Intelligent purification method and device for ventilation air methane

Abstract

The invention discloses an intelligent purification method and device for ventilation air methane, and particularly relates to the technical field of methane purification. Key parameters and key output indexes of an adsorption tower in the adsorption process are obtained, and the key parameters of the adsorption tower are adjusted according to the key parameters and adjustment key parameters; after the adsorption tower is adjusted according to the key parameters, the air inlet flow and temperature of the adsorption tower are adjusted according to a preset pressure curve; the saturation state of the adsorbent is judged according to the concentration of methane in the outlet gas of the adsorption tower, the change of the internal pressure and temperature of the adsorption tower and the adsorption time, and the working condition of the adsorption tower is switched into the desorption working condition according to the saturation state of the adsorbent, so that the working condition can be adjusted and controlled in real time according to the actual ventilation air methane purification state; the concentration of methane adsorbed by the adsorption tower is high, the energy consumption is low, and the desorption time is short.

Description

Technical Field

[0001] The present invention relates to the technical field of methane purification, and in particular to an intelligent purification method and device for exhaust gas. Background Art

[0002] Air-deficient methane refers to low-concentration methane (less than 0.75%) produced during coal mining. Its direct emission will produce a large amount of greenhouse gas effects. Due to the extremely low concentration of methane in air-deficient methane, it is difficult to utilize. Traditionally, this part of methane is difficult to recycle and utilize, which has become a global environmental problem. However, with the advancement of technology, the resource utilization of air-deficient methane has gradually become possible.

[0003] Air separation equipment is an air separation device, usually used to purify oxygen, nitrogen and other gases from the air. In the process of utilizing exhaust gas, air separation equipment can also be used to treat and purify useful gas components such as methane in exhaust gas. This technical means can achieve the effective recycling of exhaust gas and avoid the impact of its direct emission on the environment.

[0004] However, in the actual exhaust gas gas purification process, the control conditions cannot be adjusted in real time according to the actual exhaust gas gas purification status, which may result in a low adsorbed methane concentration, high energy consumption, and a long desorption time. Summary of the invention

[0005] The purpose of the present invention is to solve the problem and to propose an intelligent purification method and device for lack of wind gas.

[0006] In the first aspect of the implementation of the present invention, a smart purification method for exhaust gas is first proposed, the method comprising:

[0007] Obtaining key parameters and key output indicators of the adsorption tower during the adsorption process, and adjusting the key parameters of the adsorption tower according to the key parameters and adjusting the key parameters; the key parameters include inlet air flow, pressure in the tower, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption;

[0008] After the adsorption tower is adjusted according to the key parameters, the air inlet flow rate and temperature of the adsorption tower are adjusted according to the preset pressure curve;

[0009] The saturation state of the adsorbent is determined based on the methane concentration in the adsorption tower outlet gas, the changes in pressure and temperature inside the adsorption tower, and the adsorption time, and the operating condition of the adsorption tower is switched to the desorption condition based on the saturation state of the adsorbent.

[0010] Optionally, adjusting the key parameters of the adsorption tower according to the key parameters and adjusting the key parameters includes:

[0011] Obtaining the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculating the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration;

[0012] Obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency;

[0013] Get the average energy consumption within a preset time period as the actual energy consumption;

[0014] Compare the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters;

[0015] When any of the key output indicators, including the actual outlet methane concentration, adsorption efficiency and actual energy consumption, is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, and then stop adjusting the key parameter.

[0016] Optionally, adjusting the air inlet flow rate and temperature of the adsorption tower according to a preset pressure curve includes:

[0017] The pressure inside the adsorption tower is adjusted according to the preset pressure curve, and the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower are monitored in real time;

[0018] If the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the inlet gas flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0019] If the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increasing the inlet flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0020] Obtaining the adsorption tower temperature, calculating the rising rate of the adsorption tower temperature, and comparing the rising rate of the adsorption tower temperature with a preset temperature rising rate range;

[0021] If the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range;

[0022] If the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

[0023] Optionally, judging the saturation state of the adsorbent according to the concentration of methane in the gas at the outlet of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower, and the adsorption time includes:

[0024]

[0025] Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients;

[0026] The saturation state of the adsorbent is determined based on the comprehensive saturation of the adsorbent.

[0027] Optionally, judging the saturation state of the adsorbent according to the comprehensive saturation of the adsorbent includes:

[0028] The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0029] If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0030] In a second aspect of the present invention, a smart purification device for exhaust gas is provided, the device comprising:

[0031] The first adjustment module: obtains the key parameters and key output indicators of the adsorption tower during the adsorption process, and adjusts the key parameters of the adsorption tower according to the key parameters and the adjusted key parameters; the key parameters include inlet air flow, tower pressure, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption;

[0032] The second regulating module: after the adsorption tower is regulated according to the key parameters, the air inlet flow and temperature of the adsorption tower are adjusted according to the preset pressure curve;

[0033] Working condition switching module: the saturation state of the adsorbent is judged according to the methane concentration in the gas at the outlet of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower and the adsorption time, and the working condition of the adsorption tower is switched to the desorption condition according to the saturation state of the adsorbent.

[0034] Optionally, the first adjustment module includes:

[0035] Outlet methane concentration module: obtains the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculates the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration;

[0036] Adsorption efficiency module: obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency;

[0037] Actual energy consumption module: obtains the average energy consumption within a preset time period as the actual energy consumption;

[0038] The first comparison and adjustment module: compares the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters;

[0039] Second comparison and adjustment module: When any key output indicator among the actual outlet methane concentration, adsorption efficiency and actual energy consumption is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, then stop adjusting the key parameter.

[0040] Optionally, the second adjustment module includes:

[0041] Pressure regulation module: adjusts the pressure inside the adsorption tower according to the preset pressure curve, and monitors the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower in real time;

[0042] A first intake air flow regulating module: if the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0043] The second intake air flow regulating module: if the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increase the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0044] Temperature adjustment module: obtains the temperature of the adsorption tower, calculates the rising rate of the temperature of the adsorption tower, and compares the rising rate of the temperature of the adsorption tower with the preset temperature rising rate range;

[0045] The first temperature adjustment module: if the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range;

[0046] The second temperature regulating module: if the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

[0047] Optionally, the operating mode switching module includes a saturation calculation module and a saturation state judgment module:

[0048] The saturation calculation module is used to calculate the comprehensive saturation of the adsorbent, and the calculation formula is:

[0049]

[0050] Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients;

[0051] Saturation state judgment module: judge the saturation state of the adsorbent according to the comprehensive saturation of the adsorbent.

[0052] Optionally, the saturation state judgment module includes:

[0053] The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0054] If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0055] Beneficial effects of the present invention:

[0056] The present invention proposes an intelligent purification method and device for exhaust gas, which obtains key parameters and key output indicators of an adsorption tower in the adsorption process, and adjusts the key parameters of the adsorption tower according to the key parameters and the adjusted key parameters; after the adsorption tower is adjusted according to the key parameters, the air intake flow rate and temperature of the adsorption tower are adjusted according to a preset pressure curve; and the saturation state of the adsorbent is judged according to the concentration of methane in the outlet gas of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower, and the adsorption time, and the operating condition of the adsorption tower is switched to a desorption condition according to the saturation state of the adsorbent. In this way, the control operating condition can be adjusted in real time according to the actual exhaust gas purification state, so that the methane concentration adsorbed by the adsorption tower is higher, the energy consumption is lower, and the desorption time is shorter. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The present invention will be further described below in conjunction with the accompanying drawings.

[0058] Figure 1 A flowchart of an intelligent purification method for lack of air gas;

[0059] Figure 2 The present invention is a framework diagram of an intelligent purification device for lack of wind gas. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0062] The embodiment of the present invention provides a smart purification method for exhaust gas. Figure 1 , Figure 1 A flow chart of a smart purification method for exhaust gas provided in an embodiment of the present invention. The method comprises the following steps:

[0063] Obtain the key parameters and key output indicators of the adsorption tower during the adsorption process, and adjust the key parameters of the adsorption tower according to the key parameters and the key parameters; the key parameters include inlet air flow, pressure in the tower, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption;

[0064] After the adsorption tower is adjusted according to the key parameters, the air inlet flow rate and temperature of the adsorption tower are adjusted according to the preset pressure curve;

[0065] The saturation state of the adsorbent is determined based on the methane concentration in the adsorption tower outlet gas, the changes in pressure and temperature inside the adsorption tower, and the adsorption time, and the operating condition of the adsorption tower is switched to the desorption condition based on the saturation state of the adsorbent.

[0066] Based on an intelligent purification method for exhaust gas provided in an embodiment of the present invention, through the above-mentioned method, the control working conditions can be adjusted in real time according to the actual exhaust gas purification state, so that the methane concentration adsorbed by the adsorption tower is higher, the energy consumption is lower, and the desorption time is shorter.

[0067] In one embodiment, adjusting the key parameters of the adsorption tower according to the key parameters and adjusting the key parameters includes:

[0068] Obtaining the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculating the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration;

[0069] Obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency;

[0070] Get the average energy consumption within a preset time period as the actual energy consumption;

[0071] Compare the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters;

[0072] When any of the key output indicators, including the actual outlet methane concentration, adsorption efficiency and actual energy consumption, is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, and then stop adjusting the key parameter.

[0073] It should be noted that the preset time period is set by professionals according to actual conditions, and no specific limitation or elaboration is made; in addition, the preset outlet methane concentration range, the preset adsorption efficiency range, and the preset energy consumption range are also set by professionals according to actual conditions, and no specific limitation or elaboration is made;

[0074] It should be noted that the outlet methane concentration can be monitored in real time by a gas analyzer installed at the outlet of the adsorption tower; the adsorption efficiency is obtained by calculating the difference between the inlet methane concentration and the outlet methane concentration, and combining it with the inlet concentration; the energy consumption is monitored by energy metering equipment during the adsorption and desorption process of the adsorption tower, such as the use of electrical energy or thermal energy. The specific acquisition can be determined according to the actual situation and is not limited or elaborated.

[0075] In one implementation, through the above method, by real-time monitoring and dynamic adjustment of the inlet flow rate, tower pressure, temperature, adsorption time and desorption time, the adsorption efficiency can be optimized to ensure effective purification of methane, while reducing energy consumption and extending the service life of the adsorbent. This intelligent control method can enable the system to always maintain efficient and stable operation under different working conditions, improving overall economic and environmental benefits.

[0076] In one embodiment, adjusting the inlet air flow rate and temperature of the adsorption tower according to a preset pressure curve includes:

[0077] The pressure inside the adsorption tower is adjusted according to the preset pressure curve, and the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower are monitored in real time;

[0078] If the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the inlet flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0079] If the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increasing the inlet flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0080] Obtaining the adsorption tower temperature, calculating the rising rate of the adsorption tower temperature, and comparing the rising rate of the adsorption tower temperature with a preset temperature rising rate range;

[0081] If the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range;

[0082] If the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

[0083] It should be noted that the preset pressure curve is pre-set by professional staff according to the characteristics of the adsorbent, gas concentration and system design conditions. Usually, the pressure in the tower will be gradually increased at the beginning of adsorption until the optimal working pressure of the adsorbent is reached. During the adsorption process, the system will gradually increase the pressure in the tower according to the preset time or the inlet flow controller. This can be done by adjusting the valve or compressor to control the inlet pressure to avoid sudden high pressure from causing shock to the adsorbent and equipment. A pressure sensor is installed to monitor the pressure in the tower in real time to ensure that the pressure curve can rise smoothly. If the pressure rises too fast or too slow, the system will automatically adjust the intake rate or compressor output to ensure that the pressure rises steadily.

[0084] It should be noted that the preset minimum outlet methane concentration and the preset temperature rise rate range are set by professionals according to actual conditions, and are not specifically limited or elaborated;

[0085] It should be noted that if the methane concentration in the outlet gas is greater than the preset minimum outlet methane concentration, it means that the adsorption is insufficient, and the intake flow rate can be slightly reduced to increase the contact time between the gas and the adsorbent to improve the adsorption efficiency; if the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, it means that the degree of adsorption unsaturation is slightly high, and the intake flow rate can be appropriately increased to improve the processing efficiency and adsorption rate. If the methane concentration in the outlet gas is greater than or equal to the preset minimum outlet methane concentration, it means that the adsorption efficiency is the highest at this time and no adjustment is required.

[0086] It should be noted that by installing a temperature sensor, the temperature changes in the adsorption tower are monitored. During the adsorption process, temperature fluctuations may indicate that the adsorption performance of the adsorbent has changed. If the rate of increase of the temperature of the adsorption tower is greater than the maximum value of the preset temperature rise rate range, it means that too much heat is accumulated in the adsorption process. The temperature can be lowered by the cooling system to avoid a decrease in adsorption efficiency. If the rate of increase of the temperature of the adsorption tower is less than the minimum value of the preset temperature rise rate range, the heating system can be used to increase the temperature appropriately to keep the adsorption process within the optimal temperature range (that is, the temperature range corresponding to the preset temperature rise rate range).

[0087] In one implementation method, by adjusting the air intake flow rate and temperature of the adsorption tower, the methane purification process can be optimized while ensuring the adsorption efficiency. Reducing the air intake flow rate can extend the contact time between the gas and the adsorbent and improve the methane adsorption effect, while increasing the flow rate increases the processing rate. When the temperature rises too quickly, timely cooling is performed to avoid a decrease in the adsorption efficiency, and when the temperature rises too slowly, heating is used to maintain the optimal adsorption temperature range. This dynamic adjustment can effectively balance the adsorption efficiency, processing rate and energy consumption, ensure stable and efficient operation of the system, and reduce energy waste.

[0088] In one embodiment, judging the saturation state of the adsorbent according to the concentration of methane in the gas at the outlet of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower, and the adsorption time includes:

[0089]

[0090] Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients;

[0091] The saturation state of the adsorbent is determined based on the comprehensive saturation of the adsorbent.

[0092] It should be noted that the comprehensive saturation range of the adsorbent is between 0 and 1, and when it is close to 1, it indicates that the adsorbent is close to saturation; the outlet methane concentration, inlet air flow, inlet methane concentration, tower pressure, temperature, and duration of the adsorption process are all obtained through installed sensors and instruments; the preset weight coefficient and maximum adsorption capacity parameters are set by professionals according to actual conditions, and are not limited or elaborated on in detail;

[0093] In one implementation, through the above method, multiple key parameters, such as changes in methane concentration, adsorption time, pressure and temperature, can be comprehensively considered to provide a more comprehensive judgment on the saturation state of the adsorbent; by balancing the importance of each parameter through a weight coefficient and combining the ratio of the actual adsorption amount to the maximum adsorption capacity, this method can more accurately reflect the current working state of the adsorbent, avoid entering the desorption stage too early or too late, thereby optimizing the adsorption efficiency, reducing energy consumption, and improving the overall operating stability of the system.

[0094] In one embodiment, judging the saturation state of the adsorbent according to the comprehensive saturation of the adsorbent includes:

[0095] The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0096] If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0097] It should be noted that the maximum threshold of the comprehensive saturation of the preset adsorbent is set by professionals according to the actual situation, and no specific limitation or elaboration is made;

[0098] In one implementation method, the operating condition of the adsorption tower can be switched to the desorption condition according to the actual situation, which can quickly reduce the pressure in the tower and promote the rapid desorption and release of methane on the adsorbent; at the same time, the desorption pressure is also precisely controlled to ensure that the concentration of desorbed methane reaches the highest level while reducing energy consumption and desorption time; the control strategy is adjusted in real time according to the adsorption performance of the adsorbent and the current operating conditions to ensure precise control of the entire adsorption-desorption process.

[0099] Based on the same inventive concept, the present invention also provides an intelligent purification device for exhaust gas. Figure 2 , Figure 2 A framework diagram of an intelligent purification device for exhaust gas provided in an embodiment of the present invention, the device comprising:

[0100] The first adjustment module: obtains the key parameters and key output indicators of the adsorption tower during the adsorption process, and adjusts the key parameters of the adsorption tower according to the key parameters and adjusts the key parameters; the key parameters include inlet flow rate, tower pressure, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption;

[0101] The second regulating module: after the adsorption tower is regulated according to the key parameters, the air inlet flow and temperature of the adsorption tower are adjusted according to the preset pressure curve;

[0102] Working condition switching module: the saturation state of the adsorbent is judged according to the methane concentration in the gas at the outlet of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower and the adsorption time, and the working condition of the adsorption tower is switched to the desorption condition according to the saturation state of the adsorbent.

[0103] Based on an intelligent purification device for exhaust gas provided in an embodiment of the present invention, the control working conditions can be adjusted in real time according to the actual exhaust gas purification state through the above method, so that the methane concentration adsorbed by the adsorption tower is higher, the energy consumption is lower, and the desorption time is shorter.

[0104] In one embodiment, the first adjustment module includes:

[0105] Outlet methane concentration module: obtains the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculates the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration;

[0106] Adsorption efficiency module: obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency;

[0107] Actual energy consumption module: obtains the average energy consumption within a preset time period as the actual energy consumption;

[0108] The first comparison and adjustment module: compares the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters;

[0109] Second comparison and adjustment module: When any key output indicator among the actual outlet methane concentration, adsorption efficiency and actual energy consumption is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, then stop adjusting the key parameter.

[0110] In one embodiment, the second adjustment module includes:

[0111] Pressure regulation module: adjusts the pressure inside the adsorption tower according to the preset pressure curve, and monitors the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower in real time;

[0112] A first intake air flow regulating module: if the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0113] The second intake air flow regulating module: if the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increase the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration;

[0114] Temperature adjustment module: obtains the temperature of the adsorption tower, calculates the rising rate of the temperature of the adsorption tower, and compares the rising rate of the temperature of the adsorption tower with the preset temperature rising rate range;

[0115] The first temperature adjustment module: if the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range;

[0116] The second temperature regulating module: if the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

[0117] In one embodiment, the operating mode switching module includes a saturation calculation module and a saturation state judgment module:

[0118] The saturation calculation module is used to calculate the comprehensive saturation of the adsorbent. The calculation formula is:

[0119]

[0120] Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients;

[0121] Saturation state judgment module: judge the saturation state of the adsorbent according to the comprehensive saturation of the adsorbent.

[0122] In one embodiment, the saturation state determination module includes:

[0123] The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0124] If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

[0125] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A smart purification method for exhaust gas, characterized in that: The following steps are involved: Obtaining key parameters and key output indicators of the adsorption tower during the adsorption process, and adjusting the key parameters of the adsorption tower according to the key parameters and adjusting the key parameters; the key parameters include inlet air flow, pressure in the tower, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption; After the adsorption tower is adjusted according to the key parameters, the air inlet flow rate and temperature of the adsorption tower are adjusted according to the preset pressure curve; The saturation state of the adsorbent is determined based on the methane concentration in the adsorption tower outlet gas, the changes in pressure and temperature inside the adsorption tower, and the adsorption time, and the operating condition of the adsorption tower is switched to the desorption condition based on the saturation state of the adsorbent.

2. The intelligent purification method for exhaust gas according to claim 1, characterized in that: Adjusting the key parameters of the adsorption tower according to the key parameters and adjusting the key parameters includes: Obtaining the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculating the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration; Obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency; Get the average energy consumption within a preset time period as the actual energy consumption; Compare the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters; When any of the key output indicators, including the actual outlet methane concentration, adsorption efficiency and actual energy consumption, is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, and then stop adjusting the key parameter.

3. The intelligent purification method for exhaust gas according to claim 1, characterized in that: According to the preset pressure curve and adjusting the inlet flow rate and temperature of the adsorption tower include: The pressure inside the adsorption tower is adjusted according to the preset pressure curve, and the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower are monitored in real time; If the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the inlet gas flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration; If the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increasing the inlet flow rate until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration; Obtaining the adsorption tower temperature, calculating the rising rate of the adsorption tower temperature, and comparing the rising rate of the adsorption tower temperature with a preset temperature rising rate range; If the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range; If the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

4. The intelligent purification method for exhaust gas according to claim 1, characterized in that: The saturation state of the adsorbent can be determined based on the methane concentration in the gas at the adsorption tower outlet, the changes in pressure and temperature inside the adsorption tower, and the adsorption time. Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients; The saturation state of the adsorbent is determined based on the comprehensive saturation of the adsorbent.

5. The intelligent purification method for exhaust gas according to claim 4, characterized in that: The saturation state of the adsorbent can be determined based on the comprehensive saturation of the adsorbent: The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition. If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

6. An intelligent purification device for exhaust gas, characterized in that: The device comprises: The first adjustment module: obtains the key parameters and key output indicators of the adsorption tower during the adsorption process, and adjusts the key parameters of the adsorption tower according to the key parameters and the adjusted key parameters; the key parameters include inlet air flow, tower pressure, temperature, adsorption time and desorption time, and the key output indicators include outlet methane concentration, adsorption efficiency, and energy consumption; The second regulating module: after the adsorption tower is regulated according to the key parameters, the air inlet flow and temperature of the adsorption tower are adjusted according to the preset pressure curve; Working condition switching module: the saturation state of the adsorbent is judged according to the methane concentration in the gas at the outlet of the adsorption tower, the changes in the pressure and temperature inside the adsorption tower and the adsorption time, and the working condition of the adsorption tower is switched to the desorption condition according to the saturation state of the adsorbent.

7. The intelligent purification device for exhaust gas according to claim 6, characterized in that: The first adjustment module includes: Outlet methane concentration module: obtains the outlet methane concentration of the adsorption tower at different times within a preset time period, and calculates the average value of the outlet methane concentration within the preset time period as the actual outlet methane concentration; Adsorption efficiency module: obtain the average inlet methane concentration of the adsorption tower within a preset time period, calculate the absolute difference between the average inlet methane concentration and the actual outlet methane concentration, and divide the absolute difference by the average inlet methane concentration to obtain the adsorption efficiency; Actual energy consumption module: obtains the average energy consumption within a preset time period as the actual energy consumption; The first comparison and adjustment module: compares the actual outlet methane concentration, adsorption efficiency and actual energy consumption with the preset outlet methane concentration range, the preset adsorption efficiency range and the preset energy consumption range respectively. When all three are within the corresponding preset ranges, there is no need to adjust the values ​​of the key parameters; Second comparison and adjustment module: When any key output indicator among the actual outlet methane concentration, adsorption efficiency and actual energy consumption is not within the preset range, it is necessary to adjust the value of the key parameter until the actual outlet methane concentration, adsorption efficiency and actual energy consumption are all within the preset range, then stop adjusting the key parameter.

8. The intelligent purification device for exhaust gas according to claim 6, characterized in that: The second adjustment module includes: Pressure regulation module: adjusts the pressure inside the adsorption tower according to the preset pressure curve, and monitors the methane concentration at the outlet of the adsorption tower and the temperature of the adsorption tower in real time; A first intake air flow regulating module: if the methane concentration in the outlet gas is greater than a preset minimum outlet methane concentration, reducing the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration; The second intake air flow regulating module: if the methane concentration in the outlet gas is less than the preset minimum outlet methane concentration, increase the intake air flow until the methane concentration in the outlet gas is equal to the preset minimum outlet methane concentration; Temperature adjustment module: obtains the temperature of the adsorption tower, calculates the rising rate of the temperature of the adsorption tower, and compares the rising rate of the temperature of the adsorption tower with the preset temperature rising rate range; The first temperature adjustment module: if the rising rate of the adsorption tower temperature is greater than the maximum value of the preset temperature rising rate range, the temperature of the adsorption tower is adjusted down until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range; The second temperature regulating module: if the rising rate of the adsorption tower temperature is less than the minimum value of the preset temperature rising rate range, the temperature of the adsorption tower is increased until the rising rate of the adsorption tower temperature is within the preset temperature rising rate range.

9. The intelligent purification device for exhaust gas according to claim 6, characterized in that: The working mode switching module includes a saturation calculation module and a saturation state judgment module: The saturation calculation module is used to calculate the comprehensive saturation of the adsorbent, and the calculation formula is: Where ED is the comprehensive saturation of the adsorbent; N is the number of divisions of the duration of the adsorption process in the adsorption tower; Co(t i ) indicates t i The methane concentration at the outlet of the adsorption tower at the time; Cin represents the average inlet methane concentration; qa(t i ) indicates t i The actual amount of methane adsorbed at the time, q max It indicates the maximum adsorption capacity of the adsorbent; Indicates time t i The rate of change of pressure inside the adsorption tower, expressed as the derivative of pressure with respect to time; Indicates time t i The rate of temperature change inside the adsorption tower, expressed as the derivative of temperature with respect to time; and Indicates the maximum pressure change rate and temperature change rate during the adsorption process; ω1, ω2, ω3, ω4 are preset weight coefficients; Saturation state judgment module: judge the saturation state of the adsorbent according to the comprehensive saturation of the adsorbent.

10. The intelligent purification device for exhaust gas according to claim 9, characterized in that: The saturation state judgment module comprises: The comprehensive saturation of the adsorbent is compared with the preset maximum threshold of the comprehensive saturation of the adsorbent. If the comprehensive saturation of the adsorbent is not less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged to be saturated, and the operating condition of the adsorption tower is switched to the desorption condition. If the comprehensive saturation of the adsorbent is less than the preset maximum threshold of the comprehensive saturation of the adsorbent, the saturation state of the adsorbent is judged as unsaturated, and the adsorption tower continues to purify the exhaust gas until the saturation state of the adsorbent is saturated, and the operating condition of the adsorption tower is switched to the desorption condition.

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