WO2021056905A1 - 一种两段式下降气流床炼铁系统及炼铁工艺 - Google Patents

一种两段式下降气流床炼铁系统及炼铁工艺 Download PDF

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WO2021056905A1
WO2021056905A1 PCT/CN2019/129539 CN2019129539W WO2021056905A1 WO 2021056905 A1 WO2021056905 A1 WO 2021056905A1 CN 2019129539 W CN2019129539 W CN 2019129539W WO 2021056905 A1 WO2021056905 A1 WO 2021056905A1
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inlet
furnace section
melting furnace
separator
reduction
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PCT/CN2019/129539
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English (en)
French (fr)
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马春元
赵媛
王涛
周滨选
周振峰
陈娟
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山东大学
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Priority to US17/295,965 priority Critical patent/US20220213567A1/en
Publication of WO2021056905A1 publication Critical patent/WO2021056905A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/0006—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/14—Multi-stage processes processes carried out in different vessels or furnaces
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/10—Making spongy iron or liquid steel, by direct processes in hearth-type furnaces

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  • the invention belongs to the technical field of metal smelting, and particularly relates to a two-stage downflow bed ironmaking process.
  • the blast furnace ironmaking method is currently the main method of producing steel, and its dominant position is not expected to change in the short term.
  • This method is a continuous metallurgical method for reducing iron ore to iron in a blast furnace.
  • the smelting process is as follows: load iron ore, coke, and flux for slagging from the top of the furnace according to the specified ratio, and make the furnace.
  • the throat material surface maintains a certain height, coke and ore form an alternating layered structure in the furnace, and the coke burns with the oxygen in the hot air blown in to generate carbon monoxide and hydrogen, and remove the oxygen in the iron ore during the ascent in the furnace.
  • iron is obtained by reduction, and it becomes a liquid at a high temperature above 2000°C.
  • the refined liquid molten iron flows out from the tap hole and solidifies to form a pig iron ingot.
  • the impurities in the iron ore and the flux combine to form slag, which is discharged from the tap hole.
  • the purpose of the present invention is to provide a two-stage downdraft bed ironmaking system and ironmaking process.
  • a two-stage downdraft bed ironmaking system including:
  • the melting furnace section is arranged vertically downward, the top of which is equipped with a basic combustion/gasifier, and a first inlet and a second inlet are arranged below the basic combustion/gasifier.
  • the first inlet and the second inlet are evenly along the sidewall of the melting furnace. Is arranged to form a tangent circle in the melting furnace section, the second inlet is located below the first inlet; the first inlet is connected with the coke/coal source, air source and water vapor source;
  • a slag pool is set at the bottom of the melting furnace section, a slag tapping device and an iron tapping device are set up in the slag pool, and the downstream of the slag pool is the outlet end;
  • the pre-reduction furnace section is arranged vertically downward, the top of which is connected with the outlet end of the melting furnace section, the third inlet and the fourth inlet are arranged above the pre-reduction furnace section, and the bottom is the outlet, and the third inlet is connected with the tempering and tempering medium Source connection, the fourth inlet is connected to the iron ore powder source;
  • the inlet of the first separator is connected with the outlet of the pre-reduction furnace section, and the outlet at the bottom of the separator is connected with the second inlet through a conveying pipe.
  • the pulverized coke/coal is carried by air and water vapor and enters the melting furnace section along the side wall of the melting furnace section, forming a swirling flow in the melting furnace section, and rotating downwards, and the burner sprays flames into the swirling flow.
  • the pulverized coal/coke powder is ignited or gasified to produce a high-temperature flame.
  • the high-temperature flame flows through the incoming pre-reduced ore powder fluid under the swirling flow. Two fluids with different moving speeds meet, collide, and then quickly mix uniformly.
  • the fluid spirally moves downwards As the fluid spirally moves downwards, the contact time between the pre-reduced iron ore powder and the high temperature and reducing gas is prolonged, thereby effectively increasing the degree of reduction of the iron ore powder, thereby increasing the iron smelting yield. Moreover, the fluid spirally moves downwards, which has a good carrying effect on the iron ore powder, which can effectively prevent the iron ore powder from settling in the melting furnace section, so that the iron ore powder and the air flow are evenly mixed, which is helpful for improving the iron smelting rate of the iron ore powder. More favorable.
  • the iron oxide in the iron ore powder is reduced to produce molten iron.
  • the molten iron and slag fall into the slag pool and are discharged through the iron tapping device and the slag tapping device.
  • the air flow out of the melting furnace section is cooled to a suitable temperature by the tempering and tempering medium entered from the third inlet, and then enters the pre-reduction furnace section, and contacts the incoming iron ore powder fluid to perform pre-reduction and pre-reduction of the iron ore powder.
  • the iron oxides in the iron ore powder mainly produce FeO, which is partially directly reduced to Fe, which is separated by a separator.
  • the pre-reduced iron ore powder is transported to the melting furnace section for high-temperature reduction. Due to the pre-reduction step , Can significantly improve the iron smelting yield of iron ore powder.
  • a funnel structure is provided at the bottom of the melting furnace section, and the slag pool is provided at the outlet end of the funnel structure.
  • the molten iron produced in the melting furnace section collects in the funnel structure and flows into the slag pool through the funnel structure. To ensure the smooth outflow of molten iron.
  • the first inlet includes 2-8 inlets, which are arranged along the circumference of the melting furnace section.
  • the second inlet includes 2-8 inlets, which are arranged along the circumference of the melting furnace section.
  • the pre-reduction furnace section and the melting furnace section are connected by arc-shaped pipes.
  • the arc-shaped pipe can gently change the flow direction of the reducing gas, and has little effect on the internal flow field of the gas flow.
  • Through the arc-shaped pipeline when the airflow from the melting furnace section flows through the pre-reduction furnace section, it can play a better role in turbulence and carry the iron ore powder added to the pre-reduction furnace section, so as to improve the iron ore powder The pre-reduction effect.
  • it further includes a second separator.
  • the inlet of the second separator is connected with the gas outlet of the first separator through a pipe.
  • the pipe is provided with a fifth inlet, and the fifth inlet is connected to a source of cold iron ore powder.
  • the higher-temperature air stream separated from the first separator flows through the fifth inlet, contacts with the cold iron ore powder added from the fifth inlet, heats the cold iron ore powder, and carries the cold iron ore powder to the second inlet.
  • the second separator, the gas-solid separation is carried out in the second separator. Preheating the cold iron ore powder is beneficial to the subsequent reduction of iron ore powder.
  • the solid outlet of the second separator is connected to the fourth inlet through a conveying pipe, and the gas outlet is connected to the first heat exchanger through a pipe.
  • the waste heat can be recovered at the position of the first heat exchanger to prevent the waste of heat.
  • the pulverized coal coking furnace section also includes a pulverized coal coking furnace section and a third separator.
  • the pulverized coal coking furnace section is arranged vertically, the bottom of which is connected with the gas outlet of the first separator, and the lower end is provided with a sixth inlet and a sixth inlet. It is connected with a source of pulverized coal, and its top is connected with the inlet of the third separator.
  • the hot air flow separated in the first separator can be used for heating and coking the pulverized coal.
  • the solid outlet end of the third separator is connected to the first inlet.
  • the separated coke powder is transported to the melting furnace section to participate in the reaction.
  • the gas outlet end of the third separator is connected to the second heat exchanger through a pipe.
  • the second heat exchanger is used to recover the waste heat of the hot air flow separated from the third separator to prevent the waste of heat.
  • a two-stage downdraft bed ironmaking process includes the following steps:
  • the coke powder/coal powder enters the melting furnace section from the side wall of the melting furnace section under the carrying effect of air and water vapor, and forms a swirling flow in the melting furnace section;
  • the basic combustion/gasifier on the top of the melting furnace section sprays flames inward to ignite or gasify the fluid to produce reducing gas;
  • the pre-reduced iron ore powder is sprayed into the melting furnace section and fully mixed with the coke powder/coal gas flow;
  • the iron oxide in the iron ore powder is reduced to elemental iron and melted into molten iron at high temperature;
  • the reduced high-temperature gas after the reaction flows into the pre-reduction furnace section from the melting furnace section, and pre-reduces the iron ore powder sprayed into the pre-reduction furnace section; the pre-reduced iron ore powder is transported to the melting furnace section.
  • the method further includes the step of preheating the cold iron ore powder by the high-temperature air flow from the pre-reduction furnace section.
  • the method further includes the step of coking the pulverized coal by the high-temperature air flow from the pre-reduction furnace section.
  • the reaction temperature of the melting furnace section is 1300-1700°C.
  • the temperature of the pre-reduction furnace section is 700-1100°C.
  • circulating gas or a mixture of pulverized coal and circulating gas is added to the pre-reduction furnace section as a cooling and temperature adjustment medium, and the proportion of reducing gas in the gas after tempering increases.
  • the pulverized ore pre-reduction furnace section cooperates with pulverized coal coking/gasification, pulverized coal/steam gasification medium or circulating gas cooperates with pulverized coal/steam to adjust temperature and gasify at the same time, and cool down and pulverized coal gasification/coking at the same time,
  • the coal gas quenching and tempering is realized, and more suitable reduction conditions are provided for the pre-reduction of the lower ore fines.
  • the coke powder and mineral powder are separated at the same time and sent to the melting furnace together.
  • the present invention provides a two-stage downflow bed ironmaking process, which is applied to the melting furnace section and the ore powder pre-reduction furnace section, and controls the temperature distribution in the two-stage furnace reactor according to the required conditions for the reduction of iron ore powder to molten iron ,
  • the high-temperature smelting reduction reaction occurs in the melting furnace section, and the molten iron is mainly generated from FeO
  • the pre-reduction reaction occurs in the pre-reduction furnace section of the ore powder
  • FeO or part of Fe is mainly generated from the iron ore powder.
  • This process realizes the pre-reduction and smelting reduction of the mineral powder, and both reactions are realized in the air flow down bed, which is beneficial to maintaining the uniform suspended state of the mineral powder particles and improving the reduction efficiency.
  • the process of converting iron ore into molten iron is completed in the same set of equipment, the complexity of the system is reduced, and the floor space is reduced.
  • Two temperature adjustment methods are proposed for the cooling and temperature adjustment of the inlet gas of the pre-reduction section.
  • the gas at the outlet of the melting furnace section is cooled by the circulating gas and then enters the pre-reduction furnace section of the ore powder.
  • Pulverized coal or circulating gas is used as a cooling and temperature adjustment medium at the same time.
  • the pre-reduction furnace section of ore powder cooperates with pulverized coal coking/gasification, pulverized coal/steam gasification medium or circulating gas cooperates with pulverized coal/steam to adjust the temperature at the same time.
  • Gasification, cooling and pulverized coal gasification/coking are carried out at the same time, which provides more suitable reduction conditions for the pre-reduction of the lower ore powder. In this case, the coke powder and mineral powder are separated at the same time and sent to the melting furnace together.
  • Two arrangements are proposed for the pre-reduced coal gas.
  • One is to set up a preheated cyclone separator for ore powder to exchange heat, increase the temperature of ore powder, which is beneficial to increase the degree of pre-reduction;
  • the other is to set up pulverized coal coking, which can be Expand the range of coal types, especially for lignite or bituminous coal with high moisture content. It can realize the short-process smelting of steel and has broad application prospects.
  • Figure 1 is a schematic structural diagram of a two-stage downflow bed ironmaking system according to a first embodiment of the present invention
  • Figure 2 is a schematic structural diagram of a two-stage downflow bed ironmaking system according to a second embodiment of the present invention
  • a two-stage downflow bed ironmaking process (arrangement 1) structure includes a melting furnace section 4, which is an airflow downflow bed, and a basic combustion/gasifier 1 is set on the top.
  • the upper side is the first inlet 2 for coke (coal) powder (air, water vapor), and a pre-reduction ore powder inlet-second inlet 3 is set at a distance below it;
  • the ore powder pre-reduction furnace section 8 is an airflow down bed, and the upper side On the side is the preheated ore powder inlet-the fourth inlet 7, and the lower part is connected to the inlet of the pre-reduced ore powder separator-the first separator 9;
  • the melting furnace section 4 and the ore powder pre-reduction furnace section 8 are connected through the slag pool 5; cooling adjustment
  • the warm conditioning medium inlet-the third inlet 6 is set at the connection pipe between the slag pool 5 and the slag pre-reduction furnace section 8; the upper outlet of the first separator 9 is connected
  • the basic combustion/gasifier burns/gasifies the fed coke (coal) powder (air, water vapor) to produce a high temperature of about 1600°C and a reducing atmosphere.
  • the pre-reduced iron ore powder mainly produces FeO in the smelting reduction furnace The reaction to produce molten iron, the molten iron falls into the slag pool.
  • the coke (coal) powder (air, water vapor) and pre-reduced mineral powder are sprayed in a four-corner tangent circle or a hexagonal tangent circle, which is conducive to uniform mixing.
  • the high-temperature coal gas produced in the melting furnace section is cooled and tempered by the cooling/conditioning medium, and then enters the ore powder pre-reduction furnace section.
  • the preheated ore powder is fed from the upper part of the furnace section.
  • the gas and preheated ore powder are mainly used to generate FeO and part of the ore powder.
  • the cooling/conditioning medium is circulating gas or circulating gas in cooperation with pulverized coal. Both of the above-mentioned two stages are airflow descending beds, which is beneficial for maintaining a uniform suspended state of the mineral powder particles and improving the reduction efficiency.
  • the coal gas and pre-reduced ore powder enter the inlet of the pre-reduced ore powder separator, the pre-reduced ore powder is separated from below the separator, and enters the melting furnace section through the pre-reduced ore powder inlet; the gas is separated from the upper side of the separator.
  • the coal gas discharged from the top of the pre-reduced ore powder separator carries the cold ore powder into the inlet of the preheated cyclone separator, the gas and the cold ore powder exchange heat, and the temperature of the cold ore powder increases, which is beneficial to improve the degree of pre-reduction.
  • the preheated ore powder is separated from the bottom of the separator and enters the pre-reduction furnace section of the ore powder; the coal gas is discharged from the upper part of the separator, and is discharged from the gas outlet pipe after passing through the gas heat exchanger.
  • a two-stage downflow bed ironmaking process device (arrangement mode 2) structure includes a melting furnace section 4, the melting furnace section 4 is an airflow down bed, a basic combustion/gasifier 1 is set on the top, and the upper side is coke powder ( Air, water vapor) inlet-first inlet 2, a pre-reduced mineral powder inlet-second inlet 3 is set at a distance below it; mineral powder pre-reduction furnace section 8 is a flow down bed, and the upper side is a mineral powder inlet-fourth Inlet 7, the lower part is connected to the inlet of the pre-reduction ore powder separator-the first separator 9; the melting furnace section 4 and the ore powder pre-reduction furnace section 8 are connected through the slag pool 5; the cooling and tempering medium inlet-the third inlet 6 is set At the connection pipe between the slag pool 5 and the slag pre-reduction furnace section 8; the upper outlet of the pre-reduced slag separator-the first separator
  • the basic combustion/gasifier burns/gasifies the fed coke powder (air, water vapor) to produce a high temperature and reducing atmosphere of about 1600°C.
  • the pre-reduced iron ore powder mainly produces FeO in the smelting reduction furnace to generate molten iron. Reaction, the molten iron falls into the slag pool.
  • Coke powder (air, water vapor) and pre-reduced mineral powder are sprayed in a four-corner tangent circle or a hexagonal tangent circle method, which is conducive to uniform mixing.
  • the high-temperature gas produced in the melting furnace section enters the ore powder pre-reduction furnace section after being cooled and tempered by the cooling/conditioning medium.
  • the ore powder is fed from the upper part of the furnace section.
  • the gas and ore powder are mainly used for pre-reduction of FeO and part of Fe from the ore powder. reaction.
  • Both of the above-mentioned two stages are airflow descending beds, which is beneficial for maintaining a uniform suspended state of the mineral powder particles and improving the reduction efficiency.
  • the coal gas and pre-reduced ore powder enter the inlet of the pre-reduced ore powder separator, the pre-reduced ore powder is separated from below the separator, and enters the melting furnace section through the pre-reduced ore powder inlet; the gas is separated from the upper side of the separator.
  • the coal gas discharged above the pre-reduced ore powder separator carries the pulverized coal into the pulverized coal coking furnace section, and the pulverized coal produces coke powder under the temperature and atmosphere provided by the gas, and the pyrolysis gas and coke powder go upstream into the coke powder separator.
  • Setting up the coking of pulverized coal can expand the range of coal types, especially lignite or bituminous coal with high moisture content.
  • the coke powder is separated from the bottom of the separator and enters the melting furnace section; the coal gas is discharged from the top of the separator, flows through the gas outlet pipe, and enters the gas heat exchanger.

Abstract

一种两段式下降气流床炼铁系统及炼铁工艺，包括：熔融炉段（4），竖向设下行置，其顶部设置基础燃烧/气化器（1），基础燃烧/气化器（1）下方设置第一入口（2）和第二入口（3），第一入口（2）和第二入口（3）均沿熔融炉段（4）侧壁均匀设置，在熔融炉段（4）内形成切圆，第二入口（3）位于第一入口（2）的下方；第一入口（2）与焦/煤粉源、空气源和水蒸汽源连接；熔融炉段（4）的底部设置渣池（5），渣池（5）设置出渣装置和出铁装置，渣池（5）的下游为出口端；预还原炉段（8），竖向下行设置，其顶部与熔融炉段（4）的出口端连接，预还原炉段（8）的上方设置第三入口（6）和第四入口（7），其底部为出口，第三入口（6）与调温调质介质源连接，第四入口（7）与铁矿粉源连接；以及，第一分离器（9），其入口与预还原炉段（8）的出口连接，其底部出口通过输送管道与所述第二入口（3）连接。该系统占地面积小，工艺流程短，具有广阔的应用前景。

Description

一种两段式下降气流床炼铁系统及炼铁工艺 技术领域
本发明属于金属冶炼技术领域，特别涉及到一种两段式下降气流床炼铁工艺。
背景技术
公开该背景技术部分的信息仅仅旨在增加对本发明的总体背景的理解，而不必然被视为承认或以任何形式暗示该信息构成已经成为本领域一般技术人员所公知的现有技术。
高炉炼铁法是目前生产钢铁的主要方法，其主导地位预计在短期内不会有所改变。该种方法是在高炉中把铁矿石还原成铁的一种连续冶金方法，冶炼工艺为：按规定的配比从炉顶装入铁矿石、焦炭、造渣用的熔剂，并使炉喉料面保持一定的高度，焦炭和矿石在炉内形成交替分层结构，焦炭同鼓入的热空气中的氧燃烧生成一氧化碳和氢气，在炉内上升过程中除去铁矿石中的氧，从而还原得到铁，并在2000℃以上的炽热高温中成为液体。炼出的液体铁水从出铁口流出，经凝固而形成生铁锭，铁矿石中的杂质和熔剂结合生成炉渣，从出渣口排出。
可见，高炉炼铁法中需要使用大量的优质焦炭，然而，焦煤资源日渐贫乏，冶金焦的价格越来越高，但储量丰富的廉价非焦煤资源却不能在炼铁生产中充分利用。为了改变炼铁对焦炭资源的依赖状况，研究者们探索了不同形式的非高炉炼铁法，初步形成了以直接还原和熔融还原为主体的现代非高炉炼铁工业体系。现有非高炉炼铁技术包括气体还原的直接还原方法、应用固体还原剂的直接还原方法，以及Corex工艺、Finex工艺、HIsmelt工艺等典型熔融还原流程，但上述工艺各自存在不同的问题，如还原效率低、余热回收率低、仍需要部分冶金焦炭等，没有实现工艺简单、低能耗的炼铁流程。
发明内容
为了解决现有技术中存在的技术问题，本发明的目的是提供一种两段式下降气流床炼铁系统及炼铁工艺。
为了实现上述目的，本发明的技术方案为：
一种两段式下降气流床炼铁系统，包括：
熔融炉段，竖向下行设置，其顶部设置基础燃烧/气化器，基础燃烧/气化器下方设置第一入口和第二入口，第一入口和第二入口均沿熔融炉段侧壁均匀设置，在熔融炉段内形成切圆，第二入口位于第一入口的下方；第一入口与焦/煤粉源、空气源和水蒸汽源连接；
熔融炉段的底部设置渣池，渣池设置出渣装置和出铁装置，渣池的下游为出口端；
预还原炉段，竖向下行设置，其顶部与熔融炉段的出口端连接，预还原炉段的上方设 置第三入口和第四入口，其底部为出口，第三入口与调温调质介质源连接，第四入口与铁矿粉源连接；
以及，第一分离器，其入口与预还原炉段的出口连接，其底部出口通过输送管道与所述第二入口连接。
焦粉/煤粉在空气和水蒸汽的携带作用下，沿熔融炉段的侧壁进入熔融炉段，在熔融炉段内形成旋流，并旋转向下运动，燃烧器向旋流喷射火焰，将煤粉/焦粉点燃或气化，产生高温火焰，高温火焰在旋流携带下流经进入的经过预还原的矿粉流体，两股运动速度不同的流体相遇、碰撞、进而迅速混合均匀。
由于流体螺旋向下运动，延长了预还原后的铁矿粉与高温、还原气体接触时间，进而可以有效提高铁矿粉的还原程度，进而提高炼铁产率。而且，流体螺旋向下运动，对铁矿粉起到良好的携带作用，可以有效防止铁矿粉在熔融炉段的沉降，使铁矿粉与气流混合均匀，对提高铁矿粉的炼铁率较为有利。
铁矿粉中的铁的氧化物经过还原后产生铁水，铁水和渣落入渣池中，通过出铁装置和出渣装置排出。
从熔融炉段流出的气流经过从第三入口进入的调温调质介质冷却至合适的温度后进入预还原炉段，与进入的铁矿粉流体接触，对铁矿粉进行预还原，预还原完成后，铁矿粉中的铁的氧化物主要生成FeO，部分直接还原成Fe，经分离器分离，经过预还原的铁矿粉被输送至熔融炉段进行高温还原，由于经过了预还原步骤，可以显著提高铁矿粉的炼铁收率。
在一些实施例中，所述熔融炉段的底部设置有漏斗结构，漏斗结构的出口端设置所述渣池。在熔融炉段产生的铁水在漏斗结构部位汇集，并通过漏斗结构流入渣池中。以保证铁水的顺利流出。
在一些实施例中，所述第一入口包括2-8个入口，沿熔融炉段的周向布置。
在一些实施例中，所述第二入口包括2-8个入口，沿熔融炉段的周向布置。
在一些实施例中，预还原炉段和熔融炉段通过弧形管道连接。弧形管道可以缓和地改变还原性气体的流向，对气流的内部流场影响较小。通过弧形管道，从熔融炉段流出的气流流经预还原炉段时，可以对加入到预还原炉段内的铁矿粉起到较好的扰流和携带作用，以提高对铁矿粉的预还原效果。
在一些实施例中，还包括第二分离器，第二分离器的进口与第一分离器的气体出口通过管道连接，管道上设置有第五入口，第五入口与冷铁矿粉源连接。
从第一分离器中分离出的较高温度的气流流经第五入口，与从第五入口加入的冷铁矿粉接触，对冷铁矿粉进行加热，并将冷铁矿粉携带至第二分离器，在第二分离器中进行气 固分离。对冷铁矿粉进行预热，对后续铁矿粉的还原炼铁较为有利。
进一步的，所述第二分离器的固体出口通过输送管道与所述第四入口连接，气体出口通过管道与第一换热器连接。
由于对冷铁矿粉进行预热后，气体的温度还较高，可以在第一换热器位置处进行余热回收，防止热量的浪费。
在一些实施例中，还包括煤粉焦化炉段和第三分离器，煤粉焦化炉段竖向设置，其底部与第一分离器的气体出口连接，其下端设置第六入口，第六入口与煤粉源连接，其顶部与所述第三分离器的进口连接。
可以利用第一分离器中分离出的热气流对煤粉进行加热焦化处理。
进一步的，所述第三分离器的固体出口端与所述第一入口连接。经过分离后的焦粉被输送至熔融炉段参与反应。
进一步的，所述第三分离器的气体出口端通过管道与第二换热器连接。
通过第二换热器对从第三分离器分离的热气流进行余热回收，防止热量的浪费。
一种两段式下降气流床炼铁工艺，包括如下步骤：
焦粉/煤粉在空气和水蒸汽的携带作用下，从熔融炉段的侧壁进入熔融炉段，在熔融炉段内形成旋流；
熔融炉段顶部的基础燃烧/气化器向内喷射火焰，将流体点燃或气化，产生还原性气体；
经过预还原的铁矿粉喷入熔融炉段内，与焦粉/煤粉气流充分混合；
在高温还原作用下，铁矿粉中的铁的氧化物还原为铁单质，并在高温下熔化为铁水；
反应后的还原性高温气体自熔融炉段流入预还原炉段，对喷入预还原炉段的铁矿粉进行预还原；预还原后的铁矿粉输送至熔融炉段。
在一些实施例中，还包括从预还原炉段流出的高温气流对冷铁矿粉进行预热的步骤。
在一些实施例中，还包括从预还原炉段流出的高温气流对煤粉进行焦化的步骤。
在一些实施例中，熔融炉段反应的温度为1300～1700℃。
在一些实施例中，预还原炉段的温度为700～1100℃。
在一些实施例中，向预还原炉段投加循环煤气或煤粉与循环煤气的混合物作为冷却调温介质，调质后气体中的还原性气体比例增加。
矿粉预还原炉段协同煤粉焦化/气化，煤粉/水蒸气气化介质或是循环煤气协同煤粉/水蒸气同时调温并气化，降温与煤粉气化/焦化同时进行，实现了煤气调质，为下部矿粉预还原提供更合适的还原条件。这种情况下，焦粉与矿粉同时分离，一起送入熔融炉。
本发明的有益效果为：
本发明提出一种两段式下降气流床炼铁工艺，应用于熔融炉段和矿粉预还原炉段，根据铁矿粉还原为铁水的所需条件，控制两段炉反应器内的温度分布，熔融炉段发生高温熔融还原反应，主要由FeO生成铁水，矿粉预还原炉段发生预还原反应，主要由铁矿粉生成FeO或部分Fe。此工艺实现了矿粉的预还原、熔融还原，两个反应均在气流下降床内实现，利于矿粉颗粒保持均匀的悬浮状态，有利于提高还原效率。铁矿石转化为铁水的过程在同一套装置内完成，系统的复杂程度减小，占地面积缩小。
对预还原段进口煤气的冷却调温提出了两种调温方式，采用循环煤气对熔融炉段出口的煤气经冷却介质冷却后进入矿粉预还原炉段。煤粉或与循环煤气同时用作冷却调温介质，矿粉预还原炉段协同煤粉焦化/气化，煤粉/水蒸气气化介质或是循环煤气协同煤粉/水蒸气同时调温并气化，降温与煤粉气化/焦化同时进行，为下部矿粉预还原提供更合适的还原条件。这种情况下，焦粉与矿粉同时分离，一起送入熔融炉。
对预还原后的煤气提出了两种布置方式，一种设置矿粉的预热旋流分离器换热，提高矿粉温度，有利于提高预还原度；另一种设置煤粉的焦化，可以扩大煤种适应范围，特别适应于褐煤或高水分的烟煤。能够实现钢铁的短流程冶炼，具有广阔的应用前景。
附图说明
构成本发明的一部分的说明书附图用来提供对本发明的进一步理解，本发明的示意性实施例及其说明用于解释本发明，并不构成对本发明的不当限定。
图1为本发明第一种实施例的两段式下降气流床炼铁系统的结构示意图；
图2为本发明第二种实施例的两段式下降气流床炼铁系统的结构示意图；
其中：1、基础燃烧/气化器；2、第一入口；3、第二入口；4、熔融炉段；5、渣池；6、第三入口；7、第四入口；8、预还原炉段；9、第一分离器；10、第五入口；11、第二分离器；12、第一换热器；13、煤气出口管；14、第六入口；15、煤粉焦化炉段；16、第三分离器；17、第二换热器。
具体实施方式
应该指出，以下详细说明都是示例性的，旨在对本发明提供进一步的说明。除非另有指明，本文使用的所有技术和科学术语具有与本发明所属技术领域的普通技术人员通常理解的相同含义。
需要注意的是，这里所使用的术语仅是为了描述具体实施方式，而非意图限制根据本发明的示例性实施方式。如在这里所使用的，除非上下文另外明确指出，否则单数形式也意图包括复数形式，此外，还应当理解的是，当在本说明书中使用术语“包含”和/或“包括”时，其指明存在特征、步骤、操作、器件、组件和/或它们的组合。
实施例1：
如图1所示，一种两段式下降气流床炼铁工艺的装置(布置方式1)结构包括熔融炉段4，熔融炉段4是气流下降床，顶部设置基础燃烧/气化器1，上方侧面为焦(煤)粉(空气、水蒸汽)的第一入口2，其下方一段距离处设置预还原矿粉入口-第二入口3；矿粉预还原炉段8为气流下降床，上方侧面为预热矿粉入口-第四入口7，下部连接预还原矿粉分离器-第一分离器9的入口；熔融炉段4和矿粉预还原炉段8通过渣池5连接；冷却调温调质介质入口-第三入口6设置在渣池5和矿粉预还原炉段8连接管道处；第一分离器9上方出口连接预热旋流分离器-第二分离器11入口，下方出口连接预还原矿粉入口-第二入口3；冷矿粉入口-第五入口10设置在预还原矿粉分离器-第一分离器9上方出口处；预热旋流分离器-第二分离器11下方出口连接预热矿粉入口-第四入口7，上方出口依次连接煤气换热器-第一换热器12和煤气出口管13。
上述两段式下降气流床(布置方式1)炼铁工艺的方法，具体步骤为：
1)高温熔融还原
基础燃烧/气化器燃烧/气化被送入的焦(煤)粉(空气、水蒸汽)，产生约1600℃的高温和还原性气氛，预还原铁矿粉在熔融还原炉内主要发生FeO生成铁水的反应，铁水落入渣池。焦(煤)粉(空气、水蒸汽)和预还原矿粉采用四角切圆或六角切圆的方式喷入，有利于混合均匀。
2)矿粉预还原
熔融炉段产生的高温煤气经冷却/调质介质冷却调质后进入矿粉预还原炉段，预热矿粉从炉段上方送入，煤气和预热矿粉主要进行矿粉生成FeO和部分Fe的预还原反应。所述冷却/调质介质是循环煤气，或是循环煤气协同煤粉。上述两段均为气流下降床，有利于矿粉颗粒保持均匀的悬浮状态，提高还原效率。
3)预还原矿粉分离
煤气和预还原矿粉进入预还原矿粉分离器入口，预还原矿粉从分离器下方分离，经预还原矿粉入口进入熔融炉段；煤气从分离器上方分离。
4)冷矿粉预热
预还原矿粉分离器上方排出的煤气携带冷矿粉进入预热旋流分离器入口，煤气和冷矿粉进行热量交换，冷矿粉温度提高，利于提高预还原度。预热矿粉从分离器下方分离，进入矿粉预还原炉段；煤气从分离器上方排出，经煤气换热器后从煤气出口管排出。
实施例2：
如图2所示为本申请的另一种实施方式。一种两段式下降气流床炼铁工艺的装置(布置方 式2)结构包括熔融炉段4，熔融炉段4是气流下降床，顶部设置基础燃烧/气化器1，上方侧面为焦粉(空气、水蒸汽)入口-第一入口2，其下方一段距离处设置预还原矿粉入口-第二入口3；矿粉预还原炉段8为气流下降床，上方侧面为矿粉入口-第四入口7，下部连接预还原矿粉分离器-第一分离器9入口；熔融炉段4和矿粉预还原炉段8通过渣池5连接；冷却调温调质介质入口-第三入口6设置在渣池5和矿粉预还原炉段8连接管道处；预还原矿粉分离器-第一分离器9上方出口连接煤粉焦化炉段15，下方出口连接预还原矿粉入口-第二入口3；煤粉焦化炉段15下方设置煤粉入口-第六入口14，上方连接焦粉分离器-第三分离器16入口；焦粉分离器-第三分离器16下方出口连接焦粉(空气、水蒸汽)入口-第一入口2，上方出口依次连接煤气出口管13和第二换热器17。
本申请另一种两段式下降气流床(布置方式2)炼铁工艺的方法，具体步骤为：
1)高温熔融还原
基础燃烧/气化器燃烧/气化被送入的焦粉(空气、水蒸汽)，产生约1600℃的高温和还原性气氛，预还原铁矿粉在熔融还原炉内主要发生FeO生成铁水的反应，铁水落入渣池。焦粉(空气、水蒸汽)和预还原矿粉采用四角切圆或六角切圆的方式喷入，有利于混合均匀。
2)矿粉预还原
熔融炉段产生的高温煤气经冷却/调质介质冷却调质后进入矿粉预还原炉段，矿粉从炉段上方送入，煤气和矿粉主要进行矿粉生成FeO和部分Fe的预还原反应。上述两段均为气流下降床，有利于矿粉颗粒保持均匀的悬浮状态，提高还原效率。
3)预还原矿粉分离
煤气和预还原矿粉进入预还原矿粉分离器入口，预还原矿粉从分离器下方分离，经预还原矿粉入口进入熔融炉段；煤气从分离器上方分离。
4)煤粉焦化
预还原矿粉分离器上方排出的煤气携带煤粉进入煤粉焦化炉段，在煤气提供的温度和气氛下煤粉制得焦粉，热解气和焦粉上行进入焦粉分离器。设置煤粉的焦化，可以扩大煤种适应范围，特别适应于褐煤或高水分的烟煤。焦粉从分离器下方分离，进入熔融炉段；煤气从分离器上方排出，流经煤气出口管后进入煤气换热器。
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (10)

  1. 一种两段式下降气流床炼铁系统，其特征在于：包括：
    熔融炉段，竖向下行设置，其顶部设置基础燃烧/气化器，基础燃烧/气化器下方设置第一入口和第二入口，第一入口和第二入口均沿熔融炉段侧壁均匀设置，在熔融炉段内形成切圆，第二入口位于第一入口的下方；第一入口与焦/煤粉源、空气源和水蒸汽源连接；
    熔融炉段的底部设置渣池，渣池设置出渣装置和出铁装置，渣池的下游为出口端；
    预还原炉段，竖向下行设置，其顶部与熔融炉段的出口端连接，预还原炉段的上方设置第三入口和第四入口，其底部为出口，第三入口与调温调质介质源连接，第四入口与铁矿粉源连接；
    以及，第一分离器，其入口与预还原炉段的出口连接，其底部出口通过输送管道与所述第二入口连接。
  2. 根据权利要求1所述的两段式下降气流床炼铁系统，其特征在于：所述熔融炉段的底部设置有漏斗结构，漏斗结构的出口端设置所述渣池。
  3. 根据权利要求1所述的两段式下降气流床炼铁系统，其特征在于：所述第一入口包括2-8个入口，沿熔融炉段的周向布置；
    或，所述第二入口包括2-8个入口，沿熔融炉段的周向布置。
  4. 根据权利要求1所述的两段式下降气流床炼铁系统，其特征在于：预还原炉段和熔融炉段通过弧形管道连接。
  5. 根据权利要求1所述的两段式下降气流床炼铁系统，其特征在于：还包括第二分离器，第二分离器的进口与第一分离器的气体出口通过管道连接，管道上设置有第五入口，第五入口与冷铁矿粉源连接；
    进一步的，所述第二分离器的固体出口通过输送管道与所述第四入口连接，气体出口通过管道与第一换热器连接。
  6. 根据权利要求1所述的两段式下降气流床炼铁系统，其特征在于：还包括煤粉焦化炉段和第三分离器，煤粉焦化炉段竖向设置，其底部与第一分离器的气体出口连接，其下端设置第六入口，第六入口与煤粉源连接，其顶部与所述第三分离器的进口连接；
    进一步的，所述第三分离器的固体出口端与所述第一入口连接；
    进一步的，所述第三分离器的气体出口端通过管道与第二换热器连接。
  7. 一种两段式下降气流床炼铁工艺，其特征在于：包括如下步骤：
    焦粉/煤粉在空气和水蒸汽的携带作用下，从熔融炉段的侧壁进入熔融炉段，在熔融炉段内形成旋流；
    熔融炉段顶部的基础燃烧/气化器向内喷射火焰，将流体点燃或气化，产生还原性气体；
    经过预还原的铁矿粉喷入熔融炉段内，与焦粉/煤粉气流充分混合；
    在高温还原作用下，铁矿粉中的铁的氧化物还原为铁单质，并在高温下熔化为铁水；
    反应后的还原性高温气体自熔融炉段流入预还原炉段，对喷入预还原炉段的铁矿粉进行预还原；预还原后的铁矿粉输送至熔融炉段。
  8. 根据权利要求7所述的两段式下降气流床炼铁工艺，其特征在于：还包括从预还原炉段流出的高温气流对冷铁矿粉进行预热的步骤；
    或，还包括从预还原炉段流出的高温气流对煤粉进行焦化的步骤。
  9. 根据权利要求7所述的两段式下降气流床炼铁工艺，其特征在于：熔融炉段反应的温度为1300～1700℃；
    或，预还原炉段的温度为700～1100℃。
  10. 根据权利要求7所述的两段式下降气流床炼铁工艺，其特征在于：向预还原炉段投加循环煤气或煤粉与循环煤气的混合物作为冷却调温介质。
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Families Citing this family (3)

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Publication number Priority date Publication date Assignee Title
CN110578029B (zh) * 2019-09-25 2020-11-10 山东大学 一种两段式下降气流床炼铁系统及炼铁工艺
CN114574651B (zh) * 2022-01-24 2023-05-05 山东大学 一种旋流铁壁熔融冶炼装置及方法
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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6749664B1 (en) * 2001-01-26 2004-06-15 Midrex International, B.V., Rotterdam, Zurich Branch Furnace hearth for improved molten iron production and method of operation
CN101519707A (zh) * 2008-02-28 2009-09-02 宝山钢铁股份有限公司 一种粉铁矿预还原工艺以及多级流化床
CN102206725A (zh) * 2011-05-05 2011-10-05 刘元生 二步法生产还原铁粉的工艺
CN202007243U (zh) * 2011-01-25 2011-10-12 吴道洪 煤制还原气流化床还原钒钛磁铁矿粉系统
CN103074460A (zh) * 2013-01-05 2013-05-01 莱芜钢铁集团有限公司 一种分段处理铁矿石的转底炉设备及处理方法
CN106868245A (zh) * 2017-03-13 2017-06-20 武汉科思瑞迪科技有限公司 一种两步法的铁水生产工艺
WO2017199868A1 (ja) * 2016-05-20 2017-11-23 株式会社神戸製鋼所 還元鉄の製造方法
CN110218831A (zh) * 2019-06-27 2019-09-10 山东大学 一种充分预热和气相预还原的煤气化协同熔融铁还原装置及方法
CN110578029A (zh) * 2019-09-25 2019-12-17 山东大学 一种两段式下降气流床炼铁系统及炼铁工艺

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5948841B2 (ja) * 1982-03-31 1984-11-29 川崎製鉄株式会社 溶融還元設備における粉粒状予備還元鉱石の移送装置
JP2536217B2 (ja) * 1990-02-27 1996-09-18 日本鋼管株式会社 溶融還元設備における予備還元炉の分散盤下面に付着したダストの除去装置
CN100560739C (zh) * 2006-09-29 2009-11-18 宝山钢铁股份有限公司 一种综合利用煤气和粉矿的熔融还原炼铁工艺
DE102006048601A1 (de) * 2006-10-13 2008-04-17 Voest-Alpine Industrieanlagenbau Gmbh & Co Verfahren und Vorrichtung zur Herstellung von geschmolzenem Material
JP5948841B2 (ja) * 2011-12-13 2016-07-06 株式会社富士通ゼネラル 冷媒回路ユニット
CN105543437A (zh) * 2012-10-24 2016-05-04 沈阳东方钢铁有限公司 一种两段式气流床铁矿粉还原工艺
CN109371189A (zh) * 2018-11-02 2019-02-22 中国石油大学(华东) 铁矿粉和煤粉y型气流床分级还原气化炼铁工艺
CN109321703B (zh) * 2018-11-02 2023-09-29 河北燕山钢铁集团有限公司 一种短流程熔融还原炼铁系统及方法

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6749664B1 (en) * 2001-01-26 2004-06-15 Midrex International, B.V., Rotterdam, Zurich Branch Furnace hearth for improved molten iron production and method of operation
CN101519707A (zh) * 2008-02-28 2009-09-02 宝山钢铁股份有限公司 一种粉铁矿预还原工艺以及多级流化床
CN202007243U (zh) * 2011-01-25 2011-10-12 吴道洪 煤制还原气流化床还原钒钛磁铁矿粉系统
CN102206725A (zh) * 2011-05-05 2011-10-05 刘元生 二步法生产还原铁粉的工艺
CN103074460A (zh) * 2013-01-05 2013-05-01 莱芜钢铁集团有限公司 一种分段处理铁矿石的转底炉设备及处理方法
WO2017199868A1 (ja) * 2016-05-20 2017-11-23 株式会社神戸製鋼所 還元鉄の製造方法
CN106868245A (zh) * 2017-03-13 2017-06-20 武汉科思瑞迪科技有限公司 一种两步法的铁水生产工艺
CN110218831A (zh) * 2019-06-27 2019-09-10 山东大学 一种充分预热和气相预还原的煤气化协同熔融铁还原装置及方法
CN110578029A (zh) * 2019-09-25 2019-12-17 山东大学 一种两段式下降气流床炼铁系统及炼铁工艺

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