Composite injection device for hydrogen-rich gas fuel and pulverized coal

Abstract

A composite injection device for hydrogen-rich gas fuel and pulverized coal comprises a hydrogen-rich gas fuel header pipe and a nitrogen header pipe, and is characterized in that the hydrogen-rich gas fuel header pipe comprises a first valve bank, a second valve bank and third valve banks, one end of the nitrogen header pipe is connected with a nitrogen source (18), the other end of the nitrogen header pipe sequentially passes through a nitrogen header pipe pneumatic stop valve (12), and in each third valve bank, one end of the nitrogen header pipe is connected with a first valve bank, and the other end of the nitrogen header pipe is connected with a second valve bank. And the injection branch pipe from the hydrogen-rich gas fuel header pipe passes through the pipeline output end of the branch pipe stop valve (8), is converged with the nitrogen injection branch pipe from the nitrogen header pipe passes through the pipeline output end of the nitrogen purging valve (10) and the nitrogen check valve (9), and enters a blast furnace tuyere (19) through a control valve. The composite injection device and method for the hydrogen-rich gas fuel and the pulverized coal have the advantages that the hydrogen reduction proportion of a blast furnace is increased, the indirect reduction efficiency of furnace charge is improved, the direct reduction proportion is reduced, the smelting efficiency of the blast furnace is improved, the CO2 emission is reduced, and low-carbon ironmaking is realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of blast furnace ironmaking, and specifically, it is a composite injection device for hydrogen-rich gas fuel and pulverized coal. Background Art

[0002] With the increasing requirements for environmental protection and ecology in China, as well as the strengthening of control over coal consumption and carbon emissions, especially the strong promotion of ecological environment protection in the Yangtze River Delta region and the Yangtze River Basin, and the implementation of carbon trading and future carbon emission tax collection, coal restriction and carbon reduction have become a huge pressure on the survival and development of urban steel bases at present and in the future, and the situation is urgent.

[0003] The ironmaking process is the main process for coal consumption, energy consumption and CO2 generation in steel plants. The energy consumption and CO2 generation amount account for about 70% of the total amount in the steel production process. The existing blast furnace process is still the mainstream of future ironmaking. Changing the ironmaking energy structure, using clean energy such as natural gas, coke oven gas and hydrogen as reducing agents, including injecting hydrocarbons such as waste plastics, waste tires and biomass to replace coke and pulverized coal, and increasing the proportion of hydrogen reduction in the blast furnace, is one of the ways to control coal and reduce carbon, and is also an effective way that can be implemented in the near future.

[0004] However, the proportion of hydrogen in the reducing gas of the existing hydrogen-rich substances injected into the blast furnace is low, the indirect reduction efficiency of the burden is low, and the direct reduction ratio is high.

[0005] Therefore, the known forms of injecting hydrogen-rich substances into the blast furnace have the above-mentioned various inconveniences and problems. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a safe and reliable composite injection device for hydrogen-rich gas fuel and pulverized coal.

[0007] To achieve the above purpose, the technical solution of the utility model is:

[0008] A composite injection device for hydrogen-rich gas fuel and pulverized coal, including a hydrogen-rich gas fuel main pipe and a nitrogen main pipe, characterized in that:

[0009] The hydrogen-rich gas fuel main pipe includes a first valve group, a second valve group and a third valve group. One end of the first valve group is connected to a hydrogen-rich gas fuel source, and the other end is connected to the second valve group through a relief valve group and a blind plate cut-off valve. The second valve group is sequentially connected to a hydrogen-rich gas fuel injection branch pipe area through a relief valve group, a main pipe flowmeter, a main pipe pneumatic cut-off valve, a main pipe regulating valve, a flowmeter and a flow regulating valve. The hydrogen-rich gas fuel injection branch pipe area is provided with a number of hydrogen-rich gas fuel injection branch pipes, and each hydrogen-rich gas fuel injection branch pipe is connected to enter a third valve group;

[0010] One end of the nitrogen main pipe is connected to a nitrogen source, and the other end is connected to the nitrogen injection branch pipe area through a pneumatic cut-off valve for the nitrogen main pipe, a nitrogen pressure regulating valve, a flow meter for the nitrogen main pipe, a nitrogen regulating valve, and a nitrogen safety valve in sequence. The nitrogen injection branch pipe area is provided with a plurality of nitrogen injection branch pipes, and each nitrogen injection branch pipe is connected to enter a third valve group;

[0011] Wherein: in each of the third valve groups, the output end of the pipe of the injection branch pipe from the hydrogen-rich gas fuel main pipe, after passing through the branch cut-off valve, converges with the output end of the pipe of the nitrogen injection branch pipe from the nitrogen main pipe, which has passed through a nitrogen purge valve and a nitrogen check valve, and enters the blast furnace tuyere through a control valve.

[0012] The composite injection device for hydrogen-rich gas fuel and pulverized coal of the present utility model can also be further realized by adopting the following technical measures.

[0013] For the aforementioned composite injection device for hydrogen-rich gas fuel and pulverized coal, when the nitrogen main pipe is initially used, or has been out of use for a long time and is reused, the gas in the nitrogen main pipe is purged, replaced, and discharged through a relief valve group.

[0014] For the aforementioned composite injection device for hydrogen-rich gas fuel and pulverized coal, the gas source pressure at the outlet end of the main pipe regulating valve is 0.8 - 1.3 MPa.

[0015] For the aforementioned composite injection device for hydrogen-rich gas fuel and pulverized coal, the number of the injection branch pipes is the same as the number of blast furnace tuyeres.

[0016] For the aforementioned composite injection device for hydrogen-rich gas fuel and pulverized coal, the flow meter is set with a set value according to the requirements of the blast furnace.

[0017] For the aforementioned composite injection device for hydrogen-rich gas fuel and pulverized coal, a relief valve group and a manual cut-off valve are respectively provided at the front and rear ends of the pipe of the third valve group in the hydrogen-rich gas fuel main pipe.

[0018] A composite injection method for hydrogen-rich gas fuel and pulverized coal is characterized by including the following steps:

[0019] a. The hydrogen-rich gas fuel suitable for blast furnace injection is regulated to 0.8 - 1.3 MPa and then transported to the vicinity of the blast furnace tuyere through a pipeline. The gas source is required to supply stably, and the pressure is required to be not lower than 0.8 MPa;

[0020] b. The valves provided in the gas fuel transportation main pipe are respectively valve groups A, B, and C. Among them, valve group A is connected to the gas source pipeline. At the interface, a main pipe purge and discharge device is provided. When the pipeline is initially used, or has been out of use for a long time and is reused, the main pipe is purged and the gas is replaced;

[0021] c. The B valve group is equipped with a main pipe cut-off valve, a main pipe flowmeter, a pressure reducing valve, a regulating valve, a manual cut-off valve, and main pipe pressure and temperature measuring instruments. At the same time, a purging and venting device is also set between the valves for use during the replacement operation of the flowmeter and the regulating valve;

[0022] d. The C valve group consists of injection branch cut-off valves and nitrogen purging valves, and the number is equal to the number of blast furnace tuyeres. The injection branch cut-off valves and the nitrogen purging valves are interlocked with each other: during normal injection, the injection branch cut-off valves are open and the nitrogen purging valves are closed. When there is a fault in the injection branch or injection stops, when the injection branch cut-off valves are closed, the nitrogen purging valves are opened to purge and cool the injection branches;

[0023] e. A flexible connection, a manual valve, and a check valve are provided in front of the lance where the injection branch is connected to the tuyere to prevent safety accidents caused by the diversion of high-temperature gas. The lance connected to the tuyere adopts a coaxial lance type with two layers, with pulverized coal flowing through the inner cylinder and gas flowing through the outer cylinder.

[0024] The composite injection method of hydrogen-rich gas fuel and pulverized coal of the present utility model can also be further realized by adopting the following technical measures.

[0025] In the foregoing method, the pressure of the nitrogen source is not less than 0.6 MPa.

[0026] After adopting the above technical solutions, the composite injection device and method of hydrogen-rich gas fuel and pulverized coal of the present utility model have the following advantages:

[0027] 1. Change the ironmaking energy structure, use clean energy such as natural gas, coke oven gas, and hydrogen as reducing agents to replace part of the coke and pulverized coal, increase the hydrogen reduction ratio in the blast furnace, give play to the advantage that the reduction kinetics of H2 is stronger than that of CO at high temperatures, improve the indirect reduction efficiency of the burden, reduce the direct reduction ratio, and improve the blast furnace smelting efficiency;

[0028] 2. Injecting hydrogen-rich gas fuel into the blast furnace can directly replace coke and pulverized coal, reduce the consumption of coke, promote coal saving and carbon reduction in ironmaking production, reduce CO2 emissions, and achieve low-carbon ironmaking. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of the composite injection device for injecting hydrogen-rich gas fuel and pulverized coal into the blast furnace according to the embodiment of the present utility model.

[0030] In the figure: 1 is the vent valve group, 2 is the blind plate cut-off valve, 3 is the main pipe flowmeter, 4 is the main pipe pneumatic cut-off valve, 5 is the main pipe pressure regulating valve, 6 is the flowmeter, 7 is the flow regulating valve, 8 is the branch pipe cut-off valve, 9 is the nitrogen check valve, 10 is the nitrogen purging valve, 11 is the manual cut-off valve, 12 is the nitrogen main pipe pneumatic cut-off valve, 13 is the nitrogen pressure regulating valve, 14 is the nitrogen main pipe flowmeter, 15 is the nitrogen regulating valve, 16 is the nitrogen safety valve, 17 is the hydrogen-rich gas fuel source, 18 is the nitrogen source, 19 is the blast furnace tuyere, 20 is the hydrogen-rich gas fuel injection branch pipe, 21 is the nitrogen injection branch pipe, A is the first valve group, B is the second valve group, and C is the third valve group. Specific embodiments

[0031] The present invention will be further described below in conjunction with embodiments and their accompanying drawings.

[0032] Embodiment 1

[0033] The composite injection device for hydrogen-rich gas fuel and pulverized coal of the present invention includes a hydrogen-rich gas fuel main pipe and a nitrogen main pipe.

[0034] Now please refer to Figure 1 , Figure 1 , which is a schematic structural diagram of the composite injection device for injecting hydrogen-rich gas fuel and pulverized coal into a blast furnace according to an embodiment of the present invention. As shown in the figure, the hydrogen-rich gas fuel main pipe includes a first valve group A, a second valve group B, and a third valve group C. One end of the first valve group is connected to the hydrogen-rich gas fuel source 17, and the other end is connected to the second valve group through the vent valve group 1 and the blind plate cut-off valve 2. The second valve group is sequentially connected to the hydrogen-rich gas fuel injection branch pipe area through the vent valve group 1, the main pipe flowmeter 3, the main pipe pneumatic cut-off valve 4, the main pipe pressure regulating valve 5, the flowmeter 6, and the flow regulating valve 7. The hydrogen-rich gas fuel injection branch pipe area is provided with a plurality of hydrogen-rich gas fuel injection branch pipes 20, and each hydrogen-rich gas fuel injection branch pipe is connected to enter a third valve group;

[0035] One end of the nitrogen main pipe is connected to the nitrogen source 18, and the other end is sequentially connected to the nitrogen injection branch pipe area through the nitrogen main pipe pneumatic cut-off valve 12, the nitrogen pressure regulating valve 13, the nitrogen main pipe flowmeter 14, the nitrogen regulating valve 15, and the nitrogen safety valve 16. The nitrogen injection branch pipe area is provided with a plurality of nitrogen injection branch pipes 21, and each nitrogen injection branch pipe is connected to enter a third valve group;

[0036] Among them: in each of the third valve groups, the injection branch pipe from the hydrogen-rich gas fuel main pipe outputs through the pipeline output end of the branch pipe cut-off valve 8 and converges with the nitrogen injection branch pipe from the nitrogen main pipe through the pipeline output ends of the nitrogen purge valve 10 and the nitrogen check valve 9 and enters the blast furnace tuyere 19 through the control valve. When the nitrogen main pipe is initially used, or has been out of use for a long time and is reused, the gas purge, replacement and discharge of the nitrogen main pipe are carried out through the relief valve group 1. The gas source pressure at the outlet end of the main pipe regulating valve 5 is 1.0 MPa. The number of the injection branch pipes is the same as the number of blast furnace tuyeres. The flowmeter 6 is set with a set value according to the requirements of the blast furnace.

[0037] The composite injection device for injecting hydrogen-rich gas fuel and pulverized coal into a blast furnace according to an embodiment of the present invention further includes a relief valve group 1 and a manual cut-off valve 11 provided at the front and rear ends of the pipeline of the third valve group in the hydrogen-rich gas fuel main pipe.

[0038] Embodiment 2

[0039] The composite injection method for injecting hydrogen-rich gas fuel and pulverized coal into a blast furnace according to an embodiment of the present invention:

[0040] 1) Introduce the hydrogen-rich gas fuel suitable for blast furnace injection from the gas source main pipe, pass through the blind plate cut-off valve 2, and enter the nitrogen main pipe. To ensure safety, when the main pipe is initially used, or has been out of use for a long time and is reused, the gas purge, replacement and discharge of the main pipe are carried out through the relief valve group 1.

[0041] 2) The gas in the main pipe passes through the main pipe flowmeter 3, the main pipe pneumatic cut-off valve 4, and through the main pipe regulating valve 5, and the gas source pressure is adjusted to 0.8 - 1.3 MPa according to the actual production needs.

[0042] The gas injection volume is automatically adjusted according to the set value required by the blast furnace and through the flowmeter 6 and the flow regulating valve 7.

[0043] 3) Injection branch pipes are respectively connected from the nitrogen main pipe, and the number is the same as the number of blast furnace tuyeres. A branch pipe cut-off valve 8 is provided on the injection branch pipe, and a nitrogen purge pipe is connected behind the branch pipe cut-off valve. A nitrogen purge valve 10 and a check valve 9 are provided on the nitrogen purge pipe. Among them, the injection branch pipe cut-off valve 8 and the nitrogen purge valve 10 are interlocked with each other: when injecting normally, the injection branch pipe cut-off valve 8 is opened and the nitrogen purge valve 10 is closed. When the injection branch pipe fails or the injection stops, the injection branch pipe cut-off valve 8 is closed and the nitrogen purge valve 10 is opened to purge and cool the injection branch pipe.

[0044] In addition, when the main pipe pressure is lower than the set value of the blast furnace hot blast pressure, the system automatically closes the injection branch pipe cut-off valve 8 and opens the nitrogen purge valve 10 to ensure the safety of the injection system.

[0045] 4) The hydrogen-rich gas enters the blast furnace tuyere through the injection branch pipe and the tuyere lance, and participates in the reduction reaction of blast furnace smelting as fuel gas. The injection system can conduct gas injection alone or conduct combined injection of pulverized coal-hydrogen-rich gas fuel.

[0046] The utility model has substantial features and remarkable technical progress. The combined injection device and method of hydrogen-rich gas fuel and pulverized coal of the utility model can change the energy structure of blast furnace ironmaking, use the clean energy hydrogen-rich gas fuel as a reducing agent, increase the proportion of hydrogen reduction in the blast furnace, improve the blast furnace smelting efficiency, replace part of the coke and pulverized coal, promote coal saving and carbon reduction in ironmaking production, reduce the CO2 emissions, and realize low-carbon ironmaking.

[0047] The above embodiments are only for illustrating the utility model, rather than limiting the utility model. Those skilled in the relevant technical fields can also make various transformations or changes without departing from the spirit and scope of the utility model. Therefore, all equivalent technical solutions should also fall within the scope of the utility model and should be defined by each claim.

Claims

1. A composite injection device for hydrogen-rich gas fuel and pulverized coal, comprising a hydrogen-rich gas fuel main pipe and a nitrogen main pipe, characterized in that: The hydrogen-rich gas fuel main pipe comprises a first valve group (A), a second valve group (B), and a third valve group (C); one end of the first valve group is connected to a hydrogen-rich gas fuel source (17), and the other end is connected to the second valve group via a relief valve group (1) and a blind plate cut-off valve (2); the second valve group is connected to a hydrogen-rich gas fuel injection branch pipe area via the relief valve group (1), a main pipe flow meter (3), a main pipe pneumatic cut-off valve (4), a main pipe regulating valve (5), a flow meter (6), and a flow regulating valve (7) in sequence; the hydrogen-rich gas fuel injection branch pipe area is provided with a plurality of hydrogen-rich gas fuel injection branch pipes (20), each of which is connected to a third valve group; One end of the nitrogen main pipe is connected to a nitrogen source (18), and the other end is connected to a nitrogen injection branch pipe area through a nitrogen main pipe pneumatic shut-off valve (12), a nitrogen pressure regulating valve (13), a nitrogen main pipe flow meter (14), a nitrogen regulating valve (15), and a nitrogen safety valve (16) in sequence. The nitrogen injection branch pipe area is provided with a plurality of nitrogen injection branch pipes (21), and each nitrogen injection branch pipe is connected to a third valve group; Wherein: in each of the third valve groups, the injection branch pipe from the hydrogen-rich gas fuel main pipe passes through the pipeline output end of the branch pipe cut-off valve (8), and the nitrogen injection branch pipe from the nitrogen main pipe passes through the pipeline output end of the nitrogen purge valve (10) and the nitrogen check valve (9), and enters the blast furnace tuyere (19) through the control valve.

2. The combined injection device of hydrogen-rich gas fuel and pulverized coal according to claim 1, characterized in that: When the nitrogen main pipe is initially used, or is shut down for a long time or reused, the gas in the nitrogen main pipe is purged, replaced and released through the release valve group (1).

3. The combined injection device of hydrogen-rich gas fuel and pulverized coal according to claim 1, characterized in that: The gas source pressure at the outlet of the main pipe regulating valve (5) is 0.8-1.3 MPa.

4. The combined injection device of hydrogen-rich gas fuel and pulverized coal according to claim 1, characterized in that: The number of the injection branch pipes is the same as the number of blast furnace tuyere.

5. The combined injection device of hydrogen-rich gas fuel and pulverized coal according to claim 1, characterized in that: The flow meter (6) is set to a set value according to the requirements of the blast furnace.

6. The combined injection device of hydrogen-rich gas fuel and pulverized coal according to claim 1, characterized in that: It also includes a third valve group pipeline in the hydrogen-rich gas fuel main pipe, the front and rear ends of which are each provided with a relief valve group (1) and a manual shut-off valve (11).

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