阅读说明：本技术 一种矿热炉低配铁、低硅镁比炉料及生产工艺 (Low iron-distribution and low silicon-magnesium ratio furnace charge for submerged arc furnace and production process ) 是由 杨超源 何丛珍 刘光勇 梁国燊 李健 陈海涛 吴杰阳 于 2019-12-19 设计创作，主要内容包括：本发明提供了一种矿热炉低配铁、低硅镁比炉料及生产工艺,属于矿热炉冶炼技术领域,并由不同品位的红土镍矿干矿、焦丁和煤粉根据以下成分的重量百分比配备而成：NiO 2.0-2.4％,Fe<Sub>2</Sub>O<Sub>3</Sub> 26.0-29.6％,SiO<Sub>2</Sub> 31.50-34.5％,MgO 19.0-21.5％,CaO 0.28-0.5％,Al<Sub>2</Sub>O<Sub>3</Sub> 2.06-4.03％,P 0.002-0.006％,S 0.025-0.055％,Cr<Sub>2</Sub>O<Sub>3</Sub> 1.9-2.35％,余下为其他微量元素；并通过对红土镍矿进行破碎筛分、干燥、配备炉料、焙烧预还原和还原熔炼得到含镍铁水。本发明通过采用该炉料结构进行生产,可以显著降低生产成本,并提高耐材寿命；同时采用该工艺可以提高整体回转窑的作业率,解决窜火冒烟的环保问题,以及炉盖坍塌的安全问题,实现矿热炉持续高效、稳定、安全的运行。(The invention provides a low-iron-distribution and low-silicon-magnesium-ratio furnace charge of an ore-smelting furnace and a production process, which belong to the technical field of ore-smelting furnace smelting, and are prepared from laterite-nickel ore dry ores of different grades, coke breeze and coal powder according to the following components in percentage by weight: NiO 2.0-2.4%, Fe 2 O 3 26.0‑29.6％，SiO 2 31.50‑34.5％，MgO 19.0‑21.5％，CaO 0.28‑0.5％，Al 2 O 3 2.06‑4.03％，P 0.002‑0.006％，S 0.025‑0.055％，Cr 2 O 3 1.9-2.35%, the rest is other microelements; and the nickeliferous laterite ore is crushed, screened, dried, prepared with furnace charge, roasted, pre-reduced and reduced to obtain nickeliferous molten iron. The furnace burden structure is adopted for production, so that the production cost can be obviously reduced, and the service life of refractory materials is prolonged; meanwhile, the process can improve the operation rate of the whole rotary kiln, solve the environmental protection problem of fire blow-by and smoke emission, and further realize the purpose of improving the working efficiency of the whole rotary kilnAnd the furnace cover collapses, thereby realizing the continuous, efficient, stable and safe operation of the submerged arc furnace.)

1. The utility model provides a hot stove in ore deposit low join in marriage iron, low silicon magnesium ratio furnace charge, includes laterite-nickel ore dry ore, coke breeze and buggy, its characterized in that: the laterite-nickel ore dry ore, the coke breeze and the coal powder with different grades are prepared according to the following components by weight percent:

NiO 2.0-2.4％，Fe₂O₃26.0-29.6％，SiO₂31.50-34.5％，MgO 19.0-21.5％，CaO0.28-0.5％，Al₂O₃2.06-4.03％，P 0.002-0.006％，S 0.025-0.055％，Cr₂O₃1.9-2.35%, and the balance of other trace elements.

2. The furnace burden with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace as claimed in claim 1, wherein: the paint is prepared from the following components in percentage by weight:

NiO 2.0-2.2％，Fe₂O₃26.0-27.5％，SiO₂33.5-34.5％，MgO 20.6-21.5％，CaO 0.3-0.4％，Al₂O₃3.0-3.8％，P 0.004-0.006％，S 0.035-0.045％，Cr₂O₃1.9-2.19%, and the balance of other trace elements.

3. The furnace burden with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace as claimed in claim 2, wherein: the paint is prepared from the following components in percentage by weight:

NiO 2.04％，Fe₂O₃26.43％，SiO₂34.32％，MgO 21.36％，CaO 0.35％，Al₂O₃3.27％，P0.005％，S 0.04％，Cr₂O₃1.93%, and the rest is other trace elements.

4. The furnace burden with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace as claimed in claim 1, wherein: the mass ratio of Fe to Ni in the furnace burden components is 11.82-12.96; the mass ratio of Si to Mg in the furnace burden components is 1.53-1.69.

5. The furnace burden with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace as defined in claim 4, wherein: the mass ratio of Fe to Ni in the furnace burden components is 12.96; the mass ratio of Si to Mg in the furnace burden components is 1.6.

6. The furnace burden with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace as claimed in claim 1, wherein: the alkalinity of the components is 0.61-0.66.

7. The process for producing the submerged arc furnace with low iron distribution and low silicon-magnesium ratio as claimed in any one of claims 1 to 6, which is characterized by comprising the following steps:

1) stacking the laterite-nickel ore in a wet field, conveying the laterite-nickel ore to a factory, taking the laterite-nickel ore by a loader, crushing and screening the laterite-nickel ore, and quantitatively conveying the laterite-nickel ore to a drying kiln;

2) drying wet ore by using the flue gas waste heat of the rotary kiln and the submerged arc furnace, and controlling the moisture within the range of 21-27%;

3) piling and taking the laterite-nickel ore subjected to the step 2) by a piling and taking machine, conveying the laterite-nickel ore to a batching workshop, and preparing the laterite-nickel ore dry ores with different grades, the coke and the coal powder into furnace burden according to the weight percentages of the components;

4) feeding laterite nickel ore and nut coke in the furnace burden prepared in the step 3) from the tail part of the rotary kiln, spraying coal powder in the furnace burden from the head part of the rotary kiln through the head part of the rotary kiln, and roasting and pre-reducing to obtain red hot calcine;

5) and (3) filling the red hot calcine into a heat-insulating material tank, transferring the red hot calcine into a submerged arc furnace for reduction smelting, heating and smelting by using an electrode, and controlling the sintering temperature to be between 730 and 760 ℃ according to the melting point and the production process of furnace burden to obtain the nickel-containing molten iron.

6) The process according to claim 7, wherein the production process of submerged arc furnace with low iron distribution and low silicon-magnesium ratio comprises the following steps: the moisture in the step 2) is controlled within the range of 22-23%.

8. The process of claim 7, wherein the production process of submerged arc furnace with low iron distribution and low silicon-magnesium ratio comprises the following steps: the process operation level is 12-15 levels, the operation voltage is 480-.

9. The process of claim 7, wherein the production process of submerged arc furnace with low iron distribution and low silicon-magnesium ratio comprises the following steps: the thickness of the material layer in the reduction smelting process is controlled to be 1.0-1.2m, and the clearance of the furnace core is 800-900 mm.

Technical Field

The invention relates to the technical field of submerged arc furnace smelting, in particular to a submerged arc furnace burden and a production process.

Background

In recent years, the price of nickel enters a drop-down passage under the influence of global economy, but the prices of raw materials such as coke and coal are still high, and in order to realize the optimization of cost and the maximization of capacity, the submerged arc furnace smelting needs to further innovate a process, control the production cost and improve the capacity, so that the development situation can be reached.

In the production process of a nickel-iron plant, the service life of the refractory materials of a plurality of submerged arc furnaces exceeds 6 years, the phenomena of great reduction of the depth of iron eyes, great increase of the temperature difference before and after tapping and obvious rise of the temperature difference of the water of the four-level water jacket occur in the furnaces, and the refractory materials are seriously deteriorated. If the prior production process is continued, the maintenance of the submerged arc furnace is obviously not facilitated, the abrasion of refractory materials is only more serious, and the service life is shorter; the conditions that the working condition of the refractory material of the rotary kiln is gradually worsened, the ring formation in the kiln is more and more serious and the operation rate is low are caused when the refractory material of the rotary kiln is used for more than 6 years, so that the difficulty is increased for the later use and maintenance of the refractory material, the production cost is increased, and the smelting capacity and quality of a ferronickel factory are restricted; the refractory materials are directly scrapped and are not used any more, which is a great waste.

In addition, in the production process of the furnace, the furnace cover is easy to blow fire and smoke, which causes great trouble to the cleanness of the production environment, is not beneficial to the health of surrounding workers and is not environment-friendly; and the temperature of the furnace cover is over-high, so that the failure of collapse of a refractory material of the furnace cover is easy to occur, the risks of deformation, cracking and the like of a girder of the furnace cover are easy to cause, the personal safety of operating personnel is threatened, and the nervous production operation is delayed.

Therefore, in order to solve the problems of high production cost, deteriorated furnace life, environmental protection, safe operation, frequent production faults and the like in the prior art, a protective furnace is urgently needed to be created in the hot furnace smelting of the ferronickel plant, so that the service life of the refractory material is prolonged, the nickel alloy cost can be fully controlled, and the production energy of the furnace burden and the production process can be improved.

Disclosure of Invention

Aiming at the defects and shortcomings in the background technology, the invention provides the furnace charge with low iron distribution and low silicon-magnesium ratio for the submerged arc furnace, and the furnace charge structure is adopted for production, so that the production cost can be obviously reduced, the service life of refractory materials is prolonged, the environmental protection problem that the furnace cover is easy to blow fire and smoke can be relieved, and the probability of furnace cover collapse can be greatly reduced.

The second purpose of the invention is to provide a low-iron-distribution and low-silicon-magnesium-ratio production process for the submerged arc furnace, which can reduce the production cost, prolong the service life of refractory materials, improve the operation rate of the whole rotary kiln, realize the maximization of the capacity of the rotary kiln, solve the environmental protection problem of furnace cover fire blow-by and smoke emission, greatly reduce the probability of furnace cover collapse accidents and realize the continuous and efficient operation of the submerged arc furnace.

In order to realize the purpose, the invention adopts the following technical scheme to realize the purpose:

the low-iron-distribution and low-silicon-magnesium-ratio furnace burden for the submerged arc furnace comprises laterite-nickel ore dry ores, coke breeze and coal powder, and is prepared from the laterite-nickel ore dry ores, the coke breeze and the coal powder with different grades according to the following components in percentage by weight:

NiO 2.0-2.4％，Fe₂O₃26.0-29.6％，SiO₂31.50-34.5％，MgO 19.0-21.5％，CaO0.28-0.5％，Al₂O₃2.06-4.03％，P 0.002-0.006％，S 0.025-0.055％，Cr₂O₃1.9-2.35%, and the balance other trace elementsAnd (4) measuring elements.

Further measures taken are: the furnace charge is prepared from the following components in percentage by weight:

NiO 2.0-2.2％，Fe₂O₃26.0-27.5％，SiO₂33.5-34.5％，MgO 20.6-21.5％，CaO0.3-0.4％，Al₂O₃3.0-3.8％，P 0.004-0.006％，S 0.035-0.045％，Cr₂O₃1.9-2.19%, and the balance of other trace elements.

Further measures taken are: the furnace charge is prepared from the following components in percentage by weight:

NiO 2.04％，Fe₂O₃26.43％，SiO₂34.32％，MgO 21.36％，CaO 0.35％，Al₂O₃3.27％，P 0.005％，S 0.04％，Cr₂O₃1.93%, and the rest is other trace elements.

Further measures taken are: the mass ratio of Fe to Ni in the furnace burden components is 11.82-12.96; the mass ratio of Si to Mg in the furnace burden components is 1.53-1.69.

Further measures taken are: the mass ratio of Fe to Ni in the furnace burden components is 12.96; the mass ratio of Si to Mg in the furnace burden components is 1.6.

Further measures taken are: the alkalinity of the components is 0.61-0.66.

The invention also provides a production process of the submerged arc furnace with low iron distribution and low silicon-magnesium ratio, which comprises the following steps:

1) stacking the laterite-nickel ore in a wet field, conveying the laterite-nickel ore to a factory, taking the laterite-nickel ore by a loader, crushing and screening the laterite-nickel ore, and quantitatively conveying the laterite-nickel ore to a drying kiln;

2) drying wet ore by using the flue gas waste heat of the rotary kiln and the submerged arc furnace, and controlling the moisture within the range of 21-27%;

3) piling and taking the laterite-nickel ore subjected to the step 2) by a piling and taking machine, conveying the laterite-nickel ore to a batching workshop, and preparing the laterite-nickel ore dry ores with different grades, the coke and the coal powder into furnace burden according to the weight percentages of the components;

4) feeding laterite nickel ore and nut coke in the furnace burden prepared in the step 3) from the tail part of the rotary kiln, spraying coal powder in the furnace burden from the head part of the rotary kiln through the head part of the rotary kiln, and roasting and pre-reducing to obtain red hot calcine;

5) and (3) filling the red hot calcine into a heat-insulating material tank, transferring the red hot calcine into a submerged arc furnace for reduction smelting, heating and smelting by using an electrode, and controlling the sintering temperature to be between 730 and 760 ℃ according to the melting point and the production process of furnace burden to obtain the nickel-containing molten iron.

Further measures taken are: the moisture in the step 2) is controlled within the range of 22-23%.

Further measures taken are: the process operation level is 12-15 levels, the operation voltage is 480-.

Further measures taken are: the thickness of the material layer in the reduction smelting process is controlled to be 1.0-1.2m, and the clearance of the furnace core is 800-900 mm.

Through the technical scheme, compared with the prior art, the invention has the following beneficial effects:

(1) the invention effectively inhibits the problem of 'fire fleeing and smoke generating' of the furnace cover in the production process of the furnace through low iron distribution, so that the production environment is cleaner and more environment-friendly, the temperature of the furnace cover is reduced to 800 ℃ from 880 ℃, thereby protecting the refractory material of the furnace cover and greatly reducing the probability of 'collapse' accident of the refractory material of the furnace cover.

(2) The invention reasonably prepares the components of the furnace charge, so that the iron distribution amount of the furnace charge is relatively not high due to the Fe distributed in the furnace charge₂O₃The amount of the refractory is low, and the refractory is of a low silicon-magnesium ratio type, so that the melting point of furnace burden is reasonably controlled, the potential safety hazard of ring formation of the rotary kiln is effectively controlled, refractory materials are protected, and the service life is prolonged.

(3) According to the invention, the working end of the electrode is easy to insert downwards through low iron distribution, the smelting current of the submerged arc furnace is more stable, and the power factor is as high as 0.99, so that the effective power is improved; the burning temperature of the rotary kiln calcine is controlled to be 730-760 ℃, so that the 3-valent iron of the calcine is promoted to be converted into 2-valent iron, the melting speed of furnace charge is improved, the power consumption is reduced, and the operation efficiency is improved by 7.1%.

(4) By the invention to Fe₂O₃And the grain size ratio of the coke oven and the coke oven is controlled, so that the using amount of the coke oven is integrally reduced by about 8.35 percent, the stability of smelting components of the submerged arc furnace is kept, the FeO of the furnace slag is stabilized, the temperature of the furnace slag is stabilized, and the stability of the furnace condition is kept.

(5) The process can continuously carry out the slag adhering process on the submerged arc furnace lining, reasonably control the slag adhering thickness of the lining, stabilize the depth of the iron eye between 1.1 and 1.5m, keep the temperature difference of the water jacket less than or equal to 3.5 ℃, and realize the continuous, safe and efficient operation of the submerged arc furnace lining.

Detailed Description

In order to clearly understand the technical solutions adopted by the present invention, the following description is made on the preferred embodiments of the present invention, and it should be understood that the embodiments described herein are only used for illustrating and explaining the present invention, and are not used to limit the present invention.