 1.93 1.81 1.61 1.34

ISO rotary drum＞6.3mm% 70.39 66.19 70.30/

Burnup Kg marks coal/ton 40.77 45.83 43.48 57.21

FeO% 9.52 9.98 12.70 10.20

Reduction degree %/77.6 64.70/

RDI（＜3mm）% / 35.22 17.65 /

Claims

1, a kind of manufacture method of all-magnet concentrate small-ball sintering mine is with all-magnet concentrate, flux, return mine, the solid fuel of slaked lime and required amount adds makes mini-pellets after water mixes, the composition that it is characterized in that raw material is to adopt the granularity of all-magnet concentrate should account for 40～90% of this ore deposit less than 0.08mm, the flux granularity is for should account for more than 90% of this flux less than 3.15mm, the granularity requirements of slaked lime should account for more than 95% of this material less than 3.15mm's, the return fines material granularity requirements should account for more than 90% of this return fines material less than 5mm, the solid fuel granularity requirements should be less than 5mm, wherein granularity should account for less than 3mm that this is solid-fuelled more than 90%, the particle diameter of the mini-pellets of making require for 3.15mm～12.5mm should account for 80～95% of mini-pellets total amount, adopt the down draft sintering legal system that does not add dryer section to produce small-ball sintering mine again after then whole mini-pellets and the solid fuel that accounts for this bead total amount 1.5～4% being mixed.

2, according to the manufacture method of the described small-ball sintering mine of claim 1, the ignition temperature that it is characterized in that adopting the down draft sintering that does not add dryer section is 1050～1200 ℃, the igniting negative pressure is 4000Pa～6000pA, and be 1～3 minute ignition time, and the sintering negative pressure is 5000Pa～10000Pa.