CN209292387U - Preparation system of shaft furnace reducing gas - Google Patents

Abstract

The utility model provides a reduction gas preparation system for a shaft furnace, which at least includes hydrogen generating equipment, an entrained flow gasification furnace, a heat exchanger, a mixer, first cooling and purification equipment and second cooling and purification equipment. The utility model utilizes high-temperature gasification synthesis gas coupled with direct reduction of iron to produce hydrogen, does not need expensive catalysts, has low cost, high thermal efficiency, and does not need a CO conversion device, and uses a heat exchanger to transfer the heat of high-temperature synthesis gas to hydrogen, so that The hydrogen is heated, so that the sensible heat of the high-temperature and high-pressure syngas generated by the gasifier can be fully utilized. Compared with the traditional process of first cooling down, desulfurizing and decarbonizing, and then changing the temperature, it saves investment, greatly reduces energy consumption, and reduces Operating costs.

Description

Shaft Furnace Reducing Gas Preparation System

technical field

The utility model relates to the technical field of iron and steel metallurgy, in particular to a reduction gas preparation system for a shaft furnace.

Background technique

The combination of blast furnace ironmaking process and converter forms a high-efficiency and large-scale steel production process, which is the main force of steel production in the world. However, due to its long process, high energy consumption, heavy pollution, and the need to consume coke, the development space is gradually limited. Countries around the world have begun to turn to non-blast furnace steelmaking technology and develop short-process electric furnace steelmaking with scrap steel and direct reduced iron as raw materials. It is an environmentally friendly and resource-saving steelmaking technology. In this technology, direct reduced iron can dilute the carbon, copper, manganese, zinc and other impurities in scrap steel, and the market demand in developed countries in Europe and America is particularly large. At present, the world's advanced direct reduction iron technology is the direct reduction technology of gas-based shaft furnace. This technology mainly uses natural gas as raw material. After being transformed into a gas rich in H2 and CO, it directly undergoes solid-state reduction with iron ore at high temperature to produce sponge. Iron (direct reduced iron). Due to the lack of natural gas resources in my country, the development of gas-based shaft furnace reduction technology is limited. my country's coal resources are relatively rich, and the development of coal gasification gas for the production of sponge iron in gas-based shaft furnaces is the preferred technical route in line with my country's national conditions, and is an important direction for the development of new ironmaking technology in my country.

Generally speaking, the requirements for reducing gas for direct reduction ironmaking in shaft furnaces are that the total integral of _H2 and CO is greater than 90%, φ(H2)/φ(CO) is 1.0-4.0, and the pressure is 0.15Mpa-0.60Mpa . None of the existing coal gasification processes can directly provide the gas components that meet the requirements, and CO conversion equipment is needed to adjust the gas components, and there are generally disadvantages such as high pressure in the gasifier, strict requirements on raw materials, high gas production costs, and high energy consumption. . In order to meet the requirements of reducing gas, the current gasification technology requires pure oxygen gasification with fixed bed or fluidized bed, supporting decarburization and CO conversion equipment, which needs to be cooled first and then heated up, resulting in waste of energy and high energy consumption. The entrained bed gasification technology has a high furnace temperature and produces CO+H ₂ >90%. It does not need decarbonization equipment, but only needs CO conversion equipment to increase the hydrogen content, which also causes energy waste and high energy consumption.

Utility model content

The purpose of the utility model is to provide a shaft furnace reducing gas preparation system capable of reducing energy consumption and utilizing heat reasonably.

In order to achieve the above object, the utility model provides a preparation system for the reduction gas of the shaft furnace, which at least includes:

Hydrogen generating equipment, which has a synthesis gas inlet, a water vapor inlet, a direct reduced iron inlet and a hydrogen exhaust outlet;

An entrained bed gasifier having a syngas vent;

A heat exchanger having a synthesis gas inlet, a synthesis gas outlet, a hydrogen inlet, and a hydrogen outlet, the synthesis gas inlet being in communication with the synthesis gas outlet, the hydrogen inlet being in communication with the hydrogen outlet;

a mixer having a first inlet, a second inlet and a reducing gas outlet, the hydrogen outlet being in communication with the first inlet;

The first cooling and purification equipment has a third inlet, a synthesis gas purification outlet and a steam outlet, the third inlet communicates with the synthesis gas outlet, and the synthesis gas purification outlet is respectively connected to the The second inlet communicates with the synthesis gas inlet, and the steam outlet communicates with the steam inlet;

The second cooling and purification equipment has a top gas inlet and a top gas purification outlet, and the top gas purification outlet is in communication with the first inlet.

The system for preparing reducing gas from a shaft furnace as described above, wherein the hydrogen generating equipment includes:

A first reactor, which is provided with a first feed port, a first feed port, the synthesis gas inlet and a discharge port, and the discharge port communicates with the outside world;

The second reactor is provided with the direct reduced iron inlet, the second feed port, the second discharge port, the steam inlet and the hydrogen exhaust port, the second feed port is connected to the The first material outlet is connected, and the second material outlet is connected with the first material inlet.

The system for preparing reducing gas of the shaft furnace as described above, wherein a condenser is provided between the hydrogen gas exhaust port and the hydrogen gas inlet.

In the above-mentioned shaft furnace reducing gas preparation system, wherein, the first reactor is a moving bed reactor or a fluidized bed reactor, and the second reactor is a moving bed reactor or a fluidized bed reactor.

The system for preparing reducing gas from a shaft furnace as described above, wherein the first cooling and purification equipment includes a waste heat boiler, a dust removal device, and a desulfurization device connected in sequence, the waste heat boiler is a shell-and-tube heat exchanger, and the steam The outlet and the third inlet are arranged on the waste heat boiler, and the outlet of the desulfurization device communicates with the second inlet and the synthesis gas inlet respectively through the two connecting pipelines.

The system for preparing reducing gas from a shaft furnace as described above, wherein the second cooling and purification equipment includes a scrubber and a purification device connected in sequence, the top gas inlet is arranged on the scrubber, and the purification device The outlet communicates with the first inlet.

The preparation system for shaft furnace reducing gas as described above, wherein, the purification device includes a gas pressurization device and a desulfurization and decarburization device connected in sequence, the inlet of the gas pressurization device communicates with the scrubber, the The outlet of the desulfurization and decarbonization device communicates with the first inlet.

The shaft furnace reducing gas preparation system described above, wherein the shaft furnace reducing gas preparation system further includes a shaft furnace, the shaft furnace includes a furnace body, and the furnace body is provided with an iron ore inlet, a furnace roof Gas outlet, reducing gas inlet and direct reduced iron outlet, the top gas outlet is connected to the top gas inlet, the reducing gas inlet is connected to the reducing gas outlet, and the direct reduced iron inlet can be connected to the The direct reduced iron outlets are connected.

Compared with prior art, the utility model has the following advantages:

The shaft furnace reduction gas preparation system provided by the utility model uses high-temperature gasification synthesis gas coupled with direct reduction iron to produce hydrogen, the components are adjustable, no need to use expensive catalysts, the cost is low, the thermal efficiency is high, and no CO conversion device is needed. The heat exchanger transfers the heat of the high-temperature syngas to the hydrogen, so that the hydrogen is heated, so that the sensible heat of the high-temperature and high-pressure syngas generated by the gasifier can be fully utilized. Compared with the traditional process, the temperature is first lowered for desulfurization and decarburization, and then the temperature is changed. Compared, saving investment, greatly reducing energy consumption, and reducing operating costs.

Description of drawings

The following drawings are only intended to illustrate and explain the utility model schematically, and do not limit the scope of the utility model. in:

Fig. 1 is a schematic structural diagram of a shaft furnace reducing gas preparation system of the present invention.

Explanation of reference numbers:

1. Hydrogen generation equipment;

11. The first reactor; 111. The first feed port; 112. The first discharge port; 113. The synthesis gas inlet; 114. The discharge port;

12. Second reactor; 121. Direct reduced iron inlet; 122. Second feed port; 123. Second discharge port; 124. Water vapor inlet; 125. Hydrogen exhaust port;

13. Condenser;

2. Entrained bed gasifier; 21. Syngas exhaust port;

3. Heat exchanger; 31. Syngas inlet; 32. Syngas outlet; 33. Hydrogen inlet; 34. Hydrogen outlet;

4. Mixer; 41. First inlet; 42. Second inlet; 43. Reducing gas outlet;

5. First cooling and purification equipment; 51. Waste heat boiler; 511. Third inlet; 512. Water vapor outlet; 52. Dust removal device; 53. Desulfurization device; 531. Syngas purification outlet;

6. Second cooling and purification equipment; 61. Scrubber; 611. Furnace top gas inlet; 62. Purification device; 621. Furnace top gas purification outlet;

7. Shaft furnace; 71. Furnace body; 711. Iron ore inlet; 712. Top gas outlet; 713. Reducing gas inlet; 714. Direct reduced iron outlet.

Detailed ways

In order to have a clearer understanding of the technical scheme, purpose and effect of the utility model, the specific implementation of the utility model will now be described in conjunction with the accompanying drawings.

As shown in Figure 1, the utility model provides a preparation system for reducing gas in a shaft furnace, which at least includes a hydrogen generating device 1, an entrained bed gasifier 2, a heat exchanger 3, a mixer 4, and a first cooling and purification device 5 and the second cooling and purification equipment 6, wherein the hydrogen generating equipment 1 has a synthesis gas inlet 113, a water vapor inlet 124, a direct reduced iron inlet 121 and a hydrogen exhaust port 125, and the hydrogen generating equipment 1 can generate hydrogen through a chemical reaction; The bed gasifier 2 has a synthesis gas exhaust port 21. The entrained bed gasifier 2 is a prior art, and its specific structure will not be repeated here; the heat exchanger 3 has a synthesis gas inlet 31, a synthesis gas outlet 32, and a hydrogen inlet. 33 and hydrogen outlet 34, specifically, the heat exchanger 3 is a shell-and-tube heat exchanger, the hydrogen inlet 33 and the hydrogen outlet 34 are arranged at both ends of the heat transfer tube of the heat exchanger 3, the synthesis gas inlet 31 and the synthesis gas outlet 32 is arranged on both sides of the shell of the heat exchanger 3, the synthesis gas inlet 31 communicates with the synthesis gas exhaust port 21, the hydrogen inlet 33 communicates with the hydrogen exhaust port 125, and the heat of the synthesis gas can be transferred to the heat exchanger 3 Internally transfer the hydrogen generated by the hydrogen generating equipment to heat the hydrogen; the mixer 4 has a first inlet 41, a second inlet 42 and a reducing gas outlet 43, and the hydrogen outlet 34 communicates with the first inlet 41; the first cooling and purification equipment 5 It has a third inlet 511, a synthesis gas purification outlet 531 and a water vapor outlet 512, the third inlet 511 is in communication with the synthesis gas outlet 32, and the synthesis gas purification outlet 531 is respectively connected to the second inlet 42 and the synthesis gas inlet 113 through two connecting pipelines The water vapor outlet is connected with the water vapor inlet 124, and the first cooling and purification equipment 5 can perform secondary cooling treatment on the synthesis gas, and can generate water vapor from the absorbed heat, and the generated water vapor can be transported to the hydrogen gas The generation equipment 1 produces hydrogen, and at the same time, the first cooling and purification equipment 5 can filter the impurities in the synthesis gas; the second cooling and purification equipment 6 has a furnace top gas inlet 611 and a furnace top gas purification outlet 621, and the furnace top gas purification outlet 621 and The first inlet 41 is connected, and the second cooling and purification equipment 6 is capable of cooling and purifying the furnace top gas, and the cooled and purified top gas, purified synthesis gas and heated hydrogen are mixed in the mixer 4 to form a vertical Furnace reducing gas.

When in use, feed the top gas into the second cooling and purification equipment 6, the top gas is a hydrogen-rich gas with a temperature of 300°C to 500°C, and the top gas enters the mixer 4 after being cooled and purified by the second cooling and purification equipment 6, The synthesis gas produced by the entrained bed gasification furnace 2 first enters the heat exchanger 3, exchanges heat with hydrogen, and then enters the first cooling and purification equipment 5, and part of the synthesis gas cooled and purified by the first cooling and purification equipment 5 enters the mixer 4, The other part enters the hydrogen generating equipment 1, and the water vapor produced by the first cooling and purifying equipment 5 absorbing the heat of the synthesis gas also enters the hydrogen generating equipment 1, and feeds the direct reduced iron into the hydrogen generating equipment 1, and the temperature of the direct reduced iron is 550°C ~800°C, the reaction of direct reduced iron, water vapor and synthesis gas in the hydrogen generator is as follows:

Fe ₃ O ₄ +4CO=3Fe+4CO ₂ , △H=-13kJ/mol;

Fe ₃ O ₄ +4H ₂ =3Fe+4H ₂ O, △H=151kJ/mol;

3Fe+4H ₂ O=Fe ₃ O ₄ +4H ₂ , △H=-151kJ/mol;

The generated hydrogen passes through the heat exchanger 3 and then enters the mixer 4. The direct reduced iron is used as an iron-based oxygen carrier to circulate and react in the hydrogen generation device to generate pure hydrogen. After the efficiency of the direct reduced iron decreases, fresh hydrogen can be added. The direct reduced iron is replaced, and the purified top gas, the heated hydrogen and the syngas after cooling and purification are mixed in the mixer 4, and the shaft furnace reducing gas is formed after adjusting the temperature and composition.

The shaft furnace reduction gas preparation system provided by the utility model uses high-temperature gasification synthesis gas coupled with direct reduction iron to produce hydrogen, without using expensive catalysts, low cost, high thermal efficiency, and does not require a CO conversion device. The heat of the synthesis gas is transferred to the hydrogen, so that the hydrogen is heated, so that the sensible heat of the high-temperature and high-pressure synthesis gas generated by the gasifier can be fully utilized. Compared with the traditional process of first cooling down, desulfurization and decarburization, and then changing the temperature, it saves investment , greatly reducing energy consumption and reducing operating costs.

In a preferred embodiment of the present utility model, as shown in Figure 1, the hydrogen generating device 1 includes a first reactor 11 and a second reactor 12, wherein:

The first reactor 11 is provided with a first feed port 111, a first feed port 112, a synthesis gas inlet 113, and a discharge port 114. The discharge port 114 is connected to the outside world, and the generated _{CO and H 2 O} are collected and passed through the discharge port. 114 is discharged; the second reactor 12 is provided with the direct reduced iron inlet 121, the second feed inlet 122, the second discharge outlet 123, the water vapor inlet 124 and the hydrogen exhaust outlet 125, the second feed inlet 122 and the first The material outlet 112 is connected, the second material outlet 123 is connected with the first material inlet 111, and the reaction occurring in the first reactor 11 is: Fe ₃ O ₄ +4CO=3Fe+4CO ₂ , ΔH= -13kJ/mol; Fe ₃ O ₄ +4H ₂ =3Fe+4H ₂ O, △H=151kJ/mol; the reaction occurring in the second reactor 12 is: 3Fe+4H ₂ O=Fe ₃ O ₄ +4H ₂ , △H=-151kJ/mol, that is, direct reduction of iron and water vapor react to generate H ₂ and Fe ₃ O ₄ , and the generated Fe ₃ O ₄ is sent to the first reactor 11 and the CO and H ₂ in the synthesis gas The reaction generates Fe (including part of FeO) and CO ₂ , H ₂ O, and Fe (part of FeO) returns to the second reactor 12 for reaction to produce hydrogen. This cycle reaction produces pure hydrogen at low cost.

It should be noted that, according to the amount of hydrogen gas lacking in the detection mixer 4, the amount of synthesis gas introduced into the first reactor 11 is determined, so that the hydrogen generated by the hydrogen generating device can meet the needs of the mixer 4 to produce vertical gas. The furnace reducing gas lacks the amount of hydrogen. In order to detect the composition of the gas in the mixer 4, a detection device can be installed at the reducing gas outlet 43 of the mixer 4.

Further, in order to prevent the moisture in the hydrogen produced by the hydrogen generating device from affecting the quality of the shaft furnace reducing gas, a condenser 13 is provided between the hydrogen exhaust port 125 and the hydrogen inlet 33, and the water in the hydrogen is removed through the condenser 13 , so that the hydrogen gas entering the mixer 4 is a dry gas, so as to ensure the quality of the shaft furnace reducing gas produced.

Further, the first reactor 11 is a moving bed reactor or a fluidized bed reactor, the first reactor 11 mainly undergoes a reduction reaction, and the reaction temperature is 600°C to 900°C, and the second reactor 12 is a moving bed reactor or a fluidized bed reactor. In the chemical bed reactor, the second reactor 12 mainly produces oxidation reaction, the reaction temperature is 550°C-850°C, the oxidation reaction is an exothermic reaction, and the input direct reduced iron can provide heat for the oxidation reaction.

Further, the first cooling and purification equipment 5 includes a waste heat boiler 51, a dust removal device 52 and a desulfurization device 53 connected in sequence, the waste heat boiler 51 is a shell-and-tube heat exchanger, and the water vapor outlet 512 and the third inlet 511 are arranged on the waste heat boiler 51 , the heat transfer tube of the waste heat boiler 51 is water, and the synthesis gas passes into the shell of the waste heat boiler 51 through the third inlet 511, and the water in the heat transfer tube of the waste heat boiler 51 is heated into steam by the synthesis gas, and the inlet of the dust removal device 52 It is connected with the outlet of the shell of the waste heat boiler 51, the outlet of the dedusting device 52 is connected with the inlet of the desulfurization device 53, and the syngas is filtered and dedusted through the dedusting device 52. Therefore, the specific structure of the dust removal device 52 will not be repeated here. The outlet of the desulfurization device 53 is respectively connected with the second inlet 42 and the synthesis gas inlet 113 through two connecting pipelines. Part of the synthesis gas enters the mixer 4 through a connecting pipeline, and the other part enters the first reactor 11 through another connecting pipeline to circulate to produce hydrogen. Specifically, dry desulfurization is adopted, and a desulfurizing agent FeO or ZnO is used for desulfurization, using wet desulfurization, adding lye to the desulfurization device 53, and absorbing the sulfur in the synthesis gas through the lye.

Further, the second cooling and purification equipment 6 includes a scrubber 61 and a purification device 62 connected in sequence. The top gas inlet 611 is arranged on the scrubber 61, and the top gas is washed, cooled and dust-removed through the scrubber 61. The purification device 62 The outlet is connected to the first inlet 41, and the top gas after cooling and dedusting treatment is desulfurized and decarburized by the purification device 62, so that the top gas entering the mixer 4 is relatively pure, so as to ensure that the produced shaft furnace reducing gas the quality of.

Further, the purification device 62 includes a gas pressurization device and a desulfurization and decarbonization device connected in sequence, the inlet of the gas pressurization device is connected with the outlet of the scrubber 61, the outlet of the gas pressurization device is connected with the inlet of the desulfurization and decarbonization device, The outlet of the desulfurization and decarbonization device is connected to the first inlet 41. Specifically, MDEA (methyldiethanolamine, methyldiethanolamine) solution is added into the desulfurization and decarbonization device, and the sulfur and carbon mixed in the top gas can be absorbed by the MDEA solution.

In one embodiment of the present utility model, the preparation system of the shaft furnace reducing gas further includes a shaft furnace 7, the shaft furnace 7 includes a furnace body 71, and the furnace body 71 is provided with an iron ore inlet 711, a furnace top gas outlet 712, The reducing gas inlet 713 and the direct reduced iron outlet 714, the iron ore inlet 711 is located at the top of the furnace body 71, the direct reduced iron outlet 714 is located at the bottom of the furnace body 71, the furnace top gas outlet 712 and the reducing gas inlet 713 are arranged from top to bottom Between the iron ore inlet 711 and the direct reduced iron outlet 714, the furnace top gas outlet 712 is connected with the furnace top gas inlet 611, the reducing gas inlet 713 is connected with the reducing gas outlet 43, the direct reduced iron inlet 121 is connected with the direct reduced iron The outlet 714 is connected, and the shaft furnace 7 is preferably a gas-based shaft furnace comprising Midrex (Midrex) and HYL (Hill). , the iron ore enters from the iron ore inlet 711 of the furnace, wherein the iron ore is pellets or lump ore, and the reducing gas of the shaft furnace flows from bottom to top, and the reduction reaction of iron ore occurs, and the reaction temperature is 850°C to 1000°C, Obtain direct reduced iron and top gas, the generated top gas is a hydrogen-rich gas with a temperature of 300°C to 500°C, the temperature of direct reduced iron is 550°C to 800°C, and the direct reduced iron produced by shaft furnace 7 is used as an oxygen carrier It can be directly input into the second reactor 12 through the pipeline, and the cost is low, and the shaft furnace reducing gas generated by the mixer 4 can be directly passed into the shaft furnace 7 through the reducing gas inlet 713 for reaction to produce direct reduced iron.

It should be noted that, in the above-mentioned shaft furnace reducing gas preparation system, it is preferable to use pipelines to communicate with each other.

The use process of the preparation system of the shaft furnace reducing gas provided by the utility model is specifically described below in conjunction with the accompanying drawings:

As shown in Figure 1, when in use, the hydrogen-rich top gas with a temperature of 300°C to 500°C generated by the shaft furnace 7 is passed into the second cooling and purification equipment 6, and the top gas is cooled by the second cooling and purification equipment 6 After dedusting, desulfurization and decarburization treatment, it enters the mixer 4, and the synthesis gas generated by the entrained bed gasifier 2 first enters the heat exchanger 3, and after exchanging heat with hydrogen, enters the first cooling and purification equipment 5, and passes through the first cooling and purification equipment 5 for two A part of the syngas after the secondary temperature reduction and dedusting and desulfurization treatment enters the mixer 4, and another part of the syngas enters the first reactor 11, and the water vapor generated by the waste heat boiler 51 absorbing the heat of the syngas enters the second reactor 12, while the second The reactor 12 is passed into the shaft furnace 7 to generate direct reduced iron at a temperature of 550°C to 800°C. The reaction between the direct reduced iron and water vapor in the second reactor 12 is: 3Fe+4H ₂ O=Fe ₃ O ₄ +4H ₂ , △H=-151kJ/mol, transport the generated Fe ₃ O ₄ to the first reactor 11, the reaction of Fe ₃ O ₄ and synthesis gas in the first reactor 11 is: Fe ₃ O ₄ +4CO＝3Fe+4CO ₂ , △H＝-13kJ/mol; Fe ₃ O ₄ +4H ₂ ＝3Fe+4H ₂ O, △H＝151kJ/mol; feed the generated Fe (part of FeO) into the first reaction 11, so that the first reactor 11 and the second reactor 12 can form a cyclic reaction to continuously produce pure hydrogen, and after the efficiency of the direct reduced iron decreases, it can be replaced by fresh direct reduced iron generated by the shaft furnace 7, After being condensed and dewatered by the condenser 13, the pure hydrogen enters the heat exchanger 3 and is heated by the high-temperature synthesis gas, and the purified furnace top gas, the heated hydrogen, and the synthesis gas after cooling and purification are mixed in the mixer 4 , after adjusting the temperature and composition to form the shaft furnace reducing gas.

In addition, in FIG. 1, the arrow direction is the flow direction of gas or the movement direction of direct reduced iron.

The utility model also provides a method for preparing the reducing gas of the shaft furnace, which adopts the above-mentioned preparation system for the reducing gas of the shaft furnace, and the method for preparing the reducing gas of the shaft furnace includes:

Feed the top gas into the top gas inlet of the second cooling and purification equipment for cooling and purification treatment, that is, perform cooling and dust removal, desulfurization and decarbonization treatment on the top gas;

Pass the cooled and purified furnace top gas into the mixer;

The syngas generated by the entrained bed gasifier is cooled and purified through the heat exchanger and the first cooling and purification equipment in turn, that is, the high-temperature syngas generated by the entrained bed gasifier is subjected to two cooling treatments and dedusting and desulfurization treatment;

Pass a part of the syngas after the cooling and purification treatment into the mixer, and pass the other part of the syngas, water vapor generated by the first cooling and purification equipment and direct reduced iron into the hydrogen generation equipment to produce hydrogen, that is, according to the amount of hydrogen required by the mixer , feed an appropriate amount of synthesis gas into the hydrogen generating equipment to produce the required hydrogen;

The hydrogen generated by the hydrogen generation equipment and the synthesis gas generated by the entrained bed gasifier are passed into the heat exchanger for heat exchange treatment, that is, the hydrogen is heated by the high-temperature synthesis gas;

Pass the hydrogen after heat exchange into the mixer;

The furnace top gas after the cooling and purification treatment, a part of the syngas after the cooling and purification treatment and the hydrogen after heat exchange are mixed in the mixer to form the reducing gas.

The preparation method of the shaft furnace reducing gas provided by the utility model adopts the preparation system of the above-mentioned shaft furnace reducing gas, therefore, the preparation method of the shaft furnace reducing gas has all the advantages of the above-mentioned preparation system of the shaft furnace reducing gas, and the shaft furnace reducing gas The preparation method has the advantages of simple and convenient operation.

Furthermore, the gasification temperature of the entrained bed gasifier is 1300°C-1800°C, the gasification pressure of the entrained bed gasifier is 0.5MPa-3.0MPa, and the reaction temperature of the hydrogen generation equipment is 600°C-900°C, so as to meet the requirements of various Conditions required for a chemical reaction.

Further, the top gas inlet of the second cooling and purification equipment is connected with the top gas outlet of the furnace body of the shaft furnace, and the reducing gas outlet of the mixer is connected with the reducing gas inlet of the furnace body of the shaft furnace, so that the furnace top The gas can continuously enter the second cooling and purification equipment. Since the direct reduced iron is recycled as the oxygen carrier, it only needs to be replenished regularly and does not need to enter the reactor. The amount of direct reduced iron depends on the composition of the furnace top gas and the vertical The reducing gas of the furnace needs to be determined. The preparation system of the reducing gas of the shaft furnace starts to work, and it can be replenished regularly. Therefore, the direct reduced iron outlet of the furnace body of the shaft furnace can be connected with the direct reduced iron inlet of the hydrogen generation equipment through a pipeline. It is also possible to manually transport the direct reduced iron produced by the shaft furnace to the hydrogen generation equipment.

Among them, the top gas generated in the shaft furnace is a hydrogen-rich gas with a temperature of 300°C to 500°C, and the temperature of the direct reduced iron is 550°C to 800°C.

Further, a heating device may be provided between the reducing gas outlet and the reducing gas inlet of the furnace body of the shaft furnace, so that the temperature of the shaft furnace reducing gas passing into the shaft furnace meets the usage requirements.

In summary, the shaft furnace reduction gas preparation system provided by the utility model uses high-temperature gasification synthesis gas coupled with direct reduction of iron to produce hydrogen, with adjustable components, no need to use expensive catalysts, low cost, high thermal efficiency, and no need for The CO conversion device uses a heat exchanger to transfer the heat of the high-temperature synthesis gas to the hydrogen, so that the hydrogen is heated, so that the sensible heat of the high-temperature and high-pressure synthesis gas generated by the gasifier can be fully utilized, which is different from the traditional process of first cooling, desulfurization and decarbonization , Compared with changing the temperature and heating, it saves investment, greatly reduces energy consumption, and reduces operating costs.

The preparation method of the shaft furnace reducing gas provided by the utility model adopts the preparation system of the above-mentioned shaft furnace reducing gas, therefore, the preparation method of the shaft furnace reducing gas has all the advantages of the above-mentioned preparation system of the shaft furnace reducing gas, and the shaft furnace reducing gas The preparation method has the advantages of simple and convenient operation.

The above descriptions are only illustrative specific implementations of the present utility model, and are not intended to limit the scope of the present utility model. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention shall fall within the protection scope of the present invention. And it should be noted that each component of the utility model is not limited to the above-mentioned overall application, and each technical feature described in the specification of the utility model can be selected to be used alone or in combination according to actual needs. Therefore, The utility model naturally covers other combinations and specific applications related to the invention point of the case.

Claims (8)

1. a kind of preparation system of reducing gas for shaft furnace, which is characterized in that the preparation system of the reducing gas for shaft furnace includes at least:

Hydrogen generating device, with synthesis gas import, vapor import, direct reduced iron entrance and hydrogen exhaust mouth；

Airflow bed gasification furnace, with synthesis gas exhaust outlet；

Heat exchanger, with synthesis gas entrance, syngas outlet, hydrogen inlet and hydrogen outlet, the synthesis gas entrance and institute It states synthesis gas exhaust outlet to be connected, the hydrogen inlet is connected with the hydrogen exhaust mouth；

Mixer is connected with first entrance, second entrance and also Primordial Qi outlet, the hydrogen outlet with the first entrance It is logical；

First cooling, purifying equipment, with third entrance, purified synthesis gas outlet and steam outlet, the third entrance with The syngas outlet is connected, purified synthesis gas outlet by two connecting lines respectively with the second entrance and described Synthesis gas import is connected, and the vapor outlet is connected with the vapor import；

Second cooling, purifying equipment, with top gas entrance and top gas purge outlet, the top gas purge outlet and institute First entrance is stated to be connected.

2. the preparation system of reducing gas for shaft furnace according to claim 1, which is characterized in that

The hydrogen generating device includes:

First reactor is equipped with first charging aperture, the first discharge port, the synthesis gas import and discharge outlet, the discharge outlet It is in communication with the outside；

Second reactor is equipped with the direct reduced iron entrance, second charging aperture, the second discharge port, the vapor import With the hydrogen exhaust mouth, the second charging aperture is connected with first discharge port, second discharge port and described the One feed inlet is connected.

3. the preparation system of reducing gas for shaft furnace according to claim 2, which is characterized in that

Condenser is equipped between the hydrogen exhaust mouth and the hydrogen inlet.

4. the preparation system of reducing gas for shaft furnace according to claim 2, which is characterized in that

The first reactor is moving-burden bed reactor or fluidized-bed reactor, and the second reactor is moving-burden bed reactor Or fluidized-bed reactor.

5. the preparation system of reducing gas for shaft furnace according to claim 2, which is characterized in that

The first cooling, purifying equipment includes the waste heat boiler, dust-extraction unit and desulfurizer being sequentially communicated, the waste heat boiler Furnace is shell-and-tube heat exchanger, and the steam outlet and the third entrance are arranged on the waste heat boiler, the desulfurization dress The outlet set is connected with the second entrance and the synthesis gas import respectively by two connecting lines.

6. the preparation system of reducing gas for shaft furnace according to claim 1, which is characterized in that

The second cooling, purifying equipment includes the washer and purification device being sequentially communicated, and the top gas entrance is arranged in institute It states on washer, the outlet of the purification device is connected with the first entrance.

7. the preparation system of reducing gas for shaft furnace according to claim 6, which is characterized in that

The purification device includes the gas pressurized device and desulfurization and decarburization device being sequentially communicated, the gas pressurized device into Mouth is connected with the washer, and the outlet of the desulfurization and decarburization device is connected with the first entrance.

8. the preparation system of reducing gas for shaft furnace according to any one of claim 1 to 7, which is characterized in that

The preparation system of the reducing gas for shaft furnace further includes shaft furnace, and the shaft furnace includes furnace body, and the furnace body is equipped with iron Ore inlet, top gas outlet, also Primordial Qi entrance and direct reduced iron outlet, the top gas outlet and the top gas entrance It is connected, the also Primordial Qi entrance is connected with the also Primordial Qi outlet, and the direct reduced iron entrance can directly be gone back with described Former iron outlet is connected.