A control method for energy-saving pressure swing adsorption gas production equipment

Abstract

The present invention relates to a control method for energy-saving pressure swing adsorption gas production equipment. Based on a control system, a first valve group of an adsorption unit, and a regulating valve, a first flowmeter, a second flowmeter, a gas purity analyzer, and a pressure gauge of a gas storage unit, the control method includes the following steps: the control system calculates the total flow Q passing through the second flowmeter in a set time period, and compares it with the total flow Q' passing through the second flowmeter in the previous set time period. When Q>Q', the control system controls the opening of the regulating valve according to the detection value of the first flowmeter, shortening the adsorption cycle of the adsorption unit until Q and Q' are equal; when Q=Q', the control system controls the opening of the regulating valve to remain unchanged; when Q<Q', the control system controls the opening of the regulating valve according to the detection value of the pressure gauge, extending the adsorption cycle of the adsorption unit until Q and Q' are equal. The control method can automatically adjust the operating parameters to the most energy-saving state according to the real-time gas consumption and ensure that the product gas meets the usage demand.

Description

Technical Field

[0001] The invention relates to a control method for energy-saving pressure swing adsorption gas production equipment. Background Art

[0002] In modern industry, pressure swing adsorption (PSA) gas production equipment is widely used for gas separation and preparation. PSA gas production equipment primarily utilizes the principle of adsorption by pressurizing an adsorbent and desorption by reducing pressure to adsorb and release other gases from air or other feed gases, thereby separating the target gas. The equipment operates when the actual gas production does not exceed the rated gas production capacity. The closer the actual gas production is to the rated gas production capacity, the lower the ratio of feed gas consumption to gas production, and the lower the equipment's operating energy consumption. Conversely, the lower the actual gas production is below the rated gas production capacity, the higher the ratio of feed gas consumption to gas production, and the higher the equipment's operating energy consumption. By using a flow meter to measure gas flow, when the actual gas production is lower than the rated gas production capacity, the adsorption and discharge cycles can be extended within a certain range to reduce air consumption, thereby reducing air compressor power consumption and achieving energy savings.

[0003] Previous energy-saving pressure swing adsorption gas production equipment was either manually adjusted or automatically adjusted in several gears, which could not achieve optimal energy saving. It was only suitable for situations where the gas consumption in the subsequent stage was stable and the gas consumption was decreasing. In this case, changing the gear to reasonably extend the adsorption cycle according to the changes in the gas consumption in the subsequent stage could achieve energy saving while ensuring purity. However, if the gas consumption in the subsequent stage suddenly increased, the adsorption cycle would suddenly change from long to short, which would inevitably lead to substandard gas purity in a short period of time and failure to meet usage requirements. If the adsorption cycle was slowly shortened and the flow rate was gradually increased, the pressure in the subsequent stage would drop again in a short period of time, and the product gas would be insufficient, which also failed to meet usage requirements. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a control method for energy-saving pressure swing adsorption gas production equipment, which can automatically adjust the operating parameters to the most energy-saving state according to the real-time gas consumption while ensuring that the product gas meets the usage demand.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A control method for energy-saving pressure swing adsorption gas production equipment, based on the control system,

[0007] Corresponding to the first valve group of the adsorption unit of the energy-saving pressure swing adsorption gas production equipment, the first valve group is controlled by the control system and is controlled to be opened or closed by the control system,

[0008] Corresponding to the second valve group, flow meter group, gas purity analyzer and pressure gauge of the gas storage unit of the energy-saving pressure swing adsorption gas production equipment, the gas storage unit includes a first gas tank and a second gas tank, the first gas tank is located between the adsorption unit and the second gas tank and is connected to the two, the second valve group includes a regulating valve arranged on the pipeline connecting the first gas tank and the second gas tank, the regulating valve is controlled by the control system and its opening is controlled by the control system, the flow meter group, gas purity analyzer and pressure gauge are respectively connected to the control system and feed back detection values ​​to the control system, the flow meter group includes a first flow meter arranged on the pipeline connecting the first gas tank and the second gas tank and a second flow meter arranged at the gas outlet end of the second gas tank, the pressure gauge is arranged on the second gas tank, and is used to detect the pressure in the second gas tank,

[0009] The control method includes:

[0010] (1) The control system calculates the total flow Q passing through the second flow meter in the set time period based on the detection value fed back by the second flow meter, and compares it with the total flow Q' passing through the second flow meter in the previous set time period. When Q>Q', execute (2); when Q=Q', execute (3); when Q<Q', execute (4);

[0011] (2) The control system controls the opening of the regulating valve according to the detection value of the first flow meter, so that the gas flow through the first flow meter increases slowly and the adsorption cycle of the adsorption unit is shortened until Q and Q' are equal;

[0012] (3) The control system controls the opening of the regulating valve to remain unchanged and fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer;

[0013] (4) The control system controls the opening of the regulating valve according to the detection value of the pressure gauge, so that the pressure in the second gas storage tank remains stable and the adsorption cycle of the adsorption unit is extended until Q and Q' are equal.

[0014] Because the gas pressure produced by the adsorption unit fluctuates, accompanied by periodic changes in flow rate, the installation of a first gas storage tank stabilizes both pressure and flow rate. When the downstream gas demand suddenly increases, the energy-saving PSA gas production equipment's gas output may be less than the gas demand within a short period of time, causing the adsorption cycle to abruptly shorten or even insufficient product gas. The installation of a second gas storage tank steadily lengthens the adsorption cycle and ensures uninterrupted gas supply to meet usage requirements.

[0015] Preferably, in (2), the adsorption cycle is controlled to be shortened by 0.2 to 1 s in the set time period, such as 0.2 s, 0.5 s, 0.8 s or 1 s.

[0016] Preferably, in (4), the adsorption period is controlled to be extended by 0.2 to 1 s, such as 0.2 s, 0.5 s, 0.8 s or 1 s, during the set time period.

[0017] Since the control system adjusts the adsorption cycle based on the detection value of the first flow meter, in (2), by setting up the second gas storage tank and controlling the opening of the regulating valve based on the detection value of the first flow meter, it can ensure that the gas flow of the first flow meter increases slowly rather than jumps, thereby allowing the adsorption cycle to be shortened smoothly, ensuring the stability and continuity of the product gas. In (4), once Q<Q', the pressure in the second gas storage tank will increase. At this time, the control system controls the opening of the regulating valve based on the detection value of the pressure gauge, which is more timely and ensures the stability of the product gas.

[0018] Preferably, the set time period is 30 to 120 seconds, such as 30 seconds, 60 seconds, 90 seconds or 120 seconds.

[0019] Preferably, the total flow through the second flow meter in the set time period=[(the detection lower limit value of the second flow meter in the set time period+the detection upper limit value of the second flow meter in the set time period) / 2]×the set time period.

[0020] Preferably, in (2) and / or (4), the control system fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer.

[0021] Preferably, the energy-saving pressure swing adsorption gas production equipment further includes a buffer unit disposed between the adsorption unit and the gas storage unit and connected to both.

[0022] Further preferably, the buffer unit includes a buffer tank.

[0023] Preferably, the adsorption unit includes a first adsorber and a second adsorber, and the first valve group includes:

[0024] The first air intake valve and the second air intake valve are respectively arranged on the first adsorber air intake pipeline and the second adsorber air intake pipeline, and are used to connect or disconnect the first adsorber air intake pipeline and the second adsorber air intake pipeline respectively.

[0025] The first exhaust valve and the second exhaust valve are respectively arranged on the first adsorber exhaust pipeline and the second adsorber exhaust pipeline, and are used to connect or disconnect the first adsorber exhaust pipeline and the second adsorber exhaust pipeline respectively.

[0026] The pressure equalizing valve is provided on the pipeline connecting the first adsorber and the second adsorber, and is used to connect or disconnect the pipeline connecting the first adsorber and the second adsorber.

[0027] The first drain valve and the second drain valve are respectively arranged on the first adsorber drain pipeline and the second adsorber drain pipeline, and are used to connect or disconnect the first adsorber drain pipeline and the second adsorber drain pipeline respectively.

[0028] The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the first valve group.

[0029] In some embodiments, the adsorption cycle includes four steps: adsorption, first pressure equalization, desorption, and second pressure equalization. During the adsorption step, the control system controls the first air intake valve, the first exhaust valve, and the second exhaust valve to be open, and the second air intake valve, the second exhaust valve, the pressure equalization valve, and the first exhaust valve to be closed.

[0030] In the first pressure equalization step, the control system controls the first air intake valve, the second air intake valve and the pressure equalization valve to be open, and the first exhaust valve, the second exhaust valve, the first drain valve and the second drain valve to be closed;

[0031] During the desorption process, the control system controls the second air intake valve, the second air exhaust valve and the first exhaust valve to be opened, and the first air intake valve, the first exhaust valve, the second exhaust valve and the pressure equalizing valve to be closed;

[0032] In the second pressure equalization step, the control system controls the first air intake valve, the second air intake valve and the pressure equalization valve to be open, and the first exhaust valve, the second exhaust valve, the first drain valve and the second drain valve to be closed;

[0033] The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the valve in the adsorption and / or desorption process, and the opening and closing time of the valve in the first and second pressure equalization processes remain unchanged.

[0034] Furthermore, the opening and closing time of the valve in the first and second pressure equalization processes is fixed to 1.5 to 2.5 seconds, for example, 1.5 seconds, 1.8 seconds, 2 seconds, 2.3 seconds or 2.5 seconds.

[0035] Preferably, the first valve group further includes a main intake valve provided at the intake ends of the first intake valve and the second intake valve, and the control system controls the main intake valve to open in the adsorption and desorption processes and to close in the first and second pressure equalization processes.

[0036] Preferably, the control method is also based on a third drain valve arranged on the drain pipeline of the energy-saving pressure swing adsorption gas production equipment and a second gas tank inlet valve arranged on the pipeline connecting the first gas tank and the second gas tank. The drain pipeline is connected to the pipeline connecting the first gas tank and the second gas tank. The third drain valve and the second gas tank inlet valve are respectively controlled by the control system and are controlled to be opened or closed by the control system. When the detection value of the gas purity analyzer is lower than the preset value, the control system controls the third drain valve to open and the second gas tank inlet valve to close to drain the gas; when the detection value of the gas purity analyzer is higher than or equal to the preset value, the control system controls the third drain valve to close and the second gas tank inlet valve to open, so that the gas enters the second gas tank.

[0037] Preferably, the gas purity analyzer, the first flow meter and the regulating valve are sequentially arranged along the flow direction of the gas on a pipeline connecting the first gas storage tank and the second gas storage tank.

[0038] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0039] The control method of the present invention can automatically adjust the operating parameters to the most energy-efficient state according to the real-time gas consumption while ensuring that the product gas meets the usage demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A simplified structural diagram of an energy-saving pressure swing adsorption gas production equipment in an embodiment;

[0041] Among them, 1. first adsorber; 2. second adsorber; 3. buffer tank; 4. first gas storage tank; 5. second gas storage tank; 6. gas purity analyzer; 7. first flow meter; 8. second flow meter; 9. pressure gauge;

[0042] A. Air inlet; B. Air outlet; C. Exhaust port;

[0043] P1, main air intake valve; P2, first air intake valve; P3, second air intake valve; P4, first exhaust valve; P5, second exhaust valve; P6, first exhaust valve; P7, second exhaust valve; P8, pressure equalizing valve; P9, second air tank air intake valve; P10, third exhaust valve;

[0044] PV101, regulating valve. DETAILED DESCRIPTION

[0045] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0046] In describing the embodiments of the present invention, it should be understood that the terms "front" and "rear" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These orientations or positional relationships are provided solely for the purpose of facilitating and simplifying the description of the embodiments of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and are therefore not to be construed as limiting the embodiments of the present invention.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0048] To simplify the disclosure of the embodiments of the present invention, the following descriptions are of components and configurations of specific examples. These are, of course, merely illustrative and are not intended to limit the embodiments of the present invention. Furthermore, the embodiments of the present invention may repeat reference numerals and / or reference letters in different examples. This repetition is for simplicity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0049] Example

[0050] See also Figure 1, an energy-saving pressure swing adsorption gas production equipment, including a control system (not shown in the figure) and an adsorption unit, a buffer unit and a gas storage unit that can be connected in sequence from the air inlet direction to the air outlet direction. Among them, the adsorption unit is connected to the air inlet A for introducing raw gas, and the adsorption unit is provided with a first valve group for controlling the air inlet and air outlet of the adsorption unit. The first valve group is controlled by the control system and is controlled to be opened or closed by the control system; the buffer unit includes a buffer tank 3; the gas storage unit is provided with a second valve group, a flow meter group, a gas purity analyzer 6 and a pressure gauge 9, and the gas storage unit includes a first gas tank 4 and a second gas tank 5 connected in series, the second gas tank 5 is located at the rear end of the first gas tank 4 and is connected to the air outlet B, and the second valve group includes a valve group provided at A regulating valve PV101 is located on the pipeline connecting the first gas tank 4 and the second gas tank 5. The regulating valve PV101 is controlled by a control system and its opening is controlled by the control system. A flow meter assembly, a gas purity analyzer 6, and a pressure gauge 9 are each connected to the control system and provide feedback to the control system. The flow meter assembly includes a first flow meter 7 located on the pipeline connecting the first gas tank 4 and the second gas tank 5, and a second flow meter 8 located at the gas outlet of the second gas tank 5. The pressure gauge 9 is located on the second gas tank 5 and is used to detect the pressure within the second gas tank 5. Preferably, the gas purity analyzer 6, the first flow meter 7, and the regulating valve PV101 are sequentially located on the pipeline connecting the first gas tank 4 and the second gas tank 5 along the direction of gas flow.

[0051] A control method for energy-saving pressure swing adsorption gas production equipment includes:

[0052] (1) The control system calculates the total flow Q passing through the second flow meter 8 in the set time period based on the detection value fed back by the second flow meter 8, and compares it with the total flow Q' passing through the second flow meter 8 in the previous set time period. When Q>Q', execute (2); when Q=Q', execute (3); when Q<Q', execute (4);

[0053] (2) The control system controls the opening of the regulating valve PV101 according to the detection value of the first flow meter 7, so that the gas flow through the first flow meter 7 increases slowly and the adsorption cycle of the adsorption unit is shortened until Q and Q' are equal;

[0054] (3) The control system controls the opening of the regulating valve PV101 to remain unchanged, and fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer 6;

[0055] (4) The control system controls the opening of the regulating valve PV101 according to the detection value of the pressure gauge 9, so that the pressure in the second gas storage tank 5 remains stable and the adsorption cycle of the adsorption unit is extended until Q and Q' are equal.

[0056] Because the flow meter's detection value may fluctuate, calculating the total flow rate through the flow meter during a set time period can more accurately reflect the gas output volume. The total flow rate calculation formula is as follows: Total flow rate = [(the flow meter's detection lower limit value during the set time period + the flow meter's detection upper limit value during the set time period) / 2] × set time period. Preferably, the set time period is 30 to 120 seconds. In this embodiment, the set time period is 60 seconds.

[0057] When the gas consumption in the latter stage suddenly increases, in order to meet the gas demand, the adsorption cycle of the energy-saving pressure swing adsorption gas production equipment in the prior art will jump from long to short, resulting in unqualified gas purity in a short period of time. If the adsorption cycle is slowly shortened at this time, thereby slowly increasing the flow rate, the pressure in the latter stage will drop in a short period of time, and the product gas will be insufficient. The inventors have ensured the stability of gas concentration and the continuity of gas supply by gradually shortening the adsorption cycle and ensuring uninterrupted gas supply. Specifically, when the gas consumption increases, that is, Q>Q', since the gas stored in the second gas storage tank 5 can ensure continuous gas supply, the first flowmeter 7 increases slowly instead of jumping. When the control system adjusts the adsorption cycle according to the detection value of the first flowmeter 7, the adsorption cycle can be shortened smoothly. Furthermore, the adsorption cycle is shortened by 0.2 to 1s in the set time period, which is relatively smooth and does not affect the purity of the gas.

[0058] When the gas consumption in the latter stage decreases (i.e., Q < Q'), there will be a certain hysteresis in controlling the opening of the regulating valve PV101 based on the detection value of the first flowmeter 7. In this case, controlling the opening of the regulating valve PV101 based on the detection value of the pressure gauge 9 on the second gas storage tank 5 provides faster and more accurate feedback on the gas consumption. The extension of the adsorption cycle within the set time period is preferably 0.2 to 1 second.

[0059] Furthermore, in the above (2) and (4), the control system also fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer 6 until it is adjusted to a state where the required gas is produced with the least consumption of raw gas, so that the energy-saving pressure swing adsorption gas production equipment can be maintained in the most energy-saving state, achieving the purpose of energy conservation and emission reduction, and having a high degree of automation.

[0060] The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the first valve group. The following is further discussed in conjunction with the adsorption unit and the first valve group. The adsorption unit includes a first adsorber 1 and a second adsorber 2. The first valve group includes:

[0061] The first intake valve P2 and the second intake valve P3 are respectively arranged on the intake pipeline of the first adsorber 1 and the intake pipeline of the second adsorber 2, and are used to connect or disconnect the intake pipeline of the first adsorber 1 and the intake pipeline of the second adsorber 2.

[0062] The first exhaust valve P6 and the second exhaust valve P7 are respectively provided on the exhaust pipeline of the first adsorber 1 and the exhaust pipeline of the second adsorber 2, and are used to connect or disconnect the exhaust pipeline of the first adsorber 1 and the exhaust pipeline of the second adsorber 2, respectively.

[0063] The pressure equalizing valve P8 is provided on the pipeline connecting the first adsorber 1 and the second adsorber 2, and is used to connect or disconnect the pipeline connecting the first adsorber 1 and the second adsorber 2.

[0064] The first drain valve P4 and the second drain valve P5 are respectively arranged on the drain pipeline of the first adsorber 1 and the drain pipeline of the second adsorber 2, and are used to connect or disconnect the drain pipeline of the first adsorber 1 and the drain pipeline of the second adsorber 2, respectively. The drain pipeline of the first adsorber 1 and the drain pipeline of the second adsorber 2 are respectively connected to the drain port C.

[0065] Furthermore, the first intake valve P2, the second intake valve P3, the first exhaust valve P6, the second exhaust valve P7, the pressure equalizing valve P8, the first exhaust valve P4 and the second exhaust valve P5 are pneumatic valves respectively.

[0066] The adsorption cycle includes four processes: adsorption, first pressure equalization, desorption and second pressure equalization. In the adsorption process, the control system controls the first air intake valve P2, the first exhaust valve P6 and the second exhaust valve P5 to open, and the second air intake valve P3, the second exhaust valve P7, the equalizing valve P8 and the first exhaust valve P4 to close; in the first pressure equalization process, the control system controls the first air intake valve P2, the second air intake valve P3 and the equalizing valve P8 to open, and the first exhaust valve P6, the second exhaust valve P7, the first exhaust valve P4 and the second exhaust valve P5 to close; in the desorption process, the control system controls the second air intake valve P3, the second exhaust valve P7 and the first exhaust valve P4 to open, and the first air intake valve P2, the first exhaust valve P6, the second exhaust valve P5 and the equalizing valve P8 to close; in the second pressure equalization process, the control system controls the first air intake valve P2, the second air intake valve P3 and the equalizing valve P8 to open, and the first exhaust valve P6, the second exhaust valve P7, the first exhaust valve P4 and the second exhaust valve P5 to close. The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the valves during the adsorption and / or desorption steps. The opening and closing time of the valves during the first and second pressure equalization steps remains unchanged, preferably fixed to 1.5 to 2.5 seconds, and in this embodiment, 2 seconds.

[0067] Furthermore, the first valve group also includes a master intake valve P1, which is located at the intake ends of the first intake valve P2 and the second intake valve P3. The control system controls the master intake valve P1 to open during the adsorption and desorption processes and close during the first and second pressure equalization processes. The master intake valve P1 is a pneumatic valve.

[0068] The control method is also based on a third drain valve P10 provided on the drain pipe of the energy-saving pressure swing adsorption gas production equipment and a second gas tank inlet valve P9 provided on the pipe connecting the first gas tank 4 and the second gas tank 5. The drain pipe is connected to the pipe connecting the first gas tank 4 and the second gas tank 5, specifically between the gas purity analyzer 6 and the first flow meter 7, and its rear end is connected to the drain port C.

[0069] The third drain valve P10 and the second gas tank inlet valve P9 are each controlled by a control system and are opened or closed by the control system. When the detection value of the gas purity analyzer 6 is lower than a preset value, the control system controls the third drain valve P10 to open and the second gas tank inlet valve P9 to close, allowing gas to be drained. When the detection value of the gas purity analyzer 6 is higher than or equal to the preset value, the control system controls the third drain valve P10 to close and the second gas tank inlet valve P9 to open, allowing gas to enter the second gas tank 5. Furthermore, the third drain valve P10 and the second gas tank inlet valve P9 are both pneumatic valves.

[0070] In order to protect the gas purity analyzer 6, a pressure changing valve is provided at the gas inlet end thereof.

[0071] The above control method is applicable to pressure swing adsorption oxygen production, pressure swing adsorption nitrogen production, etc.

[0072] The above detailed description of the present invention is intended to enable persons familiar with the art to understand the contents of the present invention and implement them. It does not limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A control method for energy-saving pressure swing adsorption gas production equipment, characterized by: Based on the control system, Corresponding to the first valve group of the adsorption unit of the energy-saving pressure swing adsorption gas production equipment, the first valve group is controlled by the control system and is controlled to be opened or closed by the control system, Corresponding to the second valve group, flow meter group, gas purity analyzer and pressure gauge of the gas storage unit of the energy-saving pressure swing adsorption gas production equipment, the gas storage unit includes a first gas tank and a second gas tank, the first gas tank is located between the adsorption unit and the second gas tank and is connected to the two, the second valve group includes a regulating valve arranged on the pipeline connecting the first gas tank and the second gas tank, the regulating valve is controlled by the control system and its opening is controlled by the control system, the flow meter group, gas purity analyzer and pressure gauge are respectively connected to the control system and feed back detection values ​​to the control system, the flow meter group includes a first flow meter arranged on the pipeline connecting the first gas tank and the second gas tank and a second flow meter arranged at the gas outlet end of the second gas tank, the pressure gauge is arranged on the second gas tank, and is used to detect the pressure in the second gas tank, The control method includes: (1) The control system calculates the total flow Q passing through the second flow meter in the set time period based on the detection value fed back by the second flow meter, and compares it with the total flow Q' passing through the second flow meter in the previous set time period. When Q>Q', execute (2); when Q=Q', execute (3); when Q<Q', execute (4); (2) The control system controls the opening of the regulating valve according to the detection value of the first flow meter, so that the gas flow through the first flow meter increases slowly and the adsorption cycle of the adsorption unit is shortened until Q and Q' are equal; (3) The control system controls the opening of the regulating valve to remain unchanged and fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer; (4) The control system controls the opening of the regulating valve according to the detection value of the pressure gauge, so that the pressure in the second gas storage tank remains stable and the adsorption cycle of the adsorption unit is extended until Q and Q' are equal.

2. The control method according to claim 1, wherein: In (2), the adsorption cycle is controlled to be shortened by 0.2 to 1 second in the set time period, and / or, in (4), the adsorption cycle is controlled to be extended by 0.2 to 1 second in the set time period.

3. The control method according to claim 1, wherein: The set time period is 30 to 120 seconds; and / or, The total flow rate through the second flow meter during the set time period=[(the detection lower limit value of the second flow meter during the set time period+the detection upper limit value of the second flow meter during the set time period) / 2]×the set time period.

4. The control method according to claim 1, wherein: In (2) and / or (4), the control system fine-tunes the adsorption cycle of the adsorption unit according to the detection value of the gas purity analyzer.

5. The control method according to claim 1, wherein: The energy-saving pressure swing adsorption gas production equipment further includes a buffer unit disposed between the adsorption unit and the gas storage unit and connected to the both.

6. The control method according to claim 1, wherein: The adsorption unit includes a first adsorber and a second adsorber, and the first valve group includes: The first air intake valve and the second air intake valve are respectively arranged on the first adsorber air intake pipeline and the second adsorber air intake pipeline, and are used to connect or disconnect the first adsorber air intake pipeline and the second adsorber air intake pipeline respectively. The first exhaust valve and the second exhaust valve are respectively arranged on the first adsorber exhaust pipeline and the second adsorber exhaust pipeline, and are used to connect or disconnect the first adsorber exhaust pipeline and the second adsorber exhaust pipeline respectively. The pressure equalizing valve is provided on the pipeline connecting the first adsorber and the second adsorber, and is used to connect or disconnect the pipeline connecting the first adsorber and the second adsorber. The first drain valve and the second drain valve are respectively arranged on the first adsorber drain pipeline and the second adsorber drain pipeline, and are used to connect or disconnect the first adsorber drain pipeline and the second adsorber drain pipeline respectively. The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the first valve group.

7. The control method according to claim 6, characterized in that: The adsorption cycle includes four steps: adsorption, first pressure equalization, desorption, and second pressure equalization. During the adsorption step, the control system controls the first air intake valve, the first exhaust valve, and the second exhaust valve to be open, and the second air intake valve, the second exhaust valve, the pressure equalization valve, and the first exhaust valve to be closed. In the first pressure equalization step, the control system controls the first air intake valve, the second air intake valve and the pressure equalization valve to be open, and the first exhaust valve, the second exhaust valve, the first drain valve and the second drain valve to be closed; During the desorption process, the control system controls the second air intake valve, the second air exhaust valve and the first exhaust valve to be opened, and the first air intake valve, the first exhaust valve, the second exhaust valve and the pressure equalizing valve to be closed; In the second pressure equalization step, the control system controls the first air intake valve, the second air intake valve and the pressure equalization valve to be open, and the first exhaust valve, the second exhaust valve, the first drain valve and the second drain valve to be closed; The control system shortens or lengthens the adsorption cycle by controlling the opening and closing time of the valve in the adsorption and / or desorption process, and the opening and closing time of the valve in the first and second pressure equalization processes remain unchanged.

8. The control method according to claim 7, wherein: The opening and closing time of the valve in the first and second pressure equalization steps is fixed to 1.5 to 2.5 seconds; and / or, The first valve group further includes a main intake valve provided at the intake ends of the first intake valve and the second intake valve. The control system controls the main intake valve to be opened during the adsorption and desorption processes and closed during the first pressure equalization process and the second pressure equalization process.

9. The control method according to claim 1, wherein: The control method is also based on a third drain valve arranged on the drain pipeline of the energy-saving pressure swing adsorption gas production equipment and a second gas tank inlet valve arranged on the pipeline connecting the first gas tank and the second gas tank. The drain pipeline is connected to the pipeline connecting the first gas tank and the second gas tank. The third drain valve and the second gas tank inlet valve are respectively controlled by the control system and are controlled to be opened or closed by the control system. When the detection value of the gas purity analyzer is lower than the preset value, the control system controls the third drain valve to open and the second gas tank inlet valve to close to drain the gas; when the detection value of the gas purity analyzer is higher than or equal to the preset value, the control system controls the third drain valve to close and the second gas tank inlet valve to open to allow the gas to enter the second gas tank.

10. The control method according to claim 1, characterized in that: The gas purity analyzer, the first flow meter and the regulating valve are sequentially arranged along the flow direction of the gas on a pipeline connecting the first gas storage tank and the second gas storage tank.

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