Device for preventing peroxy explosion of coal water slurry gasification furnace

Abstract

The utility model discloses a device for preventing peroxide explosion of a coal water slurry gasification furnace, which comprises a coal slurry concentration meter, two ends of the coal slurry concentration meter are connected with a main pipeline between a coal slurry tank and a coal slurry pump through branch pipes, and a signal output end of the coal slurry concentration meter is connected with a signal input end of a distributed control system. According to the device disclosed by the utility model, the occurrence of peroxidation explosion in the gasification furnace caused by dilution of the coal slurry concentration is avoided, and the operation stability and safety of the system are improved; after receiving a low coal slurry concentration alarm, an operator checks whether flushing water enters the coal slurry tank and confirms that the flushing water is normal, and then increases the coal consumption in the slurrying system to increase the concentration of the coal slurry, so that the problem that the concentration of the coal slurry is reduced is quickly solved, the occurrence of abnormal conditions is effectively prevented, and the system production is recovered.

Description

Technical Field

[0001] This utility model belongs to the field of chemical technology, specifically relating to a device for preventing over-oxygen explosion in a coal-water slurry gasifier. Background Technology

[0002] Texaco's coal gasification process primarily utilizes GE's pressurized coal-water slurry gasification technology. Water, additives, and other auxiliary materials are added to the coal to be gasified, and the mixture is ground in a rod mill to produce a coal slurry with a concentration of approximately 60%. This slurry is then pressurized by a high-pressure pump and reacted with 99.6% pure oxygen from the air separation system in a gasifier to generate syngas, primarily composed of carbon monoxide and hydrogen. In the GE process package, when the oxygen-to-coal ratio reaches a high value of 710 for 0.5 seconds, the gasification system will automatically trip. This safety interlock is based on the premise that a high oxygen-to-coal ratio can lead to an over-oxygen explosion in the gasifier. Currently, the coal slurry process lacks online concentration monitoring, relying solely on analytical sampling. This method is lagging and cannot promptly reflect changes in coal slurry concentration. If the coal slurry concentration decreases, the flow meter fluctuation is minimal, and the oxygen-to-coal ratio will not fluctuate, thus not triggering the interlock trip. However, the actual reaction within the gasifier already involves over-oxygenation, which can cause the gasifier temperature to rise, damaging internal components and potentially leading to an explosion. In actual production, due to issues with coal type and personnel operation, the coal slurry concentration often decreases. In particular, when flushing the coal slurry circulation pipeline, flushing water enters the coal slurry tank, causing a decrease in coal slurry concentration. If the plunger valve is not closed tightly, flushing water may seep into the coal slurry tank from the bottom when the standby high-pressure coal slurry pump is being tested for water pressure. This can lead to a rapid decrease in the coal slurry concentration at the inlet of the high-pressure coal slurry pump in the operating system, resulting in over-oxygenation in the gasifier. Utility Model Content

[0003] Technical problem solved: In response to the above-mentioned technical problems, this utility model provides a device to prevent over-oxygen explosion in a coal-water slurry gasifier, which improves the stability and safety of system operation, effectively curbs the occurrence of abnormal situations, and restores system production.

[0004] Technical solution: A device for preventing over-oxygen explosion in a coal-water slurry gasifier, comprising a coal slurry concentration meter, the two ends of which are connected to the main pipeline between the coal slurry tank and the coal slurry pump via branch pipes, and the signal output terminal of the coal slurry concentration meter is connected to the signal input terminal of a distributed control system.

[0005] Preferably, valves are provided on the branch pipes at both ends of the coal slurry concentration meter.

[0006] Furthermore, the valve is a ball valve.

[0007] Preferably, the device further includes an alarm, the signal input terminal of which is connected to the signal output terminal of the distributed control system.

[0008] Preferably, the signal from the coal slurry concentration meter is transmitted to the distributed control system via a transmitter.

[0009] Preferably, the coal slurry concentration meter is interlocked with the valve position of the oxygen regulating valve in the distributed control system, and a corresponding "interlock activation / deactivation" button is provided.

[0010] Beneficial effects: This utility model device avoids the occurrence of oxygen explosion in the gasifier due to the dilution of coal slurry concentration, and improves the stability and safety of system operation; after receiving the low coal slurry concentration alarm, the operator checks whether flushing water has entered the coal slurry tank. After confirming that it is normal, the operator increases the amount of coal used in the slurry preparation system to increase the coal slurry concentration, thereby quickly solving the problem of low coal slurry concentration and effectively preventing the occurrence of abnormal situations and restoring system production. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of a device for preventing over-oxygen explosion in a coal-water slurry gasifier according to this utility model.

[0012] The numbers in the diagram are: 1. Coal slurry tank, 2. Branch pipe, 3. Coal slurry concentration meter, 4. Valve, 5. Coal slurry pump, 6. Gasifier, 7. Oxygen regulating valve. Detailed Implementation

[0013] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings. Example 1

[0014] Reference Figure 1 A device for preventing over-oxygen explosion in a coal-water slurry gasifier includes a coal slurry concentration meter 3. The two ends of the coal slurry concentration meter 3 are connected to the main pipeline between the coal slurry tank 1 and the coal slurry pump 5 via branch pipes 2. The signal output terminal of the coal slurry concentration meter 3 is connected to the signal input terminal of a distributed control system (DCS).

[0015] The branch pipes 2 at both ends of the coal slurry concentration meter 3 are equipped with valves 4, which are ball valves, to facilitate isolation and maintenance.

[0016] The signal from the coal slurry concentration meter 3 is transmitted to the distributed control system via a transmitter.

[0017] The coal slurry concentration meter 3 is interlocked with the oxygen regulating valve 7 in the distributed control system, and a corresponding "interlock activation / deactivation" button is set.

[0018] Based on the above-mentioned device, the device for preventing over-oxygen explosion in the coal-water slurry gasifier also includes an alarm, the signal input terminal of which is connected to the signal output terminal of the distributed control system.

[0019] During the daily operation of the high-pressure coal slurry pump 5, the coal slurry concentration meter 3 transmits the detected signal to the DCS screen via a transmitter, enabling real-time monitoring of the coal slurry concentration. A low-concentration alarm value is set. When the coal slurry concentration is below 59%, the alarm notifies the DCS operator and interlocks with the oxygen regulating valve 7, establishing an independent interlock between the coal slurry concentration meter (CT) and the oxygen regulating valve 7. When the coal slurry concentration is below 55%, the interlock is triggered, closing the oxygen regulating valve at 5%. When the coal slurry concentration continues to decrease to 49%, the oxygen regulating valve at 5% is closed again. When the coal slurry concentration is below 42%, the SIS safety interlock system trips, ensuring the gasifier does not experience an over-oxygen explosion due to excessively low coal slurry concentration. When the system is shut down or the coal slurry concentration meter is under maintenance, there is no coal slurry in the pipeline, and the concentration cannot be measured. The interlock is deactivated using the "Interlock Activation / Deactivation" button.

[0020] The use of this utility model device avoids the occurrence of an oxygen explosion in the gasifier 6 due to the dilution of coal slurry concentration, and improves the stability and safety of system operation. After receiving the low coal slurry concentration alarm, the operator checks whether flushing water has entered the coal slurry tank. After confirming that it is normal, the operator increases the amount of coal used in the slurry preparation system to increase the coal slurry concentration, thereby quickly solving the problem of low coal slurry concentration and effectively preventing the occurrence of abnormal situations and restoring system production.

[0021] The embodiments described herein are preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape, and principle of this utility model should be included within the scope of protection of this utility model.

Claims

1. A device for preventing excessive oxygen explosion in a coal-water slurry gasifier, characterized in that: The system includes a coal slurry concentration meter (3), the two ends of which are connected to the main pipeline between the coal slurry tank (1) and the coal slurry pump (5) through branch pipes (2), and the signal output end of the coal slurry concentration meter (3) is connected to the signal input end of the distributed control system.

2. The device for preventing over-oxygen explosion in a coal-water slurry gasifier according to claim 1, characterized in that: Valves (4) are provided on the branch pipes (2) at both ends of the coal slurry concentration meter (3).

3. The device for preventing over-oxygen explosion in a coal-water slurry gasifier according to claim 2, characterized in that: The valve (4) is a ball valve.

4. The device for preventing over-oxygen explosion in a coal-water slurry gasifier according to claim 1, characterized in that: It also includes an alarm, the signal input of which is connected to the signal output of the distributed control system.

5. The device for preventing over-oxygen explosion in a coal-water slurry gasifier according to claim 1, characterized in that: The signal from the coal slurry concentration meter (3) is transmitted to the distributed control system via a transmitter.

6. The device for preventing over-oxygen explosion in a coal-water slurry gasifier according to claim 1, characterized in that: The coal slurry concentration meter (3) is interlocked with the valve position of the oxygen regulating valve (7) in the distributed control system, and a corresponding "interlock activation / deactivation" button is set.

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