A low-concentration coal-bed gas explosion-suppression type concentration control method based on a PLC

Abstract

The application discloses a low-concentration coal bed gas explosion-suppression type concentration-raising control method based on a PLC, which is applied to a control system of low-concentration coal bed gas explosion-suppression type concentration-raising, and the control system comprises a PLC controller, a compressor, a total valve, a plurality of valves, a pressure swing adsorption system, a plurality of relays, an alarm module, a pressure transmitter, a temperature transmitter and a concentration transmitter. The method is to analyze the values of the temperature transmitter, the pressure transmitter and the concentration transmitter of a buffer tank and an adsorption tower in the equipment by using the PLC controller, so as to control the power of the plurality of valves and the compressor and the alarm module. The application can monitor the concentration of the coal bed gas in real time, and can optimize and control the detection data and the adjusting parameters in the concentration-raising process in real time, and can timely alarm when an explosion occurs, so as to ensure that the whole technological process is in a safe and efficient operation state.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of industrial production control, in particular to a low-concentration coal-bed gas explosion-suppression type concentration-raising control method based on PLC. BACKGROUND

[0002] Coal-bed gas is a gas with methane (CH4) as the main component. Low-concentration (≤20-30%) coal-bed gas is exhausted during extraction, which not only causes waste of resources, but also aggravates the greenhouse effect. From the current development trend of coal-bed gas utilization in China, the potential for development and utilization of low-concentration coal-bed gas is huge. At present, more research results in the field of low-concentration coal-bed gas concentration-raising are pressure swing adsorption technology, vacuum adsorption technology and membrane separation technology. The shortcomings of the adsorption method are: in the process of use, the dust, smoke and other impurities in the waste gas need to be pretreated; high-temperature waste gas needs to be cooled. The investment cost is large. The shortcomings of membrane separation technology are: the membrane surface is easy to be polluted, which reduces the membrane separation performance, so a membrane surface cleaning method suitable for the process needs to be used; the stability, drug resistance, heat resistance and solvent resistance are limited, so the range of use is limited; the function of the single membrane separation technology is limited, and it needs to be used with other separation technologies.

[0003] Pressure swing adsorption has some deficiencies in practical application. First, in the "desorption" stage, when one adsorption tank is desorbed, a part of the gas produced by another adsorption tank is generally used for auxiliary desorption, which is easy to cause backflow, affecting the preparation of product gas; second, for the produced gas, a buffer tank needs to be set due to pressure problems, and the produced gas needs to be temperature-controlled. The existing equipment needs more devices and it is difficult to achieve the effect of buffering and temperature control. SUMMARY

[0004] The present application is to solve the above-mentioned deficiencies of the prior art, and proposes a low-concentration coal-bed gas explosion-suppression type concentration-raising control method based on PLC. The concentration of coal-bed gas can be monitored in real time, and the detection data and adjustment parameters in the concentration-raising process are optimized and controlled in real time. When an explosion occurs, an alarm is given in time, so as to ensure that the entire process is in a safe and efficient operation state.

[0005] To achieve the above-mentioned application purposes, the following technical solutions are adopted:

[0006] The low-concentration coal-bed gas explosion-suppression type concentration-raising control method based on PLC is characterized in that it is applied to a control system for low-concentration coal-bed gas explosion-suppression type concentration-raising. The control system comprises a PLC controller, a compressor, a total valve, a plurality of valves, a pressure swing adsorption system, a plurality of relays, an alarm module, a pressure transmitter, a temperature transmitter and a concentration transmitter.

[0007] The pressure swing adsorption system comprises a raw material tank, a buffer tank, six adsorption towers, a waste gas tank, and a product tank.

[0008] A total valve is arranged between the raw material tank and the compressor and connected by a gas guide pipe; the compressor and the buffer tank are connected by a gas guide pipe;

[0009] The six adsorption towers are composed of A tower, B tower, C tower, D tower, E tower, and F tower.

[0010] The six adsorption towers are respectively communicated with the buffer tank through six gas inlet pipes, and a corresponding gas inlet valve is arranged on each gas inlet pipe;

[0011] The six adsorption towers are respectively communicated with the waste gas tank through six waste gas pipes, and a corresponding waste gas tank gas outlet valve is arranged on each waste gas pipe;

[0012] The six adsorption towers are respectively communicated with the product tank through six gas outlet pipes, and a corresponding product gas outlet valve is arranged on each gas outlet pipe;

[0013] The six adsorption towers are respectively communicated with each other through a flow pipe, and two flow valves are arranged side by side on the flow pipe corresponding to the six adsorption towers;

[0014] The pressure transmitters are respectively arranged in the buffer tank and the six adsorption towers;

[0015] The concentration transmitters are respectively arranged in the buffer tank, the waste gas tank, and the product tank;

[0016] The temperature transmitters are respectively arranged outside the six adsorption towers;

[0017] The low-concentration coalbed methane explosion suppression type concentration control method is performed according to the following steps:

[0018] Step 1, the PLC controller sends a start signal to the pressure swing adsorption system, and the pressure swing adsorption system opens the total valve according to the start signal, so that the compressor works and starts to pressurize the gas in the raw material tank, so as to send the pressurized gas into the buffer tank;

[0019] Step 2, the PLC controller collects the pressure value β of the buffer tank by using the pressure sensor, and judges whether the pressure value β reaches the specified range; if yes, step 3 is executed; otherwise, step 9 is executed;

[0020] Step 3, the PLC controller controls the current power of the compressor to remain unchanged, and opens the gas inlet valve of the A tower for charging the A tower;

[0021] Step 4, record the opening time point T of the gas inlet valve on the gas inlet pipe of the A towerA0 and the gas inlet time T of the A tower A , so as to obtain the time t required for the gas to reach the A tower A = T A -T A0 , and calculate the adsorption time t of the A tower to the adsorbate; wherein, represents the axial distance between the adsorbent particles, represents the formation porosity of the adsorbent in the A tower, represents the gas flow rate in the A tower, represents the time when the adsorbent particles enter the A tower and start to contact with the solution, represents the time when the gas reaches the A tower, the gas inlet time T A refers to the time point when the pressure signal P(A) of the A tower is detected by the pressure sensor;

[0022] Step 5, the PLC controller judges whether the pressure signal P(A) of the A tower reaches the optimal adsorption pressure a; if yes, step 6 is executed; otherwise, the current power of the compressor is increased and the A tower is continuously aerated, and step 4 is executed;

[0023] Step 6, the PLC controller judges whether the adsorption time t A0 of the A tower reaches the set time t max ; if yes, step 7 is executed; otherwise, it is judged whether the change fluctuation range of the pressure signal P(A) within the adsorption time t A0 exceeds the threshold value; if yes, it indicates that the product gas outlet valve on the gas outlet pipe of the A tower or the air tightness of the A tower is insufficient, and step 34 is executed; otherwise, step 7 is executed;

[0024] Step 7, the PLC controller controls the relay to open the waste gas tank outlet valve, and detects the A tower exhaust gas by using the concentration transmitter of the waste gas tank, and executes step 8;

[0025] Step 8, it is judged whether the waste gas tank A tower exhaust gas concentration is within the set adsorption tower concentration change range; if yes, the waste gas tank outlet valve is closed and step 10 is executed; otherwise, the waste gas tank outlet valve is closed, and the adsorption time t A0 is added by ×t A0 , and then step 6 is returned for sequential execution; represents a multiple between 0 and 1;

[0026] Step 9, it is judged whether the pressure in the buffer tank reaches the set value within the starting working time Δt of the compressor; if yes, step 3 is executed; otherwise, the working power of the compressor is increased, and step 3 is executed;

[0027] Step 10, six adsorption towers carry out A tower adsorption cycle work:

[0028] The PLC controller controls the air inlet valve of the A tower to open, so that the A tower inhales air, and controls the product gas outlet valve of the A tower to open, so that the A tower discharges product gas;

[0029] The PLC controller controls the flow valve of the F tower and the flow valve of the B tower to open respectively, so as to pressurize the B tower;

[0030] The PLC controller controls the flow valve of the E tower and the flow valve of the C tower to open respectively, so as to pressurize the C tower;

[0031] The PLC controller controls the exhaust tank outlet valve of the D tower to open, so that the D tower discharges exhaust gas;

[0032] The PLC controller controls the exhaust tank outlet valve of the D tower, the flow valve of the E tower, the flow valve of the C tower, the flow valve of the F tower, the flow valve of the B tower, the product gas outlet valve of the A tower, and the air inlet valve of the A tower to close after a set time value ;

[0033] Step 11, whether the valves in step 10 are closed after a set time value , if yes, step 12 is executed; otherwise, step 34 is executed;

[0034] Step 12, six adsorption towers carry out B tower pressurization cycle work:

[0035] The PLC controller controls the air inlet valve of the A tower to open, so that the A tower inhales air, and controls the product gas outlet valve of the A tower to open, so that the A tower discharges product gas;

[0036] The PLC controller controls the product gas outlet valve of the B tower to open, so as to pressurize the B tower;

[0037] The PLC controller controls the flow valve of the F tower and the flow valve of the C tower to open respectively, so as to pressurize the C tower;

[0038] The PLC controller controls the flow valve of the E tower and the flow valve of the D tower to open respectively, so as to flush the D tower;

[0039] The PLC controller controls the flow valve of the E tower, the flow valve of the D tower, the flow valve of the F tower, the flow valve of the C tower, the product gas outlet valve of the B tower, the product gas outlet valve of the A tower, and the air inlet valve of the A tower to close after a set time value ;

[0040] Step 13, judging whether the valves in step 12 are closed in a set time value If yes, step 14 is executed; otherwise, step 34 is executed.

[0041] Step 14, six adsorption towers are operated in a B tower adsorption cycle:

[0042] The PLC controller controls the flow-through valves of the A tower and the C tower to be opened respectively, for pressurizing the C tower.

[0043] The PLC controller controls the gas inlet valve of the B tower to be opened, so that the B tower is supplied with gas, and controls the product gas outlet valve of the B tower to be opened, so that the B tower is discharged with product gas.

[0044] The PLC controller controls the flow-through valves of the F tower and the D tower to be opened respectively, for pressurizing the D tower.

[0045] The PLC controller controls the waste gas tank outlet valve of the E tower to be opened, so that the E tower is discharged with waste gas.

[0046] The PLC controller controls the waste gas tank outlet valve of the E tower, the flow-through valves of the F tower and the D tower, the product gas outlet valve of the B tower, the gas inlet valve of the B tower, the flow-through valves of the A tower and the C tower to be closed in a set time value afterwards.

[0047] Step 15, judging whether the valves in step 14 are closed in a set time value afterwards, step 16 is executed; otherwise, step 34 is executed.

[0048] Step 16, six adsorption towers are operated in a C tower pressurization cycle:

[0049] The PLC controller controls the flow-through valves of the A tower and the D tower to be opened respectively, for pressurizing the D tower.

[0050] The PLC controller controls the gas inlet valve of the B tower to be opened, so that the B tower is supplied with gas, and controls the product gas outlet valve of the B tower to be opened, so that the B tower is discharged with product gas.

[0051] The PLC controller controls the product gas outlet valve of the C tower to be opened, for pressurizing the C tower.

[0052] The PLC controller controls the flow-through valves of the F tower and the E tower to be opened respectively, for flushing the E tower.

[0053] The PLC controller controls the flow valve of the F tower, the flow valve of the E tower, the product gas outlet valve of the C tower, the product gas outlet valve of the B tower, the gas inlet valve of the B tower, the flow valve of the A tower and the flow valve of the D tower to be closed at a set time value and then all are closed;

[0054] Step 17, it is judged whether the valves in step 16 are all closed at a set time value If yes, step 18 is executed; otherwise, step 34 is executed.

[0055] Step 18, the six adsorption towers perform C tower adsorption cycle work:

[0056] The PLC controller controls the flow valve of the A tower and the flow valve of the E tower to be opened for pressurizing the E tower.

[0057] The PLC controller controls the flow valve of the B tower and the flow valve of the D tower to be opened for pressurizing the D tower.

[0058] The PLC controller controls the gas inlet valve of the C tower to be opened so that the C tower takes in gas, and controls the product gas outlet valve of the C tower to be opened so that the C tower discharges product gas.

[0059] The PLC controller controls the waste gas tank outlet valve of the F tower to be opened for discharging gas from the F tower.

[0060] The PLC controller controls the waste gas tank outlet valve of the F tower, the product gas outlet valve of the C tower, the gas inlet valve of the C tower, the flow valve of the B tower, the flow valve of the D tower, the flow valve of the A tower and the flow valve of the E tower to be closed at a set time value and then all are closed.

[0061] Step 19, it is judged whether the valves in step 18 are all closed at a set time value If yes, step 20 is executed; otherwise, step 34 is executed.

[0062] Step 20, the six adsorption towers perform D tower pressurization cycle work:

[0063] The PLC controller controls the flow valve of the A tower and the flow valve of the F tower to be opened for flushing the F tower.

[0064] The PLC controller controls the flow valve of the B tower and the flow valve of the E tower to be opened for pressurizing the E tower.

[0065] The PLC controller controls the gas inlet valve of the C tower to be opened so that the C tower takes in gas, and controls the product gas outlet valve of the C tower to be opened so that the C tower discharges product gas.

[0066] The PLC controller controls the product gas outlet valve of the D tower to open, so that the D tower is pressurized;

[0067] The PLC controller controls the product gas outlet valve of the D tower, the product gas outlet valve of the C tower, the gas inlet valve of the C tower, the flow valve of the B tower, the flow valve of the E tower, the flow valve of the A tower, and the flow valve of the F tower to close at a set time value

[0068] Step 21, whether the valves in step 20 are all closed at a set time value Step 22 is executed if they are closed, otherwise step 34 is executed;

[0069] Step 22, the six adsorption towers perform D tower adsorption cycle work:

[0070] The PLC controller controls the waste gas tank outlet valve of the A tower to open, for venting the A tower;

[0071] The PLC controller controls the flow valve of the B tower and the flow valve of the F tower to open, for pressurizing the F tower;

[0072] The PLC controller controls the flow valve of the C tower and the flow valve of the E tower to open, for pressurizing the E tower;

[0073] The PLC controller controls the gas inlet valve of the D tower to open, so that the D tower is pressurized, and controls the product gas outlet valve of the D tower to open, so that the D tower is pressurized;

[0074] The PLC controller controls the product gas outlet valve of the D tower, the gas inlet valve of the D tower, the flow valve of the C tower, the flow valve of the E tower, the flow valve of the B tower, the flow valve of the F tower, and the waste gas tank outlet valve of the A tower to close at a set time value

[0075] Step 23, whether the valves in step 22 are all closed at a set time value Step 24 is executed if they are closed, otherwise step 34 is executed;

[0076] Step 24, the six adsorption towers perform E tower pressurization cycle work:

[0077] The PLC controller controls the flow valve of the B tower and the flow valve of the A tower to open, for flushing the A tower;

[0078] The PLC controller controls the flow valve of the C tower and the flow valve of the F tower to open, for pressurizing the F tower;

[0079] ​​The PLC controller controls the product gas outlet valve of the E tower to open, so that the E tower discharges product gas;

[0080] The PLC controller controls the product gas outlet valve of the E tower to open, so that the E tower discharges product gas;

[0081] The PLC controller controls the product gas outlet valve of the E tower, the product gas outlet valve of the D tower, the inlet valve of the D tower, the flow valve of the C tower, the flow valve of the F tower, the flow valve of the B tower, and the flow valve of the A tower to close at a set time value ;

[0082] Step 25, whether the valves in step 24 are all closed at a set time value , if yes, step 26 is executed; otherwise, step 34 is executed;

[0083] Step 26, the six adsorption towers perform E tower adsorption cycle work:

[0084] The PLC controller controls the flow valve of the C tower and the flow valve of the A tower to open, so as to charge the A tower;

[0085] The PLC controller controls the waste gas tank outlet valve of the B tower to open, so as to discharge the B tower;

[0086] The PLC controller controls the flow valve of the D tower and the flow valve of the F tower to open, so as to charge the F tower;

[0087] The PLC controller controls the product gas outlet valve of the E tower to open, so that the E tower discharges product gas;

[0088] The PLC controller controls the product gas outlet valve of the E tower, the inlet valve of the E tower, the flow valve of the D tower, the flow valve of the F tower, the waste gas tank outlet valve of the B tower, the flow valve of the C tower, and the flow valve of the A tower to close at a set time value ;

[0089] Step 27, whether the valves in step 26 are all closed at a set time value , if yes, step 28 is executed; otherwise, step 34 is executed;

[0090] Step 28, the six adsorption towers perform F tower charging cycle work:

[0091] The PLC controller controls the flow valve of the D tower and the flow valve of the A tower to open, so as to charge the A tower;

[0092] The PLC controller controls the flow valve of the C tower and the flow valve of the B tower to open respectively, for flushing the B tower;

[0093] The PLC controller controls the product gas outlet valve of the E tower to open, so that the E tower discharges product gas;

[0094] The PLC controller controls the product gas outlet valve of the F tower to open, so that the F tower is pressurized;

[0095] The PLC controller controls the flow valve of the D tower, the flow valve of the A tower, the flow valve of the C tower, the flow valve of the B tower, the product gas outlet valve of the E tower, the inlet valve of the E tower, and the product gas outlet valve of the F tower to close respectively after a set time value ;

[0096] Step 29, whether the valves in step 28 are closed after a set time value , if yes, step 30 is executed; otherwise, step 34 is executed;

[0097] Step 30, the six adsorption towers are subjected to F tower adsorption cycle work:

[0098] The PLC controller controls the flow valve of the E tower and the flow valve of the A tower to open respectively, for pressurizing the A tower;

[0099] The PLC controller controls the flow valve of the D tower and the flow valve of the B tower to open respectively, for pressurizing the B tower;

[0100] The PLC controller controls the waste tank outlet valve of the C tower to open, for exhausting the C tower;

[0101] The PLC controller controls the inlet valve of the F tower to open, so that the F tower is pressurized, and controls the product gas outlet valve of the F tower to open, so that the F tower discharges product gas;

[0102] The PLC controller controls the product gas outlet valve of the F tower, the inlet valve of the F tower, the waste tank outlet valve of the C tower, the flow valve of the D tower, the flow valve of the B tower, the flow valve of the E tower, and the flow valve of the A tower to close respectively after a set time value ;

[0103] Step 31, whether the valves in step 30 are closed after a set time value , if yes, step 32 is executed; otherwise, step 34 is executed;

[0104] Step 32, the six adsorption towers are subjected to A tower pressurization cycle work:

[0105] The PLC controller controls the product gas outlet valve of the A tower to open, so that the A tower is pressurized.

[0106] The PLC controller controls the product gas outlet valve of the A tower to open, so that the A tower is pressurized.

[0107] The PLC controller controls the flow valve of the E tower and the flow valve of the B tower to open respectively, so as to pressurize the B tower.

[0108] The PLC controller controls the flow valve of the D tower and the flow valve of the C tower to open respectively, so as to flush the C tower.

[0109] The PLC controller controls the product gas outlet valve of the F tower, the inlet valve of the F tower, the product gas outlet valve of the A tower, the flow valve of the E tower, the flow valve of the B tower, the flow valve of the D tower, and the flow valve of the C tower to close at a set time value after all the valves are closed.

[0110] Step 33, whether the valves in step 32 are closed at a set time value after all the valves are closed, if yes, step 10 is executed; otherwise, step 34 is executed.

[0111] Step 34, all the valves are closed and the control is stopped, and an abnormal signal is transmitted to the alarm module for alarm.

[0112] Step 35, whether the gas production in the product tank is lower than the target production L; if yes, step 10 is executed; if not, it means that the concentration of the low-concentration gas is increased, and the work is stopped.

[0113] The electronic device comprises a memory and a processor, and the memory is used for storing a program supporting the processor to execute the low-concentration coal seam gas explosion suppression type concentration control method, and the processor is configured to execute the program stored in the memory.

[0114] The computer readable storage medium stores a computer program, and the computer program is executed by the processor to execute the steps of the low-concentration coal seam gas explosion suppression type concentration control method.

[0115] Compared with the prior art, the low-concentration coal seam gas explosion suppression type concentration control method has the following beneficial effects:

[0116] The application realizes remote monitoring and adjustment of valve switching and gas concentration in pressure swing adsorption, so as to judge whether the equipment can normally run and make corresponding adjustment, realizes remote control, and does not need personnel to operate on site, solves the smooth running of complex process, and further guarantees the safety of the site. BRIEF DESCRIPTION OF DRAWINGS

[0117] Figure 1 The figure is a structural schematic diagram of the explosion-suppressed concentration-raising control method of the application;

[0118] Figure 2 The figure is a pressure swing adsorption flow chart of the explosion-suppressed concentration-raising control method of the application;

[0119] In the figure, 1 is a raw material tank; 2 is a buffer tank; 3 is a waste gas tank; 4 is a product tank; 5 is a compressor; 001 is a total valve; a1 is a product gas outlet valve of the A tower; a2 is a flow valve of the A tower; a3 is a flow valve of the A tower; a4 is an air inlet valve of the A tower; a5 is a waste gas tank outlet valve of the A tower; b1 is a product gas outlet valve of the B tower; b2 is a flow valve of the B tower; b3 is a flow valve of the B tower; b4 is an air inlet valve of the B tower; b5 is a waste gas tank outlet valve of the B tower; c1 is a product gas outlet valve of the C tower; c2 is a flow valve of the C tower; c3 is a flow valve of the C tower; c4 is an air inlet valve of the C tower; c5 is a waste gas tank outlet valve of the C tower; d1 is a product gas outlet valve of the D tower; d2 is a flow valve of the D tower; d3 is a flow valve of the D tower; d4 is an air inlet valve of the D tower; d5 is a waste gas tank outlet valve of the D tower; e1 is a product gas outlet valve of the E tower; e2 is a flow valve of the E tower; e3 is a flow valve of the E tower; e4 is an air inlet valve of the E tower; e5 is a waste gas tank outlet valve of the E tower; f1 is a product gas outlet valve of the F tower; f2 is a flow valve of the F tower; f3 is a flow valve of the F tower; f4 is an air inlet valve of the F tower; and f5 is a waste gas tank outlet valve of the F tower. DETAILED DESCRIPTION

[0120] The application is further described below in combination with the drawings and examples.

[0121] In the embodiment, the explosion-suppressed concentration-raising control method based on PLC is applied to a control system for explosion-suppressed concentration-raising of low-concentration coal bed gas, and the control system comprises a PLC controller, a compressor 5, a total valve 001, a plurality of valves, a pressure swing adsorption system, a plurality of relays, an alarm module, a pressure transmitter, a temperature transmitter, and a concentration transmitter.

[0122] The pressure swing adsorption system comprises a raw material tank 1, a buffer tank 2, six adsorption towers, a waste gas tank 3, and a product tank 4.

[0123] A total valve 001 is arranged between the raw material tank 1 and the compressor 5 and connected through an air guide pipe; the compressor 5 and the buffer tank 4 are connected through an air guide pipe; the specific connection diagram is shown in Figure 1 ;

[0124] The six adsorption towers are composed of an A tower, a B tower, a C tower, a D tower, an E tower and an F tower;

[0125] The six adsorption towers are respectively communicated with the buffer tank 2 through six air inlet pipes, and a corresponding air inlet valve is arranged on each air inlet pipe;

[0126] The six adsorption towers are respectively communicated with the waste gas tank 3 through six waste gas pipes, and a corresponding waste gas tank outlet valve is arranged on each waste gas pipe;

[0127] The six adsorption towers are respectively communicated with the product tank 4 through six air outlet pipes, and a corresponding product gas outlet valve is arranged on each air outlet pipe;

[0128] The six adsorption towers are respectively communicated with each other through a flow pipe, and two flow valves are arranged in parallel on the flow pipe corresponding to the six adsorption towers; the flow valve is used to connect two towers during pressure swing adsorption, so that the two towers are pressurized and flushed;

[0129] The pressure transmitters are respectively arranged in the buffer tank 2 and the six adsorption towers;

[0130] The concentration transmitters are respectively arranged in the buffer tank 2, the waste gas tank 3 and the product tank 4; during the working process, the pressure of the raw material gas is transmitted to the PLC system through the pressure transmitters and the concentration transmitters through the analog signal receiver, and the pressure and concentration in the adsorption tower are obtained through the processing of the data;

[0131] The temperature transmitters are respectively arranged on the outside of the six adsorption towers; the temperature transmitters can detect the temperature of the equipment during operation, and prevent the danger caused by the too high temperature of the system;

[0132] In this embodiment, the low-concentration coal bed gas explosion suppression type concentration control method is performed according to the following steps:

[0133] Step 1, the PLC controller sends a start signal to the pressure swing adsorption system, and the pressure swing adsorption system opens the total valve 001 according to the start signal, so that the compressor 5 works and starts to pressurize the gas in the raw material tank 1, so as to send the pressurized gas into the buffer tank 2;

[0134] Step 2, the PLC controller collects the pressure value of the buffer tank 2 by using the pressure sensor, and judges whether the pressure value reaches the specified range; if yes, step 3 is executed; otherwise, step 9 is executed;

[0135] Step 3, the PLC controller controls the current power of the compressor 5 to remain unchanged, and opens the inlet valve a4 of the A tower for charging the A tower;

[0136] Step 4, record the opening time point T of the inlet valve a4 on the inlet pipe of the A tower A0 , and the inlet time T of the A tower A , so as to obtain the time t required for the gas to reach the A tower A =T A -T A0 , and calculate the adsorption time of the A tower to the adsorbate ; wherein, represents the axial distance between the adsorbent particles, represents the formation porosity of the adsorbent in the A tower, represents the gas flow rate in the A tower, represents the time when the adsorbent particles enter the tower and start to contact with the solution, represents the time when the gas reaches the A tower, the inlet time T A refers to the time point when the pressure signal PA of the A tower is detected by the pressure sensor;

[0137] Step 5, the PLC controller judges whether the pressure signal PA of the A tower reaches the optimal adsorption pressure; if so, step 6 is executed; otherwise, the current power of the compressor 5 is increased and the charging of the A tower is continued; step 4 is executed;

[0138] Step 6, the PLC controller judges whether the adsorption time t A0 of the A tower reaches the set time t max ; if so, step 7 is executed; otherwise, it is judged whether the change fluctuation range of the pressure signal PA within the adsorption time t A0 exceeds the threshold value; if so, it indicates that the product gas outlet valve a1 on the outlet pipe of the A tower or the air tightness of the A tower is insufficient, and step 34 is executed; otherwise, step 7 is executed;

[0139] Step 7, the PLC controller controls the relay to open the waste gas tank 3 outlet valve a5, and detects the A tower exhaust gas by using the concentration transmitter of the waste gas tank 3, and executes step 8;

[0140] Step 8, it is judged whether the A tower exhaust gas concentration of the waste gas tank 3 is within the set adsorption tower concentration change range; if so, the waste gas tank outlet valve a5 is closed and step 10 is executed; otherwise, the waste gas tank 3 outlet valve a5 is closed, and the adsorption time t A0 is added by ×t A0 , and then returns to step 6 for sequential execution; represents a multiple between 0 and 1;

[0141] Step 9, judge whether the pressure in the buffer tank 2 reaches the set value within the compressor 5 starting working time Δt, if yes, execute step 3; otherwise, increase the working power of the compressor 5, and execute step 3;

[0142] Step 10, six adsorption towers perform A tower adsorption cycle work:

[0143] The PLC controller controls the air inlet valve a4 of the A tower to open, so that the A tower inhales air, and controls the product gas outlet valve a1 of the A tower to open, so that the A tower discharges product gas;

[0144] The PLC controller controls the flow valve f3 of the F tower and the flow valve b3 of the B tower to open respectively, for pressurizing the B tower;

[0145] The PLC controller controls the flow valve e2 of the E tower and the flow valve c2 of the C tower to open respectively, for pressurizing the C tower;

[0146] The PLC controller controls the waste gas tank outlet valve d5 of the D tower to open, so that the D tower discharges waste gas;

[0147] The PLC controller controls the waste gas tank outlet valve d5 of the D tower, the flow valve e2 of the E tower, the flow valve c2 of the C tower, the flow valve f3 of the F tower, the flow valve b3 of the B tower, the product gas outlet valve a1 of the A tower, and the air inlet valve a4 of the A tower to close at the set time value ;

[0148] Step 11, judge whether the valves in step 10 are all closed at the set time value ; if yes, execute step 12; otherwise, execute step 34;

[0149] Step 12, six adsorption towers perform B tower pressurization cycle work:

[0150] The PLC controller controls the air inlet valve a4 of the A tower to open, so that the A tower inhales air, and controls the product gas outlet valve a1 of the A tower to open, so that the A tower discharges product gas;

[0151] The PLC controller controls the product gas outlet valve b1 of the B tower to open, for pressurizing the B tower;

[0152] The PLC controller controls the flow valve f3 of the F tower and the flow valve c3 of the C tower to open respectively, for pressurizing the C tower;

[0153] The PLC controller controls the flow valve e2 of the E tower and the flow valve d2 of the D tower to open respectively, for flushing the D tower;

[0154] The PLC controller controls the flow valve e2 of the E tower, the flow valve d2 of the D tower, the flow valve f3 of the F tower, the flow valve c3 of the C tower, the product gas outlet valve b1 of the B tower, the product gas outlet valve a1 of the A tower, and the inlet valve a4 of the A tower to be closed at a set time value and then all are closed;

[0155] Step 13, it is judged whether the valves in step 12 are all closed at a set time value If yes, step 14 is executed; otherwise, step 34 is executed.

[0156] Step 14, the six adsorption towers perform a B tower adsorption cycle:

[0157] The PLC controller controls the flow valve a2 of the A tower and the flow valve c2 of the C tower to be opened for pressurizing the C tower.

[0158] The PLC controller controls the inlet valve b4 of the B tower to be opened for the B tower to intake air, and controls the product gas outlet valve b1 of the B tower to be opened for the B tower to output product gas.

[0159] The PLC controller controls the flow valve f3 of the F tower and the flow valve d3 of the D tower to be opened for pressurizing the D tower.

[0160] The PLC controller controls the waste gas tank outlet valve e5 of the E tower to be opened for the E tower to discharge waste gas.

[0161] The PLC controller controls the waste gas tank outlet valve e5 of the E tower, the flow valve f3 of the F tower, the flow valve d3 of the D tower, the product gas outlet valve b1 of the B tower, the inlet valve b4 of the B tower, the flow valve a2 of the A tower, and the flow valve c2 of the C tower to be closed at a set time value and then all are closed.

[0162] Step 15, it is judged whether the valves in step 14 are all closed at a set time value If yes, step 16 is executed; otherwise, step 34 is executed.

[0163] Step 16, the six adsorption towers perform a C tower pressurization cycle:

[0164] The PLC controller controls the flow valve a3 of the A tower and the flow valve d3 of the D tower to be opened for pressurizing the D tower.

[0165] The PLC controller controls the inlet valve b4 of the B tower to be opened for the B tower to intake air, and controls the product gas outlet valve b1 of the B tower to be opened for the B tower to output product gas.

[0166] The PLC controller controls the product gas outlet valve c1 of the C tower to open, for pressurizing the C tower;

[0167] The PLC controller controls the flow valve f2 of the F tower and the flow valve e2 of the E tower to open respectively, for flushing the E tower;

[0168] The PLC controller controls the flow valve f2 of the F tower, the flow valve e2 of the E tower, the product gas outlet valve c1 of the C tower, the product gas outlet valve b1 of the B tower, the gas inlet valve b4 of the B tower, the flow valve a3 of the A tower, and the flow valve d3 of the D tower to close respectively in a set time value ;

[0169] Step 17, whether the valves in step 16 are all closed in a set time value , if yes, step 18 is executed; otherwise, step 34 is executed;

[0170] Step 18, the six adsorption towers perform C tower adsorption cycle work:

[0171] The PLC controller controls the flow valve a3 of the A tower and the flow valve e3 of the E tower to open respectively, for pressurizing the E tower;

[0172] The PLC controller controls the flow valve b2 of the B tower and the flow valve d2 of the D tower to open respectively, for pressurizing the D tower;

[0173] The PLC controller controls the gas inlet valve c4 of the C tower to open, so that the C tower is supplied with gas, and controls the product gas outlet valve c1 of the C tower to open, so that the C tower is discharged with product gas;

[0174] The PLC controller controls the waste gas tank outlet valve f5 of the F tower to open, for discharging the F tower;

[0175] The PLC controller controls the waste gas tank outlet valve f5 of the F tower, the product gas outlet valve c1 of the C tower, the gas inlet valve c4 of the C tower, the flow valve b2 of the B tower, the flow valve d2 of the D tower, the flow valve a3 of the A tower, and the flow valve e3 of the E tower to close respectively in a set time value ;

[0176] Step 19, whether the valves in step 18 are all closed in a set time value , if yes, step 20 is executed; otherwise, step 34 is executed;

[0177] Step 20, the six adsorption towers perform D tower pressurization cycle work:

[0178] The PLC controller controls the flow valve a2 of the A tower and the flow valve f2 of the F tower to open respectively, for flushing the F tower;

[0179] The PLC controller controls the flow valve b3 of the B tower and the flow valve e3 of the E tower to open respectively, for charging pressure to the E tower;

[0180] The PLC controller controls the gas inlet valve c4 of the C tower to open, so that the C tower takes in gas, and controls the product gas outlet valve c1 of the C tower to open, so that the C tower discharges product gas;

[0181] The PLC controller controls the product gas outlet valve d1 of the D tower to open, so that the D tower is charged with pressure;

[0182] The PLC controller controls the product gas outlet valve d1 of the D tower, the product gas outlet valve c1 of the C tower, the gas inlet valve c4 of the C tower, the flow valve b3 of the B tower, the flow valve e3 of the E tower, the flow valve a2 of the A tower, and the flow valve f2 of the F tower to close respectively after a set time value ;

[0183] Step 21, whether the valves in step 20 are all closed after a set time value , if yes, step 22 is executed; otherwise, step 34 is executed;

[0184] Step 22, the six adsorption towers perform D tower adsorption cycle work:

[0185] The PLC controller controls the waste gas tank outlet valve a5 of the A tower to open, for discharging gas from the A tower;

[0186] The PLC controller controls the flow valve b3 of the B tower and the flow valve f3 of the F tower to open respectively, for charging pressure to the F tower;

[0187] The PLC controller controls the flow valve c2 of the C tower and the flow valve e2 of the E tower to open respectively, for charging pressure to the E tower;

[0188] The PLC controller controls the gas inlet valve d4 of the D tower to open, so that the D tower takes in gas, and controls the product gas outlet valve d1 of the D tower to open, so that the D tower discharges product gas;

[0189] The PLC controller controls the product gas outlet valve d1 of the D tower, the gas inlet valve d4 of the D tower, the flow valve c2 of the C tower, the flow valve e2 of the E tower, the flow valve b3 of the B tower, the flow valve f3 of the F tower, and the waste gas tank outlet valve a5 of the A tower to close respectively after a set time value ;

[0190] Step 23, whether the valves in step 22 are all closed after a set time value , if yes, step 24 is executed; otherwise, step 34 is executed;

[0191] Step 24, six adsorption towers carry out E tower pressurization cycle work:

[0192] The PLC controller controls the flow valve b2 of the B tower and the flow valve a2 of the A tower to open respectively, which is used to flush the A tower;

[0193] The PLC controller controls the flow valve c3 of the C tower and the flow valve f3 of the F tower to open respectively, which is used to pressurize the F tower;

[0194] The PLC controller controls the air inlet valve d4 of the D tower to open, so that the D tower inhales air, and controls the product gas outlet valve d1 of the D tower to open, so that the D tower discharges product gas;

[0195] The PLC controller controls the product gas outlet valve e1 of the E tower to open, so that the E tower is pressurized;

[0196] The PLC controller controls the product gas outlet valve e1 of the E tower, the product gas outlet valve d1 of the D tower, the air inlet valve d4 of the D tower, the flow valve c3 of the C tower, the flow valve f3 of the F tower, the flow valve b2 of the B tower, and the flow valve a2 of the A tower to close respectively after a set time value ;

[0197] Step 25, whether the valves in step 24 are closed after a set time value , if yes, step 26 is executed; otherwise, step 34 is executed;

[0198] Step 26, six adsorption towers carry out E tower adsorption cycle work:

[0199] The PLC controller controls the flow valve c3 of the C tower and the flow valve a3 of the A tower to open respectively, which is used to pressurize the A tower;

[0200] The PLC controller controls the exhaust tank outlet valve b5 of the B tower to open, which is used to exhaust the B tower;

[0201] The PLC controller controls the flow valve d2 of the D tower and the flow valve f2 of the F tower to open respectively, which is used to pressurize the F tower;

[0202] The PLC controller controls the air inlet valve e4 of the E tower to open, so that the E tower inhales air, and controls the product gas outlet valve e1 of the E tower to open, so that the E tower discharges product gas;

[0203] The PLC controller controls the product gas outlet valve e1 of the E tower, the air inlet valve e4 of the E tower, the flow valve d2 of the D tower, the flow valve f2 of the F tower, the exhaust tank outlet valve b5 of the B tower, the flow valve c3 of the C tower, and the flow valve a3 of the A tower to close respectively after a set time value ;

[0204] Step 27, judging whether the valves in step 26 are all closed within a set time value If yes, step 28 is executed; otherwise, step 34 is executed.

[0205] Step 28, the six adsorption towers are operated in F-tower pressure charging cycle:

[0206] The PLC controller controls the flow valve d2 of D-tower and the flow valve a2 of A-tower to be opened respectively, for charging A-tower.

[0207] The PLC controller controls the flow valve c3 of C-tower and the flow valve b3 of B-tower to be opened respectively, for flushing B-tower.

[0208] The PLC controller controls the gas inlet valve e4 of E-tower to be opened, so that E-tower takes in gas, and controls the product gas outlet valve e1 of E-tower to be opened, so that E-tower discharges product gas.

[0209] The PLC controller controls the product gas outlet valve f1 of F-tower to be opened, so that F-tower is charged.

[0210] The PLC controller controls the flow valve d2 of D-tower, the flow valve a2 of A-tower, the flow valve c3 of C-tower, the flow valve b3 of B-tower, the product gas outlet valve e1 of E-tower, the gas inlet valve e4 of E-tower, and the product gas outlet valve f1 of F-tower to be closed within a set time value .

[0211] Step 29, judging whether the valves in step 28 are all closed within a set time value If yes, step 30 is executed; otherwise, step 34 is executed.

[0212] Step 30, the six adsorption towers are operated in F-tower adsorption cycle:

[0213] The PLC controller controls the flow valve e3 of E-tower and the flow valve a3 of A-tower to be opened respectively, for charging A-tower.

[0214] The PLC controller controls the flow valve d2 of D-tower and the flow valve b2 of B-tower to be opened respectively, for charging B-tower.

[0215] The PLC controller controls the exhaust tank outlet valve c5 of C-tower to be opened, for exhausting C-tower.

[0216] The PLC controller controls the gas inlet valve f4 of F-tower to be opened, so that F-tower takes in gas, and controls the product gas outlet valve f1 of F-tower to be opened, so that F-tower discharges product gas.

[0217] The PLC controller controls the product gas outlet valve f1 of the F tower, the gas inlet valve f4 of the F tower, the waste gas tank outlet valve c5 of the C tower, the flow valve d2 of the D tower, the flow valve b2 of the B tower, the flow valve e3 of the E tower, and the flow valve a3 of the A tower to be closed at a set time value and then all are closed;

[0218] Step 31: judging whether the valves in step 30 are all closed at a set time value If yes, step 32 is executed; otherwise, step 34 is executed.

[0219] Step 32: the six adsorption towers are operated in the A tower pressure charging cycle:

[0220] The PLC controller controls the gas inlet valve f4 of the F tower to be opened so that the F tower is supplied with gas, and controls the product gas outlet valve f1 of the F tower to be opened so that the F tower is discharged with product gas.

[0221] The PLC controller controls the product gas outlet valve a1 of the A tower to be opened so that the A tower is charged with pressure.

[0222] The PLC controller controls the flow valve e2 of the E tower and the flow valve b2 of the B tower to be opened so as to charge the B tower with pressure.

[0223] The PLC controller controls the flow valve d3 of the D tower and the flow valve c3 of the C tower to be opened so as to flush the C tower.

[0224] The PLC controller controls the product gas outlet valve f1 of the F tower, the gas inlet valve f4 of the F tower, the product gas outlet valve a1 of the A tower, the flow valve e2 of the E tower, the flow valve b2 of the B tower, the flow valve d3 of the D tower, and the flow valve c3 of the C tower to be closed at a set time value and then all are closed.

[0225] Step 33: judging whether the valves in step 32 are all closed at a set time value If yes, step 10 is executed; otherwise, step 34 is executed.

[0226] Step 34: all valves are closed and the control is stopped, and an abnormal signal is transmitted to the alarm module for alarm. This step is to close all the outlet valves of the pressure swing adsorption towers, and the inlet valve of the buffer tank 2 is closed at the same time, and the compressor 5 is stopped, which can effectively prevent the over-high pressure of the raw material gas and the leakage of high-concentration product gas.

[0227] Step 35: judging whether the gas production in the product tank 4 is lower than the target production L; if yes, step 10 is executed; otherwise, it indicates that the concentration of the low-concentration gas is completed, and the work is stopped.

[0228] In the embodiment, an electronic device includes a memory for storing a program supporting a processor to execute the low-concentration coal-bed gas explosion-suppression type concentration-raising control method and the processor configured to execute the program stored in the memory.

[0229] In the embodiment, a computer readable storage medium has a computer program stored thereon, and the computer program is executed by a processor to perform the steps of the low-concentration coal-bed gas explosion-suppression type concentration-raising control method.

Claims

1. A PLC-based low-concentration coal-bed gas explosion-suppression type concentration control method, characterized by, The application relates to a control system for explosion-suppression type concentration of low-concentration coal seam gas, and the control system comprises a PLC controller, a compressor (5), a total valve (001), a plurality of valves, a pressure swing adsorption system, a plurality of relays, an alarm module, a pressure transmitter, a temperature transmitter and a concentration transmitter. The pressure swing adsorption system comprises a raw material tank (1), a buffer tank (2), six adsorption towers, a waste gas tank (3) and a product tank (4). The total valve (001) is arranged between the raw material tank (1) and the compressor (5) and is connected through a gas guide pipe; the compressor (5) and the buffer tank (2) are connected through a gas guide pipe. The six adsorption towers are composed of an A tower, a B tower, a C tower, a D tower, an E tower and an F tower. The six adsorption towers are communicated with the buffer tank (2) through six gas inlet pipes, and corresponding gas inlet valves are arranged on the gas inlet pipes. The six adsorption towers are communicated with the waste gas tank (3) through six waste gas pipes, and corresponding waste gas tank gas outlet valves are arranged on the waste gas pipes. The six adsorption towers are communicated with the product tank (4) through six gas outlet pipes, and corresponding product gas outlet valves are arranged on the gas outlet pipes. The six adsorption towers are communicated with each other through six flow pipes, and two flow valves are arranged on the flow pipes corresponding to the six adsorption towers. The pressure transmitter is arranged in the buffer tank (2) and the six adsorption towers. The concentration transmitter is arranged in the buffer tank (2), the waste gas tank (3) and the product tank (4). The temperature transmitter is arranged outside the six adsorption towers. The low-concentration coal seam gas explosion-suppression type concentration control method is performed according to the following steps: Step 1: the PLC controller sends a starting signal to the pressure swing adsorption system, the pressure swing adsorption system opens the total valve (001) according to the starting signal, the compressor (5) works and starts to pressurize the gas in the raw material tank (1), and then the pressurized gas is sent into the buffer tank (2); Step 2: the PLC controller collects the pressure value beta of the buffer tank (2) by using a pressure sensor, and judges whether the pressure value beta reaches a specified range; if yes, step 3 is executed; otherwise, step 9 is executed; Step 3: the PLC controller controls the current power of the compressor (5) to remain unchanged, and opens the gas inlet valve (a4) of the A tower for charging the A tower; Step 4, record the opening time point T of the inlet valve (a4) on the inlet pipe of the A column A0 and the inlet time T of the A column A , so as to obtain the time t required for the gas to reach the A column A = T A -T A0 , and calculate the adsorption time of the A column to the adsorbate ; wherein, represents the axial distance between the adsorbent particles, represents the formation porosity of the adsorbent in the A column, represents the gas flow rate in the A column, represents the time when the adsorbent particles enter the A column and start to contact with the solution, represents the time when the gas reaches the A column, the inlet time T A refers to the time point when the pressure signal P(A) of the A column is detected by using the pressure sensor; Step 5: the PLC controller judges whether the pressure signal P(A) of the A tower reaches the optimal adsorption pressure alpha; if yes, step 6 is executed; otherwise, the current power of the compressor (5) is increased, the A tower is continuously charged, and step 4 is executed; Step 6: The PLC controller determines the adsorption time t of tower A. A0 Has the set time t been reached? max If the target is reached, proceed to step 7; otherwise, determine the adsorption time t. A0 If the fluctuation range of the pressure signal P(A) exceeds the threshold, it indicates that the product gas outlet valve (a1) on the outlet pipe of tower A or the air tightness of tower A is insufficient, and step 34 is executed; otherwise, step 7 is executed. Step 7: the PLC controller controls the relay to open the waste gas tank (3) gas outlet valve (a5), detects the exhaust gas of the A tower by using the concentration transmitter of the waste gas tank (3), and executes step 8; Step 8, determine whether the exhaust tank (3) A tower exhaust gas concentration in the set adsorption tower concentration range; if so, close the exhaust tank (3) outlet valve (a5) and execute step 10; otherwise, close the valve exhaust tank (3) outlet valve (a5), and the adsorption time t A0 Plus Xt A0 After that, return to step 6 in sequence; Indicates a multiple between 0 and 1; Step 9, judging whether the pressure in the buffer tank (2) reaches the set value within the starting time Δt of the compressor (5), if yes, executing step 3; otherwise, increasing the working power of the compressor (5) and executing step 3; Step 10, the six adsorption towers perform A-tower adsorption cycle work: The PLC controller controls the air inlet valve (a4) of the A-tower to open, so that the A-tower inhales air, and controls the product gas outlet valve (a1) of the A-tower to open, so that the A-tower discharges product gas; The PLC controller controls the flow valve (f3) of the F-tower and the flow valve (b3) of the B-tower to open respectively, for pressurizing the B-tower; The PLC controller controls the flow valve (e2) of the E-tower and the flow valve (c2) of the C-tower to open respectively, for pressurizing the C-tower; The PLC controller controls the waste gas tank outlet valve (d5) of the D-tower to open, so that the D-tower discharges waste gas; The PLC controller controls the exhaust outlet valve (d5) of the D column, the flow valve (e2) of the E column, the flow valve (c2) of the C column, the flow valve (f3) of the F column, the flow valve (b3) of the B column, the product gas outlet valve (a1) of the A column, and the inlet valve (a4) of the A column at a set time value and then all are closed. Step 11, determine if all valves in step 10 are closed at the set time value Step 12, if yes, then execute step 13; otherwise, execute step 14 Step 12, the six adsorption towers perform B-tower pressurization cycle work: The PLC controller controls the air inlet valve (a4) of the A-tower to open, so that the A-tower inhales air, and controls the product gas outlet valve (a1) of the A-tower to open, so that the A-tower discharges product gas; The PLC controller controls the product gas outlet valve (b1) of the B-tower to open, for pressurizing the B-tower; The PLC controller controls the flow valve (f3) of the F-tower and the flow valve (c3) of the C-tower to open respectively, for pressurizing the C-tower; The PLC controller controls the flow valve (e2) of the E-tower and the flow valve (d2) of the D-tower to open respectively, for flushing the D-tower; The PLC controller controls the flow valve (e2) of the E column, the flow valve (d2) of the D column, the flow valve (f3) of the F column, the flow valve (c3) of the C column, the product gas outlet valve (b1) of the B column, the product gas outlet valve (a1) of the A column, and the gas inlet valve (a4) of the A column at a set time value and then all are closed; Step 13, determine whether the valves in step 12 are all closed at the set time value Step 14, if yes, execute step 15; otherwise, execute step 34 Step 14, the six adsorption towers perform B-tower adsorption cycle work: The PLC controller controls the flow valve (a2) of the A-tower and the flow valve (c2) of the C-tower to open respectively, for pressurizing the C-tower; The PLC controller controls the air inlet valve (b4) of the B-tower to open, so that the B-tower inhales air, and controls the product gas outlet valve (b1) of the B-tower to open, so that the B-tower discharges product gas; The PLC controller controls the flow valve (f3) of the F-tower and the flow valve (d3) of the D-tower to open respectively, for pressurizing the D-tower; The PLC controller controls the waste gas tank outlet valve (e5) of the E-tower to open, so that the E-tower discharges waste gas; The PLC controller controls the exhaust outlet valve (e5) of the E column, the flow valve (f3) of the F column, the flow valve (d3) of the D column, the product gas outlet valve (b1) of the B column, the gas inlet valve (b4) of the B column, the flow valve (a2) of the A column, and the flow valve (c2) of the C column at a set time value and then all are closed. Step 15, determine if all valves in step 14 are closed at the set time value Step 16, if yes, then execute step 17; otherwise, execute step 18. Step 16, the six adsorption towers perform C-tower pressurization cycle work: The PLC controller controls the flow valve (a3) of the A-tower and the flow valve (d3) of the D-tower to open respectively, for pressurizing the D-tower; The PLC controller controls the air inlet valve (b4) of the B-tower to open, so that the B-tower inhales air, and controls the product gas outlet valve (b1) of the B-tower to open, so that the B-tower discharges product gas; The PLC controller controls the product gas outlet valve (c1) of the C-tower to open, for pressurizing the C-tower; The PLC controller controls the flow valve (f2) of the F-tower and the flow valve (e2) of the E-tower to open respectively, for flushing the E-tower; The PLC controller controls the flow valve (f2) of the F tower, the flow valve (e2) of the E tower, the product gas outlet valve (c1) of the C tower, the product gas outlet valve (b1) of the B tower, the gas inlet valve (b4) of the B tower, the flow valve (a3) of the A tower, and the flow valve (d3) of the D tower at a set time value and then all are closed; Step 17, determine if the valves in step 16 are all closed at the set time value Step 18, if yes, then execute step 19; otherwise, execute step 34. Step 18, the six adsorption towers perform C-tower adsorption cycle work: The PLC controller controls the flow valve (a3) of the A-tower and the flow valve (e3) of the E-tower to open respectively, for pressurizing the E-tower; The PLC controller controls the flow valve (b2) of the B tower and the flow valve (d2) of the D tower to open respectively, for charging pressure for the D tower; The PLC controller controls the gas inlet valve (c4) of the C tower to open, so that the C tower takes in gas, and controls the product gas outlet valve (c1) of the C tower to open, so that the C tower discharges product gas; The PLC controller controls the waste gas tank outlet valve (f5) of the F tower to open, for discharging gas from the F tower; The PLC controller controls the exhaust gas tank outlet valve (f5) of the F tower, the product gas outlet valve (c1) of the C tower, the gas inlet valve (c4) of the C tower, the flow valve (b2) of the B tower, the flow valve (d2) of the D tower, the flow valve (a3) of the A tower, and the flow valve (e3) of the E tower at a set time value after all are closed; Step 19, determine if all valves in step 18 are closed at the set time value Step 20, determine if all valves are closed at the set time value, if yes, execute step 21; otherwise, execute step 34 Step 20, the six adsorption towers perform D tower charging pressure cycle work: The PLC controller controls the flow valve (a2) of the A tower and the flow valve (f2) of the F tower to open respectively, for flushing the F tower; The PLC controller controls the flow valve (b3) of the B tower and the flow valve (e3) of the E tower to open respectively, for charging pressure for the E tower; The PLC controller controls the gas inlet valve (c4) of the C tower to open, so that the C tower takes in gas, and controls the product gas outlet valve (c1) of the C tower to open, so that the C tower discharges product gas; The PLC controller controls the product gas outlet valve (d1) of the D tower to open, so that the D tower charges pressure; The PLC controller controls the product gas outlet valve (d1) of the D column, the product gas outlet valve (c1) of the C column, the gas inlet valve (c4) of the C column, the flow valve (b3) of the B column, the flow valve (e3) of the E column, the flow valve (a2) of the A column, and the flow valve (f2) of the F column at a set time value and then all are closed. Step 21, determine whether the valves in step 20 are all closed at the set time value Step 22, determine whether the valves in step 21 are all closed at the set time value; if yes, execute step 23; otherwise, execute step 24 Step 22, the six adsorption towers perform D tower adsorption cycle work: The PLC controller controls the waste gas tank outlet valve (a5) of the A tower to open, for discharging gas from the A tower; The PLC controller controls the flow valve (b3) of the B tower and the flow valve (f3) of the F tower to open respectively, for charging pressure for the F tower; The PLC controller controls the flow valve (c2) of the C tower and the flow valve (e2) of the E tower to open respectively, for charging pressure for the E tower; The PLC controller controls the gas inlet valve (d4) of the D tower to open, so that the D tower takes in gas, and controls the product gas outlet valve (d1) of the D tower to open, so that the D tower discharges product gas; The PLC controller controls the product gas outlet valve (d1) of the D column, the gas inlet valve (d4) of the D column, the flow valve (c2) of the C column, the flow valve (e2) of the E column, the flow valve (b3) of the B column, the flow valve (f3) of the F column, and the waste gas tank outlet valve (a5) of the A column at a set time value after all are closed; Step 23, judging whether the valves in step 22 are all closed at the set time value Step 24, judging whether the valves in step 23 are all closed at the set time value; if yes, executing step 25; otherwise, executing step 34; Step 24, the six adsorption towers perform E tower charging pressure cycle work: The PLC controller controls the flow valve (b2) of the B tower and the flow valve (a2) of the A tower to open respectively, for flushing the A tower; The PLC controller controls the flow valve (c3) of the C tower and the flow valve (f3) of the F tower to open respectively, for charging pressure for the F tower; The PLC controller controls the gas inlet valve (d4) of the D tower to open, so that the D tower takes in gas, and controls the product gas outlet valve (d1) of the D tower to open, so that the D tower discharges product gas; The PLC controller controls the product gas outlet valve (e1) of the E tower to open, so that the E tower charges pressure; The PLC controller controls the product gas outlet valve (e1) of the E column, the product gas outlet valve (d1) of the D column, the gas inlet valve (d4) of the D column, the flow valve (c3) of the C column, the flow valve (f3) of the F column, the flow valve (b2) of the B column, and the flow valve (a2) of the A column at a set time value and then all are closed. Step 25, determine if the valves in step 24 are all closed at the set time value Step 26, if yes, then execute step 27; otherwise, execute step 28. Step 26, the six adsorption towers perform E tower adsorption cycle work: The PLC controller controls the flow valve (c3) of the C tower and the flow valve (a3) of the A tower to open respectively, for charging pressure for the A tower; The PLC controller controls the waste gas tank outlet valve (b5) of the B tower to open, for discharging gas from the B tower; The PLC controller controls the flow valve (d2) of the D tower and the flow valve (f2) of the F tower to open respectively, for charging pressure for the F tower; The PLC controller controls the gas inlet valve (e4) of the E tower to open, so that the E tower takes in gas, and controls the product gas outlet valve (e1) of the E tower to open, so that the E tower discharges product gas; The PLC controller controls the product gas outlet valve (e1) of the E column, the gas inlet valve (e4) of the E column, the flow valve (d2) of the D column, the flow valve (f2) of the F column, the waste gas tank outlet valve (b5) of the B column, the flow valve (c3) of the C column, and the flow valve (a3) of the A column at a set time value after all are closed; Step 27, determine whether the valves in step 26 are all closed at the set time value If yes, then execute step 28; otherwise, execute step 34. Step 28, six adsorption towers carry out F tower pressure charging cycle work: The PLC controller controls the flow valve (e3) of the E tower and the flow valve (a3) of the A tower to be opened respectively, for charging the A tower; The PLC controller controls the flow valve (d2) of the D tower and the flow valve (b3) of the B tower to be opened respectively, for flushing the B tower; The PLC controller controls the exhaust tank outlet valve (c5) of the C tower to be opened, for exhausting the C tower; The PLC controller controls the intake valve (f4) of the F tower to be opened, for the F tower to intake air, and controls the product gas outlet valve (f1) of the F tower to be opened, for the F tower to output product gas; The PLC controller controls the flow valve (d2) of the D column, the flow valve (a2) of the A column, the flow valve (c3) of the C column, the flow valve (b3) of the B column, the product gas outlet valve (e1) of the E column, the gas inlet valve (e4) of the E column, and the product gas outlet valve (f1) of the F column at a set time value after all are closed; Step 29, determine if all valves in step 28 are closed at the set time value Step 30, if all valves are closed, then execute step 31; otherwise, execute step 32. Step 32, six adsorption towers carry out A tower pressure charging cycle work: The PLC controller controls the intake valve (f4) of the F tower to be opened, for the F tower to intake air, and controls the product gas outlet valve (f1) of the F tower to be opened, for the F tower to output product gas; The PLC controller controls the product gas outlet valve (a1) of the A tower to be opened, for the A tower to charge pressure; The PLC controller controls the flow valve (e2) of the E tower and the flow valve (b2) of the B tower to be opened respectively, for charging the B tower; The PLC controller controls the flow valve (d3) of the D tower and the flow valve (c3) of the C tower to be opened respectively, for flushing the C tower; The PLC controller controls the product gas outlet valve (f1) of the F tower, the gas inlet valve (f4) of the F tower, the waste gas tank outlet valve (c5) of the C tower, the flow valve (d2) of the D tower, the flow valve (b2) of the B tower, the flow valve (e3) of the E tower, and the flow valve (a3) of the A tower at a set time value respectively, and then all are closed. Step 31, judging whether the valves in step 30 are all closed at the set time value Step 32, executing the next step if the valves are all closed; otherwise, executing step 34 Step 34, all valves are closed and the control is stopped, and an abnormal signal is transmitted to the alarm module for alarm; Step 35, it is judged whether the gas production in the product tank (4) is lower than the target production L; if yes, step 10 is executed; if not, it indicates that the concentration of low-concentration coal bed gas is increased, and the work is stopped. The memory is used for storing a program supporting the processor to execute the low-concentration coal bed gas explosion suppression type concentration control method of claim 1, and the processor is configured to execute the program stored in the memory. The computer program is executed by the processor to execute the steps of the low-concentration coal bed gas explosion suppression type concentration control method of claim 1. The computer program is executed by the processor to execute the steps of the low-concentration coal bed gas explosion suppression type concentration control method of claim 1. The PLC controller controls the product gas outlet valve (f1) of the F column, the inlet valve (f4) of the F column, the product gas outlet valve (a1) of the A column, the flow valve (e2) of the E column, the flow valve (b2) of the B column, the flow valve (d3) of the D column, and the flow valve (c3) of the C column at a set time value after all are closed; Step 33, judging whether the valves in step 32 are all closed at the set time value Step 34, judging whether the valves in step 33 are all closed at the set time value, if yes, executing step 10; otherwise, executing step 35 ​ ​ 2. An electronic device comprising a memory and a processor, characterized in that ​ 3. A computer-readable storage medium having stored thereon a computer program, characterized in that ​

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