A crude gas washing and dust removing system

Abstract

The utility model provides a kind of crude coal gas washing dust removal system, including BGL gasifier, venturi scrubber, coal gas water system, washing separator, heat exchanger, shift converter, waste heat boiler, control valve, temperature sensor, temperature transmitter, PID regulator and controller;The crude gas temperature collected is compared with the set temperature by PID regulator, and the corresponding control signal quantity is output, so as to adjust the opening of control valve, so as to ensure that the crude gas temperature after heat exchange is stable in the range of 230-240 DEG C, ensure that tar, phenolic and the like remain gaseous, avoid condensation, so that coal dust exists in the state of "dry particles", facilitating subsequent dust removal tank efficient capture.

Description

Technical Field

[0001] This utility model relates to the field of BB (Gas Fiber) technology, specifically to a crude gas scrubbing and dust removal system. Background Technology

[0002] The BGL gasifier is a moving bed pressurized gasifier. During operation, a large amount of lignite powder is carried out of the gasifier by the produced crude gas. After being washed by a gasification Venturi scrubber to remove a large amount of dust from the gas, it is sent to a heat exchanger for heat exchange, and finally sent to a shift converter. In the shift converter, the catalyst causes the carbon monoxide in the crude gas to undergo a shift reaction with water vapor to produce hydrogen and carbon dioxide, providing the required raw material hydrogen for the ammonia synthesis unit.

[0003] The current problem is that during the heat exchange process, the raw coal gas contains a large amount of heavy organic matter such as tar, phenols, and naphthalene produced by coal pyrolysis. If the raw coal gas temperature is below 230℃ (which is lower than the dew point of the heavy organic matter), the tar and phenols will condense into liquid and adhere to the surface of coal dust particles, forming an "oil-dust mixture" that can clog the conveying pipeline. If the raw coal gas temperature is above 240℃, it will significantly increase the load on the subsequent cooling system (such as the heat exchanger), requiring additional cooling water or refrigerant to lower the temperature, leading to increased energy consumption.

[0004] If the temperature is controlled at 230-240℃, which is higher than the dew point of heavy organic matter (200-220℃), it can ensure that tar, phenols, etc. remain in a gaseous state and avoid condensation, so that coal dust exists in the state of "dry particles", which is convenient for subsequent dust removal equipment (such as dust removal tank) to collect efficiently. Utility Model Content

[0005] The purpose of this invention is to provide a crude coal gas scrubbing and dust removal system.

[0006] This utility model is implemented by the following technical solution: A crude gas scrubbing and dust removal system includes a BGL gasifier, a Venturi scrubber, a gas-water system, a scrubbing separator, a heat exchanger, a converter, a waste heat boiler, control valves, temperature sensors, temperature transmitters, a PID controller, and a controller. The crude gas outlet of the BGL gasifier is connected to the inlet of the Venturi scrubber. The water inlet of the Venturi scrubber is connected to the high-pressure water outlet of the gas-water system. The outlet of the Venturi scrubber is connected to the inlet of the scrubbing separator. The outlet of the scrubbing separator is connected to the inlet of the heat exchanger via a first pipeline. The shift gas outlet of the shift furnace is connected to the inlet of the waste heat boiler. The outlet of the waste heat boiler is connected to the heat medium inlet of the heat exchanger. The heat medium outlet of the heat exchanger is connected to the inlet of the cooler via a second pipeline. Control valves are installed on both the first and second pipelines. The outlet of the heat exchanger is connected to the inlet of the dust removal tank via a third pipeline. A temperature sensor is installed on the third pipeline. The signal output of the temperature sensor is connected to a temperature transmitter. The signal output of the temperature transmitter is connected to a PID controller. The signal output of the PID controller is connected to a controller. The signal output of the controller is connected to the actuator of the control valve.

[0007] The advantages of this invention are: by comparing the collected crude gas temperature with the set temperature through a PID controller, the corresponding control signal is output to adjust the opening of the control valve, thereby ensuring that the temperature of the crude gas after heat exchange is stable within the range of 230-240℃, ensuring that tar, phenols, etc. remain in a gaseous state and avoid condensation, so that the coal dust exists in a "dry particle" state, which is convenient for efficient collection in the subsequent dust removal tank. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the system structure of this utility model; Figure 2 It is a control flow diagram.

[0009] In the diagram: 1. BGL gasifier, 2. Venturi scrubber, 3. Gas-water system, 4. Scrubber separator, 5. First pipeline, 6. Heat exchanger, 7. Shift converter, 8. Waste heat boiler, 9. Second pipeline, 10. Cooler, 11. Control valve, 12. Third pipeline, 13. Dust removal tank, 14. Temperature sensor, 15. Temperature transmitter, 16. PID controller, 17. Controller. Detailed Implementation

[0010] like Figures 1 to 2 As shown, a crude gas scrubbing and dust removal system includes a BGL gasifier 1, a Venturi scrubber 2, a gas-water system 3, a scrubbing separator 4, a heat exchanger 6, a converter 7, a waste heat boiler 8, a control valve 11, a temperature sensor 14, a temperature transmitter 15, a PID controller 16, and a controller 17. The crude gas outlet of BGL gasifier 1 is connected to the air inlet of Venturi scrubber 2. The water inlet of Venturi scrubber 2 is connected to the high-pressure water outlet of gas-water system 3. The outlet of Venturi scrubber 2 is connected to the inlet of scrubbing separator 4. The gas outlet of scrubbing separator 4 is connected to the air inlet of heat exchanger 6 through first pipeline 5. The gas outlet of converter 7 is connected to the air inlet of waste heat boiler 8. The gas outlet of waste heat boiler 8 is connected to the heat medium inlet of heat exchanger 6. The heat medium outlet of heat exchanger 6 is connected to the inlet of cooler 10 through second pipeline 9. Control valves 11 are installed on both first pipeline 5 and second pipeline 9. The gas outlet of heat exchanger 6 is connected to the inlet of dust removal tank 13 through third pipeline 12. A temperature sensor 14 is installed on the third pipeline 12 to sense the temperature of the crude gas inside the third pipeline 12. The signal output terminal of the temperature sensor 14 is connected to a temperature transmitter 15. The temperature transmitter 15 receives the signal from the temperature sensor 14, converts it to an AD converter, and outputs the signal. The signal output terminal of the temperature transmitter 15 is connected to a PID controller 16 to receive the signal from the temperature transmitter 15. The signal output terminal of the PID controller 16 is connected to a controller 17. The signal output terminal of the controller 17 is connected to the actuator of the control valve 11. The controller 17 receives the signal from the PID controller 16, converts it to an A / D converter, and then controls the opening degree of the actuator of the control valve 11. After calculation and acquisition, the PID controller 16 compares the collected data with the set temperature and outputs a corresponding control signal. When the temperature detected by the temperature sensor 14 is greater than 240℃, the opening of the control valve 11 decreases; when the temperature detected by the temperature sensor 14 is less than 230℃, the opening of the control valve 11 increases. This ensures that the temperature of the raw coal gas after heat exchange is stable within the range of 230-240℃, ensuring that tar, phenols, etc. remain in a gaseous state and avoid condensation, so that the coal dust exists in a "dry particle" state, which is convenient for efficient collection in the subsequent dust removal tank 13.

[0011] The crude coal gas discharged from the BGL gasifier 1 is sent to the Venturi scrubber 2 for washing. A large amount of coal dust in the crude coal gas is removed by gas-water separation. The mud-water mixture discharged from the Venturi scrubber 2 is sent to the scrubbing separator 4 for gas-liquid separation. The mixed liquid at the bottom of the scrubbing separator 4 is sent to the gas-water system 3 for purification after separation. The crude coal gas discharged from the top of the scrubbing separator 4 is sent to the heat exchanger 6 through the first pipeline 5 to exchange heat with the shift gas. The crude coal gas after heat exchange is sent to the dust removal tank 13 to remove coal dust, tar and other impurities in the crude coal gas again, reducing the impurity content in the crude coal gas.

[0012] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A crude gas washing and dust removing system, characterized in that, Includes BGL gasifier (1), Venturi scrubber (2), gas-water system (3), scrubber separator (4), heat exchanger (6), converter (7), waste heat boiler (8), control valve (11), temperature sensor (14), temperature transmitter (15), PID controller (16) and controller (17). The crude gas outlet of the BGL gasifier (1) is connected to the inlet of the Venturi scrubber (2), the water inlet of the Venturi scrubber (2) is connected to the high-pressure outlet of the gas-water system (3), the outlet of the Venturi scrubber (2) is connected to the inlet of the scrubbing separator (4), the outlet of the scrubbing separator (4) is connected to the inlet of the heat exchanger (6) via the first pipeline (5), the shift gas outlet of the shift furnace (7) is connected to the inlet of the waste heat boiler (8), the outlet of the waste heat boiler (8) is connected to the heat medium inlet of the heat exchanger (6), and the heat medium outlet of the heat exchanger (6) is connected to the cooling system via the second pipeline (9). The inlet connection of the device (10) is provided. Control valves (11) are installed on the first pipeline (5) and the second pipeline (9). The outlet of the heat exchanger (6) is connected to the inlet of the dust removal tank (13) through the third pipeline (12). A temperature sensor (14) is installed on the third pipeline (12). The signal output of the temperature sensor (14) is connected to the temperature transmitter (15). The signal output of the temperature transmitter (15) is connected to the PID controller (16). The signal output of the PID controller (16) is connected to the controller (17). The signal output of the controller (17) is connected to the actuator of the control valve (11).

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