Organic waste gas desorption condensation treatment method and system

Abstract

The invention relates to the technical field of flow control, in particular to an organic waste gas desorption condensation treatment method and system.The method comprises the steps that internal temperature sequences and external temperature sequences corresponding to condensation equipment in a condensation state and condensation equipment in a condensation regeneration state at all moments are obtained respectively, obtaining a condensation completion moment after each condensation completion and a regeneration completion moment after each condensation regeneration completion; determining relative condensation efficiency, relative internal and external temperature difference and temperature gradient characteristics at each moment; determining the condensation progress at any historical condensation moment and the regeneration progress at any historical regeneration moment; determining a real-time regeneration progress, a real-time condensation progress and a condensation progress error at the current moment; and in combination with a PID algorithm, the flow of the heating medium is controlled. The flow of the heating medium is regulated and controlled in real time, so that the condensation process and the condensation capacity regeneration process are synchronously carried out, the overall energy consumption of the condensation equipment is reduced, and aging of the equipment is delayed.

Description

Technical Field

[0001] The present application relates to the field of flow control technology, and in particular to a method and system for desorption and condensation treatment of organic waste gas. Background Art

[0002] Since the demand for condensation of organic waste gas is continuous, some organic matter in the organic waste gas is easy to condense on the condensation pipe, thereby affecting the condensation capacity of the condensation equipment. Therefore, the condensation device needs to periodically liquefy, separate and collect the organic matter condensed on the pipe to ensure that the condensation equipment can work normally. When condensing organic waste gas, two sets of condensation equipment are usually arranged for alternating use. When one set of condensation equipment is condensing organic waste gas, the other set of condensation equipment is liquefying the attached organic matter, thereby completing the regeneration of the condensation capacity of the condensation equipment.

[0003] For the regeneration of the condensing capacity of the condensing equipment, the traditional method usually introduces a heat medium into the condensing pipe to complete the liquefaction of the attached organic matter, so that the condensing equipment can restore its condensing capacity as soon as possible. Among them, the traditional method uses a heat medium with a fixed flow rate, a fixed time length, and a fixed temperature to liquefy the attached organic matter. However, an excessive heat medium flow rate will cause the condensing equipment to undergo a huge deformation in a short period of time, which can easily accelerate the aging of the condensing equipment. At the same time, it will also cause the condensing equipment to overheat, resulting in increased energy consumption. Therefore, in the process of desorption and condensation of organic waste gas, there are problems of increased energy consumption and equipment aging due to improper control of the heat medium flow signal. Summary of the invention

[0004] In order to solve the above technical problems, a method and system for desorption and condensation treatment of organic waste gas are provided to solve the existing problems.

[0005] The solution to the technical problem of the present application is to provide a method and system for desorption and condensation of organic waste gas, including the following steps:

[0006] In a first aspect, an embodiment of the present application provides a method for desorption and condensation of organic waste gas, the method comprising the following steps:

[0007] Obtain the internal temperature sequence and external temperature sequence corresponding to the condensing device in the condensing state at each moment, and the internal temperature sequence and external temperature sequence corresponding to the condensing device in the condensing regeneration state at each moment; obtain the condensation completion time after each condensation is completed, and the regeneration completion time after each condensation regeneration is completed;

[0008] Based on the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing state at each moment, the relative condensing efficiency at each moment is determined; the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing regeneration state at each moment is analyzed to obtain the relative internal and external temperature difference at each moment; based on the rate of change of the internal and external temperature difference between each moment and the adjacent moment of the condensing device in the condensing regeneration state and the degree of deviation of its distribution, the temperature gradient characteristics at each moment are calculated;

[0009] All moments in the multiple condensation processes and all moments in the multiple condensation regeneration processes of the condensing device before the current moment are recorded as each historical condensation moment and each historical regeneration moment respectively; based on any historical condensation moment and the condensation completion moment, any historical regeneration moment and the regeneration completion moment, the condensation progress of any historical condensation moment and the regeneration progress of any historical regeneration moment are determined respectively;

[0010] Determine the real-time regeneration progress at the current moment according to the relative internal and external temperature difference and the difference in temperature gradient characteristics between the current moment and all historical regeneration moments, combined with the regeneration progress;

[0011] Determine the real-time condensation progress at the current moment according to the difference in relative condensation efficiency between the current moment and all historical condensation moments and the condensation progress;

[0012] Based on the real-time regeneration progress and the real-time condensation progress, the condensation progress error at the current moment is determined, and combined with the PID algorithm, the heat medium flow in the condensing device that is in the condensation regeneration state at the current moment is controlled.

[0013] Preferably, determining the relative condensation efficiency at each moment includes:

[0014] The difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing state at each moment is used to form a condensing temperature difference sequence; the average value of all elements in the condensing temperature difference sequence is recorded as the heat exchange temperature difference;

[0015] The ratio of the heat exchange temperature difference at each moment to the preset temperature difference threshold is used as the relative condensation efficiency at each moment.

[0016] Preferably, obtaining the relative internal and external temperature difference at each moment includes:

[0017] Based on the control input in the condensing system, the heat medium temperature and the refrigerant temperature of the condensing system input are obtained; and the difference between the heat medium temperature and the refrigerant temperature is recorded as the maximum temperature difference;

[0018] The difference between the internal temperature sequence and the external temperature sequence in the condensing device in the condensing regeneration state at each moment constitutes a regeneration temperature difference sequence; the average value of all elements in the regeneration temperature difference sequence is recorded as the condensation regeneration temperature difference;

[0019] The ratio of the condensation regeneration temperature difference at each moment to the maximum temperature difference is taken as the relative internal and external temperature difference at each moment.

[0020] Preferably, the calculation method of the temperature gradient characteristics at each moment is:

[0021] The difference between the regeneration temperature difference sequence at each moment and the previous moment is used to form a temperature difference speed sequence;

[0022] The skewness of the temperature difference velocity sequence is calculated as the temperature gradient characteristic at each moment, wherein if the skewness is less than a preset first value, the temperature gradient characteristic is assigned a preset first value, and if the skewness is greater than a preset second value, the temperature gradient characteristic is assigned a preset second value, wherein the preset first value is less than the preset second value.

[0023] Preferably, the determining of the condensation progress at any historical condensation moment and the regeneration progress at any historical regeneration moment includes:

[0024] The time interval between any historical condensation moment and the condensation completion moment in each condensation process is used as the condensation progress of any historical condensation moment;

[0025] The time interval between any historical regeneration moment and the regeneration completion moment in each condensation regeneration process is used as the regeneration progress of any historical regeneration moment.

[0026] Preferably, determining the real-time regeneration progress at the current moment includes:

[0027] The relative internal and external temperature difference of the condensing device in the condensing regeneration state at the current moment is used as the temperature feature weight at the current moment;

[0028] The calculation method of the temperature characteristic similarity between the current moment and any of the historical regeneration moments is: Among them, DT t→g is the temperature characteristic similarity between the current time t and the g-th historical regeneration time, γ t is the relative internal and external temperature difference of the condensing equipment in the condensing regeneration state at the current time t, γ g is the relative internal and external temperature difference at the g-th historical regeneration moment, δ t is the temperature gradient characteristic of the condensing equipment in the condensing regeneration state at the current time t, δ gis the temperature gradient characteristic at the g-th historical regeneration moment, ε t is the temperature characteristic weight of the condensing device in the condensing regeneration state at the current time t, and τ is a preset value greater than 0;

[0029] The temperature characteristic similarity between the current moment and all historical regeneration moments is normalized, and the regeneration progress of all historical regeneration moments and the normalized result are weighted summed as the real-time regeneration progress of the current moment.

[0030] Preferably, the real-time condensation progress Fr at the current time t t The calculation method is: Among them, F s is the condensation progress at the sth historical condensation moment, β s is the relative condensation efficiency at the sth historical condensation moment, β t is the relative condensation efficiency at the current time t, S t is the number of all historical condensation moments corresponding to the current moment t, and ∈ is a preset value greater than 0.

[0031] Preferably, the condensation progress error J at the current time t is t The calculation method of J is: t =Dr t -(Fr t +M), where Dr t is the real-time regeneration progress at the current time t, Fr t is the real-time condensation progress at the current time t, and M is the preset redundant time.

[0032] Preferably, the controlling of the heat medium flow rate in the condensing device currently in the condensing regeneration state includes:

[0033] The condensation progress error is used as the input of the PID algorithm, and the output is a flow control signal of the heat medium flow. The condensation system adjusts and controls the heat medium flow in the condensing device that is currently in the condensation regeneration state according to the flow control signal.

[0034] In the second aspect, an embodiment of the present application also provides an organic waste gas desorption and condensation treatment system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above-mentioned organic waste gas desorption and condensation treatment methods when executing the computer program.

[0035] This application has at least the following beneficial effects:

[0036] The present application determines the relative condensation efficiency at each moment based on the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing state at each moment, and its beneficial effect is that the condensation capacity of the condensing device in the condensing state at this moment is taken into account to reflect the organic matter attachment state in the corresponding condensing device at this moment; the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing regeneration state at each moment is analyzed to obtain the relative internal and external temperature difference at each moment; based on the rate of change of the internal and external temperature difference between each moment and the adjacent moment of the condensing device in the condensing regeneration state and the degree of deviation of its distribution, the temperature gradient characteristics at each moment are calculated, and its beneficial effect is that the shedding of organic matter attachments in the condensing device in the condensing regeneration state is taken into account, and the progress of the condensing regeneration of the condensing device at this moment is reflected by the layered shedding of the organic attachments from top to bottom; based on any historical regeneration moment and the regeneration completion moment, the regeneration progress of any historical regeneration moment is determined; according to the difference between the relative internal and external temperature difference and the temperature gradient characteristics between the current moment and all its historical regeneration moments, combined with the regeneration progress, the real-time regeneration progress of the current moment is determined, and its beneficial effect is that the condensing device in the condensing regeneration state is taken into account at the current moment and the historical condensation regeneration process. The degree of organic matter shedding between the historical regeneration moments in the condensation process is determined to reflect how long it will take for the condensing device in the condensation regeneration state at the current moment to complete the regeneration of the condensing capacity; based on any historical condensation moment and the condensation completion moment, the condensation progress of any historical condensation moment is determined; according to the difference in relative condensation efficiency between the current moment and all its historical condensation moments, combined with the condensation progress, the real-time condensation progress of the current moment is determined, and its beneficial effect is that the degree of closeness of the relative condensation efficiency between the current moment and the historical condensation moments in the historical condensation process is considered, so as to reflect how long the condensing device in the condensation state at the current moment can maintain the condensation state; based on the real-time regeneration progress and the real-time condensation progress, the condensation progress error at the current moment is determined; combined with the PID algorithm, the heat medium flow in the condensing device in the condensation regeneration state at the current moment is controlled, and its beneficial effect is that the difference between the real-time condensation progress and the real-time regeneration progress is considered to reflect the asynchronous situation of the condensation process and the condensation capacity regeneration process, and the heat medium flow is controlled in real time through the PID algorithm, so that the condensation process and the condensation capacity regeneration process are carried out synchronously, thereby reducing the overall energy consumption of the condensing equipment, which is conducive to delaying the aging of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The following is a detailed description of an organic waste gas desorption and condensation treatment method of the present application in conjunction with the accompanying drawings.

[0038] Figure 1 A flow chart of the steps of a method for desorption and condensation treatment of organic waste gas provided in an embodiment of the present application;

[0039] Figure 2 A schematic diagram of the installation of a temperature sensor in a condensing device provided in an embodiment of the present application;

[0040] Figure 3 A flowchart of the steps of a method for obtaining the relative internal and external temperature difference of a condensing device in a condensing regeneration state at each moment provided in an embodiment of the present application;

[0041] Figure 4 A flowchart of a method for obtaining a condensation progress error provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of this application more clear, the following is a further detailed description of an organic waste gas desorption condensation treatment method and system proposed in this application in combination with the accompanying drawings and implementation examples. It should be understood that the specific embodiments described here are only used to explain this application and are not used to limit this application.

[0043] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0044] See also Figure 1 , which shows a flow chart of a method for desorption and condensation of organic waste gas provided by an embodiment of the present application, the method comprising the following steps:

[0045] Step 1, obtain the internal temperature sequence and external temperature sequence corresponding to the condensing equipment in the condensing state at each moment, and the internal temperature sequence and external temperature sequence corresponding to the condensing equipment in the condensing regeneration state at each moment; obtain the condensation completion time after each condensation is completed, and the regeneration completion time after each condensation regeneration is completed.

[0046] In the process of treating organic waste gas, the organic waste gas mainly includes organic waste gas transported from the outside and desorption waste gas generated by the adsorption tower. The organic waste gas contains organic substances such as styrene, vinyl acetate and butyl acrylate. The waste gas is sent into the tail gas skid buffer tank through a pipeline. The pipeline is provided with flame arrester, thermometer, pressure gauge, flow meter and other components to monitor the safety of the pipeline. A pressure alarm indicator is provided inside the buffer tank to monitor the internal pressure of the buffer tank.

[0047] The buffer tank is connected to the blower, which pressurizes the gas inside the buffer tank. When the pressure alarm indicator in the buffer tank detects that the gas pressure inside the buffer tank reaches 20kPa, the pipe valve connecting the blower to the condensation system is opened to send the organic waste gas inside the buffer tank into the condensation system.

[0048] The organic waste gas sent into the condensation system first enters the precooler and is precooled by the -40℃ purified gas of the precooler. The purified gas is refluxed from the output pipe of the subsequent condenser to realize the reuse of the condenser refrigeration resources. After precooling, the organic waste gas is input into the condensation equipment for further condensation.

[0049] After the pre-cooled organic waste gas enters the condenser, a -50°C refrigerant is input into the condensing device to generate heat exchange with the organic waste gas, so that the organic waste gas is at -40°C, and the organic matter in the organic waste gas is condensed, and the organic matter is left in the condensing system; wherein, the condensing device used in this embodiment is two sets of condensing devices A and B used alternately, and the method of alternating use is:

[0050] Condensation device A first enters the condensation state to condense the organic waste gas. During the condensation process, the condensation efficiency of condensation device A is determined in real time. When the condensation efficiency of condensation device A drops to a preset threshold, organic matter adhesion occurs in condensation device A, resulting in a decrease in condensation efficiency. At this time, heat medium is input into condensation device A to heat and liquefy the organic matter attached to the condensation pipe to remove the organic matter, so that condensation device A enters the condensation capacity regeneration state, and at the same time, condensation device B takes over condensation device A to enter the condensation state;

[0051] The condensation state refers to the state of condensing organic waste gas, in which the condensation equipment is responsible for condensing organic matter in the organic waste gas; the condensation regeneration state refers to the state of restoring the condensation capacity of the condensation equipment with low condensation efficiency, in which the condensation equipment is responsible for heating and liquefying the organic matter attached to the condensation pipe to remove the organic matter attached to the pipe surface and complete the regeneration of condensation capacity. When one of the condensation equipment is judged to have organic matter attached, resulting in a decrease in condensation efficiency, the two condensation equipments will exchange working states with each other to complete the alternating use of the condensation equipment, wherein the working states are the condensation state and the condensation regeneration state.

[0052] After the organic waste gas is condensed by the condensation equipment A or the condensation equipment B, most of the organic matter in the high-concentration organic waste gas is condensed, and the condensate treated by the condensation is gravity-flowed into the condensate tank for storage; the gas purified by the condensation equipment is input into the adsorption tower to further reduce the concentration of organic waste gas in the gas; in the adsorption process of the adsorption tower, after the adsorbent adsorbs the organic matter in the organic waste gas, it needs to be desorbed, and desorbed waste gas will be generated during the desorption process. The desorbed waste gas is transported to the buffer tank and condensed with the organic waste gas transported from the outside, thereby realizing circulation to ensure that the waste gas is completely treated.

[0053] In the above-mentioned organic waste gas treatment process, two condensing devices need to be controlled. When one condensing device enters the regeneration state, the flow control signal of the device needs to be controlled. If the flow control signal is too large, the flow of heat medium input to the condensing device will be too large, causing the expansion and wear of the condensing device to increase, and the aging of the condensing device will be accelerated. Therefore, in order to increase the service life of the equipment, the relative time of the upcoming working state conversion of the two condensing devices should be used to fully utilize the allowed time to slowly remove the organic attachments and control the flow of the condensing equipment.

[0054] Based on the above analysis, at a certain moment, when condensing device A is condensing and condensing device B is regenerating its condensing capacity, it is necessary to evaluate the condensing state of condensing device A, and then dynamically adjust the flow control signal of the heat medium in condensing device B, so that the regeneration process of condensing device B is synchronized with the condensing process of condensing device A, thereby reducing the heat medium flow of condensing device B and slowing down the aging of condensing devices. Therefore, it is necessary to evaluate the organic matter attachment of the condensing device during the condensation process and the removal of organic attachments during the condensation regeneration process.

[0055] This embodiment adopts a fixed tube plate heat exchanger as a condensing device. A temperature sensor is placed at a certain distance from the heat exchange pipe in the space where the organic waste gas of the condensing device is located. At the same time, a temperature sensor is also placed at the same level in the heat exchange pipe. In this embodiment, the installation diagram of the temperature sensor in the condensing device is as shown in FIG. Figure 2 shown.

[0056] exist Figure 2 In the figure, C1 is the inlet of organic waste gas, C2 is the outlet of purified gas, C3 is the outlet of condensate, C4 is the inlet of refrigerant or heat medium, C5 is the outlet of refrigerant or heat medium, the white area of ​​D1 is the flow area of ​​organic waste gas, the gray area of ​​D2 is the flow area of ​​refrigerant or heat medium, that is, the heat exchange pipe, the black area of ​​D3 is the baffle of the fixed tube-sheet heat exchanger, and the intersection of D4 represents the temperature sensor. A temperature sensor is installed in the heat exchange pipe D2, and a temperature sensor is also installed at the same height outside the pipe, wherein the interval between two adjacent temperature sensors in the heat exchange pipe D2 is the same.

[0057] The temperatures of all temperature sensors in the heat exchange pipes of the condensing equipment in the condensing state at each moment and the temperatures of all temperature sensors outside the heat exchange pipes are arranged in order from top to bottom according to the installation positions of the temperature sensors to form an internal temperature sequence and an external temperature sequence of the condensing equipment in the condensing state at each moment;

[0058] The temperatures of all temperature sensors in the heat exchange pipes of the condensing equipment in the condensing regeneration state at each moment and the temperatures of all temperature sensors outside the heat exchange pipes are arranged in order from top to bottom according to the installation positions of the temperature sensors to form an internal temperature sequence and an external temperature sequence of the condensing equipment in the condensing regeneration state at each moment;

[0059] Obtaining the condensation completion time after each condensation is completed, and the regeneration completion time after each condensation regeneration is completed;

[0060] Preferably, in this embodiment, the temperature sensor collects temperature data every 10 seconds, and records the collected data in a log module of the condensation system. As other implementation modes, the implementer can set them according to actual conditions.

[0061] It should be noted that, in this embodiment, it is assumed that at a certain moment, condensing device A is in a condensing state and condensing device B is in a condensing regeneration state; secondly, the temperature of the internal temperature sequence and the external temperature sequence in the same dimension represents the temperature monitored by two temperature sensors at the same level inside and outside the heat exchange pipe.

[0062] At this point, the internal temperature sequence and external temperature sequence corresponding to the condensing equipment in the condensing state at each moment, as well as the internal temperature sequence and external temperature sequence corresponding to the condensing equipment in the condensing regeneration state at each moment are obtained; the condensation completion time after each condensation is completed and the regeneration completion time after each condensation regeneration is completed are obtained.

[0063] Step 2: Determine the relative condensation efficiency at each moment based on the difference between the internal temperature sequence and the external temperature sequence of the condensing equipment in the condensing state at each moment; analyze the difference between the internal temperature sequence and the external temperature sequence of the condensing equipment in the condensing regeneration state at each moment to obtain the relative internal and external temperature difference at each moment; calculate the temperature gradient characteristics at each moment based on the rate of change of the internal and external temperature difference between each moment and the adjacent moment of the condensing equipment in the condensing regeneration state and the degree of deviation of its distribution.

[0064] Further, based on the internal temperature sequence and the external temperature sequence, the temperature difference between the inside and outside of the heat exchange pipe is analyzed to reflect the organic matter adhesion in the condensing device A in the condensing state, specifically:

[0065] The differences of the elements at the same position between the internal temperature sequence and the external temperature sequence in the condensing device in the condensing state at each moment constitute a condensation temperature difference sequence; the average value of all elements in the condensation temperature difference sequence is recorded as the heat exchange temperature difference;

[0066] Preferably, in this embodiment, the absolute value of the difference between the elements at the same position between the internal temperature sequence and the external temperature sequence in the condensing equipment that is in the condensing state at each moment constitutes a condensation temperature difference sequence; it should be noted that, for the sake of ease of understanding, it is assumed that the internal temperature sequence is [IT1, IT2, IT3, IT4], the external temperature sequence is [OT1, OT2, OT3, OT4], and the condensation temperature difference sequence is [|IT1-OT1|, |IT2-OT2|, |IT3-OT3|, |IT4-OT4|].

[0067] It should be noted that the greater the heat exchange temperature difference, the more serious the organic matter adhesion phenomenon on the heat exchange pipe in the condensing equipment A in the condensing state at this time, and the more it affects the condensation of the organic waste gas.

[0068] The ratio of the heat exchange temperature difference to the preset temperature difference threshold is used as the relative condensation efficiency at each moment;

[0069] Preferably, in this embodiment, the preset temperature difference threshold value is 10° C. As other implementation modes, the implementer can set it according to the actual situation.

[0070] It should be noted that when the relative condensation efficiency rises to 1, it means that the organic matter adhesion in the condensing device A which is in the condensing state is serious, and the condensing capacity of the condensing device A needs to be regenerated; wherein, the greater the heat exchange temperature difference, the worse the temperature exchange efficiency inside and outside the heat exchange pipe, and the temperature difference will be formed; when the heat exchange temperature difference exceeds the preset temperature difference threshold, it means that there are too many organic attachments on the surface of the heat exchange pipe, which has greatly hindered the heat exchange, and the condensing capacity needs to be regenerated.

[0071] Based on the above analysis, the relative condensation efficiency can be used to determine the organic matter adhesion status of the condensing device A in the condensing state. Secondly, it is necessary to evaluate the regeneration progress of the condensing device B in the condensing regeneration state to ensure that the condensing capacity regeneration process of the condensing device B in the condensing regeneration state and the condensation process of the condensing device A in the condensing state are carried out synchronously, thereby reducing the heat medium flow of the condensing device B and slowing down the aging of the equipment.

[0072] For the condensing device B in the condensing regeneration state, the organic matter is removed by injecting heat medium into the fixed plate heat exchanger. The faster the heat medium is injected, the greater the organic matter removal force on the condensing device B. As the condensing capacity regeneration process proceeds, the organic attachments fall off, and the temperature difference monitored by the two temperature sensors at the same height installed on the fixed plate heat exchanger gradually decreases. Therefore, the regeneration progress of the condensing device B in the condensing regeneration state can be evaluated through the internal temperature sequence and the external temperature sequence.

[0073] The condensation regeneration process of condensing equipment B can be roughly divided into two stages. The first is the overall heating stage. In this stage, the organic attachments on the heat exchange pipe are heated by the heat medium, and the temperature sensor can detect that the temperature difference between the inside and outside of the heat exchange pipe is gradually decreasing. As the organic attachments are affected by the heating, the attachments gradually melt and fall off. This stage is recorded as the attachment liquefaction stage; because the liquefaction and shedding of the attachments on the upper layer will affect the liquefaction and shedding of the attachments on the lower layer, the temperature difference between the sensors inside and outside the upper heat exchange pipe will decrease faster in this process, and the regeneration progress of the upper layer will be faster, while the regeneration progress of the lower layer will be slower. Based on this analysis, the temperature difference monitored by the temperature sensor at the same height at each moment is analyzed to determine the relative internal and external temperature difference to reflect the stage of the condensing equipment B in the condensation regeneration process, and then explain the regeneration progress of the condensing equipment B. The step flow chart of the method for obtaining the relative internal and external temperature difference of the condensing equipment in the condensation regeneration state at each moment provided in the embodiment of the present application is as follows Figure 3 As shown, specifically including:

[0074] Based on the control input in the condensing system, the heating medium temperature and the cooling medium temperature of the condensing system input are obtained;

[0075] It should be noted that the heat medium temperature and the refrigerant temperature are the temperatures of the heat medium and the refrigerant before entering the heat exchange pipe, respectively. The temperatures are controlled by an external energy storage device, and the heat medium temperature and the refrigerant temperature are fixed values.

[0076] The difference between the temperature of the heating medium and the temperature of the cooling medium is recorded as the maximum temperature difference;

[0077] The difference between the internal temperature sequence and the external temperature sequence in the condensing device in the condensing regeneration state at each moment forms a regeneration temperature difference sequence;

[0078] The average value of all elements in the regeneration temperature difference sequence is recorded as the condensation regeneration temperature difference;

[0079] Preferably, in this embodiment, the absolute value of the difference between the internal temperature sequence and the external temperature sequence in the condensing device in the condensing regeneration state at each moment constitutes a regeneration temperature difference sequence.

[0080] The ratio of the condensation regeneration temperature difference at each moment to the maximum temperature difference is used as the relative internal and external temperature difference of the condensing device in the condensation regeneration state at each moment;

[0081] It should be noted that the smaller the relative internal and external temperature difference is, the lower the heating temperature of the organic attachments of the condensing device B which is in the condensation regeneration state is, the higher the degree of organic attachments falling off is, and the higher the completion degree of the condensing capacity regeneration progress of the condensing device B is.

[0082] Furthermore, during the overall heating stage of the condensation regeneration process of the condensation equipment B, the temperature difference between the inside and outside of the heat exchange pipe of the condensation equipment B is large, and the temperature difference distribution from top to bottom is relatively uniform. Therefore, at this time, the temperature difference between the inside and outside of the heat exchange pipe can better reflect the recovery of the condensation regeneration progress; while in the liquefaction stage of the attachments, the temperature difference between the inside and outside of the heat exchange pipe gradually decreases, and because the organic attachments that fall off from the upper layer will hinder the falling off of the organic attachments in the lower layer, the temperature difference between the inside and outside of the heat exchange pipe in the condensation equipment B is small, and the temperature difference distribution between the upper and lower layers is uneven. At this time, there is a large error in reflecting the falling off of organic attachments in the condensation equipment B through the relative inside and outside temperature difference. Therefore, it is necessary to further combine the changing rate of the temperature inside and outside the heat exchange pipe to analyze the condensation regeneration progress of the condensation equipment B.

[0083] Since the upper organic attachments fall off faster than the lower ones, the temperature change rate of the upper heat exchange pipe is faster than that of the lower ones at the beginning. As the upper organic attachments fall off completely, the temperature change rate of the upper pipe gradually approaches 0, and the pipe position corresponding to the faster temperature change rate gradually moves downward. The progress of organic attachment falling off in the attachment liquefaction stage can be judged by the position distribution of the temperature change rate of the heat exchange pipe on the pipe, specifically:

[0084] The difference between the regeneration temperature difference sequence at each moment and the previous moment is used to form a temperature difference speed sequence;

[0085] It should be noted that the obtained temperature difference velocity sequence reflects the stratification and shedding characteristics of organic attachments on the heat exchange pipe during the regeneration process of the condensing capacity of the condensing equipment B. The larger the hth element in the temperature difference velocity sequence, the faster the shedding speed of the organic attachments at the position of the hth temperature sensor.

[0086] Calculate the skewness of the temperature difference speed sequence as the temperature gradient characteristic of the condensing device in the condensation regeneration state at each moment, wherein if the skewness is less than a preset first value, the temperature gradient characteristic is assigned a preset first value, and if the skewness is greater than a preset second value, the temperature gradient characteristic is assigned a preset second value, wherein the preset first value is less than the preset second value;

[0087] It should be noted that the preset first numerical value is -1, and the preset second numerical value is 1. As other implementation modes, the implementer can set them according to actual conditions. Since the value range of the skewness is (-∞, +∞), if the skewness is less than -1, the temperature gradient characteristic is assigned a value of -1; if the skewness is greater than 1, the temperature gradient characteristic is assigned a value of 1; if the skewness is greater than -1 and less than 1, the temperature gradient characteristic is the corresponding skewness. Therefore, the value range of the temperature gradient characteristic is [-1, 1].

[0088] It should be noted that, the smaller the temperature gradient feature is, the greater the element value on the left in the temperature difference velocity sequence is than the element value on the right, indicating that the organic attachments on the upper layer of the heat exchange pipe fall off faster, indicating that the condensing device B is more in the initial stage of the attachment liquefaction stage at this time; conversely, the larger the temperature gradient feature is, the greater the element value on the right in the temperature difference velocity sequence is than the element value on the left, indicating that the organic attachments on the lower layer of the heat exchange pipe surface fall off faster, indicating that the condensing device B is more likely to be in the final stage of the attachment liquefaction stage at this time.

[0089] At this point, the relative condensation efficiency of the condensing device in the condensing state at each moment, and the relative internal and external temperature difference and temperature gradient characteristics of the condensing device in the condensing regeneration state at each moment are obtained.

[0090] Step 3, based on any historical regeneration moment and the regeneration completion moment, determine the regeneration progress of any historical regeneration moment; according to the difference in the relative internal and external temperature difference and the temperature gradient characteristics between the current moment and all its historical regeneration moments, combined with the regeneration progress, determine the real-time regeneration progress of the current moment.

[0091] Based on the above analysis, the larger the relative temperature difference between the inside and outside, the more likely the heat exchanger is in the overall heating stage; the smaller the relative temperature difference between the inside and outside, the more likely the heat exchanger is in the attachment liquefaction stage. Therefore, the condensing capacity regeneration stage of the heat exchanger is judged by the temperature difference between the inside and outside of the heat exchange pipe, and the temperature characteristic weight is determined to reflect whether the condensing equipment B is in the overall heating stage or the attachment liquefaction stage.

[0092] All the moments in the multiple condensation regeneration process of the condensing equipment before the current moment are recorded as each historical regeneration moment;

[0093] Preferably, in this embodiment, all moments in the condensation regeneration process of the condensing device for 10 times before the current moment are recorded as historical regeneration moments. As other implementation methods, the implementer can set them according to the actual situation.

[0094] It should be noted that, assuming that a condensation regeneration process takes T1 time from the start of condensation regeneration to the completion of condensation regeneration, since the temperature is collected every 10 seconds, there is a historical regeneration moments; secondly, if the total number of condensing capacity regeneration processes before the current moment is greater than or equal to 1 and less than 10, all moments in all condensing capacity regeneration processes are obtained and recorded as historical regeneration moments; if the total number of condensing capacity regeneration processes before the current moment is less than 1, it means that the condensing system is in the initialization stage, and the condensing capacity regeneration process is manually controlled by technical personnel, and the method described in this embodiment is not applicable to control the flow signal.

[0095] Based on the internal temperature sequence and the external temperature sequence of the condensing device at any historical regeneration moment during each condensation regeneration process, the relative internal and external temperature difference and the temperature gradient characteristics at any historical regeneration moment are calculated;

[0096] The time interval between any historical regeneration moment and the regeneration completion moment in each condensation regeneration process is recorded as the regeneration progress of any historical regeneration moment;

[0097] Further, based on the difference between the relative internal and external temperature difference and the temperature gradient characteristics corresponding to the current moment and the historical regeneration moment, the temperature characteristic similarity is determined, specifically:

[0098] The relative internal and external temperature difference of the condensing device in the condensing regeneration state at the current moment is used as the temperature feature weight at the current moment;

[0099] The calculation method of the temperature characteristic similarity between the current moment and any of the historical regeneration moments is: Among them, DT t→g is the temperature characteristic similarity between the current time t and the g-th historical regeneration time, γ t is the relative internal and external temperature difference of the condensing equipment in the condensing regeneration state at the current time t, γ g is the relative internal and external temperature difference at the g-th historical regeneration moment, δ t is the temperature gradient characteristic of the condensing equipment in the condensing regeneration state at the current time t, δ g is the temperature gradient characteristic at the g-th historical regeneration moment, ε t is the temperature characteristic weight of the condensing device in the condensing regeneration state at the current time t, τ is a preset value greater than 0 to avoid the denominator being 0, and the value range of τ is (0, 1]. In this embodiment, τ is 0.1. As other implementation methods, the implementer can set it according to the actual situation.

[0100] It should be noted that the temperature characteristic similarity DT t→g The larger it is, the smaller the difference between the temperature characteristics corresponding to the g-th historical regeneration moment and the current moment t is, reflecting that the condensation regeneration progress of the condensing equipment in the condensation regeneration state at the current moment t is closer to the regeneration progress at the g-th historical regeneration moment.

[0101] Normalizing the similarity of the temperature characteristics at the current moment and all historical regeneration moments, and taking a weighted sum of the regeneration progress at all historical regeneration moments and the normalized result as the real-time regeneration progress at the current moment;

[0102] Preferably, in this embodiment, the normalization method is: calculate the sum of the temperature feature similarities between the current moment and all historical regeneration moments, and use the ratio of the temperature feature similarity to the sum as the normalization result of the current moment and any historical regeneration moment.

[0103] It should be noted that the calculation method of the weighted summation is a well-known technique and will not be described in detail here.

[0104] It should be noted that the similarity of the temperature characteristics is large, which means that the smaller the difference between the heat exchanger temperature characteristics of the condensing equipment in the condensing regeneration state at the current time t and the historical condensing regeneration time, the smaller the difference, the larger the value with the normalized result as the weight; the real-time regeneration progress at the current time t is evaluated by the regeneration progress corresponding to the historical regeneration time with small temperature characteristic difference, and the regeneration progress of the condensing equipment B in the condensing regeneration state is estimated; secondly, the real-time regeneration progress at the current time t is estimated by the temperature characteristics of the historical moments in the historical condensation regeneration process, which is conducive to accurately judging the regeneration status of the condensing capacity of the current condensing equipment B, and is conducive to dynamically adjusting the flow control signal according to the regeneration status of the condensing capacity in the future, so as to avoid excessive heat medium flow causing equipment aging, or to avoid excessive heat medium flow so that the condensing equipment B cannot replace the condensing equipment A in time for condensation processing.

[0105] At this point, the real-time regeneration progress at the current moment is obtained.

[0106] Step 4, based on any historical condensation moment and the condensation completion moment, determine the condensation progress of any historical condensation moment; according to the difference in relative condensation efficiency between the current moment and all historical condensation moments, combined with the condensation progress, determine the real-time condensation progress of the current moment.

[0107] Further, the real-time regeneration progress reflects the recovery of the condensing capacity of the condensing device in the condensing regeneration state; based on the relative condensing efficiency of the condensing device at each moment in each condensing process before the current moment, the real-time condensing progress is determined to reflect the condensing capacity of the condensing device in the condensing state, specifically:

[0108] All the moments in the multiple condensation processes of the condensation equipment before the current moment are recorded as each historical condensation moment;

[0109] Preferably, in this embodiment, all moments in the 10 condensation processes performed by the condensation device before the current moment are recorded as each historical condensation moment.

[0110] It should be noted that, assuming that a condensation process takes T2 time from the start to the completion of condensation, since the temperature is collected every 10 seconds, there is a historical condensation moments; secondly, if the total number of condensation processes before the current moment is greater than or equal to 1 and less than 10, all moments in all condensation processes are obtained and recorded as historical condensation moments; if the total number of condensation processes before the current moment is less than 1, it means that the condensation system is in the initialization stage, and the condensation process is manually controlled by technicians, and the method described in this embodiment is not applicable to control the flow signal.

[0111] Based on the internal temperature sequence and the external temperature sequence of the condensing device at any historical condensation moment in each condensation process, calculating the relative condensation efficiency at any historical condensation moment;

[0112] The time interval between any historical condensation moment and the condensation completion moment in each condensation process is recorded as the condensation progress of any historical condensation moment;

[0113] Further, based on the difference between the relative condensation efficiency between the current moment and the historical condensation moment, combined with the condensation progress, the real-time condensation progress is determined, specifically:

[0114] The calculation method of the real-time condensation progress at the current moment is: Among them, Fr t is the real-time condensation progress at the current time t, F s is the condensation progress at the sth historical condensation moment, β s is the relative condensation efficiency at the sth historical condensation moment, β t is the relative condensation efficiency at the current time t, S t is the number of all historical condensation moments corresponding to the current moment t, ∈ is a preset value greater than 0 to avoid the denominator being 0, the value range of τ is (0, 1]. In this embodiment, τ is 0.1. As other implementation methods, the implementer can set it according to the actual situation, and norm() is the normalization function.

[0115] Preferably, in this embodiment, the current moment and the sth historical condensation moment are Recorded as condensation difference; calculate the cumulative sum of the condensation differences between the current moment and all historical condensation moments, and use the ratio of the condensation difference to the cumulative sum as the normalized value between the current moment and the sth historical condensation moment, that is, the calculation formula of the normalized value is:

[0116] It should be noted that if the difference in relative condensation efficiency between the current time t and the sth historical condensation time is smaller, the normalized value The larger the weight value is, the more similar the condensing capacity of the condensing equipment in the condensing state at the current time t is to the condensing state at the historical condensing time, that is, the condensing progress of the condensing equipment in the condensing state at the current time t is closer to the condensing progress at the g-th historical condensing time; using the condensing progress at the historical condensing time with small condensation difference to estimate the real-time condensing progress at the current time t is conducive to accurately judging the condensing capacity of the condensing equipment A currently in the condensing state, and is conducive to subsequently comparing the condensing progress of the condensing equipment A with the regeneration progress of the condensing equipment B, and then controlling the flow signal.

[0117] At this point, the real-time condensation progress at the current moment is obtained.

[0118] Step 5: Determine the condensation progress error at the current moment based on the real-time regeneration progress and the real-time condensation progress; and control the heat medium flow in the condensing device that is in the condensation regeneration state at the current moment in combination with the PID algorithm.

[0119] Further, based on the difference between the real-time regeneration progress and the real-time condensation progress, the difference in the working progress of the two condensing devices is evaluated, and the condensation progress error is determined to reflect the degree of synchronization between the condensation progress of the condensing device A and the regeneration progress of the condensing device B, specifically:

[0120] The calculation method of the condensation progress error at the current moment is: J t =Dr t -(Fr t +M), where J t is the condensation progress error at the current time t, Dr t is the real-time regeneration progress at the current time t, Fr t is the real-time condensation progress at the current time t, and M is the preset redundant time.

[0121] Preferably, in this embodiment, the preset redundancy time is set to 10 minutes. As other implementation modes, the implementer can set it according to the actual situation.

[0122] It should be noted that the difference between the real-time regeneration progress and the real-time condensation progress Dr t -Fr t , reflects the difference in work progress between condensing equipment B and condensing equipment A, where Dr t -Fr t If the difference is positive, it means that the real-time regeneration progress of condensing device B is faster than the real-time condensing progress of condensing device A. At this time, the heat medium flow in condensing device B is too large and the heat medium flow needs to be reduced; on the contrary, Dr t -Fr tis a negative number, it is necessary to increase the heat medium flow in the condensing device B; secondly, the purpose of the preset redundant time is to allow the condensing capacity regeneration process of the condensing device B to be completed before the condensing process of the condensing device A, leaving enough redundant time to avoid the condensing process of the condensing device A being suddenly accelerated due to the change of the system environment when the condensing capacity regeneration process of the condensing device B has not been completed, so that the condensing process of the condensing device A is completed in advance, resulting in the condensing device B being unable to replace the condensing device A for condensation processing; at the same time, when the condensation control system operates the two condensing devices to switch the progress, there is enough redundant time for the switching process. The flowchart of the method for obtaining the condensation progress error provided by this embodiment is as follows Figure 4 shown.

[0123] Further, based on the condensation progress error, the heat medium flow is controlled by PID (Proportional Integral Derivative) algorithm control, specifically:

[0124] The condensation progress error is used as the input of the PID algorithm, and the output is a flow control signal of the heat medium flow. The condensation system controls the heat medium flow in the condensing device B which is currently in the condensation regeneration state according to the flow control signal, thereby reducing the overall energy consumption and delaying the aging of the equipment.

[0125] Preferably, in this embodiment, the proportional coefficient in the PID algorithm is 0.7, the integral coefficient is 0.05, and the differential coefficient is 50. As other implementation methods, the implementer can set them according to actual conditions; secondly, the PID algorithm is a well-known technology and will not be described here.

[0126] Based on the same inventive concept as the above method, an embodiment of the present application also provides an organic waste gas desorption and condensation treatment system, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of any one of the above-mentioned organic waste gas desorption and condensation treatment methods are implemented.

[0127] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0128] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the present application. It should be pointed out that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application without departing from the content of the technical solution of the present application, shall fall within the protection scope of the technical solution of the present application.

Claims

1. A method for treating organic waste gas by desorption and condensation, characterized in that: The method comprises the following steps: Obtain the internal temperature sequence and external temperature sequence corresponding to the condensing device in the condensing state at each moment, and the internal temperature sequence and external temperature sequence corresponding to the condensing device in the condensing regeneration state at each moment; obtain the condensation completion time after each condensation is completed, and the regeneration completion time after each condensation regeneration is completed; Based on the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing state at each moment, the relative condensing efficiency at each moment is determined; the difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing regeneration state at each moment is analyzed to obtain the relative internal and external temperature difference at each moment; based on the rate of change of the internal and external temperature difference between each moment and the adjacent moment of the condensing device in the condensing regeneration state and the degree of deviation of its distribution, the temperature gradient characteristics at each moment are calculated; All moments in the multiple condensation processes and all moments in the multiple condensation regeneration processes of the condensing device before the current moment are recorded as each historical condensation moment and each historical regeneration moment respectively; based on any historical condensation moment and the condensation completion moment, any historical regeneration moment and the regeneration completion moment, the condensation progress of any historical condensation moment and the regeneration progress of any historical regeneration moment are determined respectively; Determine the real-time regeneration progress at the current moment according to the relative internal and external temperature difference and the difference in temperature gradient characteristics between the current moment and all historical regeneration moments, combined with the regeneration progress; Determine the real-time condensation progress at the current moment according to the difference in relative condensation efficiency between the current moment and all historical condensation moments and the condensation progress; Based on the real-time regeneration progress and the real-time condensation progress, the condensation progress error at the current moment is determined, and combined with the PID algorithm, the heat medium flow in the condensing device that is in the condensation regeneration state at the current moment is controlled.

2. The method for desorption and condensation of organic waste gas according to claim 1, characterized in that: Determining the relative condensation efficiency at each moment includes: The difference between the internal temperature sequence and the external temperature sequence of the condensing device in the condensing state at each moment is used to form a condensing temperature difference sequence; the average value of all elements in the condensing temperature difference sequence is recorded as the heat exchange temperature difference; The ratio of the heat exchange temperature difference at each moment to the preset temperature difference threshold is used as the relative condensation efficiency at each moment.

3. The method for desorption and condensation of organic waste gas according to claim 1, characterized in that: The relative internal and external temperature differences at each moment are obtained, including: Based on the control input in the condensing system, the heat medium temperature and the refrigerant temperature of the condensing system input are obtained; and the difference between the heat medium temperature and the refrigerant temperature is recorded as the maximum temperature difference; The difference between the internal temperature sequence and the external temperature sequence in the condensing device in the condensing regeneration state at each moment constitutes a regeneration temperature difference sequence; the average value of all elements in the regeneration temperature difference sequence is recorded as the condensation regeneration temperature difference; The ratio of the condensation regeneration temperature difference at each moment to the maximum temperature difference is taken as the relative internal and external temperature difference at each moment.

4. The method for desorption and condensation of organic waste gas according to claim 3, characterized in that: The calculation method of the temperature gradient characteristics at each moment is: The difference between the regeneration temperature difference sequence at each moment and the previous moment is used to form a temperature difference speed sequence; The skewness of the temperature difference velocity sequence is calculated as the temperature gradient characteristic at each moment, wherein if the skewness is less than a preset first value, the temperature gradient characteristic is assigned a preset first value, and if the skewness is greater than a preset second value, the temperature gradient characteristic is assigned a preset second value, wherein the preset first value is less than the preset second value.

5. The method for desorption and condensation of organic waste gas according to claim 1, characterized in that: The determining of the condensation progress at any historical condensation moment and the regeneration progress at any historical regeneration moment includes: The time interval between any historical condensation moment and the condensation completion moment in each condensation process is used as the condensation progress of any historical condensation moment; The time interval between any historical regeneration moment and the regeneration completion moment in each condensation regeneration process is used as the regeneration progress of any historical regeneration moment.

6. The method for treating organic waste gas by desorption and condensation according to claim 1, characterized in that: Determining the real-time regeneration progress at the current moment includes: The relative internal and external temperature difference of the condensing device in the condensing regeneration state at the current moment is used as the temperature feature weight at the current moment; The calculation method of the temperature characteristic similarity between the current moment and any of the historical regeneration moments is: Among them, DT t→g is the temperature characteristic similarity between the current time t and the g-th historical regeneration time, γ t is the relative internal and external temperature difference of the condensing equipment in the condensing regeneration state at the current time t, γ g is the relative internal and external temperature difference at the g-th historical regeneration moment, δ t is the temperature gradient characteristic of the condensing equipment in the condensing regeneration state at the current time t, δ g is the temperature gradient characteristic at the g-th historical regeneration moment, ε t is the temperature characteristic weight of the condensing device in the condensing regeneration state at the current time t, and τ is a preset value greater than 0; The temperature characteristic similarity between the current moment and all historical regeneration moments is normalized, and the regeneration progress of all historical regeneration moments and the normalized result are weighted summed as the real-time regeneration progress of the current moment.

7. The method for desorption and condensation of organic waste gas according to claim 1, characterized in that: Real-time condensation progress Fr at the current time t t The calculation method is: Among them, F s is the condensation progress at the sth historical condensation moment, β s is the relative condensation efficiency at the sth historical condensation moment, β t is the relative condensation efficiency at the current time t, S t is the number of all historical condensation moments corresponding to the current moment t, and ∈ is a preset value greater than 0.

8. The method for treating organic waste gas by desorption and condensation according to claim 1, characterized in that: The condensation progress error J at the current time t t The calculation method of J is: t =Dr t -(Fr t +M), where Dr t is the real-time regeneration progress at the current time t, Fr t is the real-time condensation progress at the current time t, and M is the preset redundant time.

9. The method for desorption and condensation of organic waste gas according to claim 1, characterized in that: The controlling of the heat medium flow rate in the condensing device which is currently in the condensing regeneration state includes: The condensation progress error is used as the input of the PID algorithm, and the output is a flow control signal of the heat medium flow. The condensation system adjusts and controls the heat medium flow in the condensing device that is currently in the condensation regeneration state according to the flow control signal.

10. An organic waste gas desorption and condensation treatment system, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the organic waste gas desorption and condensation treatment method as described in any one of claims 1 to 9 are implemented.

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