A combined control method for automatically balancing multi-channel coke oven gas pressure

Abstract

The present invention discloses a combined control method for automatically balancing the pressure of multiple coke oven gases, comprising the following steps: connecting to the pressure measurement points of each gas source and the usage measurement points of each gas user in the original DCS system of the power plant, and remotely controlling the gas release regulating valves of each gas source; measuring the pressure values, target deviation values, and gas usage values ​​of each gas user at each gas source pressure measurement point; comparing the gas pressure target values ​​set by each gas user with the measured gas pressure values, target deviation values, gas usage values, and average gas flow values ​​of each gas user; and outputting different control instructions for the gas release regulating valves of each gas source through a combined calculation method. The combined control method for automatically balancing the pressure of multiple coke oven gases of the present invention has the advantages of automatically adjusting the gas pressure, timely and accurately adjusting the gas pressure of each coking plant, uniformly regulating the pressure, and preventing the backflow of low-pressure incoming gas.

Description

Technical Field

[0001] The invention belongs to the technical field of gas pressure control, and in particular relates to a combined control method for automatically balancing multi-channel coke oven gas pressures. Background Art

[0002] Currently, coal coking plants produce coke oven gas as a byproduct during their production process, which is supplied to downstream thermal power generation companies for fuel. Furthermore, coking ovens consume a certain amount of gas. To ensure a stable fuel supply, downstream thermal power generation companies often simultaneously receive gas from multiple coking plants. Therefore, gas balance is a constant consideration for power generation companies.

[0003] When thermal power generation companies receive gas from multiple coking plants, the plant's shift manager communicates with each coking plant via intercom or phone to adjust gas pressure when power generation load needs to be adjusted. This process often leads to problems such as delayed adjustments and inaccurate adjustments at the coking plants. The various incoming gas streams converge at the main pipe before the booster blowers, resulting in inconsistent pressure regulation and a backflow of low-pressure gas.

[0004] The coking plant's DCS control system already had four gas release regulating valves, each responsible for regulating the gas pressure of its own gas source. Each gas source had a gas pressure deviation. The target gas pressure deviation equaled the target gas pressure minus the measured gas pressure. High pressure meant opening the valve to release gas, while low pressure meant closing the valve to reduce venting and stabilize the gas pressure. However, the plant was located far from the gas consumption point, so changes in gas demand meant untimely regulation and significant lag. This caused significant gas pressure fluctuations and even coke oven shutdowns. Summary of the Invention

[0005] The purpose of the present invention is to provide a combined control method for automatically balancing the pressure of multiple coke oven gases, so as to solve the above-mentioned problems existing in the existing cross-system gas scheduling and control technology, so that power generation enterprises can achieve multi-channel gas pressure balance and thus achieve the goals of "stability, fullness and excellence".

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A combined control method for automatically balancing the pressure of multiple coke oven gases comprises the following steps:

[0008] In the original DCS system of the power plant, the pressure measurement points of each gas source and the usage measurement points of each gas user are connected, and the gas release regulating valves of each gas source are remotely controlled;

[0009] Measure the pressure value, target deviation value and gas usage value of each gas source pressure measuring point and each gas user;

[0010] Compare the gas pressure target value set by each gas user, the gas pressure measurement value of each gas source, the target deviation value, the gas usage value, and the average gas flow value;

[0011] Through the combined calculation method, different control instructions are output for the gas release regulating valves of various gas sources to achieve the purpose of automatically balancing the gas pressures of multiple channels.

[0012] End the operation and enter the next cycle.

[0013] Furthermore, the various coal gas sources include a first coal gas source coking plant, a second coal gas source coking plant, a third coal gas source coking plant and a fourth coal gas source coking plant.

[0014] Furthermore, the method for comparing the gas pressure measurement values ​​of the various gas sources is specifically as follows:

[0015] The gas pressure measurements at each gas source are compared and sorted every 500 milliseconds to determine which gas source has the highest and lowest pressures. This serves as the primary basis for assigning control commands to the gas release regulating valves at each gas source.

[0016] The increase or decrease in the gas usage value of each gas user unit serves as the second basis for allocating control instructions to the gas release regulating valves of each gas source.

[0017] Furthermore, the joint calculation method includes the following steps:

[0018] The first basis of regulation principle:

[0019] Based on the comparison results of the target gas pressure value and the actual gas pressure measurement value, the gas source with the largest gas pressure measurement value and the gas source with the smallest gas pressure measurement value are compared and the target deviation value is sent to the DCS system for judgment. When the target deviation value is small, asynchronous regulation is adopted, and when the deviation is large, synchronous regulation is adopted.

[0020] Asynchronous adjustment for small deviations:

[0021] When 0 < target deviation < 0.2 kPa, only the gas release regulating valve of the gas source with the lowest gas pressure measurement value is closed, and the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid mutual vibration and gas grabbing; closing means increasing gas pressure;

[0022] When -0.2kPa < target deviation value < 0, only the gas release regulating valve of the gas source with the highest gas pressure measurement value is opened, and the openings of the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid simultaneous operation and causing gas pressure fluctuations; opening means reducing gas pressure;

[0023] Synchronous adjustment in case of large deviation:

[0024] When the target deviation value is greater than or equal to 0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are synchronously closed based on the original basic opening to quickly return the gas pressure to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method;

[0025] When the target deviation value is less than or equal to -0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are opened synchronously based on the original basic opening to allow the gas pressure to quickly return to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method.

[0026] Furthermore, the target deviation value is specifically obtained as follows: based on the comparison result of the gas pressure target value and the actual gas pressure measurement value, the obtained target deviation value is transmitted to the DCS system, the original gas pressure target value is automatically corrected and adjusted according to the total deviation value, and the actual gas pressure measurement value is compared with the corrected gas pressure target value to obtain a new target deviation value. When the target deviation value is within the range of ±0.2KPa, it is a small deviation. When the target deviation value is not less than 0.2KPa or not greater than -0.2KPa, it is a large deviation.

[0027] Furthermore, the joint calculation method includes the following steps:

[0028] The second basis for regulation principle:

[0029] Send the gas usage value of each gas user to the DCS system of the gas source;

[0030] Sum up all gas usage values ​​to obtain the total gas usage value and subtract the average gas flow rate five minutes ago to obtain the gas usage deviation value;

[0031] According to the gas usage deviation value, it is converted into the flow characteristic curve of the gas release regulating valve of each gas source, and the gas release regulating valve of each gas source is over-controlled to respond to gas changes in advance, overcome the conduction lag caused by the long pipeline, and achieve gas balance.

[0032] Beneficial effects: The present invention adopts a combined control method for automatically balancing the pressure of multiple coke oven gases. When the power generation load needs to be adjusted, the gas pressure is automatically adjusted, the gas pressure of each coking plant is adjusted in a timely and accurate manner, the pressure is uniformly adjusted, and the backflow of low-pressure gas is prevented, so that power generation enterprises can achieve multi-channel gas pressure balance and thus achieve the goals of "stable, full and excellent". BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of the control method of the present invention. DETAILED DESCRIPTION

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly introduced below in conjunction with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. Example

[0035] like Figure 1 As shown, this embodiment provides a combined control method for automatically balancing the pressure of multiple coke oven gases, comprising the following steps:

[0036] The power plant's existing DCS system connected to pressure measurement points at each gas source and usage measurement points at each gas user. It remotely controlled the gas release regulating valves at each gas source, opening them wide to release gas when pressure was high and closing them narrowly to reduce gas release when pressure was low, thereby stabilizing gas pressure at each source. The gas release regulating valves at the gas source automatically and rapidly controlled the gas release regulating valves at the coking plant's gas source based on gas usage and individual gas pressures. This achieved a dynamic balance between gas production and consumption across the cross-regional gas pipeline network, stabilized gas pressure, satisfied gas users' needs, and enabled the power plant to better respond to State Grid's requirements for power generation load.

[0037] Measure the pressure value, target deviation value and gas usage value of each gas source pressure measuring point and each gas user;

[0038] Compare the gas pressure target value set by each gas user, the gas pressure measurement value of each gas source, the target deviation value, the gas usage value, and the average gas flow value;

[0039] Through the combined calculation method, different control instructions are output for the gas release regulating valves of various gas sources to achieve the purpose of automatically balancing the gas pressures of multiple channels.

[0040] End the operation and enter the next cycle.

[0041] In another embodiment of the present invention, the coal gas sources include a first coal gas source coking plant, a second coal gas source coking plant, a third coal gas source coking plant and a fourth coal gas source coking plant.

[0042] In another embodiment of the present invention, a method for comparing the gas pressure measurement values ​​of various gas sources is specifically as follows:

[0043] The gas pressure measurements at each gas source are compared and sorted every 500 milliseconds to determine which gas source has the highest and lowest pressures. This serves as the primary basis for assigning control commands to the gas release regulating valves at each gas source.

[0044] The increase or decrease in the gas usage value of each gas user unit serves as the second basis for allocating control instructions to the gas release regulating valves of each gas source.

[0045] In another embodiment of the present invention, the method of joint computing includes the following steps:

[0046] The first basis of regulation principle:

[0047] Based on the comparison results of the target gas pressure value and the actual gas pressure measurement value, the gas source with the largest gas pressure measurement value and the gas source with the smallest gas pressure measurement value are compared and the target deviation value is sent to the DCS system for judgment. When the target deviation value is small, asynchronous regulation is adopted, and when the deviation is large, synchronous regulation is adopted.

[0048] Asynchronous adjustment for small deviations:

[0049] When 0 < target deviation < 0.2 kPa, only the gas release regulating valve of the gas source with the lowest gas pressure measurement value is closed, and the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid mutual vibration and gas grabbing; closing means increasing gas pressure;

[0050] When -0.2kPa < target deviation value < 0, only the gas release regulating valve of the gas source with the highest gas pressure measurement value is opened, and the openings of the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid simultaneous operation and causing gas pressure fluctuations; opening means reducing gas pressure;

[0051] Synchronous adjustment in case of large deviation:

[0052] When the target deviation value is greater than or equal to 0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are synchronously closed based on the original basic opening to quickly return the gas pressure to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method;

[0053] When the target deviation value is less than or equal to -0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are opened synchronously based on the original basic opening to allow the gas pressure to quickly return to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method.

[0054] In another embodiment of the present invention, the target deviation value is specifically obtained as follows: based on the comparison result of the gas pressure target value and the actual gas pressure measurement value, the obtained target deviation value is transmitted to the DCS system, and the original gas pressure target value is automatically corrected and adjusted based on the total deviation value. Depending on the size of the target deviation value, the original gas pressure target is increased by 0 to 0.5 kPa to allow the gas release regulating valve to respond in advance and overcome the regulation lag caused by the length of the gas pipeline network. The actual gas pressure measurement value is compared with the corrected gas pressure target value to obtain a new target deviation value. When the target deviation value is within the range of ±0.2 kPa, it is a small deviation. When the target deviation value is not less than 0.2 kPa or not greater than -0.2 kPa, it is a large deviation.

[0055] In another embodiment of the present invention, the method of joint computing includes the following steps:

[0056] The second basis for regulation principle:

[0057] Send the gas usage value of each gas user to the DCS system of the gas source;

[0058] Sum up all gas usage values ​​to obtain the total gas usage value and subtract the average gas flow rate five minutes ago to obtain the gas usage deviation value;

[0059] The gas usage deviation is converted into a flow characteristic curve for each gas source's gas release regulating valve. Override control is then applied to each gas source's gas release regulating valve, enabling proactive response to gas fluctuations and overcoming transmission lag caused by long pipelines to achieve balanced gas usage. This is especially true if a device trips at a gas-consuming unit, significantly reducing gas usage and potentially causing excessive gas pressure on the main pipe, impacting coke oven safety. This override control allows for rapid stabilization of gas network pressure even in the event of an extreme trip.

[0060] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A combined control method for automatically balancing the pressure of multiple coke oven gases, characterized in that: The following steps are involved: In the original DCS system of the power plant, the pressure measurement points of each gas source and the usage measurement points of each gas user are connected, and the gas release regulating valves of each gas source are remotely controlled; Measure the pressure value, target deviation value and gas usage value of each gas source pressure measuring point and each gas user; Compare the gas pressure target value set by each gas user, the gas pressure measurement value of each gas source, the target deviation value, the gas usage value, and the average gas flow value; Through the combined calculation method, different control instructions are output for the gas release regulating valves of various gas sources to achieve the purpose of automatically balancing the gas pressures of multiple channels. End the operation and enter the next cycle; The coal gas sources include a first coal gas source coking plant, a second coal gas source coking plant, a third coal gas source coking plant and a fourth coal gas source coking plant; The method for comparing the gas pressure measurement values ​​of the various gas sources is specifically as follows: The gas pressure measurements at each gas source are compared and sorted every 500 milliseconds to determine which gas source has the highest and lowest pressures. This serves as the primary basis for assigning control commands to the gas release regulating valves at each gas source. The increase or decrease in gas usage of each gas user is used as the second basis for allocating control instructions to the gas release regulating valves of each gas source; The joint calculation method comprises the following steps: The first basis of regulation principle: Based on the comparison results of the target gas pressure value and the actual gas pressure measurement value, the gas source with the largest gas pressure measurement value and the gas source with the smallest gas pressure measurement value are compared and the target deviation value is sent to the DCS system for judgment. When the target deviation value is small, asynchronous regulation is adopted, and when the deviation is large, synchronous regulation is adopted. Asynchronous adjustment for small deviations: When 0 < target deviation < 0.2 kPa, only the gas release regulating valve of the gas source with the lowest gas pressure measurement value is closed, and the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid mutual vibration and gas grabbing; closing means increasing gas pressure; When -0.2kPa < target deviation value < 0, only the gas release regulating valve of the gas source with the highest gas pressure measurement value is opened, and the openings of the gas release regulating valves of the other gas sources remain unchanged, performing pressure balance adjustment in a small range to avoid simultaneous operation and causing gas pressure fluctuations; opening means reducing gas pressure; Synchronous adjustment in case of large deviation: When the target deviation value is greater than or equal to 0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are synchronously closed based on the original basic opening to quickly return the gas pressure to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method; When the target deviation value is less than or equal to -0.2KPa, the amount of gas that needs to be adjusted is large, so the gas release regulating valves of each gas source are opened synchronously based on the original basic opening to allow the gas pressure to quickly return to the range of ±0.2KPa, and then adjusted according to the small deviation asynchronous adjustment method.

2. The combined control method for automatically balancing multi-channel coke oven gas pressure according to claim 1, characterized in that: The specific process for obtaining the target deviation value is as follows: based on the comparison result of the gas pressure target value and the actual gas pressure measurement value, the obtained target deviation value is transmitted to the DCS system, the original gas pressure target value is automatically corrected and adjusted according to the total deviation value, and the actual gas pressure measurement value is compared with the corrected gas pressure target value to obtain a new target deviation value. When the target deviation value is within the range of ±0.2KPa, it is a small deviation. When the target deviation value is not less than 0.2KPa or not greater than -0.2KPa, it is a large deviation.

3. The combined control method for automatically balancing multi-channel coke oven gas pressure according to claim 2, characterized in that: The joint calculation method comprises the following steps: The second basis for regulation principle: Send the gas usage value of each gas user to the DCS system of the gas source; Sum up all gas usage values ​​to obtain the total gas usage value and subtract the average gas flow rate five minutes ago to obtain the gas usage deviation value; According to the gas usage deviation value, it is converted into the flow characteristic curve of the gas release regulating valve of each gas source, and the gas release regulating valve of each gas source is over-controlled to respond to gas changes in advance, overcome the conduction lag caused by the long pipeline, and achieve gas balance.

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