Safety isolation device, coal water slurry entrained-flow bed gasification furnace, oxygen introduction control method and deoxygenation control method

Abstract

The invention provides a safety isolation device, a coal water slurry entrained-flow bed gasifier, an oxygen introduction control method and an oxygen removal control method, and relates to the technical field of gasifiers. The safety isolation device comprises a first connecting pipeline and an oxygen emptying branch, one end of the first connecting pipeline is used for being connected with an oxygen supply system, and the other end of the first connecting pipeline is used for being connected with an oxygen removal system; the other end is connected with an oxygen system; and a second stop valve and a first stop valve are sequentially arranged in the conveying direction of the first connecting pipeline. According to the safety isolation device, the second stop valve is arranged in front of the first stop valve used for communicating the multi-nozzle opposed coal water slurry entrained-flow bed gasifier oxygen system and the oxygen public pipe network, and the first oxygen emptying valve is additionally arranged between the first stop valve and the second stop valve; in the maintenance period of the gasification furnace, the first stop valve and the second stop valve are closed, and the first oxygen emptying valve is opened, so that oxygen in the oxygen public pipe network can be prevented from entering an oxygen system of the gasification furnace, and safety accidents are avoided.

Description

Technical Field

[0001] This invention relates to the technical field of gasifiers, and in particular to a safety isolation device, a coal-water slurry gasifier, an oxygen induction control method, and an oxygen deoxygenation control method. Background Technology

[0002] The multi-nozzle opposed-flow coal-water slurry gasifier is currently a relatively mature coal-water slurry gasification technology in China. By opposing nozzles, the multi-nozzle opposed-flow coal-water slurry gasifier creates an impinging flow within the furnace, enhancing mixing and heat and mass transfer processes, and forming a reasonable flow field structure within the furnace. This results in excellent process and engineering effects: high effective gas composition, high carbon conversion rate, and long refractory brick life.

[0003] This unit is a process for producing syngas from pure oxygen and coal / coke slurry. The unit includes a coal / coke slurry conveying unit, a gasification and preliminary purification unit, and a slag and water treatment unit. During normal production, a single furnace can process 2,500 tons of coal per day (nominal capacity); the effective gas output of a single furnace is 140,000 Nm3 / h (CO + H2); one gasifier is in operation and the other is on standby. However, the existing multi-nozzle opposed coal-water slurry gasifier only has one shut-off valve between its oxygen system and the common oxygen pipeline. During maintenance of the multi-nozzle opposed coal-water slurry gasifier, it is necessary to completely isolate the gasifier's oxygen system from the common oxygen pipeline. However, the existing single shut-off valve cannot completely isolate the oxygen system from the common oxygen pipeline, thus posing a safety hazard. Furthermore, each start-up and shutdown requires manual intervention to introduce oxygen to the first oxygen vent valve of the multi-nozzle opposed coal-water slurry gasifier. Summary of the Invention

[0004] The purpose of this invention is to provide a safety isolation device, a coal-water slurry gasifier, an oxygen induction control method, and an oxygen desorption control method to alleviate the technical problem that currently, during the maintenance of a nozzle-opposed coal-water slurry gasifier, it is necessary to completely isolate the oxygen system of the gasifier from the common oxygen pipeline network, but the existing single shut-off valve cannot completely isolate the oxygen system from the common oxygen pipeline network, thus posing a safety hazard.

[0005] The present invention provides a safety isolation device, including a first connecting pipe and an oxygen venting branch, wherein one end of the first connecting pipe is used to connect to an oxygen supply system and the other end is used to connect to an oxygen system. A second shut-off valve and a first shut-off valve are sequentially arranged in the conveying direction of the first connecting pipeline; one end of the oxygen venting branch is connected to the first connecting pipeline, and the connection point between the oxygen venting branch and the first connecting pipeline is located between the first shut-off valve and the second shut-off valve. A first oxygen vent valve is installed on the oxygen vent branch.

[0006] In an optional embodiment, a nitrogen supply pipeline is also included, one end of which is used to connect to the nitrogen supply system, and the other end is used to connect to the first connecting pipeline. Furthermore, the connection point between the nitrogen supply pipeline and the first connecting pipeline is located downstream of the first shut-off valve. In an optional embodiment, a nitrogen filling valve is provided on the nitrogen supply pipeline.

[0007] In an optional embodiment, a control terminal is also included, wherein the first shut-off valve, the second shut-off valve, the first oxygen vent valve, and the nitrogen charging valve are all electrically controlled valves; The control terminal is electrically connected to the first shut-off valve, the second shut-off valve, the first oxygen vent valve, and the nitrogen charging valve, respectively, and is used to control the working state of the first shut-off valve, the second shut-off valve, the first oxygen vent valve, and the nitrogen charging valve to be open or closed.

[0008] In an optional implementation, the first shut-off valve is interlocked with the nitrogen filling valve.

[0009] In an optional embodiment, a first pressure measuring line is further included, both ends of which are connected to the first connecting line. The second shut-off valve is located between the two connections of the first pressure measuring pipeline and the first connecting pipeline; a first differential pressure gauge, a first pressure gauge and a second pressure gauge are provided on the first pressure measuring pipeline, and the first differential pressure gauge is located between the first pressure gauge and the second pressure gauge; the first pressure gauge is used to measure the pressure upstream of the second shut-off valve, and the second pressure gauge is used to measure the pressure downstream of the second shut-off valve. In an optional embodiment, a second pressure measuring line is further included, one end of which is connected to the first connecting line and the other end of which is connected to the first pressure measuring line. The first shut-off valve is located between the connection point of the second pressure measuring pipeline and the first connecting pipeline and the connection point of the first pressure measuring pipeline and the first connecting pipeline; a second differential pressure gauge and a third pressure gauge are installed on the second pressure measuring pipeline; the third pressure gauge is used to measure the pressure downstream of the first shut-off valve.

[0010] The safety isolation device of the present invention, by setting a second shut-off valve before the first shut-off valve used to connect the oxygen system of the multi-nozzle opposed coal-water slurry gasifier and the oxygen common pipeline, and adding a first oxygen vent valve between the first shut-off valve and the second shut-off valve, can prevent oxygen in the oxygen common pipeline from entering the oxygen system of the gasifier and avoid the occurrence of safety accidents by closing the first shut-off valve and the second shut-off valve and opening the first oxygen vent valve during gasifier maintenance.

[0011] This invention provides a coal-water slurry gasifier, including the safety isolation device described in any of the foregoing embodiments; The coal-water slurry gasifier includes a second connecting pipeline, one end of which is connected to the first connecting pipeline; a burner oxygen regulating valve and an oxygen burner shut-off valve are provided in the conveying direction of the second connecting pipeline; a fourth pressure gauge is provided on the second connecting pipeline, and the fourth pressure gauge is located between the burner oxygen regulating valve and the oxygen burner shut-off valve.

[0012] The second connecting pipeline is equipped with a first nitrogen supply pipeline and a high-pressure nitrogen supply pipeline. One end of the first nitrogen supply pipeline is connected to the second connecting pipeline, and the other end is connected to the nitrogen supply system. A burner nitrogen plug valve is installed on the first nitrogen supply pipeline. One end of the high-pressure nitrogen supply pipeline is connected to the second connecting pipeline, and the other end is connected to the high-pressure nitrogen supply system. A high-pressure gauge is installed on the high-pressure nitrogen supply pipeline.

[0013] Compared with the prior art, the water-coal slurry fluidized bed gasifier provided by the present invention has the safety isolation device provided by the present invention, and thus has all the beneficial effects of the safety isolation device provided by the present invention.

[0014] This invention provides a method for oxygen control in a coal-water slurry gasifier, which employs the aforementioned coal-water slurry gasifier. S1, when it is confirmed that the multi-nozzle opposed coal-water slurry gasifier is in a shutdown state, the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa and the second shut-off valve is in a closed state, the first oxygen vent valve and the nitrogen charging valve are closed. S2, after confirming that the first oxygen vent valve and the nitrogen charging valve are closed, the second differential pressure gauge is less than or equal to 0.3 MPa and the common interlock is in normal condition, open the first shut-off valve; S3, after confirming that the first shut-off valve is open, the high pressure gauge is greater than or equal to 8.8 MPa and the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa, open the nitrogen charging valve; S4. When it is confirmed that the reading of the first differential pressure gauge is less than or equal to 0.3 MPa and the reading of the second pressure gauge is greater than or equal to 6.0 MPa, close the nitrogen charging valve. S5. When it is confirmed that the nitrogen charging valve is closed and the reading of the first differential pressure gauge is less than or equal to 0.3 MPa, the second shut-off valve is opened.

[0015] This invention provides a method for deoxygenation control in a coal-water slurry gasifier, which employs the aforementioned coal-water slurry gasifier; the method for deoxygenation control in this coal-water slurry gasifier includes: S1, after confirming that the reading of the first differential pressure gauge is less than or equal to 0.3 MPa, close the second shut-off valve; S2, upon confirming that the second shut-off valve is in the closed state, close the nitrogen charging valve and the burner nitrogen plug valve of the gasifier, open the burner oxygen regulating valve of the gasifier, and set the valve opening of the burner oxygen regulating valve to 10%; S3, when it is confirmed that the nitrogen charging valve is closed, the burner nitrogen plug valve is closed, and the reading of the second differential pressure gauge is less than or equal to 0.3 MPa, open the first shut-off valve and the oxygen burner shut-off valve; S4. When it is confirmed that the first shut-off valve is in the open state and the oxygen burner shut-off valve is in the open state, open the first oxygen vent valve. S5, when it is confirmed that the pressure after the second shut-off valve is less than 0.1 MPa, the pressure after the first shut-off valve is less than 0.1 MPa and the pressure after the oxygen regulating valve is less than 0.1 MPa, the oxygen burner shut-off valve, the first shut-off valve and the burner oxygen regulating valve are closed. S6. After confirming that the oxygen burner shut-off valve is in the closed state, open the burner nitrogen plug valve. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the installation isolation device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a water-gas slurry fluidized bed gasifier provided in an embodiment of the present invention; Figure 3 This is a flowchart of the oxygen control method for a coal-water slurry gasifier provided in an embodiment of the present invention. Figure 4 This is a flowchart of the deoxygenation control method for a coal-water slurry gasifier provided in an embodiment of the present invention.

[0018] Icons: 100 - First connecting pipeline; 200 - Oxygen vent branch; 300 - Nitrogen supply pipeline; 400 - Second shut-off valve; 500 - First shut-off valve; 600 - First differential pressure gauge; 700 - Second differential pressure gauge; 800 - First pressure gauge; 900 - Second pressure gauge; 110 - Third pressure gauge; 120 - Nitrogen charging valve; 130 - First oxygen vent valve; 140 - Second connecting pipeline; 150 - Burner oxygen regulating valve; 160 - Oxygen burner shut-off valve; 170 - Fourth pressure gauge; 180 - First nitrogen supply pipeline; 190 - Burner nitrogen plug valve; 210 - High-pressure nitrogen supply pipeline. Detailed Implementation

[0019] The terms “first,” “second,” “third,” etc., are used only for distinguishing descriptions and do not indicate a sequence number, nor should they be interpreted as indicating or implying relative importance.

[0020] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0021] In the description of this application, it should be noted that the terms "inner", "outer", "left", "right", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] In the description of this application, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” shall be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components.

[0023] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings.

[0024] Example Reference Figure 1 The present invention provides a safety isolation device, including a first connecting pipe 100 and an oxygen venting branch 200, wherein one end of the first connecting pipe 100 is used to connect to an oxygen supply system and the other end is used to connect to an oxygen system. A second shut-off valve 400 and a first shut-off valve 500 are sequentially arranged in the conveying direction of the first connecting pipeline 100; one end of the oxygen venting branch 200 is connected to the first connecting pipeline 100, and the connection between the oxygen venting branch 200 and the first connecting pipeline 100 is located between the first shut-off valve 500 and the second shut-off valve 400. A first oxygen vent valve 130 is provided on the oxygen vent branch 200.

[0025] In some embodiments, one end of the first connecting pipe 100 is connected to an oxygen supply system, and the other end is connected to the oxygen system of a multi-nozzle opposed coal-water slurry gasifier; a second shut-off valve 400 and a first shut-off valve 500 are sequentially arranged in the oxygen delivery direction of the first connecting pipe 100.

[0026] The first shut-off valve 500 and the second shut-off valve 400 are closed during maintenance of the multi-nozzle opposed coal-water slurry gasifier, and the first oxygen vent valve 130 is opened during maintenance of the multi-nozzle opposed coal-water slurry gasifier.

[0027] The safety isolation device includes a second shut-off valve 400 installed before the first shut-off valve 500 used to connect the oxygen system and oxygen supply system of the multi-nozzle opposed coal-water slurry gasifier, and a first oxygen vent valve 130 added between the first shut-off valve 500 and the second shut-off valve 400. During gasifier maintenance, the first shut-off valve 500 and the second shut-off valve 400 are closed, and the first oxygen vent valve 130 is opened. This can prevent oxygen from the common oxygen pipeline from entering the oxygen system of the gasifier and avoid the occurrence of safety accidents.

[0028] The multi-nozzle opposed coal-water slurry gasifier has multiple oxygen systems, each of which is connected to a first shut-off valve 500. Depending on the number of oxygen systems in the multi-nozzle opposed coal-water slurry gasifier, the safety isolation device is equipped with a second shut-off valve 400 and multiple first shut-off valves 500. That is, multiple branch connection pipelines are provided on the first connection pipeline 100, and each branch connection pipeline is equipped with a first shut-off valve 500.

[0029] During the maintenance of a multi-nozzle opposed coal-water slurry gasifier, the first shut-off valve 500 and the second shut-off valve 400 are closed, and the first oxygen vent valve 130 is opened, so that the first connecting pipeline 100 between the first shut-off valve 500 and the second shut-off valve 400 is connected to the atmosphere. Once the oxygen in the oxygen supply system leaks through the second shut-off valve 400, it will be immediately released to the atmosphere, which can prevent the oxygen in the oxygen supply system from entering the oxygen system of the gasifier, and completely isolate the oxygen system of the gasifier from the oxygen supply system to avoid the occurrence of safety accidents.

[0030] In an optional embodiment, a nitrogen supply pipeline 300 is also included, one end of which is used to connect to a nitrogen supply system, and the other end is used to connect to the first connecting pipeline 100. Furthermore, the connection point between the nitrogen supply pipeline 300 and the first connecting pipeline 100 is located downstream of the first shut-off valve 500. In an optional embodiment, a nitrogen filling valve 120 is provided on the nitrogen supply pipeline 300.

[0031] In an optional embodiment, a control terminal is also included, wherein the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen filling valve 120 are all electrically controlled valves. The control terminal is electrically connected to the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen filling valve 120, respectively, and is used to control the working state of the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen filling valve 120 to be open or closed.

[0032] In an optional embodiment, the first shut-off valve 500 is interlocked with the nitrogen filling valve 120.

[0033] In some embodiments, the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen charging valve 120 are all electrically controlled valves; the control terminal can control the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen charging valve 120; and the on / off states of the first shut-off valve 500 and the nitrogen charging valve 120 are always different. When the first shut-off valve 500 is open, the nitrogen charging valve 120 is closed, and when the first shut-off valve 500 is closed, the nitrogen charging valve 120 is open.

[0034] In an optional embodiment, a first pressure measuring line is further included, both ends of which are connected to the first connecting line 100. The second shut-off valve 400 is located between the two connections of the first pressure measuring pipeline and the first connecting pipeline 100; a first differential pressure gauge 600, a first pressure gauge 800, and a second pressure gauge 900 are provided on the first pressure measuring pipeline, and the first differential pressure gauge 600 is located between the first pressure gauge 800 and the second pressure gauge 900; the first pressure gauge 800 is used to measure the pressure upstream of the second shut-off valve 400, and the second pressure gauge 900 is used to measure the pressure downstream of the second shut-off valve 400. Both ends of the first pressure measuring line are connected to the first connecting line 100. The first pressure gauge 800 on the first pressure measuring line is used to measure the pressure upstream of the second shut-off valve 400, the second pressure gauge 900 is used to measure the pressure downstream of the second shut-off valve 400, and the first differential pressure gauge is used to measure the pressure difference between the upstream and downstream of the first shut-off valve 500.

[0035] In an optional embodiment, a second pressure measuring line is further included, one end of which is connected to the first connecting line 100, and the other end is connected to the first pressure measuring line. The first shut-off valve 500 is located between the connection point of the second pressure measuring pipeline and the first connecting pipeline 100 and the connection point of the first pressure measuring pipeline and the first connecting pipeline 100; a second differential pressure gauge 700 and a third pressure gauge 110 are provided on the second pressure measuring pipeline; the third pressure gauge 110 is used to measure the pressure downstream of the first shut-off valve 500.

[0036] One end of the second pressure measuring pipeline is connected to the first connecting pipeline 100, and the other end is connected to the first pressure measuring pipeline. The second pressure measuring pipeline is equipped with a third pressure gauge 110 and a second differential pressure gauge 700. The second pressure gauge 900 measures the downstream pressure of the second shut-off valve 400 and simultaneously measures the upstream pressure of the first shut-off valve 500. The third pressure gauge 110 is used to measure the downstream pressure of the first shut-off valve 500, and the second differential pressure gauge 700 is used to measure the pressure difference between the upstream and downstream of the first shut-off valve 500.

[0037] The safety isolation device of the present invention, by setting a second shut-off valve 400 before the first shut-off valve 500 used to connect the oxygen system of the multi-nozzle opposed coal-water slurry gasifier and the oxygen common pipeline, and adding a first oxygen vent valve 130 between the first shut-off valve 500 and the second shut-off valve 400, can prevent oxygen in the oxygen common pipeline from entering the oxygen system of the gasifier and avoid the occurrence of safety accidents by closing the first shut-off valve 500 and the second shut-off valve 400 and opening the first oxygen vent valve 130 during gasifier maintenance.

[0038] Reference Figure 2 The present invention provides a coal-water slurry gasifier, including the safety isolation device described in any of the foregoing embodiments.

[0039] Compared with the prior art, the water-coal slurry fluidized bed gasifier provided by the present invention has the safety isolation device provided by the present invention, and thus has all the beneficial effects of the safety isolation device provided by the present invention.

[0040] The coal-water slurry fluidized bed gasifier includes a second connecting pipe 140, one end of which is connected to a first connecting pipe 100. A burner oxygen regulating valve 150 and an oxygen burner shut-off valve 160 are provided in the conveying direction of the second connecting pipe 140. A fourth pressure gauge 170 is provided on the second connecting pipe 140, and the fourth pressure gauge 170 is located between the burner oxygen regulating valve 150 and the oxygen burner shut-off valve 160.

[0041] The second connecting pipe 140 is provided with a first nitrogen supply pipe 180 and a high-pressure nitrogen supply pipe 210. One end of the first nitrogen supply pipe 180 is connected to the second connecting pipe 140, and the other end is connected to the nitrogen supply system. A burner nitrogen plug valve 190 is provided on the first nitrogen supply pipe 180. One end of the high-pressure nitrogen supply pipe 210 is connected to the second connecting pipe 140, and the other end is connected to the high-pressure nitrogen supply system. A high-pressure gauge is provided on the high-pressure nitrogen supply pipe 210.

[0042] Reference Figure 3 The present invention provides a method for oxygen control in a coal-water slurry gasification furnace, which uses the coal-water slurry gasification furnace described above. S1, when it is confirmed that the multi-nozzle opposed coal-water slurry gasifier is in a shutdown state, the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa and the second shut-off valve 400 is in a closed state, the first oxygen vent valve 130 and the nitrogen charging valve 120 are closed. S2, when it is confirmed that the first oxygen vent valve 130 and the nitrogen charging valve 120 are closed, the second differential pressure gauge 700 is less than or equal to 0.3 MPa and the common interlock is in normal condition, the first shut-off valve 500 is opened. S3, when it is confirmed that the first shut-off valve 500 is in the open state, the high pressure gauge is greater than or equal to 8.8 MPa and the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa, open the nitrogen charging valve 120; S4. When it is confirmed that the reading of the first differential pressure gauge 600 is less than or equal to 0.3 MPa and the reading of the second pressure gauge 900 is greater than or equal to 6.0 MPa, close the nitrogen charging valve 120. S5. When it is confirmed that the nitrogen charging valve 120 is closed and the reading of the first differential pressure gauge 600 is less than or equal to 0.3 MPa, the second shut-off valve 400 is opened.

[0043] The control terminal also includes an oxygen priming button, which is used to receive an automatic oxygen priming command. The control terminal executes the oxygen priming sequential control logic according to the received automatic oxygen priming command to control the working state of the first shut-off valve 500, the second shut-off valve 400, the first oxygen venting valve 130, and the nitrogen charging valve 120 to be open or closed, so that the multi-nozzle opposed coal-water slurry gasifier can perform oxygen priming operation.

[0044] To prevent cross-contamination between the nitrogen and oxygen systems of a multi-nozzle opposed coal-water slurry gasifier, the process requires the nitrogen charging valve 120 and the first shut-off valve 500 to be interlocked (i.e., the nitrogen charging valve 120 and the first shut-off valve 500 are prohibited from being in the same state). This results in the inability to pressurize the oxygen pipeline between the second shut-off valve 400 and the first shut-off valve 500 after maintenance, while the oxygen shut-off valve is not allowed to open due to high pressure differential, preventing oxygen from being introduced into the gasifier's oxygen pipeline. After the multi-nozzle opposed coal-water slurry gasifier is shut down, the interlock between the first oxygen vent valve 130 and the first shut-off valve 500 prevents the oxygen in the oxygen pipeline after the first shut-off valve 500 from being depressurized and vented. Therefore, this application, through automatic oxygen introduction and deoxygenation sequential control logic, can ensure both safe and complete isolation during gasifier maintenance and safe oxygen introduction and deoxygenation (depressurization and venting).

[0045] Reference Figure 4 This invention provides a method for deoxygenation control in a coal-water slurry gasifier, which employs the aforementioned coal-water slurry gasifier; the method for deoxygenation control in the coal-water slurry gasifier includes: S1, after confirming that the reading of the first differential pressure gauge 600 is less than or equal to 0.3 MPa, close the second shut-off valve 400; S2, when it is confirmed that the second shut-off valve 400 is in the closed state, the nitrogen charging valve 120 and the burner nitrogen plug valve 190 of the gasifier are closed, and the burner oxygen regulating valve 150 of the gasifier is opened, with the valve opening of the burner oxygen regulating valve 150 being 10%; S3, when it is confirmed that the nitrogen charging valve 120 is closed, the burner nitrogen plug valve 190 is closed and the reading of the second differential pressure gauge 700 is less than or equal to 0.3 MPa, the first shut-off valve 500 and the oxygen burner shut-off valve 160 are opened. S4. When it is confirmed that the first shut-off valve 500 is in the open state and the oxygen burner shut-off valve 160 is in the open state, the first oxygen vent valve 130 is opened. S5, when it is confirmed that the pressure after the second shut-off valve 400 is less than 0.1 MPa, the pressure after the first shut-off valve 500 is less than 0.1 MPa and the pressure after the oxygen regulating valve is less than 0.1 MPa, the oxygen burner shut-off valve 160, the first shut-off valve 500 and the burner oxygen regulating valve 150 are closed. S6. After confirming that the oxygen burner shut-off valve 160 is in the closed state, open the burner nitrogen plug valve 190.

[0046] The control terminal also includes a deoxygenation button, which is used to receive an automatic deoxygenation command.

[0047] The control terminal executes deoxygenation sequential control logic according to the received automatic deoxygenation command to control the working state of the first shut-off valve 500, the second shut-off valve 400, the first oxygen vent valve 130, and the nitrogen charging valve 120 to be open or closed, so that the multi-nozzle opposed coal-water slurry gasifier can perform deoxygenation operation.

[0048] If the automatic deoxygenation command has not completed the deoxygenation sequence control logic within the second preset time period after the deoxygenation button is pressed (after activation), the control terminal will control the multi-nozzle opposed coal-water slurry gasifier to return to the initial state; specifically, within 100 minutes of the second preset time period.

[0049] When introducing oxygen in a multi-nozzle opposed coal-water slurry gasifier, the operator only needs to press the oxygen introduction button, and the system will automatically complete the oxygen introduction; when deoxygenating (depressurizing and venting), the operator only needs to press the deoxygenation button, and the system will automatically complete the deoxygenation, avoiding human intervention in the gasifier interlock and manual operation of valves, thus achieving inherent safety.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A safety isolation device, characterized in that, It includes a first connecting pipe (100) and an oxygen venting branch (200), one end of the first connecting pipe (100) is used to connect to the oxygen supply system, and the other end is used to connect to the oxygen system; A second shut-off valve (400) and a first shut-off valve (500) are sequentially arranged in the conveying direction of the first connecting pipeline (100); one end of the oxygen venting branch (200) is connected to the first connecting pipeline (100), and the connection between the oxygen venting branch (200) and the first connecting pipeline (100) is located between the first shut-off valve (500) and the second shut-off valve (400); A first oxygen vent valve (130) is provided on the oxygen vent branch (200).

2. The safety isolation device according to claim 1, characterized in that, It also includes a nitrogen supply pipeline (300), one end of which is used to connect to the nitrogen supply system, and the other end is used to connect to the first connecting pipeline (100); Furthermore, the connection point between the nitrogen supply pipeline (300) and the first connecting pipeline (100) is located downstream of the first shut-off valve (500).

3. The safety isolation device according to claim 2, characterized in that, A nitrogen filling valve (120) is installed on the nitrogen supply pipeline (300).

4. The safety isolation device according to claim 3, characterized in that, It also includes a control terminal, wherein the first shut-off valve (500), the second shut-off valve (400), the first oxygen vent valve (130) and the nitrogen filling valve (120) are all electrically controlled valves; The control terminal is electrically connected to the first shut-off valve (500), the second shut-off valve (400), the first oxygen vent valve (130), and the nitrogen filling valve (120) respectively, and is used to control the working state of the first shut-off valve (500), the second shut-off valve (400), the first oxygen vent valve (130), and the nitrogen filling valve (120) to be open or closed respectively.

5. The safety isolation device according to claim 4, characterized in that, The first shut-off valve (500) is interlocked with the nitrogen filling valve (120).

6. The safety isolation device according to claim 1, characterized in that, It also includes a first pressure measuring line, both ends of which are connected to the first connecting line (100); The second shut-off valve (400) is located between the two connections of the first pressure measuring pipeline and the first connecting pipeline (100); a first differential pressure gauge (600), a first pressure gauge (800) and a second pressure gauge (900) are provided on the first pressure measuring pipeline, and the first differential pressure gauge (600) is located between the first pressure gauge (800) and the second pressure gauge (900); the first pressure gauge (800) is used to measure the pressure upstream of the second shut-off valve (400), and the second pressure gauge (900) is used to measure the pressure downstream of the second shut-off valve (400).

7. The safety isolation device according to claim 1, characterized in that, It also includes a second pressure measuring line, one end of which is connected to the first connecting line (100), and the other end of which is connected to the first pressure measuring line; The first shut-off valve (500) is located between the connection point of the second pressure measuring line and the first connecting line (100) and the connection point of the first pressure measuring line and the first connecting line (100); a second differential pressure gauge (700) and a third pressure gauge (110) are provided on the second pressure measuring line; the third pressure gauge (110) is used to measure the pressure downstream of the first shut-off valve (500).

8. A coal-water slurry fluidized bed gasifier, characterized in that, Includes the security isolation device as described in any one of claims 1-7; The coal-water slurry gasifier includes a second connecting pipe (140), one end of which is connected to a first connecting pipe (100); a burner oxygen regulating valve (150) and an oxygen burner shut-off valve (160) are provided in the conveying direction of the second connecting pipe (140); a fourth pressure gauge (170) is provided on the second connecting pipe (140), and the fourth pressure gauge (170) is located between the burner oxygen regulating valve (150) and the oxygen burner shut-off valve (160); The second connecting pipe (140) is provided with a first nitrogen supply pipe (180) and a high-pressure nitrogen supply pipe (210). One end of the first nitrogen supply pipe (180) is connected to the second connecting pipe (140), and the other end is connected to the nitrogen supply system. A burner nitrogen plug valve (190) is provided on the first nitrogen supply pipe (180). One end of the high-pressure nitrogen supply pipe (210) is connected to the second connecting pipe (140), and the other end is connected to the high-pressure nitrogen supply system. A high-pressure gauge is provided on the high-pressure nitrogen supply pipe (210).

9. A method for controlling oxygen introduction in a coal-water slurry gasifier, characterized in that, It employs the water-coal slurry fluidized bed gasifier as described in claim 8; S1, when it is confirmed that the multi-nozzle opposed coal-water slurry gasifier is in a shutdown state, the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa and the second shut-off valve (400) is in a closed state, the first oxygen vent valve (130) and the nitrogen charging valve (120) are closed. S2, when it is confirmed that the first oxygen vent valve (130) and the nitrogen charging valve (120) are closed, the second differential pressure gauge (700) is less than or equal to 0.3 MPa and the common interlock is in normal condition, the first shut-off valve (500) is opened. S3. When it is confirmed that the first shut-off valve (500) is in the open state, the high pressure gauge is greater than or equal to 8.8 MPa and the nitrogen pressure of the nitrogen supply system is greater than or equal to 6.8 MPa, the nitrogen charging valve (120) is opened. S4. When it is confirmed that the reading of the first differential pressure gauge (600) is less than or equal to 0.3 MPa and the reading of the second pressure gauge (900) is greater than or equal to 6.0 MPa, close the nitrogen charging valve (120). S5. When it is confirmed that the nitrogen charging valve (120) is closed and the reading of the first differential pressure gauge (600) is less than or equal to 0.3 MPa, the second shut-off valve (400) is opened.

10. A method for deoxygenation control in a coal-water slurry gasifier, characterized in that, It employs the coal-water slurry gasifier as described in claim 8; the deoxygenation control method for the coal-water slurry gasifier includes: S1, after confirming that the reading of the first differential pressure gauge (600) is less than or equal to 0.3 MPa, close the second shut-off valve (400). S2, when it is confirmed that the second shut-off valve (400) is in the closed state, the nitrogen charging valve (120) and the burner nitrogen plug valve (190) of the gasifier are closed, and the burner oxygen regulating valve (150) of the gasifier is opened, and the valve opening of the burner oxygen regulating valve (150) is 10%; S3, when it is confirmed that the nitrogen charging valve (120) is closed, the burner nitrogen plug valve (190) is closed and the reading of the second differential pressure gauge (700) is less than or equal to 0.3 MPa, the first shut-off valve (500) and the oxygen burner shut-off valve (160) are opened. S4. When it is confirmed that the first shut-off valve (500) is in the open state and the oxygen burner shut-off valve (160) is in the open state, the first oxygen vent valve (130) is opened. S5, when it is confirmed that the pressure after the second shut-off valve (400) is less than 0.1 MPa, the pressure after the first shut-off valve (500) is less than 0.1 MPa and the pressure after the oxygen regulating valve is less than 0.1 MPa, the oxygen burner shut-off valve (160), the first shut-off valve (500) and the burner oxygen regulating valve (150) are closed. S6. When it is confirmed that the oxygen burner shut-off valve (160) is closed, open the burner nitrogen plug valve (190).

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