Zeolite adsorption and desorption integrated treatment system

Abstract

The invention discloses a zeolite adsorption and desorption integrated treatment system, and particularly relates to the field of zeolite separation treatment, and the zeolite adsorption and desorption integrated treatment system comprises a process sensing module, a dynamic partition control module, a global optimization control module and a cooling regeneration module. According to the zeolite adsorption and desorption integrated treatment system, the problem of blind operation in the traditional technology is solved through the process sensing module, a data basis is provided for dynamic partition, the intelligent monitoring level is improved, and the performance of an adsorbent is fully exerted; the problem of non-uniform heat and mass transfer of a bed layer is effectively solved through the dynamic partition control module, the desorption heat utilization efficiency is improved, and meanwhile, the service life of an adsorbent is prolonged; a dynamic optimization function is constructed through the global optimization control module, energy consumption, solvent recovery income and stability are comprehensively considered, self-adaptive adjustment of operation parameters is achieved, the energy consumption is reduced while the processing efficiency is guaranteed, and the environmental benefits are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of zeolite separation and treatment technology, and more specifically, to an integrated zeolite adsorption and desorption treatment system. Background Technology

[0002] With the increasing demand for industrial waste gas treatment and resource recovery, the efficient and low-energy capture and recovery of volatile organic compounds and low-concentration valuable gases is particularly important in environmental protection and ecological protection engineering construction. Traditional technologies achieve pollutant capture through the cyclical batch principle of adsorption, pause, and desorption. However, practice has shown that there are significant technical bottlenecks: the adsorption and desorption processes are separated in time and space, resulting in discontinuous systems and large footprints, which restricts their application in intensive environmental protection projects. The desorption process requires heating the entire adsorbent bed and device shell from ambient temperature to a high desorption temperature, resulting in huge heat energy consumption, a considerable portion of which is used to heat the device structure that does not participate in mass transfer, causing energy waste.

[0003] To overcome the core defects of high energy consumption and low efficiency in traditional technologies, existing technologies have developed artificial zeolite molecular sieves with multi-level pore structures or modified high-efficiency activated carbon. By precisely controlling the zeolite framework or chemically modifying the surface of activated carbon, the materials are endowed with strong hydrophobicity and precise pores that match the target molecular size, thereby improving separation selectivity and achieving higher gas separation efficiency and faster desorption kinetics per unit material. This has promoted the basic application of high-performance adsorbents in environmental protection equipment.

[0004] However, in practical use, it still has some shortcomings. For example, the use of high-performance zeolite or high-efficiency activated carbon cannot match the rapid adsorption or desorption characteristics of advanced adsorbents, which means that the high performance potential of adsorbents cannot be fully utilized at the level of environmental engineering systems. Specifically, despite the use of fixed-bed reactor configuration and its split design, there are still problems such as uneven heat and mass transfer in the bed and low desorption heat utilization efficiency, which directly affect the core economic and stability indicators of system operation. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides an integrated zeolite adsorption and desorption treatment system, which solves the problems mentioned in the background art through the following solutions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A zeolite adsorption-desorption integrated treatment system, comprising: Process sensing module: used to acquire the state of the adsorption bed in real time and generate a first processing dataset characterizing the adsorption load distribution and penetration front; Dynamic partitioning control module: Based on the first processing dataset, the adsorption bed is dynamically divided into at least one deep saturated adsorption zone and one high-efficiency adsorption zone, and pulsed high-temperature desorption is performed on the deep saturated adsorption zone to obtain a second processing dataset characterizing the state of each partition. Global optimization control module: used to receive the first processing dataset and the second processing dataset, and output a third processing dataset through a global optimization control algorithm. The third processing dataset is used to send control commands to the cooling regeneration module to adjust the adsorption cycle, desorption cycle, partition switching and fluid parameters. Cooling and regeneration module: In response to the desorption completion signal from the dynamic partition control module and the control command from the global optimization control module, the module cools and purges the desorbed adsorption bed region and feeds back the bed ready signal to the global optimization control module.

[0007] Preferably, the process-aware module, in its first processing dataset, includes at least: The adsorption load distribution map, which characterizes the adsorption state distribution, is output in the form of structured data containing the boundary coordinates of the partitions and the quantified saturation values ​​of each region. It is used to quantify the local adsorption load saturation at different locations inside the bed. The frontier prediction information characterizing the dynamic evolution of the process includes at least the predicted time point when the bed outlet concentration reaches the preset breakthrough threshold, as well as the movement speed of the adsorption front and the frontier prediction curve. Quantitative information characterizing the state of key regions includes at least the average saturation value and the real-time adsorption rate.

[0008] Preferably, the dynamic partition control module includes at least a partition control first unit, a partition control second unit, and a partition control third unit; The partition control first unit is configured to dynamically divide the adsorption bed into a deep saturation adsorption zone and a fine adsorption zone based on the first processed dataset by airflow guidance, and output the partition status information to the partition control second unit and the global optimization control module. The second partition control unit is configured to respond to a desorption start command from the first partition control unit and use the heat recovered from the third partition control unit to perform reverse pulse desorption on the deep saturated adsorption zone, and output the desorption products to the third partition control unit. The third partition control unit is configured to recover the high-grade heat of the desorption products and feed it back to the second partition control unit, condense and recover the organic solvent, and send the generated low-grade tail gas back to the inlet of the first partition control unit.

[0009] Preferably, the dynamic zoning control module, wherein the first zoning control unit executes the dynamic division of the adsorption bed into at least one deep saturation adsorption zone and one high-efficiency adsorption zone, specifically includes: Based on each location in the adsorption load distribution map of the first processed dataset saturation value Apply the preset partitioning rules: Will All continuous regions are classified as deep saturated adsorption regions, and their spatial coordinate boundaries are defined. It has been decided, among which, This is represented as the depth saturation determination threshold; Will The area is classified as the precision adsorption zone, among which, This is expressed as the lower limit threshold for determining precise adsorption. Based on the spatial coordinate boundary of the deep saturated adsorption zone, the corresponding numbers of one or more intake or exhaust control valves are mapped to generate a zone control command containing a list of shut-off valves and a list of open valves.

[0010] Preferably, the dynamic partition control module, specifically the partition control second unit, is used to execute: The heat recovered from the third unit of the partition control is used to preheat the desorbed fresh air in the first stage; The heater is activated to generate pulsed high-temperature hot air in the opposite direction to the adsorption airflow, and precisely guided to the deep saturated adsorption zone defined by the first zone control unit for desorption. The pulsed high-temperature desorption performed on the deep saturated adsorption zone has a desorption hot air flow direction opposite to the airflow direction during the adsorption stage.

[0011] Preferably, the dynamic zoning control module, the third zoning control unit includes a high-efficiency heat exchanger, a condensation recovery device and an exhaust gas circulation pipeline; The high-efficiency heat exchanger is configured to recover high-grade heat from the desorption product gas to preheat the desorption fresh air entering the second unit of the zone control. The condensation and recovery device is configured to condense and separate the organic solvent in the desorption product gas after heat exchange and cooling. The exhaust gas recirculation pipeline is configured to guide the condensed low-grade exhaust gas back to the inlet of the adsorption bed for preheating the waste gas to be treated or forming a protective gas curtain.

[0012] Preferably, the global optimization control module, in each optimization cycle, solves a solution based on the overall operating cost. The dynamic optimization function with the objective of minimization is specifically expressed as: ,in, Represented as time Instantaneous energy consumption cost This is expressed as the predicted solvent recovery benefit. This is represented as an unstable penalty term. This represents the time length in which the model predicts the future. Indicates the current time. Expressed as a unit value conversion factor, This is represented as the penalty term weight coefficient.

[0013] Preferably, in the global optimization control module, the instability penalty term Specifically, it is expressed as: , in, This is expressed as the adsorption bed saturation. Variance in space, This is expressed as the predicted exhaust gas outlet concentration. This is expressed as the pollutant emission concentration threshold. and These represent the highest and optimal temperatures of the bed, respectively. , , These represent the severity of penalties for the three unstable factors: inhomogeneity, penetration risk, and temperature deviation.

[0014] The technical effects and advantages of this invention are as follows: 1. This invention uses a process sensing module to monitor and obtain the state of the adsorption bed in real time, and generates an adsorption load distribution map, front prediction information and key area quantitative information. This solves the problem of blind operation in traditional technology, provides a data foundation for dynamic zoning, improves the level of intelligent monitoring, and enables the adsorbent performance to be fully utilized. 2. The present invention uses a dynamic partitioning control module to dynamically divide the adsorption bed into a deep saturation zone and a fine adsorption zone based on the first processing dataset. Pulsed high-temperature reverse desorption is performed on the deep saturation zone, which effectively solves the problem of uneven heat and mass transfer in the bed, improves the desorption heat utilization efficiency, and extends the service life of the adsorbent. 3. This invention constructs a dynamic optimization function through a global optimization control module, taking into account energy consumption, solvent recovery benefits and stability, and realizes adaptive adjustment of operating parameters. While ensuring processing efficiency, it reduces energy consumption and significantly improves environmental benefits. Attached Figure Description

[0015] Figure 1 This is a block diagram of a zeolite adsorption-desorption integrated treatment system provided according to an embodiment of this application.

[0016] Figure 2 This is a unit block diagram of a dynamic zoning control module in a zeolite adsorption-desorption integrated treatment system provided in an embodiment of this application. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The terminology used in the following embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to include the plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this application refers to and includes any or all possible combinations of one or more of the listed items.

[0019] Hereinafter, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first," "second," and "third" may explicitly or implicitly include one or more of that feature, and in the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0020] As attached Figure 1 The zeolite adsorption-desorption integrated treatment system shown includes a process sensing module, a dynamic zone control module, a global optimization control module, and a cooling and regeneration module.

[0021] The process sensing module is used to acquire the state of the adsorption bed in real time and generate a first processing dataset that characterizes the adsorption load distribution and the penetration front. The first processing dataset includes at least an adsorption load distribution map characterizing the adsorption state distribution, a front prediction characterizing the dynamic evolution of the process, quantitative information characterizing the state of key regions, and at least an average saturation value and a real-time adsorption rate.

[0022] Specifically, the process sensing module includes an intake parameter sensing layer, a bed state sensing layer, and a data processing unit. The intake parameter sensing layer is deployed at the front end of the intake manifold or intake distributor of the adsorption bed to capture the original operating conditions of the waste gas entering the system. The bed state sensing layer uses a sensor network arranged at different depths and radial positions inside the adsorption bed to acquire real-time temperature and concentration distribution data of the bed. The data processing unit is used to generate the first processed dataset based on the data acquired by the intake parameter sensing layer and the bed state sensing layer.

[0023] In this embodiment, the components of the intake parameter sensing layer include, but are not limited to, a mass flow meter, a non-dispersive infrared or photoionization VOCs concentration sensor, a thermocouple or platinum resistance thermometer, used to monitor data including at least the exhaust gas volume flow rate, VOCs inlet concentration, and exhaust gas inlet temperature; the bed state sensing layer uses a miniaturized, high-temperature resistant distributed thermocouple array for temperature monitoring, and can use distributed fiber optic grating sensors for local concentration monitoring. The sensors are arranged in a matrix strategy with multiple axial layers and multiple radial points: axially, sensor rings are arranged at least three key depth sections along the airflow direction at the bed inlet, middle, and near the outlet; radially, measuring points are arranged at least at the bed center, midpoint of the radius, and near the wall in each axial section to capture radial differences caused by uneven airflow distribution; the acquired data includes at least the axial and radial temperature distribution of the bed, the axial and radial VOCs concentration distribution, and the outlet concentration at key locations.

[0024] Furthermore, in the data processing unit, the raw signals acquired by the intake parameter sensing layer and the bed state sensing layer are filtered, aligned, and normalized to output a synchronized standardized spatiotemporal dataset; then, parallel calculations are performed using the gas phase concentration in the standardized dataset. ,temperature Spatial data is used to calculate the initial value of local adsorption load saturation at each discrete measuring point. By using Kriging interpolation, discrete sensor point data are reconstructed to generate a continuous adsorption load. The distribution field is analyzed, and an adsorption load distribution map is generated in real time. The adsorption load distribution map is output in the form of structured data containing the coordinates of the partition boundaries and the quantified saturation values ​​of each region, which is used to quantify the local adsorption load saturation at different locations inside the bed. Standardized datasets and adsorbent performance parameters are used as inputs to a preset breakthrough front prediction model to dynamically predict the time point at which the bed outlet concentration will reach a preset breakthrough threshold. It also measures the speed and shape of the adsorption front and outputs information including the breakout time forecast and the front prediction curve.

[0025] It should be noted that the local adsorption load saturation is... Target location The mass of VOCs adsorbed by the adsorbent Its theoretical equilibrium adsorption capacity under current operating conditions The ratio; in this embodiment, in time Current gas phase concentration and temperature Under these conditions, its calculation can be expressed as: Wherein, the theoretical equilibrium adsorption capacity Determined by a preset adsorption isotherm model; in this embodiment, for zeolite adsorbents, an adsorption isotherm model can be used, specifically expressed as follows: ,in, This is expressed as the maximum adsorption capacity. Expressed as an equilibrium constant, it is used to evaluate the characteristics of the adsorption process, reflecting the strength of the interaction between the adsorbate and the adsorbent and the degree of reversibility of adsorption. The temperature correction factor is expressed as a value determined by the properties of the adsorbent and pre-calibrated experimentally; among which, the adsorbed amount The adsorption process is exothermic, resulting in a local temperature rise. The temperature rise coefficient is approximately proportional to the adsorption amount, determined by a pre-calibrated unit adsorption amount. , can be defined as: Alternatively, for any micro-element within the bed, based on the concentration difference between its upstream and downstream monitoring points... Given the waste gas flow rate through the micro-element, calculate the adsorption capacity of the micro-element per unit time, and integrate over time to obtain the cumulative adsorption capacity. Furthermore, the bed state sensing layer measures the data in real time. and Based on preset adsorbent parameters, the initial value of local adsorption load saturation at each sensor measuring point is calculated online. .

[0026] Furthermore, the core step in generating the adsorption load distribution map is spatial interpolation, whose input is the initial value of the local adsorption load saturation at discrete points. The data processing unit calculates the real-time position of each sensor measurement point in the bed state sensing network. Values; in these discrete Values ​​and their three-dimensional spatial coordinates As input, the Kriging space interpolation algorithm is used to optimally estimate any unmeasured location within the bed layer, i.e., unbiased and with minimal variance. saturation value By performing dense grid estimation on the entire bed space, a continuous three-dimensional saturation scalar field covering the entire bed region is obtained. The adsorption load distribution is visualized as an adsorption load distribution map with color depth representing the degree of saturation.

[0027] It should be noted that the breakthrough front prediction model is a mechanistic model based on the mass transfer kinetics of the adsorption process, preferably using the extended Yoon-Nelson model or the Thomas model considering axial dispersion; in this embodiment, the Yoon-Nelson model is used to describe the basic form of the fixed-bed adsorption breakthrough curve: ,in, Represented as The bed outlet concentration at any given time, Indicated as import concentration, Expressed as a rate constant, This represents the time required for 50% adsorbate penetration; in the online prediction of this invention, the model is dynamic, and the model parameters... and Instead of being a fixed value, it adaptively adjusts based on the real-time updated bed status: Compared with the average saturation of the current bed layer It is related to the steepness of the adsorption front, and is obtained through real-time data fitting. It is related to the inlet flow rate, concentration, and bed temperature field.

[0028] Furthermore, in the context of the present and historical moments , , , Using these parameters as input, the model parameters are updated in real time through recursive least squares method, thereby enabling rolling predictions of any future time. export concentration When predicted Reaching the preset breakthrough threshold At that time, the corresponding This refers to the predicted breakout time. Meanwhile, the adsorption front morphology equation embedded in the model can simultaneously output the predicted position and shape curve of the front.

[0029] In this embodiment, the real-time adsorption rate in the quantitative information characterizing the state of the key region is calculated by measuring the local saturation. The rate of change over time, dS / dt, is obtained; the temperature correction factor is... The adsorption isotherms of the adsorbent were measured at different constant temperatures, and then fitted. and The temperature rise coefficient is obtained from the relational function. Through small-scale adsorption experiments, the adiabatic temperature rise caused by the complete adsorption of a specific VOC by a unit mass of adsorbent was accurately measured, and the rate constant was calibrated in conjunction with the heat of adsorption of that VOC; The model parameters were obtained by collecting complete adsorption-breakthrough curve data from the system's historical operation and using a nonlinear fitting method to identify the parameters of the model equation.

[0030] The dynamic partitioning control module is used to dynamically divide the adsorption bed into at least one deep saturated adsorption zone and one high-efficiency adsorption zone based on the first processing dataset, and to perform pulsed high-temperature desorption on the deep saturated adsorption zone to obtain a second processing dataset characterizing the state of each partition.

[0031] Specifically, the dynamic partition control module includes at least a partition control first unit, a partition control second unit, and a partition control third unit; wherein, the partition control first unit is configured to dynamically divide the adsorption bed into a deep saturated adsorption zone and a high-efficiency adsorption zone based on the first processing dataset by airflow guidance, and output partition status information to the partition control second unit and the global optimization control module; the partition control second unit is configured to respond to a desorption start command from the partition control first unit and, using the heat recovered from the partition control third unit, perform reverse pulse desorption on the deep saturated adsorption zone, and output the resulting desorption product to the partition control third unit; the partition control third unit is configured to recover the high-grade heat of the desorption product and feed it back to the partition control second unit, condense and recover the organic solvent, and return the generated low-grade tail gas to the inlet of the partition control first unit.

[0032] In one possible implementation, the execution component of the first unit of the zone control is an airflow guiding valve array. The airflow guiding valve array is installed between the main air inlet distribution pipe of the adsorption bed and the air inlet at the top of the bed, and between the air outlet at the bottom of the bed and the subsequent process pipeline, thereby having the ability to independently guide the airflow entering and leaving the bed. After receiving the adsorption load distribution map from the process sensing module, the airflow guiding valve array performs dynamic zoning by dynamically adjusting the opening and closing state of each control valve: closing or reducing the opening of the air inlet valve pointing to the deep saturated adsorption zone, while guiding the main path of the high-concentration incoming gas to the air inlet corresponding to the fine adsorption zone; the valve array on the outlet side is synchronized and coordinated to ensure the independence and integrity of the airflow path of each zone.

[0033] In this embodiment, on the intake side, the airflow guiding valve array consists of a set of high-speed solenoid valves or pneumatic butterfly valves with independently programmable control of their opening. Each valve corresponds to an independent intake branch pipe or distribution grid area at the top of the bed. On the outlet side, a similarly structured valve array is provided to independently collect and guide the outlet airflow of each area.

[0034] Furthermore, the workflow of the dynamic partitioning includes: based on each location in the map... saturation value Apply the preset partitioning rules: All continuous regions are classified as deep saturated adsorption regions, and their spatial coordinate boundaries are defined. It has been decided, among which, This is represented as the depth saturation threshold; The area is classified as the precision adsorption zone, among which, This is represented as the lower limit threshold for determining efficient adsorption. Based on the spatial coordinate boundary of the deep saturated adsorption zone, it is mapped to the corresponding number of one or more inlet / outlet control valves, generating a zone control command containing a list of closed valves and a list of open valves. After executing the zone control command, the high-concentration waste gas is forcibly guided to the inlet with a large valve opening corresponding to the efficient adsorption zone and enters the bed. After flowing through this area, it is discharged from the corresponding outlet valve. At the same time, the inlet and outlet valves corresponding to the deep saturated zone are closed or severely throttled, causing the internal airflow to basically stagnate. Thus, through the redistribution of the global airflow by the external valve array, two functional zones with physically isolated airflow paths and different adsorption tasks are formed within a single fixed bed.

[0035] In this embodiment, the Defined as , Defined as The zone control commands include, but are not limited to: closing all intake valves. and exhaust valve ,in The physical location falls within the coordinate range of the deep saturated adsorption zone; maintain or increase the opening of all valves serving the fine adsorption zone.

[0036] It should be noted that after the dynamic partitioning is completed, the built-in sensor network acquires real-time data on pressure, temperature rise, and concentration in each partition, and calculates the average saturation of each partition. and pressure drop Together, they constitute the partition status information and serve as a key component of the second processed dataset; simultaneously, when Continuously reaching the desorption threshold and Once it is confirmed that the zone is in a low-flow state, a desorption start command is sent to the second zone control unit.

[0037] In one possible implementation, the second partition control unit is used to perform: primary preheating of the desorption fresh air using heat recovered from the third partition control unit; activating the heater to generate pulsed high-temperature hot air in the opposite direction to the adsorption airflow, and precisely guiding it to the deep saturated adsorption zone defined by the first partition control unit for desorption; the pulsed high-temperature desorption performed on the deep saturated adsorption zone has the flow direction of the desorption hot air opposite to the airflow direction of the adsorption stage.

[0038] Specifically, the initiation of pulsed high-temperature desorption strictly depends on the desorption initiation command of the first zone control unit. By using an on-demand desorption mode, rather than the traditional fixed-time-cycle desorption, the ineffective waste of energy or the risk of penetration caused by untimely desorption is avoided. The desorption fresh air first flows through the high-efficiency heat exchanger of the third zone control unit to recover the high-grade sensible heat in the desorption products and complete the first-stage preheating. Then it enters a heater, whose heating strategy is to use medium-grade waste heat from other parts. In this embodiment, the waste heat includes, but is not limited to, the waste heat of condenser cooling water or low-grade tail gas. The bed is preheated in a general and gentle manner through a secondary heat exchanger, so that the bed temperature rises uniformly to the preheating desorption temperature of the adsorbent. Furthermore, the heater rapidly increases the hot air temperature to the high-temperature desorption set value. This high-temperature hot air is injected into the locked deep saturated adsorption zone in a pulse form from the original outlet side to the original inlet side along a path opposite to the adsorption airflow direction. This generates high-temperature, high-concentration VOCs desorption product gas, which is then transported to the third zone control unit for processing.

[0039] It should be noted that the medium-grade waste heat mainly refers to two stable sources: the cooling water circuit of the condenser in the third unit of the zone control system; during the condensation of VOCs, the cooling water is heated, and the outlet water temperature can usually reach 40℃ to 60℃, constituting a stable and usable medium-grade heat source; the low-grade tail gas output from the third unit of the zone control system, whose temperature can still be maintained at 25℃ to 40℃ after condensation; the secondary heat exchanger is specifically a plate heat exchanger or a shell-and-tube heat exchanger. Before entering the main heater, the desorbed fresh air flows through this heat exchanger and interacts with the aforementioned medium-grade waste heat source. Countercurrent heat exchange allows preheating to 50°C to 70°C, recovering heat that would otherwise be dissipated into the environment and significantly reducing the external energy input required to heat the fresh air to the preheating desorption temperature. The preheating desorption temperature refers to the target temperature to which the bed is uniformly preheated using low-to-medium grade waste heat. For zeolite molecular sieve adsorbents treating common VOCs, this temperature is typically set between 80°C and 120°C. The main purpose is to remove physically adsorbed water, reduce the sensible heat required for subsequent heating of the adsorbent, and initially activate the adsorption sites. The high-temperature desorption setpoint refers to the temperature reached by the pulsed hot air. The maximum temperature must be set to ensure rapid and complete desorption of VOCs. For zeolite adsorbents, this temperature is typically set between 180°C and 220°C, with the specific target value determined online by the global optimization control module based on the type and concentration of the target VOCs and the desired desorption rate. The pulsed form refers to the injection of desorption hot air into the deep saturated adsorption zone at a periodically varying high flow rate. In a typical cycle of this embodiment, there is a high-energy pulse segment and a sustaining segment, achieved by a fan in conjunction with a fast regulating valve or frequency converter: a high-energy pulse lasting 10-30 seconds... In the high-energy pulse phase, the hot air flow rate instantly increases to 1.5 to 2.5 times the design maximum flow rate; in the maintenance phase lasting 30 to 90 seconds, the flow rate returns to the basic design flow rate; the total duration of the high-energy pulse phase and the maintenance phase is usually between 45 seconds and 2 minutes, and the specific duration is dynamically adjusted by the global optimization control module according to the desorption kinetic characteristics of the target VOCs and the heat capacity of the bed; the periodic impact creates stronger turbulence and instantaneous pressure difference, which can more effectively disrupt the adsorption equilibrium and purge VOCs from the pores. Compared with constant flow desorption, the desorption rate can be increased by more than 15% under the same total energy consumption.

[0040] In this embodiment, to achieve the reverse flow of hot air from the original outlet side to the original inlet side and to strictly limit it spatially to the deep saturated adsorption zone, this unit is equipped with a desorption path switching valve group. The valve group is usually composed of a series of pneumatically or electrically driven three-way valves or two-way valves, which are installed on the inlet and outlet pipelines leading to the target area. The specific execution process is as follows: When the desorption start command is received, it is confirmed that the first unit of the zone control has closed the original adsorption inlet valve and outlet valve of the deep saturated adsorption zone, or set them to the minimum opening, to complete the airflow isolation. The desorption path switching valve group operates by opening the valve connecting the desorption hot air main pipe and the original outlet pipeline, and simultaneously opening the valve connecting the original inlet pipeline and the desorption product output pipeline, ensuring that the heat and carrier gas are used efficiently and centrally for the regeneration of the target area.

[0041] In one possible implementation, the third zone control unit includes a high-efficiency heat exchanger, a condensation recovery device, and a tail gas circulation pipeline; the high-efficiency heat exchanger is configured to recover high-grade heat from the desorption product gas to preheat the desorption fresh air entering the second zone control unit; the condensation recovery device is configured to condense and separate the organic solvent in the desorption product gas after heat exchange and cooling; the tail gas circulation pipeline is configured to guide the condensed low-grade tail gas back to the inlet of the adsorption bed for preheating the waste gas to be treated or forming a protective gas curtain.

[0042] Specifically, the high-efficiency heat exchanger performs counter-current heat exchange between the high-temperature desorption product gas from the second zone control unit and the desorption fresh air about to enter the second zone control unit, significantly reducing its own temperature while preheating the fresh air to a higher temperature. The high-grade heat recovered is directly reused in the desorption process, greatly reducing the energy consumption load of the subsequent heater, forming the core internal energy cycle. The condensation recovery device condenses the cooled desorption gas into liquid, and separates the organic solvent from the non-condensable gas in the gas-liquid separator. The liquid solvent is recovered to the storage tank, realizing resource recovery. The tail gas circulation pipeline refers to the gas discharged after condensation as low-grade tail gas, which is led back to the front end of the adsorption bed through the pipeline, and then performs the following: mixing with the ambient temperature or low temperature waste gas to be treated, preheating it, and increasing the temperature of the waste gas entering the adsorption bed, which is beneficial to maintaining adsorption performance in cold environments or reducing waste gas heating energy consumption. Optionally, this part of clean and mild gas forms an air curtain at the edge of the bed inlet distributor, which helps to improve the inlet distribution and reduce the wall flow effect.

[0043] In this embodiment, the high-efficiency heat exchanger can cool the desorption product gas, which is approximately 180-220℃, to 70-90℃, while preheating the desorption fresh air from ambient temperature to 100-140℃, with a heat recovery efficiency of not less than 65%. The condensation recovery device includes a water condenser and a chilled brine condenser connected in series, which finally cools the gas to 0-5℃. Subsequently, gas-liquid separation is achieved through a high-efficiency wire mesh demister, and the organic matter concentration in the condensed and recovered liquid solvent is greater than 95%. The exhaust gas circulation pipeline is equipped with an electric three-way regulating valve at the main inlet pipe, which can proportionally distribute the low-grade exhaust gas to: one path is connected to the main exhaust gas pipeline for mixing and preheating; the other path is connected to an annular distribution pipe surrounding the bed inlet, forming a protective air curtain through small nozzles. When the exhaust gas inlet temperature is detected to be below 15℃, the three-way regulating valve switches more than 80% of the low-grade exhaust gas to the preheating pipeline; when the inlet temperature is above 15℃, it is mainly switched to the air curtain pipeline.

[0044] The global optimization control module receives the first processing dataset and the second processing dataset, and outputs a third processing dataset through a global optimization control algorithm. The third processing dataset is used to send control commands to the cooling regeneration module to adjust the adsorption cycle, desorption cycle, partition switching, and fluid parameters.

[0045] Specifically, the global optimization control module is configured to execute the following core process: periodically receive the first processing dataset from the process sensing module and the second processing dataset from the dynamic partition control module, and combine them with preset economic and safety parameters; use a global optimization algorithm based on model predictive control to dynamically optimize and solve the problem while satisfying process constraints, with the goal of minimizing the overall operating cost in the prediction time domain; finally generate and output a third processing dataset; the third processing dataset contains a series of specific, executable control instructions, which are simultaneously issued to the corresponding execution units to coordinate the adjustment of: the opening degree of the intelligent airflow guiding valve array in the dynamic partition control module, the temperature and flow rate of the desorbed hot air; the cooling airflow parameters in the cooling regeneration module; and the operating frequency of other related power equipment, thereby ensuring that the entire system is always in an adaptive optimal operating condition.

[0046] In this embodiment, the global optimization algorithm based on model predictive control includes an internal dynamic prediction model and an optimization solver. The internal dynamic prediction model is used to predict the evolution of the system's key states over a future period, i.e., the prediction time domain, based on the current state and assumed future control commands. These states include, but are not limited to, changes in saturation of each adsorption zone, bed temperature distribution, outlet pollutant concentration, and cumulative energy consumption. The internal dynamic prediction model adopts a gray box model structure, with its core framework based on adsorption mass transfer and heat transfer mechanism equations. Specific kinetic parameters or transfer coefficients in the model are identified and updated online using the first and second processed datasets received in real time. The dynamic optimization solution process uses a sequential quadratic programming algorithm or interior point method to numerically solve the constrained objective function in each control cycle to obtain the optimal control variable sequence.

[0047] It should be noted that the data collected by the global optimization control module includes: data from the process sensing module, including the adsorption load distribution map, the predicted time point output by the penetration front prediction model, and the instantaneous values ​​of the flow rate, concentration, and temperature of the inlet exhaust gas; data from the dynamic zoning control module, including the real-time pressure drop and estimated saturation of each zone fed back from the first zoning control unit, the current temperature, flow rate, duration, and estimated desorption completion of the desorption hot air fed back from the second zoning control unit, the efficiency of the energy recovery heat exchanger, the condensation recovery rate, and the temperature and flow rate of the circulating exhaust gas fed back from the third zoning control unit; and data from the cooling regeneration module, including the temperature and pressure stabilization signals after bed cooling.

[0048] In one possible implementation, within each optimization cycle, a solution is obtained with a comprehensive operating cost. The dynamic optimization function with the objective of minimization is specifically expressed as: ,in, Represented as time Instantaneous energy consumption cost This is expressed as the predicted solvent recovery benefit. This is represented as an instability penalty term, used to quantify the risk caused by uneven bed mass transfer and inefficient desorption control. This represents the time length in which the model predicts the future. Indicates the current time. Expressed as a unit value conversion factor, This is represented as the penalty term weight coefficient.

[0049] It should be noted that the integral term Indicates from the current moment From the beginning, until a predicted point in the future. The total energy cost consumed during the optimization period; in this embodiment, it includes the sum of multiple sub-items, directly related to specific equipment, including but not limited to: electric heating cost, which is related to the real-time power of the heater in the second partition control unit; fan power cost, which is related to the power consumption of the intake fan of the process sensing module, the desorption fan of the second partition control unit, and the cooling fan of the cooling regeneration module, the frequency and flow of which are directly adjusted by the optimization command; refrigeration cost, which is related to the power consumption of the condenser in the third partition control unit, used to realize solvent recovery; revenue item. This means that minimizing the objective function J is actually maximizing the solvent recovery benefit; penalty term Mathematical penalties are applied to adverse conditions that may lead to performance degradation, equipment damage, or control failure during operation, guiding the optimization algorithm to automatically avoid these areas.

[0050] In one possible implementation, the instability penalty term This can be specifically expressed as: , in, This is expressed as the adsorption bed saturation. Variance in space measures the degree of unevenness. The larger the variance, the more severe the oversaturation of some areas and the underutilization of others within the bed, i.e., the higher the unevenness. This is expressed as the predicted exhaust gas outlet concentration. This is expressed as the pollutant emission concentration threshold. and These represent the highest and optimal temperatures of the bed, respectively. , , These represent the severity of penalties for the three unstable factors: inhomogeneity, penetration risk, and temperature deviation.

[0051] Furthermore, the constraints for solving the dynamic optimization function include, but are not limited to, valve opening degree, maximum heater power, maximum fan air volume and frequency limits, maximum bed and pipeline temperature; the outlet pollutant concentration must be continuously lower than the environmental emission standards; the saturation of the efficient adsorption zone must be maintained within a certain range to ensure buffering capacity; the desorption completion rate must reach the set value before it can be stopped; the corresponding area cannot switch back to adsorption before cooling and regeneration are completed; and the desorption start-up must meet the zone saturation triggering conditions.

[0052] The cooling and regeneration module is used to cool and purge the desorbed adsorption bed region in response to the desorption completion signal of the dynamic partition control module and the control command of the global optimization control module, and to feed back the bed ready signal to the global optimization control module.

[0053] Specifically, the activation of the cooling regeneration module is directly triggered by the desorption completion signal issued by the dynamic partition control module. This signal is generated when the pulse desorption program reaches the preset completion conditions, which include the concentration of organic matter in the desorption outlet gas dropping to a set threshold and / or the bed temperature reaching a set value. At the same time, the global optimization control module will send a cooling regeneration parameter instruction package to this module. The cooling regeneration parameter instruction package is based on the global state of the system and specifies the target temperature, recommended cooling gas flow range, and maximum allowable time for this cooling.

[0054] It should be noted that the cooling regeneration module, through control valves and fans, introduces the clean airflow to purge the bed according to the cooling regeneration parameter instruction package; the cooling regeneration module performs purging by monitoring the bed temperature and pressure, and when the average bed temperature drops to the optimal adsorption temperature range and the bed pressure drop returns to stability, it determines that the state reset is complete and generates the bed ready signal; the clean airflow used for cooling purging is preferentially taken from the low-temperature exhaust gas generated after condensation and recovery inside the system, but can also be switched to filtered ambient air; the airflow direction of the cooling purging is the same as the direction of the desorption hot air.

[0055] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other. In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A zeolite adsorption-desorption integrated treatment system, characterized in that, include: Process sensing module: used to acquire the state of the adsorption bed in real time and generate a first processing dataset characterizing the adsorption load distribution and penetration front; Dynamic partitioning control module: Based on the first processing dataset, the adsorption bed is dynamically divided into at least one deep saturated adsorption zone and one high-efficiency adsorption zone, and pulsed high-temperature desorption is performed on the deep saturated adsorption zone to obtain a second processing dataset characterizing the state of each partition. Global optimization control module: used to receive the first processing dataset and the second processing dataset, and output a third processing dataset through a global optimization control algorithm. The third processing dataset is used to send control commands to the cooling regeneration module to adjust the adsorption cycle, desorption cycle, partition switching and fluid parameters. Cooling and regeneration module: In response to the desorption completion signal from the dynamic partition control module and the control command from the global optimization control module, the module cools and purges the desorbed adsorption bed region and feeds back the bed ready signal to the global optimization control module.

2. The zeolite adsorption-desorption integrated treatment system according to claim 1, characterized in that: The process-aware module, in its first processed dataset, includes at least: The adsorption load distribution map, which characterizes the adsorption state distribution, is output in the form of structured data containing the boundary coordinates of the partitions and the quantified saturation values ​​of each region. It is used to quantify the local adsorption load saturation at different locations inside the bed. The frontier prediction information characterizing the dynamic evolution of the process includes at least the predicted time point when the bed outlet concentration reaches the preset breakthrough threshold, as well as the movement speed of the adsorption front and the frontier prediction curve. Quantitative information characterizing the state of key regions includes at least the average saturation value and the real-time adsorption rate.

3. The zeolite adsorption-desorption integrated treatment system according to claim 1, characterized in that: The dynamic partition control module includes at least a partition control first unit, a partition control second unit, and a partition control third unit; The partition control first unit is configured to dynamically divide the adsorption bed into a deep saturation adsorption zone and a fine adsorption zone based on the first processed dataset by airflow guidance, and output the partition status information to the partition control second unit and the global optimization control module. The second partition control unit is configured to respond to a desorption start command from the first partition control unit and use the heat recovered from the third partition control unit to perform reverse pulse desorption on the deep saturated adsorption zone, and output the desorption products to the third partition control unit. The third partition control unit is configured to recover the high-grade heat of the desorption products and feed it back to the second partition control unit, condense and recover the organic solvent, and send the generated low-grade tail gas back to the inlet of the first partition control unit.

4. The zeolite adsorption-desorption integrated treatment system according to claim 3, characterized in that: The dynamic partitioning control module, in its first partitioning control unit, dynamically divides the adsorption bed into at least one deep saturated adsorption zone and one high-efficiency adsorption zone, specifically including: Based on each location in the adsorption load distribution map of the first processed dataset saturation value Apply the preset partitioning rules: Will All continuous regions are classified as deep saturated adsorption regions, and their spatial coordinate boundaries are defined. It has been decided, among which, This is represented as the depth saturation determination threshold; Will The area is classified as the precision adsorption zone, among which, This is expressed as the lower limit threshold for determining precise adsorption. Based on the spatial coordinate boundary of the deep saturated adsorption zone, the corresponding numbers of one or more intake or exhaust control valves are mapped to generate a zone control command containing a list of shut-off valves and a list of open valves.

5. The zeolite adsorption-desorption integrated treatment system according to claim 3, characterized in that: The dynamic partition control module, specifically the second partition control unit, is used to execute: The heat recovered from the third unit of the partition control is used to preheat the desorbed fresh air in the first stage; The heater is activated to generate pulsed high-temperature hot air in the opposite direction to the adsorption airflow, and precisely guided to the deep saturated adsorption zone defined by the first zone control unit for desorption. The pulsed high-temperature desorption performed on the deep saturated adsorption zone has a desorption hot air flow direction opposite to the airflow direction during the adsorption stage.

6. The zeolite adsorption-desorption integrated treatment system according to claim 3, characterized in that: The dynamic zoning control module, the third zoning control unit includes a high-efficiency heat exchanger, a condensation recovery device and an exhaust gas circulation pipeline; The high-efficiency heat exchanger is configured to recover high-grade heat from the desorption product gas to preheat the desorption fresh air entering the second unit of the zone control. The condensation and recovery device is configured to condense and separate the organic solvent in the desorption product gas after heat exchange and cooling. The exhaust gas recirculation pipeline is configured to guide the condensed low-grade exhaust gas back to the inlet of the adsorption bed for preheating the waste gas to be treated or forming a protective gas curtain.

7. The zeolite adsorption-desorption integrated treatment system according to claim 1, characterized in that: The global optimization control module, in each optimization cycle, solves a solution based on the overall operating cost. The dynamic optimization function with the objective of minimization is specifically expressed as: ,in, Represented as time Instantaneous energy consumption cost This is expressed as the predicted solvent recovery benefit. This is represented as an unstable penalty term. This represents the time length in which the model predicts the future. Indicates the current time. Expressed as a unit value conversion factor, This is represented as the penalty term weight coefficient.

8. The zeolite adsorption-desorption integrated treatment system according to claim 7, characterized in that: The global optimization control module, the instability penalty term Specifically, it is expressed as: ， in, This is expressed as the adsorption bed saturation. Variance in space, This is expressed as the predicted exhaust gas outlet concentration. This is expressed as the pollutant emission concentration threshold. and These represent the highest and optimal temperatures of the bed, respectively. , , These represent the severity of penalties for the three unstable factors: inhomogeneity, penetration risk, and temperature deviation.

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