Energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system

Abstract

This invention belongs to the field of oil refining and industrial energy conservation and environmental protection technology, and discloses an energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system. The system includes: a deodorization tower body, a dual-zone heat recovery component, a tail gas component identification device, a multi-stage temperature-controlled catalytic reactor, a catalyst response injection component, a linkage control system, and a condensation and tail gas purification unit. This invention utilizes a top- and bottom dual-zone counter-current heat exchange loop to efficiently recover and transfer the sensible heat contained in the tail gas and hot oil to the feed vegetable oil, achieving graded preheating of the oil before deodorization and energy feedback of the discharged hot oil. Through optimization of the convective heat exchange path and increase of the heat exchange area, it minimizes fresh steam consumption, effectively controlling the steam load and energy cost of the deodorization tower. Compared with traditional systems, this invention solves the problems of high steam consumption, large heat loss, and uneconomical operation of existing deodorization processes while ensuring deodorization efficiency.

Description

Technical Field

[0001] This invention belongs to the field of oil refining and industrial energy conservation and environmental protection technology, specifically an energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system. Background Technology

[0002] In the refining process of vegetable oils, in order to improve flavor, enhance quality and remove off-odor components, high-temperature steam deodorization treatment is usually required under reduced pressure. This process relies on the countercurrent contact mass transfer between steam and oil, so that low-molecular-weight volatile organic compounds (VOCs) such as aldehydes, thiols and short-chain fatty acids can escape with the steam, thereby achieving odor removal. However, this process generally suffers from problems such as high steam consumption, low heat recovery rate and ineffective treatment of exhaust gas pollution, resulting in significant energy waste and emission risks.

[0003] With the advancement of policies, the industry has put forward higher requirements for the energy conservation, intelligence and environmental protection of deodorization processes. Although some factories have introduced exhaust gas condensation devices or catalytic purification equipment to try to reduce exhaust gas temperature and VOCs concentration, the treatment paths are mostly static or mechanical combinations, lacking dynamic adjustment mechanisms, making it difficult to achieve synergistic optimization of heat recovery and pollution control.

[0004] In addition, existing deodorization systems generally lack the ability to dynamically monitor and coordinate key process parameters such as the rate of change of exhaust gas component concentration and tower heat exchange efficiency, resulting in system response lag and reliance on manual experience for adjustment, which is not conducive to achieving stable and efficient operation. In terms of control path design, most adopt fixed heat exchange and static temperature control modes, which cannot adjust the catalytic temperature zone and catalyst type in real time according to changes in exhaust gas load, thus limiting purification efficiency and energy-saving potential. Summary of the Invention

[0005] The purpose of this invention is to provide an energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system, the system comprising: The main body of the deodorization tower is used to perform high-temperature steam deodorization treatment on vegetable oil at a set vacuum level and temperature to remove odor components such as aldehydes, thiols and short-chain fatty acids. The removal efficiency is based on a process model established by a multi-component mass transfer removal kinetic formula. The dual-zone heat recovery assembly includes a top heat exchange chamber and a bottom heat exchange chamber. The top heat exchange chamber is a spiral structure with a spiral inner tube serving as the vegetable oil feed pipe and an outer chamber serving as the exhaust gas counter-current channel. The bottom heat exchange chamber is located between the hot oil outlet and the exhaust gas path. Together, they form a counter-current heat exchange loop to achieve heat energy exchange between the oil and the exhaust gas before and after deodorization. The heat exchange relationship is determined by the convective heat transfer calculation formula. The exhaust gas component identification device is installed on the exhaust gas emission path of the deodorization tower. It includes an infrared spectral identifier, a data acquisition interface and an exhaust gas identification and processing unit. The processing unit constructs a component identification model based on support vector machine, calculates the concentration and change trend of various VOCs components in real time, and extracts the change rate ΔC / Δt of key pollutants using the first-order concentration change rate calculation formula. The multi-stage temperature-controlled catalytic reactor includes at least two stages of honeycomb ceramic catalytic units arranged in series. Each unit is equipped with an independent electric heating component and different catalyst modules. The catalyst modules include CuO / γ-Al2O3, MnOx-ZrO2, etc., which are adapted to different VOCs reaction temperature zones. The temperature control design is based on the Arrhenius formula for catalytic reaction rate to construct response efficiency models for different temperature zones. The catalyst response injection assembly includes multiple catalyst storage tanks, a variable frequency injection pump, and a distribution channel with proportional valve control. The assembly determines the required catalyst type and injection flow rate based on the ΔC / Δt value output by the identification device using a nonlinear response function formula. The linkage control system includes a controller, a parameter acquisition module, and a closed-loop feedback decision module. The system is based on the ΔC / Δt of key components in the exhaust gas and the change in heat flux density of the tower, and adjusts the flow rate of the top heat exchange oil, the heating power of the reactor, and the catalyst injection rate in a linkage manner. Its control and adjustment logic is driven by the PID controller adjustment function formula to achieve multi-parameter feedback steady-state control. The condensation and exhaust gas purification unit is connected in series at the tail end of the reactor and includes a spray condenser, a cyclone gas-liquid separator and a bipolar plasma purification module. These are used to realize exhaust gas condensate recovery, light component separation and exhaust gas purification emission control, respectively. The gas-liquid separation efficiency is designed and regulated with reference to the cyclone separation efficiency estimation formula to ensure that the non-methane total hydrocarbon content in the exhaust gas is less than 30 mg / m³.

[0007] Preferably, the main body of the deodorization tower includes: (1) The main body of the deodorization tower is equipped with a steam inlet, a vegetable oil inlet and a tail gas exhaust outlet. The working vacuum degree inside the tower is set to 0.3 bar. The steam temperature is 260°C saturated steam. The vegetable oil flows from top to bottom along the tower body and comes into contact with the high-temperature steam flowing in the opposite direction for mass transfer. The steam carries the odor components of aldehydes, thiols and short-chain fatty acids in the oil to evaporate and escape. A hot oil outlet is set at the bottom of the tower body to ensure continuous output of the deodorized oil. No chemical reagents are added to the overall process to ensure the quality and purity of the vegetable oil. (2) In order to improve the controllability and parameter adjustment accuracy of the deodorization process, a process model based on the multi-component mass transfer removal kinetic formula is constructed. The model takes the concentration difference at the gas-liquid interface as the driving term, and combines the liquid film mass transfer coefficient and the steam disturbance velocity to calculate the transfer rate of odor components from the oil phase to the gas phase. The model parameters include the vapor pressure, distribution coefficient and actual operating temperature of aldehyde and thiol components, and serve as the theoretical basis for determining the steam flow rate, tower height and residence time in the tower design. The kinetics of multi-component mass transfer removal are expressed by the following formula:

[0008] In the formula, : Removal flux of the i-th volatile component (mol / m²·s). : Liquid film mass transfer coefficient (m / s) The equilibrium concentration (mol / m³) of this component in the oil phase. Current concentration (mol / m³); Source: Basic formulas of mass transfer kinetics; Technical effect: It is used to describe the rate at which odor components transfer from the oil phase to the gas phase under high-temperature deodorization conditions, and is the basis for designing the steam consumption and tower cross-sectional area.

[0009] Preferably, the dual-zone heat recovery assembly includes: (1) The top heat exchange chamber adopts a spiral structure design with undeodorized vegetable oil in the inner spiral tube and high-temperature tail gas is introduced into the outer chamber to form a stable heat exchange channel. This structure extends the heat exchange path, increases the heat utilization time, achieves uniform preheating of the oil entering the tower, effectively recovers the sensible heat of the tail gas, and reduces the consumption of fresh steam. The heat transfer process between the inner and outer chambers follows the law of convective heat transfer, and the heat flow is driven by the heat exchange area and temperature difference. (2) The bottom heat exchange chamber is set between the hot oil outlet and the exhaust gas channel. By cross-exchanging heat between the deodorized high-temperature hot oil and the exhaust gas to be discharged, the overall thermal efficiency of the system is further improved. The upper and lower heat exchange chambers form a closed countercurrent loop, so that the heat of the hot oil and the exhaust gas is transferred in stages and gradients, ensuring that the temperature difference between the feed oil and the hot oil is controlled within the set range. This part of the heat exchange behavior is supported by the convective heat transfer calculation formula and the recovery rate is controlled by temperature difference. The formula for calculating convective heat transfer is as follows:

[0010] In the formula, Heat exchange power (W), Heat transfer coefficient (W / m²·K) Heat exchange surface area (m²) Temperature difference (K); Source: Fundamentals of Engineering Thermodynamics, adapted for oil / gas heat transfer calculations; Reference book: Heat Transfer, Sun Xunfang edition; Technical benefits: It is used to calculate the heat exchange power between exhaust gas and cold oil, providing a basis for heat load design of heat exchanger tube diameter and spiral pitch.

[0011] Preferably, the exhaust gas component identification device includes: (1) The exhaust gas identification device is fixedly arranged on the exhaust gas emission path of the deodorization tower. The structure includes an infrared spectral identifier, a temperature and flow rate calibration module and a data acquisition interface. The infrared identifier adopts a non-contact scanning method to continuously acquire the spectrum of the exhaust gas within a set wavelength range, and obtain the absorption intensity information of the target volatile organic compounds (VOCs) in the characteristic absorption band. The temperature and pressure calibration module is used to compensate and correct the real-time state parameters of the exhaust gas to ensure the stability of the spectral measurement. The acquisition interface converts the original spectral signal into a digital vector form and transmits it to the back-end identification model unit in real time to realize the data chain closed loop. (2) The exhaust gas identification and processing unit constructs a component identification model based on support vector machine (SVM). The input is the collected multidimensional spectral vector. After training, the model can quickly identify the concentration of aldehydes, thiols and other typical VOCs. The system performs first-order difference processing on the data of continuous time periods and extracts the ΔC / Δt value of the pollutant component based on the first-order concentration change rate calculation formula. This parameter is used for the trigger judgment of the subsequent catalytic response control module, forming a pollution detection and response linkage mechanism. The formula for calculating the first-order concentration change rate is:

[0012] In the formula, Current concentration Concentration at the previous moment, :Time interval; Source: Introduction to Numerical Analysis; Technical effect: It can detect a rapid increase in pollutants and trigger an adjustment in the response level of the catalytic reactor.

[0013] Preferably, the multi-stage temperature-controlled catalytic reactor comprises: (1) The multi-stage catalytic reactor consists of two sets of honeycomb ceramic catalytic units arranged in series. Each unit is equipped with an independent electric heating component and a precision temperature control module. The internal components are filled with different types of metal oxide catalysts, including CuO / γ-Al2O3 and MnOx-ZrO2. This fixed bed structure can ensure that the high-temperature tail gas and the catalyst can fully contact and react. The system sets the target temperature zone required by each stage of the reaction unit according to the characteristics of VOCs components in the deodorized tail gas, so that multiple types of VOCs can achieve thermal decomposition and catalytic conversion under optimal temperature conditions, thereby improving reaction efficiency and tail gas purification level. (2) To ensure that the temperature control settings at each stage in the catalytic reactor are responsive and accurate, the system constructs a reaction efficiency model based on the Arrhenius formula for the catalytic reaction rate. The formula takes the reaction rate constant k as the core parameter, coupled with the pre-exponential factor A, activation energy Ea and reaction temperature T, and derives the optimal conversion temperature of various VOCs. The temperature control system automatically adjusts the heating power according to the optimal temperature setpoint output by the model to achieve precise temperature matching and dynamic control. The Arrhenius expression for the catalytic reaction rate is as follows:

[0014] In the formula, : Reaction rate constant :Pre-factor (empirical constant) Activation energy (J / mol) Gas constant (8.314 J / mol·K) Temperature (K); Source: Atkins Physical Chemistry, Chapter 8.2; Technical benefits: It clarifies the exponential effect of temperature increase on catalytic rate and provides the fundamental kinetic formula for multi-stage temperature control design.

[0015] Preferably, the catalyst-responsive injection assembly includes: (1) The catalyst response injection component consists of multiple independent storage tanks, a variable frequency injection pump and a distribution channel controlled by a proportional valve. Each storage tank is pre-filled with a specific type of liquid catalyst premix, such as CuO / γ-Al2O3 or MnOx-ZrO2. The variable frequency injection pump adjusts the delivery flow according to the system command, and the proportional valve realizes the flow path switching and directional distribution injection of the corresponding catalyst. They are respectively connected to the inlet of different temperature-controlled catalytic units to realize the catalytic injection operation with type separation and precise position, thereby improving the targeting of multi-stage reaction and the control response speed. (2) The system continuously receives the pollutant concentration change rate ΔC / Δt output by the exhaust gas identification module as a control signal and inputs it into the constructed nonlinear concentration response function model. The function takes ΔC / Δt as the independent variable and associates the set catalyst selection logic with the injection flow rate adjustment curve, thereby constructing a coupling relationship between the pollutant change rate and the catalyst injection intensity. The target flow rate and catalyst type output by the response model are converted by the control system into injection pump frequency and proportional valve angle control commands, driving the precise linkage execution of flow rate and injection components in two dimensions. The formula for the nonlinear concentration response function is:

[0016] in,

[0017] In the formula, Pollutant concentration change rate (ppm / s) : Catalyst injection flow rate (L / min) , : Empirical fitting parameters; Source: Fuzzy Control and Response Curve Fitting Control Theory; Technical benefits: It can respond quickly according to the rate of rise of pollutants, thereby improving the interception capability at the front end of the catalytic reactor.

[0018] Preferably, the linkage control system includes: (1) The linkage control system includes a central controller, a parameter acquisition module and a closed-loop feedback decision module. The acquisition module is used to continuously acquire the ΔC / Δt change value of the main VOCs components in the tail gas, the temperature data of the catalytic reaction zone and the heat flux density distribution data in the tower, and transmit them to the controller as dynamic input. The system can simultaneously track the operating status of the oil heat exchange zone, the catalytic zone and the catalyst injection unit, and construct a multi-parameter linkage control path across the temperature field, concentration field and response execution unit to ensure that the unit operates in a coordinated manner under complex conditions. (2) In order to achieve dynamic and stable control of the multivariable coupled system, the system is designed with a control strategy based on the PID controller adjustment function formula. The controller performs proportional, integral and derivative triple feedback adjustment on ΔC / Δt and heat flux density deviation, and outputs control signals to the heat exchange oil flow pump, the catalytic reactor heating power supply and the liquid injection assembly. By adjusting the execution parameters such as frequency, voltage and valve opening, the system response speed and steady-state accuracy are comprehensively optimized to maintain the long-term efficient operation of the device. The formula for the PID controller regulation function is:

[0019] In the formula, : Control output (such as heating power, pump speed). :Target With the present difference, : Proportional, integral, and differential coefficients; Source: Ogata, Modern Control Engineering, core control algorithms in the field of industrial process control; Technical benefits: Upgrading system control from "switching logic" to "continuous feedback control" to achieve stable linkage between flow, temperature, and response.

[0020] Preferably, the condensation and exhaust gas purification unit includes: (1) The condensation and tail gas purification unit is connected in series at the tail end of the catalytic reactor. The tail gas first enters the spray condenser, and is rapidly cooled by the dual action of the spray medium and the heat exchange tube bundle, so that some water vapor and low boiling point volatile components in the tail gas are condensed and precipitated to form condensate, which is then guided and recovered through the bottom liquid outlet. After that, the mixed gas flow enters the cyclone gas-liquid separator, which relies on the high speed rotation to form a centrifugal field, so that the droplets and light components can be efficiently physically separated, the water content of the tail gas is controlled and the separation purity is improved. The structural parameters of the cyclone separator are calculated and determined by the cyclone separation efficiency estimation formula. (2) The exhaust gas after the cyclone separator continues to enter the bipolar plasma purification module, where active particles are generated under high-voltage pulse excitation to oxidize and decompose residual non-methane total hydrocarbons (NMHC) and other trace VOCs, achieving deep purification. When designing the gas-liquid separation unit, the structural parameters and inlet gas velocity are calculated with reference to the cyclone separation efficiency estimation formula to ensure that the separation efficiency is ≥95%. The whole system can stably control the NMHC concentration in the final exhaust gas to below 30mg / m³, meeting the national emission standards. The formula for estimating cyclone separation efficiency is:

[0021] In the formula, Separation efficiency : constant (related to structure) Pipe diameter (m). , Gas density and viscosity, : Swirl path length (m); Source: "Multiphase Fluid Mechanics", used for industrial hydrocyclone design; Technical benefits: It supports a gas-liquid separation efficiency of over 95%, which is an important basis for the design of exhaust gas purification systems to meet standards.

[0022] The beneficial effects of this invention are as follows: 1. This invention constructs a counter-current heat exchange loop with top and bottom dual zones, which efficiently recovers and transfers the sensible heat contained in the exhaust gas and hot oil to the feed vegetable oil, realizing the staged preheating of the oil before deodorization and the energy feedback of the discharged hot oil. By optimizing the convective heat exchange path and increasing the heat exchange area, the consumption of fresh steam is minimized, and the steam load and energy cost of the deodorization tower are effectively controlled. Compared with the traditional system, it solves the problems of high steam consumption, large heat loss and uneconomical operation of the existing deodorization process while ensuring deodorization efficiency, and meets the requirements of green refining and energy-saving transformation.

[0023] 2. This invention introduces an exhaust gas identification unit based on a support vector machine model, combined with real-time acquired infrared spectral data and a ΔC / Δt change rate extraction algorithm, which can quickly identify VOCs concentration fluctuations and major pollution sources. It also drives a multi-stage temperature-controlled catalytic module to perform graded responses. The catalyst temperature zone is designed to match the optimal decomposition temperature for different VOCs. The matching catalyst injection component precisely controls the type and flow rate according to the identification results, dynamically adjusting the reaction path and intensity, thereby achieving closed-loop coupled control of pollutant component identification, control, and purification. This improves purification efficiency and response speed, and solves the problems of existing systems such as purification lag and crude drug injection.

[0024] 3. This invention integrates a linkage control system to collect multi-source parameters such as heat flux density of the deodorization tower, change rate of exhaust pollutants, catalytic reaction status, and heat exchange efficiency. Combined with PID control logic, it forms a closed-loop regulation path driven by ΔC / Δt. The control system can automatically optimize the hot oil flow rate, heating power, and catalyst injection rhythm, dynamically maintaining the system in a stable operating range of energy saving, deodorization, and emission compliance. This closed-loop mechanism breaks through the traditional static control and experience-based adjustment mode of the system, greatly improving the process's adaptive control capability and process repeatability, and providing a systematic solution for the industrial intelligent upgrading of the deodorization section. Attached Figure Description

[0025] Figure 1 This is a flow chart of the waste heat utilization and catalytic deodorization system of the energy-saving and environmentally friendly vegetable oil deodorization tower of the present invention. Detailed Implementation

[0026] 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.

[0027] like Figure 1 As shown in the figure, this embodiment of the invention provides an energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system, which includes: The main body of the deodorization tower is used to deodorize vegetable oil with high-temperature steam at a set vacuum level and temperature to remove odor components such as aldehydes, thiols and short-chain fatty acids. The removal efficiency is based on a process model established by a multi-component mass transfer removal kinetic formula. The dual-zone heat recovery component includes a top heat exchange chamber and a bottom heat exchange chamber. The top heat exchange chamber has a spiral structure with a spiral inner tube serving as the vegetable oil feed pipe and an outer chamber serving as the exhaust gas counter-current channel. The bottom heat exchange chamber is located between the hot oil outlet and the exhaust gas path. Together, they form a counter-current heat exchange loop to achieve heat energy exchange between the oil and the exhaust gas before and after deodorization. The heat exchange relationship is determined by the convective heat transfer calculation formula. The exhaust gas component identification device is installed on the exhaust gas emission path of the deodorization tower. It includes an infrared spectral identifier, a data acquisition interface and an exhaust gas identification and processing unit. The processing unit constructs a component identification model based on support vector machine, calculates the concentration and change trend of various VOCs components in real time, and extracts the change rate ΔC / Δt of key pollutants using the first-order concentration change rate calculation formula. The multi-stage temperature-controlled catalytic reactor includes at least two stages of honeycomb ceramic catalytic units arranged in series. Each unit is equipped with an independent electric heating component and different catalyst modules. The catalyst modules include CuO / γ-Al2O3, MnOx-ZrO2, etc., which are adapted to different VOCs reaction temperature zones. The temperature control design is based on the Arrhenius formula for catalytic reaction rate to construct response efficiency models for different temperature zones. The catalyst response injection assembly includes multiple catalyst storage tanks, a variable frequency injection pump, and a distribution channel with proportional valve control. The assembly determines the required catalyst type and injection flow rate based on the ΔC / Δt value output by the identification device using a nonlinear response function formula. The linkage control system includes a controller, a parameter acquisition module, and a closed-loop feedback decision module. Based on the ΔC / Δt of key components in the exhaust gas and the change in heat flux density of the tower, the system linkage adjusts the flow rate of the top heat exchange oil, the heating power of the reactor, and the catalyst injection rate. Its control and adjustment logic is driven by the PID controller adjustment function formula to achieve multi-parameter feedback steady-state control. The condensation and exhaust gas purification unit is connected in series at the tail end of the reactor and includes a spray condenser, a cyclone gas-liquid separator and a bipolar plasma purification module. These are used to realize exhaust gas condensate recovery, light component separation and exhaust gas purification emission control, respectively. The gas-liquid separation efficiency is designed and controlled with reference to the cyclone separation efficiency estimation formula to ensure that the non-methane total hydrocarbon content in the exhaust gas is less than 30 mg / m³.

[0028]

Example

[0029] During operation, the deodorization tower operates under a negative pressure of 0.30 bar and is supplied with 260°C saturated steam. The vegetable oil comes into countercurrent contact with the steam inside the tower to remove odor components such as aldehydes and thiols. The top and bottom are respectively equipped with spiral sleeve-type and plate-type heat exchange structures to realize the recovery of sensible heat between the exhaust gas and the incoming and outgoing oil. The feed oil temperature is increased to 120°C, saving about 25% of steam consumption. The exhaust gas identification device uses an infrared spectral sensor to monitor the concentration of VOCs such as formaldehyde and methanethiol in real time. The identification and processing unit extracts the ΔC / Δt value of the pollutant components through a support vector machine model and drives the downstream response system. The catalytic reactor consists of a two-stage honeycomb ceramic reaction bed, with the temperature controlled at 220℃ and 290℃ respectively. It is filled with CuO / γ-Al2O3 and MnOx-ZrO2 catalysts. The response injection component automatically adjusts the catalyst injection flow rate according to the ΔC / Δt value, with a control accuracy of ±0.1 L / min. The entire system adopts a PID closed-loop feedback structure for linkage control, which adjusts the heat exchange pump speed, electric heating power and catalyst injection rate to ensure long-term stable operation of the system. After the exhaust gas is treated by spray condensation, cyclone separation and bipolar plasma, the total non-methane hydrocarbons in the emissions are controlled below 30mg / m³, which meets the national environmental protection standards.

[0030] The deodorization tower body consists of a steam inlet, a vegetable oil inlet, and a tail gas outlet. The working vacuum inside the tower is set at 0.3 bar, and the introduced steam is saturated steam at 260°C. The vegetable oil flows downwards along the tower body, contacting and transferring mass with the counter-flowing high-temperature steam. The steam carries odor components such as aldehydes, thiols, and short-chain fatty acids from the oil, causing them to evaporate and escape. A hot oil outlet is located at the bottom of the tower body to ensure continuous output of deodorized oil. The entire process does not add chemical reagents, ensuring the quality and purity of the vegetable oil. To improve the controllability and accuracy of parameter adjustment in the deodorization process, a process model based on a multi-component mass transfer kinetic formula is constructed. This model uses the concentration difference at the gas-liquid interface as the driving term, combining the liquid film mass transfer coefficient and steam disturbance velocity to calculate the transfer rate of odor components from the oil phase to the gas phase. Model parameters include the vapor pressure, distribution coefficient, and actual operating temperature of aldehydes and thiols, serving as the theoretical basis for determining steam flow rate, tower height, and residence time in the tower design.

[0031] The dual-zone heat recovery component refers to the top heat exchange chamber, which adopts a spiral structure design with a sleeve. Undeodorized vegetable oil is introduced into the inner spiral tube, while high-temperature exhaust gas is introduced into the outer chamber in a counter-current flow, forming a stable heat exchange channel. This structure extends the heat exchange path, increases the heat utilization time, achieves uniform preheating of the oil entering the tower, effectively recovers the sensible heat of the exhaust gas, and reduces the consumption of fresh steam. The heat transfer process between the inner and outer chambers follows the law of convective heat transfer, with heat flow driven by heat exchange area and temperature difference. The bottom heat exchange chamber is located between the hot oil outlet and the exhaust gas channel. By cross-exchanging heat between the deodorized high-temperature hot oil and the exhaust gas to be discharged, the overall thermal efficiency of the system is further improved. The upper and lower heat exchange chambers form a closed counter-current loop, enabling graded gradient heat transfer between the hot oil and the exhaust gas, ensuring that the temperature difference between the feed oil and the hot oil is controlled within a set range. This part of the heat exchange behavior is supported by the convective heat transfer calculation formula, and the recovery rate is controlled by temperature difference regulation.

[0032] The exhaust gas component identification device is a device fixedly arranged on the exhaust gas emission path of the deodorization tower. Its structure includes an infrared spectral identifier, a temperature and flow rate calibration module, and a data acquisition interface. The infrared identifier uses a non-contact scanning method to continuously acquire the spectrum of the exhaust gas within a set wavelength range, obtaining the absorption intensity information of the target volatile organic compounds (VOCs) in the characteristic absorption band. The temperature and pressure calibration module is used to compensate and correct the real-time state parameters of the exhaust gas, ensuring the stability of the spectral measurement. The acquisition interface converts the raw spectral signal into a digital vector form and transmits it to the back-end identification model unit in real time, realizing a closed-loop data chain. The exhaust gas identification processing unit constructs a component identification model based on a support vector machine (SVM). The input is the acquired multi-dimensional spectral vector. After training, the model can quickly identify the concentrations of aldehydes, thiols, and other typical VOCs. The system performs first-order difference processing on the continuous time-period data and extracts the ΔC / Δt value of the pollutant component based on the first-order concentration change rate calculation formula. This parameter is used for the trigger judgment of the subsequent catalytic response control module, forming a pollution detection and response linkage mechanism.

[0033] The multi-stage temperature-controlled catalytic reactor refers to a multi-stage catalytic reactor composed of two sets of honeycomb ceramic catalytic units arranged in series. Each unit is equipped with an independent electric heating component and a precision temperature control module, and is filled with different types of metal oxide catalysts, including CuO / γ-Al2O3 and MnOx-ZrO2. This fixed-bed structure ensures sufficient contact and reaction between the high-temperature exhaust gas and the catalyst. Based on the characteristics of VOCs components in the deodorized exhaust gas, the system sets the target temperature zone required for each stage of the reaction unit, enabling various VOCs to achieve thermal decomposition and catalytic conversion under optimal temperature conditions, thereby improving reaction efficiency and exhaust gas purification. To ensure the responsiveness and accuracy of the temperature control settings at each stage in the catalytic reactor, the system constructs a reaction efficiency model based on the Arrhenius equation for the catalytic reaction rate. The equation uses the reaction rate constant k as the core parameter, coupled with the pre-exponential factor A, activation energy Ea, and reaction temperature T, to derive the optimal conversion temperature for various VOCs. The temperature control system automatically adjusts the heating power according to the optimal temperature setpoint output by the model, achieving precise temperature zone matching and dynamic control.

[0034] The catalyst response injection component consists of multiple independent storage tanks, a variable frequency injection pump, and a distribution channel controlled by a proportional valve. Each storage tank is pre-filled with a specific type of liquid catalyst premix, such as CuO / γ-Al2O3 or MnOx-ZrO2. The variable frequency injection pump adjusts the delivery flow rate according to system instructions, and the proportional valve realizes the flow path switching and directional distribution injection of the corresponding catalyst. They are connected to the inlets of different temperature-controlled catalytic units to achieve type separation and precise location of catalytic injection operations, improving the targeting of multi-stage reactions and the speed of control response. The system continuously receives the pollutant concentration change rate ΔC / Δt output by the exhaust gas identification module as a control signal and inputs it into the constructed nonlinear concentration response function model. This function uses ΔC / Δt as the independent variable and associates it with the set catalyst selection logic and injection flow rate adjustment curve, thereby constructing a coupling relationship between the pollutant change rate and the catalytic injection intensity. The target flow rate and catalyst type output by the response model are converted by the control system into injection pump frequency and proportional valve angle control commands, driving precise linkage execution of flow rate and injection components in two dimensions.

[0035] The linkage control system refers to a system comprising a central controller, a parameter acquisition module, and a closed-loop feedback decision module. The acquisition module continuously acquires the ΔC / Δt changes of the main VOCs components in the exhaust gas, temperature data of the catalytic reaction zone, and heat flux density distribution data within the tower, and transmits these as dynamic inputs to the controller. The system can simultaneously track the operating status of the oil heat exchange zone, the catalytic zone, and the catalyst injection unit, constructing a multi-parameter linkage control path across temperature fields, concentration fields, and response execution units to ensure coordinated operation of the unit under complex conditions. To achieve dynamic and stable control of the multivariable coupled system, the system designs a control strategy based on the PID controller adjustment function formula. The controller performs proportional, integral, and derivative triple feedback regulation on ΔC / Δt and heat flux density deviations, outputting control signals to the heat exchange oil flow pump, the catalytic reactor heating power supply, and the liquid injection components. By adjusting execution parameters such as frequency, voltage, and valve opening, the system achieves comprehensive optimization of response speed and steady-state accuracy, maintaining long-term efficient operation of the unit.

[0036] The condensation and exhaust gas purification unit refers to the condensation and exhaust gas purification unit connected in series at the tail end of the catalytic reactor. The exhaust gas first enters the spray-type condenser, where it is rapidly cooled by the combined action of the spray medium and the heat exchange tube bundle. This causes some water vapor and low-boiling-point volatile components in the exhaust gas to condense and precipitate into condensate, which is then guided and recovered through the bottom liquid outlet. The mixed gas flow then enters the cyclone gas-liquid separator, where the high-speed rotation creates a centrifugal field, enabling efficient physical separation of droplets and light components. This controls the water content of the exhaust gas and improves the separation purity. The structural parameters of the cyclone separator are calculated using the cyclone separation efficiency estimation formula. After the cyclone separator, the exhaust gas continues to enter the bipolar plasma purification module, where active particles are generated under high-voltage pulse excitation. These particles oxidize and decompose residual non-methane total hydrocarbons (NMHC) and other trace VOCs, achieving deep purification. The gas-liquid separation unit is designed with reference to the cyclone separation efficiency estimation formula to calculate the structural parameters and inlet gas velocity, ensuring a separation efficiency of ≥95%. The entire system can stably control the NMHC concentration in the final exhaust gas to below 30 mg / m³, meeting national emission standards.

[0037] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system, characterized in that: The system includes: ​ The main body of the deodorization tower includes a deodorization tower with set vacuum and high-temperature steam conditions, which removes odor components such as aldehydes and thiols based on a multi-component mass transfer and removal kinetic model; The dual-zone heat recovery assembly includes a top heat exchange chamber and a bottom heat exchange chamber. The top heat exchange chamber adopts a sleeve-and-spiral structure design. Undeodorized vegetable oil is introduced into the inner spiral tube, while high-temperature exhaust gas is introduced into the outer chamber to flow counter-currently, forming a stable heat exchange channel. The bottom heat exchange chamber is located between the hot oil outlet and the exhaust gas channel. By cross-exchanging heat between the deodorized high-temperature hot oil and the exhaust gas to be discharged, the overall thermal efficiency of the system is further improved. The heat exchange relationship is established by the convective heat transfer calculation formula. An exhaust gas component identification device is installed on the exhaust gas emission path of the main body of the deodorization tower. The exhaust gas component identification device includes an infrared spectral identifier, a temperature and flow rate calibration unit, a data acquisition interface, and an exhaust gas identification and processing unit. The exhaust gas identification and processing unit constructs a component identification model based on support vector machine (SVM). The input is the acquired multidimensional spectral vector. After training, the model can quickly identify the concentrations of aldehydes, thiols, and other typical VOCs. It also performs first-order difference processing on the exhaust gas concentration data over continuous time periods to extract the concentration change rate ΔC / Δt of the pollutant components. The multi-stage temperature-controlled catalytic reactor consists of two sets of honeycomb ceramic catalytic units connected in series. Each unit is equipped with an independent heating component and a dedicated temperature control module. Different types of catalysts, such as CuO / γ-Al2O3 and MnOx-ZrO2, are filled inside the catalytic units. The fixed-bed structure ensures that the gas is in full contact with the catalyst at high temperature. The temperature control strategy is based on the reaction efficiency model constructed by the Arrhenius formula. The catalyst response injection assembly, including a storage tank, a variable frequency pump, and a proportional valve, controls the catalyst type and injection flow rate based on ΔC / Δt and a nonlinear response function. The linkage control system includes a controller and a feedback module. Based on the changes in ΔC / Δt and heat flux density, it uses a PID control function to adjust the operating parameters of each unit in a linkage manner. The condensation and exhaust gas purification unit includes a condenser, a cyclone separator, and a plasma module. The structural design references the cyclone separation efficiency estimation formula and controls exhaust gas emission standards.

2. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The main body of the deodorization tower includes: (1) The main body of the deodorization tower is equipped with a steam inlet, a vegetable oil inlet and a tail gas exhaust outlet. The working vacuum degree inside the tower is set to 0.3 bar. The steam temperature is 260°C saturated steam. The vegetable oil flows from top to bottom along the tower body and comes into contact with the high-temperature steam flowing in the opposite direction for mass transfer. The steam carries the odor components of aldehydes, thiols and short-chain fatty acids in the oil to evaporate and escape. A hot oil outlet is set at the bottom of the tower body to ensure continuous output of the deodorized oil. No chemical reagents are added to the overall process to ensure the quality and purity of the vegetable oil. (2) In order to improve the controllability and parameter adjustment accuracy of the deodorization process, a process model based on the multi-component mass transfer removal kinetic formula is constructed. The model takes the concentration difference at the gas-liquid interface as the driving term, and combines the liquid film mass transfer coefficient and the steam disturbance velocity to calculate the transfer rate of odor components from the oil phase to the gas phase.

3. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The dual-zone heat recovery assembly includes: (1) The heat transfer process between the inner and outer cavities follows the law of convective heat transfer, and the heat flow is driven by the heat transfer area and temperature difference; (2) The upper and lower heat exchange chambers form a closed countercurrent loop, which enables the heat of hot oil and tail gas to be transferred in stages and gradients, ensuring that the temperature difference between the feed oil and the hot oil is controlled within the set range. This is supported by the convective heat transfer calculation formula and the recovery rate is controlled by temperature difference regulation.

4. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The exhaust gas component identification device includes: (1) The infrared detector is used for non-contact scanning of exhaust gas spectral signals to obtain the absorption intensity of target VOCs components in characteristic bands; the matching temperature and pressure compensation unit ensures the stability of the measurement values, and the acquisition interface converts the raw spectral data into a processable digital signal and sends it to the back-end recognition model module. (2) The system performs first-order difference processing on the data of continuous time periods and extracts the ΔC / Δt value of the pollutant component based on the first-order concentration change rate calculation formula. This parameter is used for the trigger judgment of the subsequent catalytic response control module, forming a pollution detection and response linkage mechanism.

5. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The multi-stage temperature-controlled catalytic reactor includes: (1) The system sets different temperature ranges for each stage of the reaction zone according to the different components of the tail gas, so that different VOCs can be efficiently cracked and converted in the corresponding temperature range; (2) To ensure that the temperature control settings at each stage in the catalytic reactor are responsive and accurate, the system constructs a reaction efficiency model based on the Arrhenius formula for the catalytic reaction rate. The formula takes the reaction rate constant k as the core parameter, coupled with the pre-index factor A, activation energy Ea and reaction temperature T, and derives the optimal conversion temperature of various VOCs. The temperature control system automatically adjusts the heating power according to the optimal temperature set value output by the model to achieve precise temperature matching and dynamic control.

6. The energy-saving and environmentally friendly vegetable oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The catalyst-responsive injection component includes: (1) The catalyst response injection component includes multiple independent storage tanks, a variable frequency injection pump and a distribution channel controlled by a proportional valve. CuO / γ-Al2O3 and MnOx-ZrO2 liquid catalyst premixes are pre-stored in different storage tanks. The variable frequency pump is used to control the injection rate. The proportional valve switches channels according to the control command to realize the diversion injection of different types of catalysts at different reactor inlet positions, thereby improving the reaction targeting and response speed. (2) The system receives the ΔC / Δt value output by the exhaust gas identification device in real time and uses it as an input signal to input the nonlinear concentration response function formula. This function uses ΔC / Δt as the independent variable, matches the corresponding catalyst type and flow rate adjustment curve, and realizes the coupled regulation of pollutant change rate and catalytic injection intensity. The regulation result is converted by the control system into injection pump frequency and valve position control commands to realize precise injection of flow rate and components in two dimensions.

7. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The linkage control system includes: (1) The linkage control system includes a central controller, a parameter acquisition module and a closed-loop feedback decision module. The parameter acquisition module monitors the ΔC / Δt change value of key VOCs components in the exhaust gas, the catalyst temperature and the heat flux density distribution in the tower in real time. The acquired data is transmitted to the controller as the basis for control commands. The system can simultaneously track the operating status of the oil preheating zone, the catalytic zone and the injection unit, and construct a dynamic linkage data path between thermal, gas components and catalyst. (2) In order to achieve dynamic and stable control of the multivariable coupled system, the system designs a control strategy based on the PID controller adjustment function formula. The controller performs proportional, integral and derivative triple feedback adjustment on ΔC / Δt and heat flux density deviation, and outputs control signals to the heat exchange oil flow pump, the catalytic reactor heating power supply and the liquid injection component. By adjusting the frequency, voltage and valve opening execution parameters, the system response speed and steady-state accuracy are comprehensively optimized to maintain the long-term efficient operation of the device.

8. The energy-saving and environment-friendly plant oil deodorization tower waste heat utilization and catalytic deodorization system according to claim 1, characterized in that: The condensation and exhaust gas purification unit includes: (1) The condensation and exhaust gas purification unit is installed at the tail end of the multi-stage catalytic reactor, including a spray condenser and a cyclone gas-liquid separator. The high-temperature exhaust gas is first cooled down rapidly by the condenser. Some water vapor and low-boiling-point components in the exhaust gas are condensed into liquid phase and led out through the bottom condensate recovery pipe. After condensation, the mixture enters the cyclone gas-liquid separator, which strengthens the phase separation of droplets and light components by relying on centrifugal force. (2) The exhaust gas after the cyclone separator continues to enter the bipolar plasma purification module, where active particles are generated under high-voltage pulse excitation to oxidize and decompose residual non-methane total hydrocarbons (NMHC) and other trace VOCs, achieving deep purification. When designing the gas-liquid separation unit, the structural parameters and inlet gas velocity are calculated with reference to the cyclone separation efficiency estimation formula to ensure that the separation efficiency is ≥95%. The entire system can stably control the NMHC concentration in the final exhaust gas to below 30 mg / m³, meeting the national emission standards.

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