Control method and device of coal lock gas recovery system and coal lock gas recovery system

Abstract

This application provides a control method, apparatus, and system for a coal lock gas recovery system, relating to the field of control technology. The method includes: acquiring operating parameters of coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; connecting the pressure relief outlet of each coal lock to a coal lock gas holder; determining the maximum total pressure relief of each coal lock during operation based on the operating parameters; placing the reflux valve of the coal lock gas compressor in the coal lock gas recovery system in a closed state; wherein the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is located on the reflux circuit of the coal lock gas compressor; controlling the coal lock gas compressor to output gas at its rated gas delivery rate, ensuring that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and controlling the pressure relief sequence of each coal lock so that none of the coal locks are simultaneously in a pressure relief state. This reduces the risk of coal lock gas being forced to flare due to gas holder level interlocking.

Description

Technical Field

[0001] This application relates to the field of control technology, and in particular to a control method, apparatus and coal lock gas recovery system for a coal lock gas recovery system. Background Technology

[0002] Coal lock gas recovery is an important part of pressurized gasification process. It collects and outputs the crude coal gas discharged during the coal lock depressurization stage of the gasifier to achieve resource recovery and utilization. It is widely used in energy-saving, emission-reduction and efficiency-enhancing scenarios in the coal chemical industry.

[0003] However, in actual production operations, the coal locks of multiple gasifiers independently perform periodic pressurization and depressurization operations. When multiple coal locks depressurize simultaneously, the instantaneous amount of crude gas generated far exceeds the upper limit of the matching between the gas holder's buffer capacity and the compressor's output capacity. This causes the gas holder liquid level to rise rapidly and trigger the high-liquid-level interlock protection, forcing a large amount of crude gas to be switched to the combustion chamber for combustion and venting. This results in frequent venting of coal lock gas into the combustion chamber, leading to a significant waste of crude gas resources, a substantial increase in raw material costs and energy consumption, pollutant emissions during combustion and venting, and a continuous increase in the operating load of the combustion chamber system due to frequent venting, resulting in increased equipment maintenance costs and safety hazards. Summary of the Invention

[0004] Based on this, this application provides a control method, apparatus, and system for a coal lock gas recovery system, which can reduce the risk of coal lock gas being forced to vent due to liquid level interlocking in the gas holder. The specific solution is as follows:

[0005] A control method for a coal lock gas recovery system includes:

[0006] The operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system are obtained; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder;

[0007] Based on the operating parameters, determine the maximum total pressure relief of each of the coal locks during operation;

[0008] The reflux valve of the coal lock gas compressor in the coal lock gas recovery system is placed in the closed state; wherein, the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is set on the reflux circuit of the coal lock gas compressor;

[0009] The coal lock gas compressor is controlled to output gas at the rated gas supply, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and the pressure relief sequence of each coal lock is controlled so that each coal lock is not in a pressure relief state at the same time.

[0010] Optionally, in the above method, determining the maximum total pressure relief of each coal lock during operation based on the operating parameters includes:

[0011] Based on the single depressurization duration, depressurization gas volume per unit time, and depressurization cycle period in the operating parameters, calculate the total depressurization gas volume corresponding to the coal lock in the depressurization state within any time window.

[0012] The total pressure relief volume is determined as the maximum total pressure relief volume.

[0013] Optionally, in the above method, controlling the depressurization sequence of each coal lock so that none of the coal locks are in a depressurization state simultaneously includes:

[0014] Obtain historical pressure relief data for each of the aforementioned coal locks;

[0015] Based on the historical depressurization data, a depressurization time window is allocated to each coal lock, so that the depressurization time windows of any two coal locks are not simultaneous.

[0016] According to the allocated pressure relief time window, each coal lock is controlled to perform pressure relief operation in sequence, so that each coal lock is not in a pressure relief state at the same time.

[0017] Optionally, after controlling the coal-lock gas compressor to output gas at the rated gas delivery rate, the above method further includes:

[0018] Obtain the current liquid level and rate of change of the coal lock gas holder;

[0019] Based on the current liquid level and the rate of change of the liquid level, determine the expected peak value of the liquid level in the coal lock gas holder during the next depressurization cycle;

[0020] If the expected peak value exceeds the upper limit of the preset safety range, the gas delivery rate of the coal-lock compressor shall be increased before the start of the next depressurization cycle.

[0021] The above methods may also include:

[0022] Under the condition that the total output of the coal lock gas compressor is greater than the maximum total pressure relief and that each coal lock does not depressurize at the same time, when the liquid level of the coal lock gas holder is detected to be lower than the lower limit of the preset safety range, the reflux valve of the coal lock gas compressor is controlled to be in the open state until the liquid level of the gas holder is restored to the safe range, and then the reflux valve of the coal lock gas compressor is placed in the closed state.

[0023] In response to the gas holder liquid level being maintained within the safe range, the gas holder inlet valve of the coal lock gas holder is kept open, allowing all coal lock gas to enter the coal lock gas holder for output by the coal lock gas compressor.

[0024] A control device for a coal lock gas recovery system includes:

[0025] The system comprises an acquisition unit, a determination unit, an execution unit, and a control unit, wherein the acquisition unit is a signal acquisition module connected to a coal lock operation sensor; the determination unit and the control unit are logic operation modules integrated within a controller; and the execution unit is a relay output module electrically connected to the compressor return valve.

[0026] The acquisition unit is used to acquire the operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder.

[0027] The determining unit is used to determine the maximum total pressure relief of each of the coal locks during operation based on the operating parameters;

[0028] The execution unit is used to close the reflux valve of the coal lock gas compressor in the coal lock gas recovery system; wherein the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is located on the reflux circuit of the coal lock gas compressor.

[0029] The control unit is used to control the coal lock gas compressor to output gas at the rated gas supply, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and to control the pressure relief sequence of each coal lock so that each coal lock is not in a pressure relief state at the same time.

[0030] Optionally, the control unit in the aforementioned device includes:

[0031] The calculation subunit is used to calculate the total amount of gas released from the coal lock in the depressurization state within any time window, based on the single depressurization duration, the amount of gas released per unit time, and the depressurization cycle period in the operating parameters.

[0032] A subunit is defined to determine the total pressure relief volume as the maximum total pressure relief volume.

[0033] A coal lock gas recovery system, comprising:

[0034] Multiple gasifiers, each of which has a corresponding coal lock, gas holder inlet valve, coal lock gas holder, fire cabinet, coal lock gas compressor and controller;

[0035] Each of the coal locks is used to release coal lock gas during the depressurization phase;

[0036] The inlet of the coal lock gas holder is connected to the pressure relief outlet of each coal lock through the gas holder inlet valve, and is used to store the coal lock gas discharged by the coal lock;

[0037] The fire cabinet is connected to the pressure relief outlet of each coal lock through the interlocked venting pipeline of the gas holder inlet valve;

[0038] The coal lock gas compressor is connected to the outlet of the coal lock gas holder and is used to output the coal lock gas in the coal lock gas holder;

[0039] The controller is connected to the pressure relief control valve of each coal lock, the control module of the coal lock gas compressor, and the liquid level sensor signal of the coal lock gas tank, respectively, and is used to collect operating parameters and send control commands. The controller is specifically configured to execute the control method of the coal lock gas recovery system as described above.

[0040] Optionally, in the above system, the number of coal lock gas compressors is at least two, and the total rated gas delivery capacity of each coal lock gas compressor is greater than the maximum total pressure relief capacity of multiple coal locks during operation.

[0041] Optionally, in the above system, the gas holder inlet valve is used to interlock and close when the gas holder liquid level reaches a preset high threshold, so as to switch the coal lock gas to the fire holder.

[0042] This application provides a control method, apparatus, and system for a coal lock gas recovery system. The method includes: acquiring operating parameters of coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; wherein the pressure relief outlet of each coal lock is connected to a coal lock gas holder; determining the maximum total pressure relief of each coal lock during operation based on the operating parameters; placing the reflux valve of the coal lock gas compressor in the coal lock gas recovery system in a closed state; wherein the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is located on the reflux circuit of the coal lock gas compressor; controlling the coal lock gas compressor to output gas at a rated gas delivery rate, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and controlling the pressure relief sequence of each coal lock based on a preset pressure relief timing control strategy, so that each coal lock is not in a pressure relief state at the same time. Applying the method provided in this application can reduce the risk of coal lock gas being forced to flare due to gas holder level interlocking, and achieves full recovery of coal lock gas. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0044] Figure 1 A flowchart of a control method for a coal lock gas recovery system provided in this application;

[0045] Figure 2A flowchart illustrating the process for determining the maximum total pressure relief of each coal lock during operation, as provided in this application;

[0046] Figure 3 A schematic diagram of the control device for a coal lock gas recovery system provided in this application;

[0047] Figure 4 This application provides a schematic diagram of the structure of a coal lock gas recovery system; Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] This application provides a control method for a coallock gas recovery system. This method can be applied to a controller or control equipment connected to the coallock gas recovery system for communication purposes. The flowchart of the method is shown below. Figure 1 As shown, it specifically includes:

[0051] S101: Obtain the operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder.

[0052] In this embodiment, the coal lock is a feeding device for the pressurized gasification unit. During the depressurization stage of the coal feeding cycle, it discharges crude coal gas, i.e., coal lock gas. Each gasifier is equipped with a corresponding coal lock, and the depressurization outlet of each coal lock is connected to the coal lock gas holder. The coal lock gas discharged during the depressurization stage enters the coal lock gas holder for temporary storage through this connection path.

[0053] The operating parameters refer to data characterizing the coal lock's depressurization condition. Examples include the duration of a single depressurization cycle, the amount of gas depressurized per unit time, and the depressurization cycle period. These operating parameters can be obtained based on the coal lock's historical operating records or on real-time acquired operating data.

[0054] S102: Based on operating parameters, determine the maximum total pressure relief of each coal lock during operation.

[0055] In this embodiment, the maximum total pressure relief can refer to the maximum value of the total pressure relief gas volume corresponding to all coal locks that may be in a pressure relief state simultaneously within any time window during the operation of multiple coal locks.

[0056] For example, based on the collected data on the duration of a single depressurization, the amount of depressurized gas per unit time, and the depressurization cycle, the number of coal locks that may be simultaneously in a depressurization state within a time window of a depressurization cycle can be calculated. Then, based on this number of coal locks and the amount of depressurized gas per coal lock, the maximum total depressurization amount can be determined. The maximum total depressurization amount characterizes the maximum intake load that the gas holder may face instantaneously.

[0057] S103: Set the reflux valve of the coal lock gas compressor in the coal lock gas recovery system to the closed state; wherein, the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is set on the reflux circuit of the coal lock gas compressor.

[0058] In this embodiment, the coal lock gas compressor is connected to the outlet of the coal lock gas holder, used to pressurize and output the temporarily stored coal lock gas in the holder to downstream devices. A reflux valve is installed on the reflux circuit of the coal lock gas compressor. In partial load operation mode, the reflux valve is open, and part of the gas output by the compressor returns to the compressor inlet via the reflux circuit, causing the actual output of the compressor to be lower than the rated gas delivery. Closing the reflux valve blocks the reflux circuit, switching the compressor's operating mode from partial load mode to full output mode.

[0059] S104: Control the coal lock gas compressor to output gas at the rated gas supply, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and control the pressure relief sequence of each coal lock so that each coal lock is not in the pressure relief state at the same time.

[0060] In this embodiment, the rated gas delivery volume refers to the design output capacity of the compressor. The compressor is controlled to output gas at the rated gas delivery volume so that the total output volume is greater than the maximum total pressure relief volume.

[0061] Optionally, the depressurization timing of each coal lock can be controlled based on a preset depressurization timing control strategy. This strategy uses the constraint that the depressurization time windows of any two or more coal locks do not overlap, configuring sequentially staggered depressurization time windows for each coal lock. Controlling the depressurization timing of each coal lock based on this strategy ensures that each coal lock performs depressurization actions sequentially without being in a depressurization state simultaneously, thus preventing the concentrated influx of multiple coal lock gases into the gas holder from the operational perspective.

[0062] In implementation, the determination of the maximum total pressure relief and the formulation of the pressure relief timing control strategy can be carried out in tandem. Specifically, based on the pressure relief cycle and duration of each coal lock, the timing distribution characteristics of the pressure relief actions of each coal lock can be analyzed. Staggered pressure relief time windows can be allocated to each coal lock, ensuring that each pressure relief time window is unique. Based on these timing distribution characteristics, the maximum number of coal locks that can simultaneously depressurize within any time window and their corresponding total pressure relief gas volume can be calculated, thereby determining the maximum total pressure relief. During operation, each coal lock is controlled to perform pressure relief operations sequentially according to the allocated pressure relief time windows.

[0063] For example, when a conflict occurs in the allocation of pressure relief time windows during system operation, the current pressure relief time windows allocated to each coal lock can be obtained, and it can be determined whether there are any identical pressure relief time windows. If there are identical ones, the pressure relief start time of at least one coal lock can be adjusted so that each pressure relief time window is different.

[0064] In some embodiments, when the total output of the coal lock gas compressor is greater than the maximum total pressure relief and each coal lock does not depressurize at the same time, the liquid level of the coal lock gas holder is maintained within a preset safe range, the gas holder inlet valve remains open, and all the coal lock gas discharged during the pressure relief stage enters the gas holder and is recovered by the compressor output, thereby achieving full recovery of the coal lock gas.

[0065] In one embodiment provided in this application, based on the above-described scheme, optionally, the process of determining the maximum total pressure relief of each coal lock during operation based on operating parameters is as follows: Figure 2 As shown, it includes:

[0066] S201: Based on the single depressurization duration, depressurization gas volume per unit time, and depressurization cycle period in the operating parameters, calculate the total depressurization gas volume corresponding to the coal lock in the depressurization state within any time window.

[0067] The time window refers to a continuous period of time extracted based on the depressurization cycle. Based on the depressurization cycle and duration of each coal lock, the number of coal locks that may be simultaneously in a depressurization state within this time window can be determined. Then, based on the number of coal locks and the depressurization gas volume per unit time, the corresponding total depressurization gas volume can be calculated.

[0068] In some embodiments, the percentage of time a single coal lock is in a depressurized state within a complete cycle can be determined first based on the depressurization cycle period and single depressurization duration of each coal lock. Then, combining the total number of coal locks in the system and the relative phase relationship of the cycle periods of each coal lock, the maximum number of coal locks simultaneously in a depressurized state within a time window of arbitrary length can be determined. Then, based on the maximum number of coal locks simultaneously depressurized and the depressurization gas volume per unit time of a single coal lock, the total depressurization gas volume within that time window can be calculated.

[0069] For example, when the production system is running at full load, it includes multiple gasifiers. Each gasifier's coal lock independently performs pressure charging and depressurization operations according to its own cycle. Under the constraint of the ratio of depressurization duration to cycle, the maximum number of gasifiers that can be depressurized simultaneously is determined by traversing the time sequence combination of each coal lock's cycle. The product of this maximum number of gasifiers and the depressurization gas volume of a single gasifier is the total depressurization gas volume.

[0070] S202: Determine the total pressure relief volume as the maximum total pressure relief volume.

[0071] In this embodiment, the maximum total pressure relief represents the maximum intake load that the gas holder may face instantaneously. The maximum total pressure relief is determined based on the number of coal locks, the pressure relief rate, and the pressure relief cycle period. After determining the maximum total pressure relief, the adjustment of the compressor's total output is based on the aforementioned maximum total pressure relief, ensuring that the total output is greater than this reference value.

[0072] In one embodiment provided in this application, based on the above-described scheme, optionally, the depressurization timing of each coal lock is controlled so that none of the coal locks are in a depressurization state simultaneously, including:

[0073] Obtain historical pressure relief data for each coal lock;

[0074] Based on historical depressurization data, a depressurization time window is allocated to each coal lock, so that the depressurization time windows of any two coal locks are not simultaneous;

[0075] According to the allocated depressurization time window, each coal lock is controlled to perform depressurization operation in sequence, so that each coal lock is not in a depressurization state at the same time.

[0076] In this embodiment, historical pressure relief data refers to the time record of each pressure relief action of the coal lock within its historical operating cycle. For example, it includes the start time, end time, and time interval between each pressure relief action. Historical pressure relief data can be obtained by extracting it from the coal lock's operating log or by reading it from the historical operating condition records of the control system.

[0077] Specifically, by statistically analyzing historical pressure relief data, the relative positions and intervals of the pressure relief actions of each coal lock on the time axis are determined. Based on this, a pressure relief start time and duration are assigned to each coal lock, forming a unique pressure relief time window for each coal lock. During the allocation process, the pressure relief time windows are constrained to not overlap in time sequence, ensuring that the pressure relief time windows of all coal locks are arranged sequentially on the time axis without overlap.

[0078] Optionally, based on the pressure relief time window corresponding to each coal lock, the corresponding coal lock is triggered to perform pressure relief action at the beginning of the window and stops pressure relief at the end of the window. Each coal lock completes pressure relief in sequence according to the order of the time windows, thereby ensuring at the operational level that at most only one coal lock is in the pressure relief state at any given time.

[0079] In one embodiment provided in this application, based on the above-described solution, optionally, after controlling the coal-lock gas compressor to output gas at the rated gas delivery rate, the method further includes:

[0080] Obtain the current liquid level and rate of change of the coal lock gas holder;

[0081] Based on the current liquid level and the rate of change of liquid level, determine the expected peak value of the liquid level in the coal lock gas holder during the next depressurization cycle;

[0082] If the expected peak exceeds the upper limit of the preset safety range, increase the gas delivery rate of the coal-lock compressor before the start of the next depressurization cycle.

[0083] In this embodiment, the current liquid level refers to the real-time storage height of the coal lock gas in the gas holder, which can be obtained by a liquid level detection device installed in the gas holder. The liquid level change rate characterizes the rise and fall of the liquid level in the gas holder per unit time, which can be obtained by differential calculation based on multiple continuously collected liquid level values, or it can be directly output by the liquid level detection device.

[0084] In this embodiment, the next depressurization cycle refers to the time period required for each coal lock to complete one depressurization operation in sequence. The expected peak value is determined by superimposing the current liquid level with the cumulative change in the liquid level change rate during the duration of the next depressurization cycle to obtain the estimated value of the gas holder liquid level at the end of the next depressurization cycle. When the liquid level change rate is positive, the expected peak value is higher than the current liquid level; when the liquid level change rate is negative, the expected peak value is lower than the current liquid level.

[0085] The safe range refers to the permissible fluctuation range of the gas holder liquid level. The upper limit of the safe range is lower than the interlocking closure threshold of the gas holder inlet valve. When the expected peak exceeds the upper limit of the safe range, it indicates that if the current output is maintained, there is a risk that the gas holder liquid level will exceed the safe range in the next depressurization cycle. Increasing the compressor's gas supply before the start of the next depressurization cycle can preemptively lower the gas holder liquid level before the coal lock gas rushes into the gas holder, creating a buffer space for the gas intake in the next depressurization cycle and ensuring that the gas holder liquid level remains within the safe range in the next depressurization cycle.

[0086] In one embodiment provided in this application, based on the above-described solution, optionally, it further includes:

[0087] Under the condition that the total output of the coal lock gas compressor is greater than the maximum total pressure relief and that each coal lock does not depressurize at the same time, when the liquid level of the coal lock gas holder is detected to be lower than the lower limit of the preset safety range, the reflux valve of the coal lock gas compressor is controlled to be in the open state until the liquid level of the gas holder is restored to the safe range, and then the reflux valve of the coal lock gas compressor is put in the closed state.

[0088] In response to the gas holder liquid level being maintained within a safe range, the gas holder inlet valve is kept open, allowing all coal lock gas to enter the gas holder for output by the coal lock gas compressor.

[0089] In this embodiment, the total output exceeding the maximum total pressure relief means that the compressor's gas output capacity exceeds the maximum instantaneous gas intake the gas holder can withstand within any time window, resulting in a stable state where the outflow of gas from the gas holder exceeds the inflow. Specifically, through the constraints of the pressure relief timing control strategy, the pressure relief actions of each coal lock are arranged sequentially on the time axis, ensuring that the pressure relief time windows of two or more coal locks do not overlap. Under these conditions, the coal lock gas received by the gas holder enters at a steady rate and is continuously output by the compressor, causing the gas holder liquid level to fluctuate within a preset safe range without triggering a high-level interlock.

[0090] Optionally, the safe range refers to the permissible liquid level range for gas holder operation. Its upper limit is below the interlocking closure threshold of the gas holder inlet valve, and its lower limit is above the minimum liquid level requirement for normal gas holder operation. If the gas holder liquid level is maintained within the safe range, the gas holder inlet valve can remain open, allowing all coallock gas to enter the gas holder and be output by the coallock gas compressor. The opening and closing of the gas holder inlet valve is controlled by the gas holder liquid level interlock. When the liquid level is within the safe range, the inlet valve remains open, and all coallock gas discharged from each coal lock enters the gas holder through the inlet valve, preventing the interlocking closure and switching to the fire holder due to excessive liquid level. All coallock gas entering the gas holder is pressurized by the coallock gas compressor and output to downstream units, achieving full recovery of the coallock gas.

[0091] In some embodiments, this application addresses the industry problem of overlapping depressurization sequences of multiple coal locks in a pressurized gasification process, which leads to a rapid rise in the liquid level of the gas holder and triggers interlocking venting. It achieves full recovery of coal lock gas through dual improvements of equipment-side parameter optimization and operation-side timing control.

[0092] Optionally, based on the charging and depressurization cycle of multiple gasifier coal locks during full-load operation of the production system, operating parameters such as the single depressurization duration, depressurization gas volume per unit time, and depressurization cycle period of each coal lock can be obtained. This determines the maximum total depressurization volume corresponding to the simultaneous depressurization of multiple coal locks within any time window. The return valve of the coal lock gas compressor is then placed in the closed state, allowing the compressor to output gas at the rated gas delivery volume, thus creating a gas output condition where the total output volume is greater than the maximum total depressurization volume. Simultaneously, based on the historical depressurization data of each coal lock, the temporal distribution characteristics of the depressurization actions are analyzed, and depressurization time windows that are staggered in time sequence are allocated to each coal lock. Each coal lock is controlled to perform depressurization operations sequentially according to the allocated windows, ensuring that no two or more coal locks are in a depressurization state at the same time.

[0093] Specifically, multiple gasifiers are equipped with multiple coal locks. Each coal lock's pressure relief outlet is connected to a coal lock gas holder. The coal lock gas compressor is connected to the gas holder outlet, and a return valve is installed on its return loop. The gas holder is equipped with an inlet valve, which interlocks and closes when the gas holder level reaches a preset high threshold, switching the coal lock gas to the firebox. Under the coordinated control of the staggered timing of the equipment output and the operation, the gas holder level is maintained within a safe range, the inlet valve remains open, and all coal lock gas discharged during the pressure relief phase enters the gas holder and is pressurized and output to downstream units by the compressor. This achieves full recovery of the coal lock gas and reduces the risk of coal lock gas being forced into the firebox for venting due to gas holder level interlocking.

[0094] This application also provides a control device for a coallock gas recovery system, the structural schematic diagram of which is shown below. Figure 3 As shown, it includes:

[0095] The system comprises an acquisition unit 301, a determination unit 302, an execution unit 303, and a control unit 304. The acquisition unit 301 is a signal acquisition module connected to a coal lock operation sensor; the determination unit 302 and the control unit 304 are logic operation modules integrated within a controller; and the execution unit 303 is a relay output module electrically connected to the compressor return valve.

[0096] The acquisition unit 301 is used to acquire the operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder.

[0097] The determining unit 302 is used to determine the maximum total pressure relief of each coal lock during operation based on the operating parameters;

[0098] The execution unit 303 is used to put the reflux valve of the coal lock gas compressor in the coal lock gas recovery system into the closed state; wherein, the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is set on the reflux circuit of the coal lock gas compressor;

[0099] The control unit 304 is used to control the coal lock gas compressor to output gas at the rated gas delivery volume, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief volume, and to control the pressure relief sequence of each coal lock so that each coal lock is not in the pressure relief state at the same time.

[0100] In one embodiment provided in this application, based on the above-described solution, optionally, the control unit includes:

[0101] The calculation subunit is used to calculate the total amount of gas released from the coal lock in the depressurization state within any time window, based on the single depressurization duration, the amount of gas released per unit time, and the depressurization cycle period in the operating parameters.

[0102] Define the sub-unit to determine the total pressure relief volume as the maximum total pressure relief volume.

[0103] The specific principles and execution processes of each unit and module in the control device of the coal lock gas recovery system disclosed in the above-described embodiments of this application are the same as the control method of the coal lock gas recovery system disclosed in the above-described embodiments of this application. Please refer to the corresponding parts of the control method of the coal lock gas recovery system provided in the above-described embodiments of this application, and they will not be repeated here.

[0104] This application embodiment also provides a storage medium, which includes stored instructions, wherein, when the instructions are executed, the device where the storage medium is located controls the control method of the above-described coal lock gas recovery system.

[0105] This application also provides a coallock gas recovery system, the structural schematic diagram of which is shown below. Figure 4 As shown, it specifically includes:

[0106] Multiple gasifiers 401, coal lock 402 for each gasifier 401, gas holder inlet valve 403, coal lock gas holder 404, fire cabinet 405, coal lock gas compressor 406 and controller 407;

[0107] Each coal lock 402 is used to release coal lock gas during the depressurization phase;

[0108] The inlet of the coal lock gas holder 404 is connected to the pressure relief outlet of each coal lock 402 through the gas holder inlet valve, and is used to store the coal lock gas discharged from the coal lock 402;

[0109] Fire cabinet 404 is connected to the pressure relief outlet of each coal lock through the interlock venting pipeline of the gas holder inlet valve;

[0110] The coal lock gas compressor 406 is connected to the outlet of the coal lock gas holder 404 and is used to output the coal lock gas in the coal lock gas holder 404.

[0111] The controller 407 is configured to execute the control method of the coal lock gas recovery system described above.

[0112] In one embodiment provided in this application, based on the above-described scheme, optionally, the number of coal lock gas compressors is at least two, and the total rated gas delivery capacity of each coal lock gas compressor is greater than the maximum total pressure relief capacity of multiple coal locks during operation.

[0113] In one embodiment provided in this application, based on the above-described scheme, optionally, the gas holder inlet valve is used to interlock and close when the gas holder liquid level reaches a preset high limit threshold, so as to switch the coal lock gas to the fire holder.

[0114] In some embodiments, the controller uses a Siemens S7-400 PLC, the timing control logic is implemented through ladder diagram programming, and the pressure relief time window can be configured via an HMI touch screen.

[0115] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For apparatus embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0116] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0117] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0118] The present application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present application. Therefore, the content of this specification should not be construed as a limitation of the present application.

Claims

1. A control method for a coal lock gas recovery system, characterized in that, include: The operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system are obtained; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder; Based on the operating parameters, determine the maximum total pressure relief of each of the coal locks during operation; The reflux valve of the coal lock gas compressor in the coal lock gas recovery system is placed in the closed state; wherein, the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is set on the reflux circuit of the coal lock gas compressor; The coal lock gas compressor is controlled to output gas at the rated gas supply, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and the pressure relief sequence of each coal lock is controlled so that each coal lock is not in a pressure relief state at the same time.

2. The control method according to claim 1, characterized in that, The determination of the maximum total pressure relief of each coal lock during operation based on the operating parameters includes: Based on the single depressurization duration, depressurization gas volume per unit time, and depressurization cycle period in the operating parameters, calculate the total depressurization gas volume corresponding to the coal lock in the depressurization state within any time window. The total pressure relief volume is determined as the maximum total pressure relief volume.

3. The control method according to claim 1, characterized in that, The control of the depressurization timing of each coal lock, so that none of the coal locks are in a depressurization state at the same time, includes: Obtain historical pressure relief data for each of the aforementioned coal locks; Based on the historical depressurization data, a depressurization time window is allocated to each coal lock, so that the depressurization time windows of any two coal locks are not simultaneous. According to the allocated pressure relief time window, each coal lock is controlled to perform pressure relief operation in sequence, so that each coal lock is not in a pressure relief state at the same time.

4. The control method according to claim 1, characterized in that, After controlling the coal-lock compressor to output gas at the rated gas delivery rate, the method further includes: Obtain the current liquid level and rate of change of the coal lock gas holder; Based on the current liquid level and the rate of change of the liquid level, determine the expected peak value of the liquid level in the coal lock gas holder during the next depressurization cycle; If the expected peak value exceeds the upper limit of the preset safety range, the gas delivery rate of the coal-lock compressor shall be increased before the start of the next depressurization cycle.

5. The control method according to any one of claims 1 to 4, characterized in that, Also includes: Under the condition that the total output of the coal lock gas compressor is greater than the maximum total pressure relief and that each coal lock does not depressurize at the same time, when the liquid level of the coal lock gas holder is detected to be lower than the lower limit of the preset safety range, the reflux valve of the coal lock gas compressor is controlled to be in the open state until the liquid level of the gas holder is restored to the safe range, and then the reflux valve of the coal lock gas compressor is placed in the closed state. In response to the gas holder liquid level being maintained within the safe range, the gas holder inlet valve of the coal lock gas holder is kept open, allowing all coal lock gas to enter the coal lock gas holder for output by the coal lock gas compressor.

6. A control device for a coal lock gas recovery system, characterized in that, include: The system comprises an acquisition unit, a determination unit, an execution unit, and a control unit, wherein the acquisition unit is a signal acquisition module connected to a coal lock operation sensor; the determination unit and the control unit are logic operation modules integrated within a controller; and the execution unit is a relay output module electrically connected to the compressor return valve. The acquisition unit is used to acquire the operating parameters of the coal locks corresponding to multiple gasifiers in the coal lock gas recovery system; wherein, the pressure relief outlet of each coal lock is connected to the coal lock gas holder. The determining unit is used to determine the maximum total pressure relief of each of the coal locks during operation based on the operating parameters; The execution unit is used to close the reflux valve of the coal lock gas compressor in the coal lock gas recovery system; wherein the coal lock gas compressor is connected to the outlet of the coal lock gas holder, and the reflux valve is located on the reflux circuit of the coal lock gas compressor. The control unit is used to control the coal lock gas compressor to output gas at the rated gas supply, so that the total output of the coal lock gas compressor is greater than the maximum total pressure relief, and to control the pressure relief sequence of each coal lock so that each coal lock is not in a pressure relief state at the same time.

7. The apparatus according to claim 6, characterized in that, The control unit includes: The calculation subunit is used to calculate the total amount of gas released from the coal lock in the depressurization state within any time window, based on the single depressurization duration, the amount of gas released per unit time, and the depressurization cycle period in the operating parameters. A subunit is defined to determine the total pressure relief volume as the maximum total pressure relief volume.

8. A coal lock gas recovery system, characterized in that, include: Multiple gasifiers (401), a coal lock (402), a gas holder inlet valve (403), a coal lock gas holder (404), a fire cabinet (405), a coal lock gas compressor (406), and a controller (407) for each gasifier (401); Each of the coal locks (402) is used to release coal lock gas during the depressurization phase; The inlet of the coal lock gas holder (404) is connected to the pressure relief outlet of each coal lock (402) through the gas holder inlet valve (403) for storing the coal lock gas discharged by the coal lock (402); The fire cabinet (405) is connected to the pressure relief outlet of each of the coal locks (402) through the interlocked venting pipeline of the gas cabinet inlet valve (403); The coal lock gas compressor (406) is connected to the outlet of the coal lock gas holder (404) and is used to output the coal lock gas in the coal lock gas holder (404); The controller (407) is connected to the pressure relief control valve of each coal lock (402), the control module of the coal lock gas compressor (406), and the liquid level sensor signal of the coal lock gas holder (404) respectively, for collecting operating parameters and sending control commands. The controller is specifically configured to execute the control method of the coal lock gas recovery system as described in any one of claims 1 to 5.

9. The coal lock gas recovery system according to claim 8, characterized in that, The number of the coal lock gas compressors (406) is at least two, and the total rated gas delivery of each of the coal lock gas compressors (406) is greater than the maximum total pressure relief of the multiple coal locks during operation.

10. The coal lock gas recovery system according to claim 8, characterized in that, The gas holder inlet valve (403) is used to interlock and close when the gas holder liquid level reaches a preset high limit threshold, so as to switch the coal lock gas to the fire holder (405).

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