A kind of controlling reduces the method that lateritic nickel ore produces high-quality ferronickel
Technical field
The present invention relates to the production method of ferronickel, more particularly to a kind of controlling reduction lateritic nickel ore production high-quality nickel
The method of ferrum.
Background technology
Nickel, as main alloy element, is applied to rustless steel, heat-resisting alloy steel and multiple nickel alloy, accounts for nickel total amount consumed
More than 70%.With the fast development of rustless steel industry, the demand of nickel is also significantly increased.At present, global mine nickel yield
60% derives from nickel sulfide ore, and 40% derives from lateritic nickel ore.And in 2.2 hundred million tons of global nickel minerals reserves, lateritic nickel ore accounts for
70%.Continuous minimizing with nickel sulfide ore resource and the continuous progress of smelting laterite-nickel ores technology, produce nickel from lateritic nickel ore
Proportion will be continuously increased.
For the existing following different disposal technique of different types of lateritic nickel ore: thermal process, wet processing, fiery wet method knot
Close technique and other techniques.Wherein thermal process, because flow process is short, efficiency high, the advantages for the treatment of scale is big, is to process laterite
The leading technology of nickel minerals.In lateritic nickel ore pyrogenic attack technique, blast furnace process and electric furnace smelting are conventional process flow, wherein
Although blast furnace process production capacity is big, investment is high, production cost is high, and more than the 80% of electric furnace smelting energy consumption has electric energy to provide,
High energy consumption.And the relative density ratio of nickel is larger, is easily deposited on furnace bottom, furnace wall and furnace bottom is caused to be etched or burn.This
Outward, the maximum shortcoming of both the above technique is that ferronickel carbon content is high, produces to rustless steel and causes very big difficulty.
Based on the shortcoming of above pyrometallurgical smelting, metallurgical researcher develops the technique of non-traditional flow process, including revolution
Kiln method and rotary hearth furnace method.Although kiln process invests little, process is simple, production capacity is low, and floor space is big, and automaticity is not
High.And the investment of rotary hearth furnace method is big, production capacity is low, complex process.
In sum, for the ore deposit phase feature of lateritic nickel ore and the shortcoming of existing process, develop at rational lateritic nickel ore
Science and engineering skill, becomes ferronickel and produces extremely urgent demand.
The application publication number of Chinese patent is cn 101935794 a, and a kind of entitled lateritic nickel ore melts a point stove in shaft furnace
The middle method producing dilval, its technical scheme is: carbon containing made by lateritic nickel ore powder and reducing agent (coal dust, coke powder or semicoke)
Pelletizing, then at a temperature of 800~1250 DEG C in shaft furnace, reductase 12~8h, the pelletizing pulverizing and jevigating after reduction, magnetic separation obtain
Ferronickel concentrate, then concentrate is mixed compacting balling-up with additive, 1450~1550 DEG C in molten point of stove at a temperature of, through 20~
60min melting obtains dilval.The method technology maturation, simple to operate, easy control of process conditions.The method has as follows
Shortcoming:
(1) the method adopts coal base reduction method, that is, be used coal dust, coke powder or semicoke as reducing agent it is impossible to realize regulation and control
The reducing degree of nickel and ferrum in reduction process, thus control the nickel content in dilval;
(2) carbonaceous reducing agent is conducive to carburizing, leads to carbon content in ferronickel higher, is unfavorable for stainless steel smelting;
(3) harmful element such as s, p containing in carbonaceous reducing agent can enter product dilval, reduces the quality of ferronickel;
(4) reduction shaft furnace temperature is at 1000 DEG C about, and molten point of temperature, at 1500 DEG C about, leads to the energy consumption of whole operation
Relatively higher;
(5) during molten point, the furnace wall of molten point of stove and furnace bottom are easily etched or burn.
The application publication number of Chinese patent is cn 101603110 a, entitled direct for raw material shaft furnace with lateritic nickel ore
The method of reduction ferronickel, its technical scheme is: lateritic nickel ore and reducing agent (coal dust or coke powder) load shaft furnace, in proportion 700
Pre-heating drying 2~4h at a temperature of~900 DEG C, heats reduction 4~8h at a temperature of 900~1300 DEG C, then through broken, ball
Mill, magnetic separation, briquetting, obtain qualified direct-reduction ferronickel.The method investment is little, production capacity is high, process stabilizing, simple to operate, machine
Tool degree is high, operating cost is low.The reducing agent that the method uses is still carbonaceous reducing agent, uncontrollable in reduction process
The reducing degree of nickel and ferrum is it is impossible to regulate and control the content of nickel in dilval.And carbonaceous reducing agent lead in dilval s, p and
Carbon content increases, and reduces the quality of product ferronickel.
The application publication number of Chinese patent is cn 101845530 a, and entitled laterite fluid bed produces dilval
Technique, its technical scheme is: after laterite drying, broken, screening, yields less than the laterite breeze of 3mm, then in fluid bed
In roaster, it is preheating to 700~950 DEG C, in reduction fluid bed, reduce 30~100min at a temperature of 650~900 DEG C,
Again through broken, physical separation, obtain qualified direct-reduction ferronickel.The method is strong to adaptability to raw material, saves pelletizing operation, instead
Answer temperature low, energy consumption is low, dilval product quality is high, and can in flexible dilval nickel content.The method just has
Following shortcoming:
(1) the method, in reduction process, due to the appearance of metallic iron, leads to the generation of bonding defluidization in fluid bed.
Especially in reduction fluid bed, when temperature reaches 900 DEG C, leakage is than more serious.It is necessary to stop production after defluidization occurs
Cleaning, thus cannot continuous operation, affect whole technique production capacity;
(2) in fluid bed, because powder occurs different degrees of back-mixing, lead to that powder stops in fluid bed when
Between different, therefore reducing degree is different, thus the ferronickel quality producing is uneven.
Content of the invention
It is an object of the invention to provide a kind of controlling reduces the method that lateritic nickel ore produces high-quality ferronickel, existing to solve
With the presence of Proress Technolgies of Laterite-nickel Ore produce ferronickel method cannot regulate and control nickel content in dilval, carbon content in dilval
And s, p content is high, technique productions high energy consumption, operate the problems such as serialization is poor, and ferronickel quality is uneven.
The purpose of the present invention is achieved through the following technical solutions:
A kind of controlling reduces the method that lateritic nickel ore produces high-quality ferronickel, comprises the steps:
(1) ore is carried out gas drying;
(2) ore after drying carries out crushing, sieves;
(3) mineral dust after sieving enters and carries out prereduction through reducing gas in fluidized bed;
(4) the mineral dust hot wafering after prereduction;
(5) Ore after briquetting enters shaft furnace and is reduced through reducing gas;
(6) Ore after reduction treatment carry out crushing, levigate and carry out physical separation and obtain high-quality dilval;
The gas of described step (1) comes from fluid bed furnace top gas in step (3);In described step (3), fluid bed is many
Level fluid bed, reducing gas comes from shaft furnace top gas in step (5);In described step (3) and (5), reducing gas is coal system
One or more of gas, converting coke oven gas gas and gas renormalizing gas.
Preferably, described reducing gas enters through desulfurization and decarburization and enters reduction shaft furnace mineral powder after gas heating stove heating
End.
Preferably, the ore in described step (1) is lateritic nickel ore, and wherein nickel grade is 0.5%~3%, ferrum product
Position 10%~50%.
Preferably, the gas temperature in described step (1) is 100~150 DEG C, and ore is dried to breeze moisture
Less than 5%.
Preferably, the lateritic nickel ore in described step (2) is broken to less than 3mm, screens out the lateritic nickel ore of 0.01~3mm
Powder.
Preferably, in described step (3), multistage fluidized bed is 2-4 level, and the temperature of reducing gas is 400~650 DEG C, gas
Middle co+h2>=55%, pre-reduction time is 60~120min, and in multistage fluidized bed, pressure is 0.1~0.4mpa.
Preferably, the reducing gas temperature in described step (5) is 700~900 DEG C, co+h in gas2>=70%, reduction
Time is 30~60min, and perpendicular furnace pressure is 0.4~1.0mpa.
Preferably, the metallization lateritic nickel ore in described step (6) discharged shaft furnace crushes, levigate to less than 74 μm, warp
Physical separation obtains nickel grade and is more than 10%, p < 0.035%, the high-quality dilval of s < 0.030%, c < 1.0%.
Preferably, described physical separation includes magnetic separation, flotation or gravity treatment.
Preferably, the scrubbed dedusting of gas after drying in described step (1) and reducing gas carry out mixing Posterior circle to be made
With.
Beneficial effects of the present invention:
(1) reducing agent of the present invention is gaseous reducing agent, can be from coal gas, converting coke oven gas gas or natural gas weight
Whole gas, gas raw material is in extensive range, and has essence different from solid carbonaceous reducing agent.Except by control reduction temperature and
Recovery time, realize outside the reducing degree of ferrum and nickel in regulation and control lateritic nickel ore, co+h in Primordial Qi can also be gone back by controlling2Ratio
Example, the reducing degree of ferrum and nickel in regulation and control lateritic nickel ore, the real content realizing nickel in control product dilval.Therefore this
Bright spendable lateritic nickel ore is in extensive range, and nickel grade is 0.5%~3%, and the resource of Iron grade 10%~50% is all applicable.
(2) gaseous reducing agent of present invention employing cleaning, p < 0.035% in the dilval of production, s < 0.030%,
And by controlling co+h in reducing gas2Ratio, c < 1.0% in controllable dilval.
(3) present invention adopts the technique of fluid bed prereduction+reduction shaft furnace, inhomogenous for reducing degree in fluid bed
Breeze, can reach uniform reducing degree it is ensured that all product high-quality of the method and uniformity after reduction shaft furnace.
(4) present invention adopts multistage fluidized bed as prereduction device, because in fluid bed, temperature is lower, and reducing gas
Middle co+h2Ratio also ratio is relatively low, the metallic iron restoring in breeze is not only few, and the defluidization that bonds will not occur, thus protecting
Demonstrate,prove the operation serialization of whole technological process.
(5) reduction temperature of the present invention is less than 900 DEG C, is increased to more than 1500 DEG C without by temperature of charge, makes whole work
The energy consumption of skill flow process is greatly reduced.
(6) present invention adopts fluid bed prereduction, not only takes full advantage of fluid-bed heat transfer efficiency high, response speed fast
Feature, and save pressure ball or pelletizing and the operation of follow-up agglomerates, both shorten technological process, reduce energy consumption again.
Brief description
Fig. 1 is that a kind of controlling of the present invention reduces the method flow diagram that lateritic nickel ore produces high-quality ferronickel;
Specific embodiment
In order to the present invention is better described, with reference to the accompanying drawing in the embodiment of the present invention, in the embodiment of the present invention
Technical scheme is clearly and completely described.
As illustrated, a kind of controlling reduces the method that lateritic nickel ore produces high-quality ferronickel, comprise the steps:
(1) lateritic nickel ore raw material is carried out gas drying;
(2) the lateritic nickel ore raw material after drying carries out crushing, sieves;
(3) the lateritic nickel ore powder after sieving enters and carries out prereduction through reducing gas in fluidized bed;
(4) the lateritic nickel ore powder hot-pressing block after prereduction;
(5) lateritic nickel ore after briquetting enters shaft furnace and is reduced through reducing gas;
(6) lateritic nickel ore after reduction treatment carry out crushing, levigate and carry out physical separation and obtain high-quality dilval;
Described lateritic nickel ore, wherein nickel grade are 0.5%~3%, Iron grade 10%~50%.The ore resource scope of application
Extensively.Described reducing gas is one or more of coal gas, converting coke oven gas gas and gas renormalizing gas.Using gas also
Former dose, nickel content in real realization regulation and control product dilval, and reduce the content of s, p, c in dilval, be conducive to not
Rust steel smelting.
Reducing gas enters gas heating stove after desulfurization and decarburization and is heated, subsequently into shaft furnace, by vertical furnace top row
Go out laggard fluidized bed, be used for drying lateritic nickel ore by fluid bed expellant gas, then scrubbed dedusting, then go back with fresh
Raw-gas mix.Reducing gas composition can realize regulation and control by reducing gas preparation section and gas decarbonization process.By vertical furnace
Top gas is used for fluid bed reduction, and fluid bed furnace top gas is used for lateritic nickel ore dries.Reducing gas one-time heating to 700~
900 DEG C, this had both taken full advantage of the heat of gas, has been improved the reduction utilization rate of gas, has significantly reduced whole technique
Energy consumption.
Gas temperature in described step (1) is 100~150 DEG C, and lateritic nickel ore raw material stoving is little to breeze moisture
In 5%.
Lateritic nickel ore in described step (2) is broken to less than 3mm, screens out the lateritic nickel ore powder of 0.01~3mm.
Multistage fluidized bed, preferably 2-4 level fluid bed in described step (3), the temperature of reducing gas is 400~650 DEG C, gas
Co+h in body2>=55%, pre-reduction time is 60~120min, and in multistage fluidized bed, pressure is 0.1~0.4mpa.Described step
(5) in, reducing gas temperature is 700~900 DEG C, co+h in gas2>=70%, the recovery time is 30~60min, and shaft furnace is intrinsic pressure
Power is 0.4~1.0mpa.Using the technique of fluid bed prereduction+reduction shaft furnace, make use of fluid-bed heat transfer efficiency high, reaction speed
Spend fast feature, turn avoid the appearance of bonding defluidization problem, shaft furnace can also ensure that product quality is homogeneous simultaneously.In addition save
The operation of pressure ball or pelletizing and follow-up agglomerates, had both shortened technological process, had reduced energy consumption again.
The metallization lateritic nickel ore in described step (6) discharged shaft furnace crushes, levigate to less than 74 μm, through physical separation
Obtain nickel grade and be more than 10%, p < 0.035%, the high-quality dilval of s < 0.030%, c < 1.0%, this product can
It is directly used in stainless steel smelting it is also possible to preserving after briquetting or transporting for long-distance.Described physical separation includes magnetic separation, flotation or weight
Choosing.
Reducing gas of the present invention can be from coal gas, converting coke oven gas gas or gas renormalizing gas, in lateritic nickel ore
Nickel grade is 0.5%~3%, Iron grade 10%~50%, and gas raw material and ore scope are wide.
The above, the only present invention preferably specific embodiment, but protection scope of the present invention is not limited thereto,
Any those familiar with the art in the technical scope of present disclosure, the change or replacement that can readily occur in,
All should be included within the scope of the present invention.Therefore, protection scope of the present invention should be with the protection of claims
Scope is defined.