CN112683059A - Preheating type submerged arc furnace for producing large-crystal fused magnesia - Google Patents

Preheating type submerged arc furnace for producing large-crystal fused magnesia Download PDF

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Publication number
CN112683059A
CN112683059A CN202110142310.7A CN202110142310A CN112683059A CN 112683059 A CN112683059 A CN 112683059A CN 202110142310 A CN202110142310 A CN 202110142310A CN 112683059 A CN112683059 A CN 112683059A
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China
Prior art keywords
furnace
grate
flue gas
cover
submerged arc
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Inventor
徐吉龙
邓乐锐
赵金秋
章荣会
杨海峰
李娜
李玺
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Xiuyan Manzu Autonomous County Hengrui Magnesium Products Co ltd
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Xiuyan Manzu Autonomous County Hengrui Magnesium Products Co ltd
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Priority to CN202110142310.7A priority Critical patent/CN112683059A/en
Publication of CN112683059A publication Critical patent/CN112683059A/en
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Abstract

The invention provides a preheating type submerged arc furnace for producing large-crystal fused magnesia, which comprises a furnace body, a furnace cover, a smoke collecting pipeline, a feeding chute, a grate sealing cover and a grate machine, wherein the top of the furnace body is provided with the furnace cover, the side wall of the furnace cover is provided with a smoke hole connected with the smoke collecting pipeline and a blanking hole connected with the feeding chute, the other end of the smoke collecting pipeline is connected with the grate sealing cover, the grate machine is arranged in the grate sealing cover, and the other end of the feeding chute is provided with the grate machineOne end of the chain grate extends into the sealing cover of the chain grate machine and is connected with the chain grate machine. The invention can realize flue gas recovery of the large-crystal fused magnesia ore heating furnace, and uses flue gas waste heat to preheat raw materials, wherein natural magnesite powder can be predecomposed by high-temperature flue gas to release most CO in advance2Gas, increase its proportion of addition. The invention can also realize automatic feeding through monitoring of the temperature of the flue gas.

Description

Preheating type submerged arc furnace for producing large-crystal fused magnesia
Technical Field
The invention relates to a production and processing device of macrocrystalline fused magnesia, in particular to a preheating type submerged arc furnace for producing macrocrystalline fused magnesia.
Background
At present, most large-crystal electric melting magnesia takes high-quality light-burned magnesia powder as a main raw material, is added into a submerged arc furnace hearth with an open furnace top in a manual feeding mode, and is smelted by using three electrodes fixed by hanging or cross arms.
In the production process, with the continuous heating and melting of the raw materials, new light-burned magnesia powder needs to be continuously supplemented into the furnace barrel, and the work is generally subjectively judged by experienced workers and manually added. Because the top of the furnace barrel is of an open structure, hot flue gas can fly out of the furnace barrel with light-burned magnesia powder in the charging process, the flue gas can permeate a workshop, the field operation environment is extremely severe, and the physical health of workers is directly harmed.
Another disadvantage of manual charging is that workers need to continuously pay attention to the conditions in the furnace for a long time, and magnesium oxide powder is frequently added into the furnace barrel according to the smelting condition in the furnace, so that the labor intensity is high, fatigue operation is easy, and the danger coefficient is high. Meanwhile, the control of feeding time and feeding amount is directly influenced by human factors, which easily causes the fluctuation of furnace conditions in the smelting process and influences the quality of finished products and the ratio of large-crystal magnesia.
Meanwhile, the open furnace top structure also enables the waste heat of the flue gas to be dissipated to the environment, thereby not only increasing the environmental risk of field operation, but also wasting a large amount of heat energy.
In order to solve the problems, a small amount of large-crystal electric smelting magnesia ore heating furnace equipment is additionally provided with a furnace cover and an automatic feeding system in order to adopt a new technology. The top of the furnace barrel is subjected to certain sealing treatment, so that the smoke is limited in the furnace barrel, the diffusion of smoke and dust and the outward dissipation of heat are reduced, the field operation environment and the utilization rate of heat energy are improved, the power consumption is saved, the smelting efficiency is improved, and the smelting cost is reduced. According to the preset program, the light-burned magnesia powder raw material can be added into the furnace barrel in a timed and quantitative manner, so that the unstable factor of manual addition is avoided. The sintering efficiency is improved, so that the product quality is more stable.
According to the scheme, the raw materials entering the furnace are not preheated by utilizing the waste heat of the smoke gas in the smelting process, and meanwhile, even if a preset program automatic feeding process is adopted, only the timed and quantitative feeding is realized, and the proper feeding time and the feeding amount cannot be judged according to the real-time furnace condition.
Disclosure of Invention
The invention provides a preheating type submerged arc furnace for producing large-crystal fused magnesia, which solves the problems of preheating raw materials and charging according to real-time furnace conditions, and adopts the following technical scheme:
the utility model provides a production macrocrystal fused magnesia's hot stove in preheating-type ore deposit, includes furnace body, bell, flue gas collecting pipe way, feeding elephant trunk, chain grate sealing cover and chain grate machine, the furnace body top sets up the bell, and the lateral wall of bell has the flue gas hole with flue gas collecting pipe way to and the unloading hole that is connected with the feeding elephant trunk, the other end of flue gas collecting pipe is connected with chain grate sealing cover, inside chain grate machine that is provided with of chain grate sealing cover, the other end of feeding elephant trunk stretches into after the chain grate sealing cover, is connected with the chain grate machine.
The height of the smoke hole is higher than that of the blanking hole.
The vertical section of the flue gas collecting pipeline is provided with a thermocouple, and the chain grate machine controls feeding into the furnace body according to the temperature signal of the thermocouple.
And a material baffle plate is arranged on the upper part of the chain grate machine and used for scraping materials and uniformly spreading the materials on the chain grate.
The tail outlet of the sealing cover of the chain grate is connected with the dust remover through a pipeline.
The inner wall of the flue gas collecting pipeline is provided with a heat insulation refractory material, and the flue gas collecting pipeline extends upwards in an inclined mode and then forms a vertical direction.
The flue gas collecting pipeline changes the vertical direction into the horizontal direction, reaches the upper end of the sealing cover of the chain grate machine and is connected with the sealing cover of the chain grate machine.
The top of the furnace cover is a refractory furnace cover prefabricated part with an electrode insertion hole, and a gap between an electrode and the electrode hole is sealed by using a combined sealing ring.
A ceramic fiber sealing washer is arranged between the furnace cover and the furnace body, and a refractory material layer is arranged on the inner wall of the furnace cover.
The preheating type submerged arc furnace for producing the macrocrystalline fused magnesia has the following advantages:
(1) the furnace top is closed, so that the heat loss is reduced, smoke dust is prevented from flying out of the furnace, and the field operation environment is improved;
(2) the ceramic fiber gasket and the electrode sealing ring further reduce the loss of smoke in the furnace;
(3) flue gas in the furnace is uniformly recovered through a closed pipeline, and the raw materials entering the furnace are preheated through a chain grate in advance, so that the temperature of the raw materials entering the furnace is increased, and the smelting power consumption is reduced;
(4) a sealing cover is arranged outside the chain grate machine, and a heat-insulating refractory material is arranged on the inner wall of the sealing cover;
(5) the high-temperature flue gas can decompose the natural magnesite powder and release most of CO in advance2The gas can improve the proportion of magnesite powder replacing light-burned magnesia powder and reduce the cost of raw materials;
(6) the automatic control of the chain grate machine is realized by monitoring the temperature of the flue gas so as to finish the operation of automatically adding raw materials into the submerged arc furnace.
Drawings
FIG. 1 is a schematic view of the preheating type ore furnace for producing large-size crystallized fused magnesite;
the reference numbers in the figures: 1. a trolley; 2. a furnace body; 3. a sealing gasket; 4. a furnace cover; 5. a flue gas collection duct; 6. a seal ring; 7. a furnace cover prefabricated part; 8. an electrode; 9. a feeding chute; 10. a grate seal enclosure; 11. a chain grate machine.
Detailed Description
As shown in figure 1, the preheating type submerged arc furnace for producing the macrocrystalline fused magnesia comprises a furnace body 2, a furnace cover 4, a flue gas collecting pipeline 5, a feeding elephant trunk 9, a grate sealing cover 10 and a grate 11, wherein the furnace cover 4 is arranged at the top of the furnace body 2, a flue gas hole connected with the flue gas collecting pipeline 5 is formed in the side wall of the furnace cover 4, and a discharging hole connected with the feeding elephant trunk 9 is formed in the side wall of the furnace cover 4, the height of the flue gas hole is slightly higher than that of the discharging hole, so that fine powder is prevented from being brought out by the flue. The other end of the flue gas collecting pipeline 5 is connected with a chain grate sealing cover 10, a chain grate 11 is arranged in the chain grate sealing cover 10, and the flue gas is finally introduced into the head part of the chain grate 11 through the flue gas collecting pipeline 5. The other end of the feeding chute 9 extends into the sealing cover 10 of the chain grate machine and is connected with the outlet of the chain grate machine 11.
And a ceramic fiber sealing washer 3 is arranged between the lower part of the furnace cover 4 and the top of the furnace body 2 to enhance the sealing effect. The inner wall of the furnace cover 4 is provided with a refractory material layer which plays roles of heat insulation and external steel shell protection. The top of the furnace cover 4 is a refractory furnace cover prefabricated part 7 with an electrode insertion hole, a gap between an electrode 8 and the electrode hole is sealed by using a combined sealing ring 6, the sealing ring 6 is sleeved by two pieces, and an inner hole formed by combination has the same diameter as the electrode and can be placed tightly to the electrode 8.
In the furnace cover 4, a flue gas collecting pipe 5 connected with the furnace cover 4 extends upwards in an inclined mode at first, and then a section of vertical pipe is formed, so that fine powder brought out by flue gas can slide back into the furnace easily. The inner wall of the flue gas collecting pipeline 5 is provided with a heat insulation refractory material, so that heat loss of flue gas in the pipeline is reduced.
And a thermocouple is arranged at the vertical section of the flue gas collecting pipeline 5 and is used for monitoring the temperature of the flue gas. The grate 11 realizes the automatic control of feeding into the furnace body according to the temperature signal. The flue gas temperature can rise gradually along with the powder melting progress in the furnace body, and when the flue gas temperature reached and set up the upper limit temperature, drying grate 11 automatic start carried the raw materials to the furnace body through feeding elephant trunk 9. The flue gas temperature will gradually decrease during the charging process, and when the flue gas temperature reaches the set lower limit temperature, the charging operation will be automatically stopped by the grate 11.
When the powder material spreading machine works, the powder material is fed onto the chain grate through the inlet at the tail part of the chain grate 11, and is strickled off by the material baffle plate at the upper part of the chain grate and is uniformly spread on the chain grate along with the advancing process of the chain grate. The high-temperature flue gas collected by the closed flue gas collecting pipeline 5 is introduced into the sealing cover 10 of the chain grate machine from the head of the chain grate machine 11 to heat the raw material spread on the chain grate, the raw material is heated and pre-decomposed, and finally the high-temperature flue gas flows out from the head of the chain grate machine 11 and enters the furnace body 2 through the feeding chute 9. The grate machine 11 is externally provided with a grate machine sealing cover 10, and the low-temperature flue gas is finally introduced into the dust remover through a tail outlet positioned at the grate machine sealing cover 10.
The production of large-crystal fused magnesia mainly uses light-burned magnesia powder as a main raw material, and less uses natural magnesite. Because the main component of the natural magnesite is MgCO3Decomposition reaction occurs at 350 ℃, MgCO3Complete decomposition will release about 52.3% of CO2And a large amount of gas is released in a centralized manner, so that splashing and material collapse in the furnace are easily caused, and finally, the furnace shell is burnt through. Based on this, the existing large-crystal electric melting magnesite production mostly uses light-burned magnesia powder as a main raw material, and uses little or even no natural magnesite powder. Magnesite powder can be pre-decomposed by utilizing the waste heat of high-temperature flue gas, almost all CO is heated and decomposed before entering a furnace barrel2The gas is released in advance, and violent reaction can not be generated in the furnace. The addition of magnesite powder greatly reduces the cost of raw materials.
The invention can realize flue gas recovery of the large-crystal fused magnesia ore heating furnace, and uses flue gas waste heat to preheat raw materials, wherein natural magnesite powder can be predecomposed by high-temperature flue gas to release most CO in advance2Gas, increase its proportion of addition. Has the following characteristics:
1. this technical scheme adds the lid to open furnace tube and seals. The hot flue gas in the furnace is intensively recycled and is introduced into the preheater to preheat the raw material, so that the temperature of the raw material entering the furnace is improved, the heating time is shortened, the power consumption is saved, and the smelting speed and efficiency are improved.
2. Meanwhile, the high-temperature flue gas can also predefine the raw materials, so that the direct use of natural magnesite powder to produce macrocrystalline fused magnesia becomes possible.
3. According to the change of the temperature of the flue gas in the submerged arc furnace, the automatic control of feeding into the furnace is realized.

Claims (9)

1.一种生产大结晶电熔镁砂的预热式矿热炉,其特征在于:包括炉体、炉盖、烟气收集管道、进料溜管、链篦机密封罩和链篦机,所述炉体顶部设置炉盖,炉盖的侧壁有与烟气收集管道的烟气孔,以及与进料溜管相连接的下料孔,所述烟气收集管道的另一端与链篦机密封罩相连接,所述链篦机密封罩内部设置有链篦机,所述进料溜管的另一端伸入到链篦机密封罩后,与链篦机相连接。1. a preheated submerged arc furnace for producing large crystal fused magnesia, is characterized in that: comprise furnace body, furnace cover, flue gas collection pipeline, feeding chute, chain grate seal cover and chain grate, The top of the furnace body is provided with a furnace cover, and the side wall of the furnace cover has a flue gas hole connected with the flue gas collection pipe and a discharge hole connected with the feed chute. The other end of the flue gas collection pipe is connected to the chain grate. The grate seal cover is connected with the chain grate seal cover, the chain grate machine is arranged inside the chain grate machine seal cover, and the other end of the feed chute extends into the chain grate machine seal cover and is connected with the chain grate machine. 2.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述烟气孔的高度高于下料孔。2 . The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1 , wherein the height of the flue gas hole is higher than the discharge hole. 3 . 3.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述烟气收集管道竖直段部位设置有热电偶,链篦机根据热电偶的温度信号控制向炉体内的加料。3. The preheated submerged arc furnace for producing large-crystal fused magnesia according to claim 1, wherein the vertical section of the flue gas collection pipe is provided with a thermocouple, and the grate is arranged according to the temperature of the thermocouple. The temperature signal controls the feeding into the furnace body. 4.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述链篦机的链篦上部设置有挡料板,用于将物料刮平并均匀铺展在链篦上。4. The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1, characterized in that: the upper part of the grate of the grate machine is provided with a baffle plate, which is used for scraping the material and making it smooth. Spread evenly on the grate. 5.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述链篦机密封罩的尾部出口通过管道与除尘器相连接。5 . The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1 , characterized in that: the tail outlet of the grate seal cover is connected to the dust collector through a pipeline. 6 . 6.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述烟气收集管道内壁设置隔热耐火材料,所述烟气收集管道斜向上延伸后再形成竖直方向。6. The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1, characterized in that: the inner wall of the flue gas collection pipe is provided with heat-insulating refractory materials, and the flue gas collection pipe extends obliquely upward Then form the vertical direction. 7.根据权利要求6所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述烟气收集管道在竖直方向改为水平方向,到达链篦机密封罩的上端,与链篦机密封罩相连接。7. The preheated submerged arc furnace for producing large-crystal fused magnesia according to claim 6, wherein the flue gas collection pipe is changed to a horizontal direction in the vertical direction, and reaches the end of the grate seal cover. The upper end is connected with the grate seal cover. 8.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述炉盖的顶部为带有电极插入孔的耐火材料炉盖预制件,电极与电极孔之间的缝隙使用组合式密封圈进行封堵。8. The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1, characterized in that: the top of the furnace cover is a refractory furnace cover prefabricated with electrode insertion holes, and the electrodes are The gap between the electrode holes is sealed with a combined sealing ring. 9.根据权利要求1所述的生产大结晶电熔镁砂的预热式矿热炉,其特征在于:所述炉盖与炉体之间有陶瓷纤维密封垫圈,炉盖的内壁设置有耐火材料层。9. The preheated submerged arc furnace for producing large crystal fused magnesia according to claim 1, characterized in that: a ceramic fiber sealing gasket is arranged between the furnace cover and the furnace body, and the inner wall of the furnace cover is provided with a refractory material layer.
CN202110142310.7A 2021-02-02 2021-02-02 Preheating type submerged arc furnace for producing large-crystal fused magnesia Pending CN112683059A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113405366A (en) * 2021-07-22 2021-09-17 魏振平 System and process for smelting sub-vacuum electric melting magnesium oxide and capturing and recovering carbon dioxide

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CN111365997A (en) * 2020-04-13 2020-07-03 岫岩满族自治县恒锐镁制品有限公司 A furnace top sealing device for producing large crystal fused magnesia ore furnace
CN214406946U (en) * 2021-02-02 2021-10-15 岫岩满族自治县恒锐镁制品有限公司 Preheating type ore-smelting furnace for producing large-crystal fused magnesia

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Publication number Priority date Publication date Assignee Title
EP2107327A2 (en) * 2008-04-02 2009-10-07 Javier Guiu Lapresta Thermal gas flow control system in the electric arc furnace
CN104748558A (en) * 2013-12-27 2015-07-01 中冶长天国际工程有限责任公司 Tailing preheating device of reduction kiln
CN105987601A (en) * 2015-02-14 2016-10-05 佟玉鹏 Short-flow high titanium slag smelting submerged arc furnace
CN106399619A (en) * 2016-06-08 2017-02-15 江苏省冶金设计院有限公司 High-temperature chain grate and rotary hearth furnace united direct reduction system and high-temperature chain grate and rotary hearth furnace united direct reduction method
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113405366A (en) * 2021-07-22 2021-09-17 魏振平 System and process for smelting sub-vacuum electric melting magnesium oxide and capturing and recovering carbon dioxide

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