Abnormal rapid shutdown of a lock hopper system of a coal gasifier

Abstract

The abnormal rapid shutdown's coal gasification furnace lock hopper system belongs to the technical field of lock hopper control of coal gasification furnace, and comprises a lock hopper, a gasification furnace, a lock hopper circulating pump, a lock hopper flushing water tank, a slag pool and pressure charging water, and a plurality of valves and a controller, the controller is connected with a time monitoring module and a pressure monitoring module, the time monitoring module comprises an NE555 timer, the pressure monitoring module comprises an MPM280 pressure sensor, an LM358 amplifier and an LM339 voltage comparator which are connected in sequence, the valves comprise a lock hopper inlet valve, a lock hopper pressure relief valve, a lock hopper flushing water valve, a lock hopper outlet valve, a lock hopper circulating pump inlet valve and a lock hopper pressure charging valve, the lock hopper pressure relief valve is electrically connected with the timer, rapid response and accurate control are realized through a hardware circuit, abnormal interlocking parking of the gasification furnace is effectively avoided, and the system safety and stability are improved.

Description

Technical Field

[0001] This utility model belongs to the field of coal gasification furnace lock hopper control technology, specifically relating to a coal gasification furnace lock hopper system for abnormally rapid shutdown. Background Technology

[0002] The lock hopper system of a coal gasifier generally adopts a four-step sequential control logic of pressure relief, ash discharge, pressurization, and ash collection. The specific process is as follows: after ash collection in the lock hopper, the inlet valve and the circulating pump inlet valve are closed to disconnect from the gasifier. Then, the pressure in the lock hopper is reduced to below 0.3 MPa through the pressure relief valve. Next, the flushing water valve and the outlet valve are opened for ash discharge. After completion, the relevant valves are closed and the system is pressurized until the pressure difference with the gasifier is less than 0.3 MPa. Finally, the inlet valve and the circulating pump inlet valve are reopened to resume ash collection. However, the lock hopper valves operate in harsh environments, have a high failure rate, and are prone to internal leakage or abnormal valve position feedback, leading to high-pressure gas or liquid entering the low-pressure area. If the lock hopper sequential control logic does not respond in time, the system must wait for a timeout (e.g., 300 seconds) before triggering a stop. However, by this time, the gasifier may have already shut down due to low liquid level, resulting in serious economic losses. Existing technologies lack real-time monitoring and rapid emergency response mechanisms for valve internal leakage, and cannot promptly identify abnormalities through pressure changes during the depressurization phase. There is an urgent need for a locking hopper system that can quickly identify and respond to valve internal leakage to ensure the safe operation of the gasifier.

[0003] The existing technology, disclosed in CN202493744U, describes a control device for the slag-water circulation system between a gasifier and a lock hopper. This device uses a DCS system and a two-position three-way solenoid valve to control the opening and closing of the lock hopper circulation pump inlet valve and the circulation valve, achieving valve interlocking. Its core principle is to use the solenoid valve to switch the gas path, ensuring the interlocking of the two valves, reducing human error, and improving system reliability. However, it still has significant shortcomings in monitoring and responding to slowed pressure relief caused by valve leakage or abnormal feedback. When the valve is not actually closed, the system still relies on the original sequential control logic, failing to quickly identify abnormalities and trigger protective actions during the pressure relief phase, posing a risk of gasifier shutdown due to high-pressure-to-low-pressure interconnection. Utility Model Content

[0004] The technical problem solved by this utility model is to overcome the defects in the existing technology and provide a coal gasification furnace lock hopper system that can shut down abnormally quickly.

[0005] The technical solution adopted in this utility model is as follows:

[0006] The coal gasifier lock hopper system for abnormal rapid shutdown described in this utility model includes a lock hopper and a gasifier. The lock hopper is connected to the gasifier, and the lock hopper is also connected to a lock hopper circulation pump, a lock hopper flushing water tank, a slag pool, and pressurizing water. The lock hopper circulation pump is connected to the gasifier. It also includes a controller, a time monitoring module, a pressure monitoring module, and several valves. The time monitoring module includes a timer, and the pressure monitoring module includes a pressure sensor, an amplifier, and a voltage comparator. The time monitoring module, pressure sensor, and valves are all electrically connected to the controller.

[0007] A slag collection pipe is provided between the lock hopper and the gasifier. Circulation pipes are provided between the lock hopper and the lock hopper circulation pump, and between the lock hopper circulation pump and the gasifier. A pressure relief pipe and a flushing pipe are provided between the lock hopper and the lock hopper flushing water tank, respectively. A slag discharge pipe is provided between the lock hopper and the slag pool, and a pressurization pipe is provided between the lock hopper and the pressurized water.

[0008] The valves include the hopper inlet valve, hopper pressure relief valve, hopper flushing water valve, hopper outlet valve, hopper circulation pump inlet valve, and hopper pressurizing valve.

[0009] The lock hopper inlet valve is located on the slag collection pipe, the lock hopper pressure relief valve is located on the pressure relief pipe, the lock hopper flushing water valve is located on the flushing pipe, the lock hopper outlet valve is located on the slag discharge pipe, the lock hopper circulation pump inlet valve is located on the circulation pipe between the lock hopper and the lock hopper circulation pump, and the lock hopper pressurization valve is located on the pressurization pipe.

[0010] The pressure sensor is located inside the lock bucket. The timer is electrically connected to the lock bucket pressure relief valve. The pressure sensor is electrically connected to the amplifier. The amplifier is electrically connected to the voltage comparator.

[0011] The controller includes a PLC controller and a logic AND gate controller. The logic AND gate controller is a 74LS08 AND gate controller. The logic AND gate controller is electrically connected to the timer and voltage comparator respectively. The lock bucket inlet valve, lock bucket pressure relief valve, lock bucket flushing water valve, lock bucket outlet valve, lock bucket circulation pump inlet valve and lock bucket pressurization valve are all electrically connected to the PLC controller.

[0012] The lock hopper circulation pump is connected to drive motor I, the lock hopper flushing water tank is connected to water pump ATM, and drive motor II is installed at the outlet of the gasifier.

[0013] The timer is an NE555 timer, the pressure sensor is an MPM280 pressure sensor, the amplifier is an LM358 amplifier, and the voltage comparator is an LM339 voltage comparator.

[0014] This utility model has the following beneficial effects:

[0015] 1. The time monitoring module and pressure monitoring module can monitor the pressure operation status of the lock hopper system in real time, effectively avoiding interlock shutdown due to abnormal gasifier pressure, and significantly reducing the risk of unplanned shutdown.

[0016] 2. The pressure monitoring module monitors the pressure inside the lock bucket in real time, ensuring the accuracy and reliability of pressure monitoring and enabling timely detection of abnormalities during the pressure relief process.

[0017] 3. The AND gate controller performs logical judgments on the output signals of the time monitoring module and the pressure monitoring module to ensure that the system quickly returns to a safe state under abnormal conditions and avoids secondary accidents.

[0018] 4. The hardware circuitry enables rapid response and precise control, avoiding delays and complexity, and enhancing the accuracy of status monitoring.

[0019] 5. The system responds quickly and effectively avoids gasifier interlock shutdown caused by high pressure falling into low pressure, ensuring safe operation of the unit and reducing economic losses caused by unplanned shutdowns. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the system of this utility model;

[0021] Figure 2 Circuit diagram of the time monitoring module;

[0022] Figure 3 This is the circuit diagram for the pressure monitoring module;

[0023] Figure 4 This is a block diagram of the electrical connection of this utility model.

[0024] The components are: 1. Lock hopper; 2. Gasifier; 3. Lock hopper circulating pump; 4. Lock hopper flushing water tank; 5. Slag pool; 6. Pressurizing water; 7. Lock hopper inlet valve; 8. Lock hopper pressure relief valve; 9. Lock hopper flushing water valve; 10. Lock hopper outlet valve; 11. Lock hopper circulating pump inlet valve; 12. Lock hopper pressurizing valve; 13. Drive motor I; 14. Water pump ATM; 15. Drive motor II. Detailed Implementation

[0025] like Figures 1 to 2 As shown, the coal gasifier lock hopper system for abnormal rapid shutdown described in this utility model includes a lock hopper 1 and a gasifier 2. The lock hopper 1 is connected to the gasifier 2. The lock hopper 1 is also connected to a lock hopper circulation pump 3, a lock hopper flushing water tank 4, a slag pool 5, and a pressurizing water 6. The lock hopper circulation pump 3 is connected to the gasifier 2. It also includes a controller, a time monitoring module, a pressure monitoring module, and several valves. The time monitoring module includes a timer, and the pressure monitoring module includes a pressure sensor, an amplifier, and a voltage comparator. The time monitoring module, the pressure sensor, and the valves are all electrically connected to the controller.

[0026] A slag collection pipe is provided between lock hopper 1 and gasifier 2. Circulation pipes are provided between lock hopper 1 and lock hopper circulation pump 3, and between lock hopper circulation pump 3 and gasifier 2. A pressure relief pipe and a flushing pipe are provided between lock hopper 1 and lock hopper flushing water tank 4, respectively. A slag discharge pipe is provided between lock hopper 1 and slag pool 5. A pressurization pipe is provided between lock hopper 1 and pressurized water 6.

[0027] The valves include a lock bucket inlet valve 7, a lock bucket pressure relief valve 8, a lock bucket flushing water valve 9, a lock bucket outlet valve 10, a lock bucket circulation pump inlet valve 11, and a lock bucket pressurizing valve 12.

[0028] The lock bucket inlet valve 7 is installed on the slag collection pipe, the lock bucket pressure relief valve 8 is installed on the pressure relief pipe, the lock bucket flushing water valve 9 is installed on the flushing pipe, the lock bucket outlet valve 10 is installed on the slag discharge pipe, the lock bucket circulation pump inlet valve 11 is installed on the circulation pipe between lock bucket 1 and lock bucket circulation pump 3, and the lock bucket pressurization valve 12 is installed on the pressurization pipe.

[0029] The pressure sensor is located inside the lock bucket 1. The timer is electrically connected to the lock bucket pressure relief valve 8. The pressure sensor is electrically connected to the amplifier. The amplifier is electrically connected to the voltage comparator.

[0030] The controller includes a PLC controller and a logic AND gate controller. The logic AND gate controller is a 74LS08 AND gate controller. The logic AND gate controller is electrically connected to the timer and the voltage comparator respectively. The lock bucket inlet valve 7, lock bucket pressure relief valve 8, lock bucket flushing water valve 9, lock bucket outlet valve 10, lock bucket circulation pump inlet valve 11, and lock bucket pressurization valve 12 are all electrically connected to the PLC controller.

[0031] The lock bucket circulation pump 3 is connected to a drive motor I13, the lock bucket flushing water tank 4 is connected to a water pump ATM14, and the gasifier 2 is equipped with a drive motor II 15 at its outlet.

[0032] The timer is an NE555 timer, the pressure sensor is an MPM280 pressure sensor, the amplifier is an LM358 amplifier, and the voltage comparator is an LM339 voltage comparator.

[0033] Specifically, the lock hopper system includes lock hopper 1, gasifier 2, lock hopper circulation pump 3, lock hopper flushing water tank 4, slag pool 5, and pressurizing water 6. Gasifier 2 is connected to lock hopper 1 through a slag collection pipe. Lock hopper 1 is connected to slag pool 5 through a slag discharge pipe. Lock hopper 1 is connected to lock hopper circulation pump 3 through a circulation pipe. Lock hopper circulation pump 3 is then connected back to gasifier 2. Lock hopper 1 is connected to lock hopper flushing water tank 4 through a pressure relief pipe. Lock hopper flushing water tank 4 is then connected back to lock hopper 1. Lock hopper 1 is connected to pressurizing water 6 through a pressurizing pipe. The system also includes an NE555 timer, an MPM280 pressure sensor, an LM358 amplifier, an LM339 voltage comparator, a 74LS08 AND gate controller, and a PLC controller. The MPM280 pressure sensor, LM358 amplifier, and LM339 voltage comparator are connected in sequence. The NE555 timer and LM339 voltage comparator are both electrically connected to the 74LS08 AND gate controller. The 74LS08 AND gate controller is electrically connected to the PLC controller.

[0034] Specifically, after the slag collection in lock hopper 1 is completed, the PLC controller closes the lock hopper inlet valve 7 and the lock hopper circulation pump inlet valve 11, disconnecting lock hopper 1 from gasifier 2, and then opens the lock hopper pressure relief valve 8 to begin depressurization. At this time, the NE555 timer starts, and the MPM280 pressure sensor monitors the pressure inside lock hopper 1 in real time. When the pressure inside lock hopper 1 is not abnormal, the PLC controller continues to execute the subsequent slag discharge operation, opening the lock hopper flushing water valve 9 and the lock hopper outlet valve 10 in sequence to discharge slag. After the slag discharge is completed, the relevant valves are closed and the lock hopper pressurization valve 12 is started to equalize the pressure until the pressure difference between lock hopper 1 and gasifier 2 is normal. Then the lock hopper pressurization valve 12 is closed, and finally the lock hopper inlet valve 7 and the lock hopper circulation pump inlet valve 11 are reopened to resume slag collection.

[0035] Specifically, during the depressurization process, when the pressure inside the lock hopper 1 becomes abnormal, it indicates that there is internal leakage or incomplete closure of the lock hopper inlet valve 7 or the lock hopper circulation pump inlet valve 11. At this time, an abnormal response is triggered, and the PLC controller immediately closes the lock hopper pressure relief valve 8, the lock hopper flushing water valve 9, and the lock hopper outlet valve 10, stops the depressurization and slag discharge operations, and opens the lock hopper pressurization valve 12 to quickly equalize the pressure between the lock hopper 1 and the gasifier 2 to a balanced state, avoiding the interlocking shutdown of the gasifier 2 due to high pressure leading to low pressure, and ensuring the safe operation of the unit.

Claims

1. A coal gasifier lock hopper system for abnormally rapid shutdown, comprising a lock hopper (1) and a gasifier (2), wherein the lock hopper (1) is connected to the gasifier (2), characterized in that, The lock hopper (1) is also connected to a lock hopper circulation pump (3), a lock hopper flushing water tank (4), a slag pool (5), and pressurized water (6), respectively. The lock hopper circulation pump (3) is connected to the gasifier (2). It also includes a controller, a time monitoring module, a pressure monitoring module, and several valves. The time monitoring module includes a timer, and the pressure monitoring module includes a pressure sensor, an amplifier, and a voltage comparator. The time monitoring module, the pressure sensor, and the valves are all electrically connected to the controller.

2. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 1, characterized in that, A slag collection pipe is provided between the lock hopper (1) and the gasifier (2). A circulation pipe is provided between the lock hopper (1) and the lock hopper circulation pump (3), and between the lock hopper circulation pump (3) and the gasifier (2). A pressure relief pipe and a flushing pipe are provided between the lock hopper (1) and the lock hopper flushing water tank (4). A slag discharge pipe is provided between the lock hopper (1) and the slag pool (5). A pressurization pipe is provided between the lock hopper (1) and the pressurized water (6).

3. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 2, characterized in that, The valves include a lock bucket inlet valve (7), a lock bucket pressure relief valve (8), a lock bucket flushing water valve (9), a lock bucket outlet valve (10), a lock bucket circulation pump inlet valve (11), and a lock bucket pressurizing valve (12).

4. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 3, characterized in that, The lock bucket inlet valve (7) is installed on the slag collection pipe, the lock bucket pressure relief valve (8) is installed on the pressure relief pipe, the lock bucket flushing water valve (9) is installed on the flushing pipe, the lock bucket outlet valve (10) is installed on the slag discharge pipe, the lock bucket circulation pump inlet valve (11) is installed on the circulation pipe between the lock bucket (1) and the lock bucket circulation pump (3), and the lock bucket pressurization valve (12) is installed on the pressurization pipe.

5. The coal gasifier lock hopper system for abnormal rapid shutdown according to claim 4, characterized in that, The pressure sensor is located inside the lock bucket (1), the timer is electrically connected to the lock bucket pressure relief valve (8), the pressure sensor is electrically connected to the amplifier, and the amplifier is electrically connected to the voltage comparator.

6. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 3, characterized in that, The controller includes a PLC controller and a logic AND gate controller. The logic AND gate controller is a 74LS08 AND gate controller. The logic AND gate controller is electrically connected to a timer and a voltage comparator. The lock bucket inlet valve (7), lock bucket pressure relief valve (8), lock bucket flushing water valve (9), lock bucket outlet valve (10), lock bucket circulation pump inlet valve (11), and lock bucket pressurization valve (12) are all electrically connected to the PLC controller.

7. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 6, characterized in that, The lock bucket circulation pump (3) is connected to a drive motor I (13), the lock bucket flushing water tank (4) is connected to a water pump ATM (14), and the gasifier (2) is equipped with a drive motor II (15) at its outlet.

8. The coal gasification furnace lock hopper system for abnormal rapid shutdown according to claim 1, characterized in that, The timer is an NE555 timer, the pressure sensor is an MPM280 pressure sensor, the amplifier is an LM358 amplifier, and the voltage comparator is an LM339 voltage comparator.

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