System for controlling automatic heating of coke oven gas

Abstract

The invention relates to a system for controlling automatic heating of coke oven gas and relates to the technical field of coke oven gas systems. The device comprises a coke oven gas pipeline, a first thermometer and a second thermometer are arranged at the two ends of the coke oven gas pipeline respectively, a heat tracing pipe is arranged on the outer wall of the coke oven gas pipeline in a surrounding mode, one end of the heat tracing pipe is connected with a steam source valve set and a control valve set, and the other end of the heat tracing pipe is connected with a drain valve set. And a spoiler is arranged in the coke oven gas pipeline. The device has the advantages that the phenomenon that the heat exchanger tube bundle is blocked is effectively avoided, the heating temperature of the coking coal medium is controlled in real time, hydrocarbon is prevented from being decomposed due to the too high heating temperature, cleaning-free maintenance is achieved, and the working condition of a boiler burner is more stable.

Description

Technical Field

[0001] The present application relates to the technical field of coke oven gas systems, and in particular to a system for controlling automatic heating of coke oven gas. Background Art

[0002] In recent years, the recycling and utilization of coke oven gas resources has gradually become popular in the thermal power generation industry. Affected by the chemical properties of coking coal, which are mainly hydrogen, methane, benzene, phenol, naphthalene, moisture and tar, the following problems exist: 1. Residual moisture and naphthalene components in coke oven gas are prone to form ice crystals and naphthalene crystals at the burner valve plate in winter, resulting in a reduction in the gas flow area and unstable flame combustion in the furnace; 2. Methane and other hydrocarbons will decompose when the heat storage chamber is too high, which will reduce the calorific value of the coke oven gas, and the free carbon produced by decomposition will easily cause the heat storage chamber to clog; 3. Impurities such as tar are easy to accumulate and adhere to the traditional heat exchanger tube bundle, causing the tube bundle to be clogged, requiring frequent and regular cleaning, and extremely inconvenient to use and maintain; therefore, there is an urgent need for a system with a simple structure that can reasonably control the automatic heating temperature of coke oven gas to solve the above problems. Summary of the Invention

[0003] In order to effectively avoid the blockage of the heat exchanger tube bundle, control the temperature of the coking coal medium in real time, avoid the decomposition of hydrocarbons due to excessive heating temperature, and achieve cleaning-free maintenance, so that the boiler burner operating condition is more stable, the present application provides a system for controlling the automatic heating of coke oven gas.

[0004] The present application provides a system for controlling the automatic heating of coke oven gas using the following technical solutions: A system for controlling the automatic heating of coke oven gas comprises a coke oven gas pipeline, wherein a first thermometer and a second thermometer are respectively provided at both ends of the coke oven gas pipeline, a heating pipe is provided around the outer wall of the coke oven gas pipeline, one end of the heating pipe is connected to a steam source valve group and a control valve group, and the other end of the heating pipe is connected to a steam trap group, and a spoiler is provided in the coke oven gas pipeline.

[0005] Preferably, the steam source valve group includes a first valve and a second valve, the first valve and the second valve are connected in parallel to the heating pipe, the first valve is used for the four-extraction steam supply of the unit, and the second valve is used for the auxiliary steam network steam supply; the rated parameters of the first valve are 394℃ / 1.18Mpa, and the rated parameters of the second valve are 184℃ / 1Mpa.

[0006] Preferably, the control valve group is arranged between the steam source valve group and the heating pipe, and the control valve group includes a first manual valve, an electric regulating valve, a second manual valve and a first bypass manual valve. The first manual valve, the electric regulating valve and the second manual valve are connected to the steam source valve group in sequence. The first bypass manual valve is connected in parallel to the part composed of the first manual valve, the electric regulating valve and the second manual valve. The electric regulating valve is communicated with the second temperature meter, and the electric regulating valve controls the opening of its valve core based on the set value of the second temperature meter.

[0007] Preferably, the steam trap group includes a third manual valve, a steam trap, a fourth manual valve and a second bypass manual valve. The third manual valve, the float-type automatic steam trap and the fourth manual valve are connected to the heating pipe in sequence, and the second bypass manual valve is connected in parallel with the part consisting of the third manual valve, the float-type automatic steam trap and the fourth manual valve.

[0008] Preferably, the material of the heating pipe includes φ57*4 / 20# seamless steel pipe, and the installation pitch of the heating pipe is 20-30 cm.

[0009] Preferably, the spoiler adopts a swirl blade spoiler structure, and the spoiler is installed at the inlet section of the coke oven gas pipeline heating zone.

[0010] Preferably, the outer wall of the coke oven gas pipeline is provided with aluminum silicate fiber cotton with a thickness of 5 cm and aluminum skin with a thickness of 2 mm.

[0011] Preferably, a safety accessory is provided at one end of the coke oven gas pipeline close to the user end.

[0012] In summary, this application includes at least one of the following beneficial technical effects: 1. This application adopts a swirl blade turbulence structure to enhance the heat exchange effect, which is less likely to cause the heat exchange tube bundle to be blocked and avoids frequent cleaning and maintenance; 2. The system of this application has a simple structure, low manufacturing cost and is easy to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of a system for controlling automatic heating of coke oven gas according to an embodiment of the present application.

[0014] Figure 2 It is a flow chart of the PID automatic control logic of the embodiment of the present application.

[0015] Figure 3 Schematic diagram of the structure of the spoiler of the embodiment of the present application.

[0016] Explanation of the accompanying symbols: 1. Steam source valve group; 101. First valve; 102. Second valve; 2. Control valve group; 201. First manual valve; 202. Electric regulating valve; 203. Second manual valve; 204. First bypass manual valve; 3. Heating pipe; 4. Steam trap valve group; 401. Third manual valve; 402. Float-type automatic steam trap; 403. Fourth manual valve; 404. Second bypass manual valve; 5. Turbulator; 6. Coke oven gas pipeline; T1. First thermometer; T2. Second thermometer. DETAILED DESCRIPTION

[0017] The following is combined with Figure 1-3 This application is described in further detail.

[0018] The embodiment of the present application discloses a system for controlling the automatic heating of coke oven gas. Figure 1 , including a coke oven gas pipeline 6, with a first thermometer T1 and a second thermometer T2 respectively provided at both ends of the coke oven gas pipeline 6, a heat tracing pipe 3 is provided around the outer wall of the coke oven gas pipeline 6, and the heat tracing pipe 3 is in a countercurrent arrangement with the coking coal medium. In this embodiment, the material of the heat tracing pipe 3 includes but is not limited to φ57*4 / 20# seamless steel pipe, and the installation pitch of the heat tracing pipe 3 is 20-30cm to meet the heat exchange effect. The structural form of the heat tracing pipe 3 of the present application is different from the heat exchange tube bundle inside the traditional heat exchanger, which can effectively avoid the problem of blockage and difficulty in cleaning of the traditional heat exchange tube bundle, so that the heat tracing pipe 3 of the present application is free from frequent cleaning and maintenance.

[0019] Reference Figure 1 One end of the heat tracing pipe 3 is connected to the control valve group 2 and the steam source valve group 1 in sequence. The steam source valve group 1 includes a first valve 101 and a second valve 102. The first valve 101 and the second valve 102 are connected in parallel. The first valve 101 is used for the four-extraction steam supply of the unit, and the second valve 102 is used for the auxiliary steam network steam supply; the rated parameters of the first valve 101 are 394℃ / 1.18Mpa, and the rated parameters of the second valve 102 are 184℃ / 1Mpa; during the cold start of the unit or when the four-extraction pipeline is involved, When there is no four-extraction self-steam supply, the auxiliary steam network can be used to supply steam by closing the first valve 101 and opening the second valve 102; when the unit is started or the auxiliary steam pipeline is involved in maintenance operations, there is no auxiliary steam network, the second valve 102 can be closed and the first valve 101 can be opened to use the unit's four-extraction self-steam, and the unit can be started from the cold start state by switching the steam source valve group 1. The heating pipe 3 can have the ability of uninterrupted steam supply, realizing one steam source in use and one steam source in standby.

[0020] Reference Figure 1 and Figure 2The control valve group 2 includes a first manual valve 201, an electric regulating valve 202, a second manual valve 203 and a first bypass manual valve 204. The first manual valve 201, the electric regulating valve 202 and the second manual valve 203 are connected to the steam source valve group 1 in sequence. The first bypass manual valve 204 is connected in parallel to the part composed of the first manual valve 201, the electric regulating valve 202 and the second manual valve 203. The control valve group 2 is used to meet the needs of main bypass switching and daily isolation of the electric regulating valve 202; in this embodiment, the electric regulating valve 202 is communicated with the second thermometer T2, and the electric regulating valve 202 controls the opening of its valve core based on the set value of the second thermometer T2. The set value range of the second thermometer T2 is any value between 10-40°C. The PID logic is used to adjust the opening of its valve core to achieve efficient and automatic control of the temperature of the coke oven gas medium after heating.

[0021] Reference Figure 1 and Figure 2 , the PID automatic control logic adopted by this application system is: 1. Set the T2 temperature to a fixed value (any value in the reasonable range of 10-40℃), and through PID regulation, the opening of the electric regulating valve 202 automatically adjusts the steam inlet volume according to the temperature; 2. When the difference between the PID output temperature and the set temperature is greater than 5°C, the automatic adjustment is canceled, the DCS panel will give an alarm, and manual intervention is required to adjust the temperature; 3. Set the DCS panel to have a light indication alarm for T1 and T2 < 0°C (i.e. the temperature display value on the panel changes to a prominent color to remind monitoring personnel to pay attention to the low temperature of the upstream coke oven gas); 4. The DCS panel is set with an audible and visual alarm when T2>50℃ to remind monitoring personnel to intervene in time when abnormal situations occur.

[0022] Reference Figure 1 The other end of the heating pipe 3 is connected to a drain valve group 4, which includes a third manual valve 401, a drain valve, a fourth manual valve 403 and a second bypass manual valve 404. The third manual valve 401, the float-type automatic drain valve 402 and the fourth manual valve 403 are connected to the heating pipe 3 in sequence, and the second bypass manual valve 404 is connected in parallel with the part composed of the third manual valve 401, the float-type automatic drain valve 402 and the fourth manual valve 403; the drain valve group 4 is used to meet the needs of main bypass switching and daily isolation of the float-type automatic drain valve 402. After low-temperature heating, the condensate of about 70-80℃ is transported to the boiler discharge expansion tank and the sewage cooling pool by the float-type automatic drain valve 402, and is mixed with the unit's discharge and drainage condensate for recycling.

[0023] Reference Figure 1 and Figure 3A spoiler 5 is provided in the coke oven gas pipeline 6. The spoiler 5 adopts a swirl blade spoiler structure. The spoiler 5 is installed at the inlet section of the heating section of the coke oven gas pipeline 6 to achieve a turbulent flow effect of the coke medium and enhance the heat exchange effect of the rear end heating pipe 3 on the medium in the coke oven gas pipeline 6. In daily use, only tar and other attachments usually appear on the surface of this structure, and no blockage occurs.

[0024] Reference Figure 1 The outer wall of the coke oven gas pipeline 6 is provided with 5 cm thick aluminum silicate fiber cotton and 2 mm thick aluminum sheet to improve the heat preservation and anti-scalding performance; the coke oven gas pipeline 6 is provided with a safety auxiliary component at one end close to the user end to improve the safety of the system. In this embodiment, the safety auxiliary component adopts an explosion-proof membrane.

[0025] The implementation principle of a system for controlling the automatic heating of coke oven gas in an embodiment of the present application is as follows: the operating personnel monitors the gas medium temperature gauges T1 and T2, and when the ambient temperature is low, completes the normal pipe heating operation of the system before putting it into operation; in the early stage of commissioning, the opening of the electric regulating valve 202 is manually adjusted to control the coke oven gas medium temperature gauge T2 to be between 10 and 40°C; in the middle and late stages of commissioning, after the T2 temperature stabilizes, the T2 temperature is set to a fixed value (such as 25°C) through the temperature setting window on the DCS panel, and the PID automatic control logic is put into use to achieve efficient and automatic control of the temperature of the coke oven gas medium after heating; through this application, the phenomenon of heat exchanger tube bundle blockage is effectively avoided, the temperature of the heated coke coal medium is controlled in real time, and hydrocarbons are prevented from being decomposed due to excessive heating temperature, while achieving cleaning-free maintenance, making the boiler burner operating condition more stable.

[0026] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A system for controlling automatic heating of coke oven gas, comprising a coke oven gas pipeline, characterized in that: A first thermometer and a second thermometer are respectively provided at both ends of the coke oven gas pipeline. A heating pipe is provided around the outer wall of the coke oven gas pipeline. One end of the heating pipe is connected to a steam source valve group and a control valve group, and the other end of the heating pipe is connected to a drain valve group. A spoiler is provided in the coke oven gas pipeline.

2. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The steam source valve group includes a first valve and a second valve, the first valve and the second valve are connected in parallel to the heating pipe, the first valve is used for the four-extraction steam supply of the unit, and the second valve is used for the auxiliary steam network steam supply; the rated parameters of the first valve are 394℃ / 1.18Mpa, and the rated parameters of the second valve are 184℃ / 1Mpa.

3. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The control valve group is arranged between the steam source valve group and the heating pipe. The control valve group includes a first manual valve, an electric regulating valve, a second manual valve and a first bypass manual valve. The first manual valve, the electric regulating valve and the second manual valve are connected to the steam source valve group in sequence. The first bypass manual valve is connected in parallel to the part composed of the first manual valve, the electric regulating valve and the second manual valve. The electric regulating valve is communicated with the second temperature meter. The electric regulating valve controls the opening of its valve core based on the set value of the second temperature meter.

4. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The steam trap group includes a third manual valve, a steam trap, a fourth manual valve and a second bypass manual valve. The third manual valve, the float-type automatic steam trap and the fourth manual valve are connected to the heating pipe in sequence. The second bypass manual valve is connected in parallel with the part consisting of the third manual valve, the float-type automatic steam trap and the fourth manual valve.

5. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The material of the heating pipe includes φ57*4 / 20# seamless steel pipe, and the installation pitch of the heating pipe is 20-30cm.

6. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The spoiler adopts a swirl blade spoiler structure and is installed at the inlet section of the coke oven gas pipeline heating section.

7. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The outer wall of the coke oven gas pipeline is provided with aluminum silicate fiber cotton with a thickness of 5 cm and aluminum skin with a thickness of 2 mm.

8. The system for controlling automatic heating of coke oven gas according to claim 1, characterized in that: The coke oven gas pipeline is provided with a safety accessory at one end close to the user end.

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