A method for determining the timeout of a coke oven gas exchanger

Abstract

This invention relates to a method for determining the timeout of a coke oven gas exchanger. The method identifies and confirms the timeout phenomenon of the coke oven gas exchanger and displays the result, so that production personnel can intervene and handle it early, prevent uneven furnace temperature heating caused by the timeout, improve coke quality, and reduce the occurrence of environmental accidents.

Description

Technical Field

[0001] This invention relates to the field of automation technology, and more specifically, to a method for determining the timeout of a coke oven gas exchanger. Background Technology

[0002] The coke oven gas exchanger is the core equipment in the coke oven heating system. Its main function is to periodically switch the flow direction of gas, air and exhaust gas to heat the coke oven, ensure the stability and uniformity of the coke oven temperature, and ensure that the coke oven can carry out heating production continuously, efficiently and safely, ultimately improving coke quality and production efficiency.

[0003] A typical gas exchanger includes a chain, an oil pump, an exhaust gas cylinder, and a gas cylinder. When the exchange cycle time is up, the gas exchanger starts the oil pump, driving the gas cylinder and exhaust gas cylinder to move in a forward direction according to a set pattern. The cylinders drive the chain, completing one cycle of exchange on one side of the coke oven before stopping. Then, when the exchange cycle time is up again, the oil pump starts again, driving the gas cylinder and exhaust gas cylinder to move in the opposite direction according to a set pattern (the process is the same, only the direction is reversed). The cylinders drive the chain, completing one cycle of exchange on one side of the coke oven before stopping. This cycle repeats until the next exchange cycle time is up.

[0004] In general, during the switching process of a switch, a PLC is used to control the start of the oil pump and the operation of the gas cylinder and exhaust cylinder. Therefore, sensors to detect the stroke are installed on both the gas cylinder and the exhaust cylinder.

[0005] To achieve the cyclic operation of the switch in the existing PLC control system, the position sensors of each actuation node of the gas cylinder and exhaust gas cylinder must operate reliably and accurately. If the position sensors fail or become inaccurate during the forward or reverse switching process, the switching process will be interrupted, the PLC control cycle will be disrupted, and the switch will be unable to proceed to the next step.

[0006] Currently, most coke oven gas exchanger control systems lack methods and measures for detecting and addressing exchange timeouts, making these issues difficult to detect promptly during coke oven production. Although this fault occurs infrequently (2-3 times per year) and is relatively simple to handle, it is difficult to detect each time it occurs, taking anywhere from half an hour to two hours. This leads to uneven heating in the coke oven, affecting coke quality and greatly increasing the risk of environmental accidents caused by excessive coke oven flue gas emissions. Therefore, it is necessary to improve the existing technology. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a method for judging the timeout of coke oven gas exchangers. This method identifies and confirms the timeout phenomenon of coke oven gas exchangers and displays the result, enabling production personnel to intervene and handle the issue early, thereby preventing uneven furnace temperature heating caused by timeout, improving coke quality, and reducing the occurrence of environmental accidents.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A method for determining the switching timeout of a coke oven gas exchanger, including timeout determination of the switching process; The base time for both the forward and reverse swap processes is set to T0; A bit detected by the sensor at each position of the gas cylinder is taken as 1, and a bit not detected is taken as 0; Reversal process timeout judgment: During the forward reversal process, the change state of the gas cylinder start position sensor and the gas cylinder end position sensor changes from 1, 0 to 0, 1. The actual time required for the change from 1, 0 to 0, 1 is taken as T3. When T3 > T0, it indicates that the forward reversal process has timed out. During the reverse exchange process, the state changes from 0, 1 to 1, 0 of the gas cylinder start position sensor and the gas cylinder end position sensor. The actual time required to change from 0, 1 to 1, 0 is taken as T4. When T4 > T0, it indicates that the reverse exchange process has timed out.

[0009] In one embodiment, the method for determining the timeout of the coke oven gas exchanger further includes determining the timeout of the exchange cycle: the unilateral heating time for both forward and reverse exchange is set to T1, and the reference cycle time for both forward and reverse exchange is T2 = T0 + T1. The actual cycle of forward exchange starts timing from the starting position of the gas cylinder as 1 and ends timing when the ending position of the gas cylinder is 1. This time period is called T5. When T5 > T2, it means that the forward exchange cycle has timed out. The actual cycle of reverse exchange starts timing from the end position of the gas cylinder at 1 and ends timing from the start position of the gas cylinder at 1. This time period is called T6. When T6 > T2, it means that the reverse exchange cycle has timed out.

[0010] In one embodiment, during forward exchange, when T3≤T0 and T5>T2, it indicates that the unilateral heating time in the forward exchange cycle has exceeded the limit.

[0011] In one embodiment, during reverse exchange, when T4≤T0 and T6>T2, it indicates that the unilateral heating time in the reverse exchange cycle has timed out.

[0012] In summary, the present invention has the following beneficial effects: This invention proposes a feasible method for judging the phenomenon of coke oven gas exchanger timeout. By judging and confirming the phenomenon of coke oven gas exchanger timeout, the invention outputs and displays the result, so that production personnel can intervene and deal with it early, prevent uneven furnace temperature heating caused by timeout, improve coke quality, and reduce the occurrence of environmental accidents. Attached Figure Description

[0013] Figure 1 This is a schematic diagram showing the positions of the gas cylinder and waste gas cylinder before the forward exchange process of the coke oven gas exchanger begins.

[0014] Figure 2 This is a schematic diagram showing the indicator slider of the gas cylinder reaching the middle position during the forward exchange process of the coke oven gas exchanger.

[0015] Figure 3 This is a schematic diagram showing the indicator slider of the exhaust gas cylinder reaching the end position during the forward exchange process of the coke oven gas exchanger.

[0016] Figure 4 This is a schematic diagram showing the indicator slider of the gas cylinder reaching the end position during the forward exchange process of the coke oven gas exchanger.

[0017] Figure 5 This is a schematic diagram showing the indicator slider of the gas cylinder reaching the middle position during the reverse exchange process of the coke oven gas exchanger.

[0018] Figure 6 This is a schematic diagram showing the indicator slider of the exhaust gas cylinder reaching the starting position during the forward exchange process of the coke oven gas exchanger.

[0019] Figure 7 This is a schematic diagram showing the indicator slider of the gas cylinder reaching the starting position during the forward exchange process of the coke oven gas exchanger.

[0020] Figure 8 This is the operating principle of the coke oven gas exchanger. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] It is worth noting that the directional terms such as "up" and "down" used in this article are all relative to the perspective of the attached figures and are only for the purpose of description. They should not be interpreted as limitations on the technical solutions.

[0023] like Figure 1-7 As shown, the switching process of the existing coke oven gas exchanger is as follows.

[0024] The forward exchange process is as follows: Figure 1As shown, before the coke oven gas exchanger starts forward exchange, the gas cylinder indicator slider points to the starting position of the gas cylinder, and the waste gas cylinder indicator slider points to the starting position of the waste gas cylinder. When the exchange cycle time is up, the PLC controls the coke oven gas exchanger to start the oil pump, driving the gas cylinder and waste gas cylinder to move in a forward direction according to a set pattern: the gas cylinder moves first, and the gas cylinder indicator slider moves according to the pattern. Figure 2 In the positive direction of the exchange, after moving from the starting position to the middle position of the gas cylinder, the gas cylinder stops moving; After the gas cylinder stops operating, the waste gas cylinder begins to operate. Figure 3 The exhaust cylinder is in the direction of positive exchange. Its exhaust cylinder indicator slider moves from the starting position to the end position of the exhaust cylinder and then the exhaust cylinder stops moving. After the exhaust gas cylinder stops operating, the gas cylinder restarts, and the gas cylinder indicator slider moves from the middle position. Figure 3 The positive exchange direction is shown. Figure 4 The gas cylinder completes a full forward exchange process after reaching its endpoint. After the forward exchange is complete, the positions of the gas cylinder and exhaust gas cylinder are as follows: Figure 4 As shown.

[0025] The reverse swap process is as follows: Figure 4 The diagram shows the positions of the gas cylinder and waste gas cylinder before the reverse exchange process of the coke oven gas exchanger begins. The gas cylinder indicator slider points to the end position of the gas cylinder, and the waste gas cylinder indicator slider points to the end position of the waste gas cylinder. When the exchange cycle time is up, the PLC controls the gas exchanger to start the oil pump, driving the gas cylinder and the waste gas cylinder to move in reverse according to a certain pattern: the gas cylinder moves first, and the gas cylinder indicator slider moves according to the pattern. Figure 5 The direction of the reverse exchange is such that after moving from the end position to the middle position of the gas cylinder, the gas cylinder stops moving. After the gas cylinder stops operating, the waste gas cylinder begins to operate. Figure 6 The direction of the reverse exchange of the exhaust cylinder is shown. After the exhaust cylinder indicator slider moves from the end position to the start position of the exhaust cylinder, the exhaust cylinder stops moving. After the exhaust gas cylinder stops operating, the gas cylinder restarts, and the gas cylinder indicator slider moves from the middle position. Figure 6 The reverse exchange direction is shown. Figure 7 The gas cylinder, as shown, completes a full reverse exchange process after starting from the initial position.

[0026] After the reverse exchange is completed, the positions of the gas cylinder and the exhaust gas cylinder during their strokes are as follows: Figure 7 As shown. After the reverse swap is completed, the forward swap is performed when the swap cycle time expires, and this process is repeated.

[0027] Coke oven gas exchanger control PLC press Figure 8The logic rules are used to control the actions of the switch.

[0028] Based on the above-mentioned operation process of the coke oven gas exchanger, the present invention proposes a method for judging the switching timeout of the coke oven gas exchanger, including the judgment of the switching process timeout. The base time for both the forward and reverse swap processes is set to T0; A bit detected by the sensor at each position of the gas cylinder is taken as 1, and a bit not detected is taken as 0; Reversal process timeout judgment: During the forward reversal process, the change state of the gas cylinder start position sensor and the gas cylinder end position sensor changes from 1, 0 to 0, 1. The actual time required for the change from 1, 0 to 0, 1 is taken as T3. When T3 > T0, it indicates that the forward reversal process has timed out. During the reverse exchange process, the state changes from 0, 1 to 1, 0 of the gas cylinder start position sensor and the gas cylinder end position sensor. The actual time required to change from 0, 1 to 1, 0 is taken as T4. When T4 > T0, it indicates that the reverse exchange process has timed out.

[0029] The forward exchange process begins at the starting position of the gas cylinder and ends at the ending position, while the reverse exchange process begins at the ending position of the gas cylinder and ends at the starting position. Therefore, the starting and ending positions of both forward and reverse exchanges are the starting and ending positions of the gas cylinder, respectively. Logical judgments can then be made based on the signal states of the sensors used at these two positions.

[0030] For the reversing process, since the starting and ending positions of the gas cylinder are fixed, the distance between them remains constant. When the same oil pump drives the same oil cylinder during reversal, theoretically, the time taken for the forward and reverse reversing processes is the same, assuming no cylinder malfunctions. For example, the reversing process time T0 of a coke oven gas exchanger is 25 seconds. Any malfunction during the forward or reverse reversing process (such as sensor failure or mechanical mechanism malfunction) will cause the reversing process time to exceed 25 seconds, thus allowing for quick identification of a malfunction in the reversing process.

[0031] Before the exchange begins, the 1, 0 or 0, 1 states of the gas cylinder start position sensor and the gas cylinder end position sensor are normal. However, in actual production, the exchange may function normally during the switching process, but malfunction during the single-sided heating time T1. This causes the 1, 0 or 0, 1 states of the gas cylinder start position sensor and the gas cylinder end position sensor to become abnormal before the exchange begins. This results in an increase in the single-sided heating time T1. Since the exchange cycle time of the coke oven gas exchanger = T0 + T1, an increase in T1 will also lead to an increase in the exchange cycle time of the gas exchanger, resulting in an exchange timeout. The above-mentioned method for judging the timeout of the switching process will then be ineffective.

[0032] Furthermore, the method for judging the timeout of the coke oven gas exchanger also includes the judgment of the timeout of the exchange cycle: set the single-sided heating time of the forward exchange and the reverse exchange to T1, then the reference cycle time of the forward exchange and the reverse exchange is T2=T0+T1. The actual cycle of forward exchange starts timing from the starting position of the gas cylinder as 1 and ends timing when the ending position of the gas cylinder is 1. This time period is called T5. When T5 > T2, it means that the forward exchange cycle has timed out. The actual cycle of reverse exchange starts timing from the end position of the gas cylinder at 1 and ends timing from the start position of the gas cylinder at 1. This time period is called T6. When T6 > T2, it means that the reverse exchange cycle has timed out.

[0033] Observe the entire exchange cycle, such as Figure 8 As shown, during the forward exchange T0 and T1, the gas cylinder moves from the "gas cylinder starting position" to the "gas cylinder ending position," eventually ending when the "gas cylinder ending position" is set to 1. Therefore, it can be determined that the cycle time of the forward exchange starts when the "gas cylinder starting position" is set to 1 and ends when the "gas cylinder ending position" is set to 1. Similarly, during the reverse exchange T0 and T1, the gas cylinder moves from the "gas cylinder ending position" to the "gas cylinder starting position," eventually ending when the "gas cylinder starting position" is set to 1. Therefore, it can be determined that the cycle time of the reverse exchange starts when the "gas cylinder ending position" is set to 1 and ends when the "gas cylinder starting position" is set to 1.

[0034] Combination Figure 8 It can be seen that when the "gas cylinder start position" is set to 1, the timing begins. Since setting the "gas cylinder start position" to 1 indicates that the sensor has detected the slider, and the slider will remain at this position for a period of time, which is actually T1, the timing ends the instant the "gas cylinder end position" is set to 1. Therefore, the entire time period includes T0 and T1. Similarly, during the reverse exchange, the timing starts from when the "gas cylinder end position" is set to 1 and ends when the "gas cylinder start position" is set to 1, which also includes T0 and T1.

[0035] As mentioned above, the cycle time for both forward and reverse switching includes T0 and T1. Therefore, this method can be used to resolve the problem of switching timeouts caused by switch failures during the "single-sided heating time" T1, making it impossible to determine the cause.

[0036] Furthermore, in the forward exchange, when T3≤T0 and T5>T2, it indicates that the unilateral heating time in the forward exchange cycle has exceeded the time limit.

[0037] Furthermore, in the reverse exchange, when T4≤T0 and T6>T2, it indicates that the unilateral heating time in the reverse exchange cycle has exceeded the time limit.

[0038] This invention covers the entire heating and exchange cycle of the coke oven gas exchanger, enabling rapid and accurate diagnosis of exchange timeout faults caused by malfunctions during operation. By programming and integrating with various brands of programmable logic controllers (PLCs), the invention can output the judgment results through the PLC, such as through a host computer screen warning, audible and visual alarm warning, or coke oven industrial control interlock output signals, thus expanding its applications. It fills the long-standing gap in existing coke oven gas exchanger control systems, which are mostly unable to identify and diagnose exchange timeouts. This solves the long-standing problem of uneven coke oven heating, substandard coke quality, and environmental incidents caused by excessive coke oven flue gas emissions due to exchange timeouts.

[0039] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for determining the timeout of a coke oven gas exchanger, characterized in that, This includes timeout detection during the reversing process; The reference time for both the forward and reverse swap processes is set to T0; A bit detected by the sensor at each position of the gas cylinder is taken as 1, and a bit not detected is taken as 0; Reversal process timeout judgment: During the forward reversal process, the change state of the gas cylinder start position sensor and the gas cylinder end position sensor changes from 1, 0 to 0, 1. The actual time required for the change from 1, 0 to 0, 1 is taken as T3. When T3 > T0, it indicates that the forward reversal process has timed out. During the reverse exchange process, the state changes from 0, 1 to 1, 0 of the gas cylinder start position sensor and the gas cylinder end position sensor. The actual time required to change from 0, 1 to 1, 0 is taken as T4. When T4 > T0, it indicates that the reverse exchange process has timed out.

2. The method for determining the timeout of a coke oven gas exchanger as described in claim 1, characterized in that, It also includes the judgment of the exchange cycle timeout: set the unilateral heating time of both forward and reverse exchange to T1, then the reference cycle time of both forward and reverse exchange is T2=T0+T1; The actual cycle of forward exchange starts timing from the starting position of the gas cylinder as 1 and ends timing when the ending position of the gas cylinder is 1. This time period is called T5. When T5 > T2, it means that the forward exchange cycle has timed out. The actual cycle of reverse exchange starts timing from the end position of the gas cylinder at 1 and ends timing from the start position of the gas cylinder at 1. This time period is called T6. When T6 > T2, it means that the reverse exchange cycle has timed out.

3. The method for determining the timeout of a coke oven gas exchanger as described in claim 2, characterized in that, In forward exchange, when T3≤T0 and T5>T2, it indicates that the unilateral heating time in the forward exchange cycle has exceeded the time limit.

4. The method for determining the timeout of a coke oven gas exchanger as described in claim 2, characterized in that, In reverse exchange, when T4≤T0 and T6>T2, it indicates that the unilateral heating time in the reverse exchange cycle has exceeded the time limit.

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