Energy-saving and synergistic treatment method for ultra-low emission of VOCs in lost foam steel casting workshop

Abstract

The application discloses an energy-saving and synergistic treatment method for VOCs ultra-low emission in a lost foam steel casting workshop, and constructs a working condition self-adaptive closed-loop treatment system through synergistic processes such as three-stage gradient grading dust removal, layered rotation dynamic adsorption concentration, low-temperature anti-coking directional catalytic oxidation, four-dimensional parameter coupling heat balance energy-saving regulation and control and multi-stage safety interlocking operation and maintenance. By building a quantitative heat balance model, the dynamic adjustment of the heat supplement power under different working conditions is realized, and the residual heat can be self-sustained under high concentration working conditions. The application can cover all the stable, fluctuating and severe limit production conditions in the workshop, and the non-methane total hydrocarbon concentration of the tail gas can be stably controlled within 10 mg / m3, effectively avoiding problems such as catalyst coking and equipment blockage, and has the advantages of stable operation, low energy consumption and strong universality. The application can replace the traditional photolysis oxidation low-efficiency technology and adapt to the long-term ultra-low emission treatment demand of VOCs in the steel casting industry.

Description

Technical Field

[0001] This invention relates to the field of metallurgical casting waste gas treatment technology, specifically a method for ultra-low emission and energy-saving synergistic treatment of VOCs in lost foam casting workshops. Background Technology

[0002] With the continuous upgrading of domestic industrial air pollution prevention and control standards and the increasing intensity of industrial VOCs ultra-low emission control, the Ministry of Ecology and Environment has listed traditional VOCs photolysis (photo-oxidation) and simple combined purification technologies as inefficient technologies to be phased out. The waste gas generated in the lost foam casting and steel casting production processes of metallurgy has significant industry-specific characteristics: the dust load of the waste gas fluctuates greatly instantaneously, the particle size distribution is wide, the VOCs are mainly non-methane total hydrocarbons, and there are also trace amounts of tar macromolecular impurities generated by resin pyrolysis. Moreover, the production lines mostly operate continuously for 24 hours, and the waste gas concentration and dust load vary significantly between day and night. It belongs to the typical multi-disturbance and complex component industrial waste gas.

[0003] Existing conventional VOCs adsorption + catalytic combustion treatment methods are mostly general-purpose fixed process logics, which have obvious technical adaptation defects: the pretreatment dust removal adopts a fixed time sequence and fixed parameter operation mode, which cannot adapt to the instantaneous high dust impact conditions in the foundry industry, and is prone to dust penetration and blockage of adsorption media and coverage of catalytic active sites; the adsorption and desorption adopts a fixed cycle switching mode, without dynamic adjustment according to the real-time concentration of waste gas, resulting in poor uniformity of adsorption media utilization and large desorption residues; the catalytic process lacks targeted anti-coking and low-temperature adaptation logic, and trace tar components can easily lead to catalyst activity decay, resulting in insufficient purification stability under low-temperature and low-concentration conditions; at the same time, traditional processes lack multi-parameter coupled energy-saving control mechanisms, and cannot match waste heat supply and heat consumption according to real-time operating conditions, resulting in high system energy consumption, poor adaptability to operating conditions, and difficulty in meeting ultra-low emission requirements in the long term. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the existing defects and provide a method for the energy-saving and collaborative treatment of VOCs in lost foam casting workshops. Through multi-process dynamic adaptive coupling control, it can accurately adapt to the complex and fluctuating waste gas conditions of casting, achieve long-term stable ultra-low VOCs emissions, reduce system operating energy consumption and maintenance costs, and meet the industry's environmental compliance and energy-saving production requirements.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for synergistic energy-saving treatment of ultra-low VOCs emissions in a lost foam casting steel workshop, comprising the following steps:

[0006] S1: Three-level gradient classification precision dust removal pretreatment: Real-time monitoring of dust concentration at the inlet of lost foam casting steel exhaust gas and system pressure difference, dynamic matching of dust removal work intensity according to dust impact load, sequential execution of gradient purification steps of large particle inertial coarse separation, fine dust electrostatic pre-purification, and precision membrane deep filtration, graded interception of dust of different particle sizes, dynamic adjustment of dust removal cycle and operating parameters of each dust removal stage, controlling the dust concentration of exhaust gas after pretreatment to within 5mg / m³, and preventing dust from entering the downstream VOCs treatment process;

[0007] S2: Layered Rotation Dynamic Adsorption Concentration Control: The VOCs waste gas after dust removal is diverted to multiple independent adsorption treatment channels. A layered rotation adsorption and offline time-sharing desorption control method is adopted. The adsorption medium is fully adsorbed by periodically switching the adsorption contact conditions.

[0008] S3: Low-temperature anti-coking directional catalytic oxidation purification: The high-concentration VOCs mixed gas obtained by desorption is sent to the catalytic oxidation process. The low-temperature anti-coking catalytic reaction process is adopted, and the starting temperature of the catalytic reaction is controlled at 160℃~180℃. The non-methane total hydrocarbon components in the waste gas are oxidized and decomposed, and the trace resin tar macromolecular impurities in the waste gas are simultaneously cracked to maintain the stable progress of the catalytic reaction and control the concentration of non-methane total hydrocarbons in the tail gas to ≤10mg / m³.

[0009] S4: Four-dimensional parametric coupled thermal balance energy-saving control: A four-dimensional coupled thermal balance control model is established, incorporating dust load, real-time VOCs concentration, catalytic reaction temperature, and waste heat recovery efficiency. Based on the model, multi-parameter linkage adaptive control is achieved to match desorption heat demand with system waste heat supply. The formula for the four-dimensional coupled thermal balance model is:

[0010] Q need =α·C VOCs ·K1+β·T cat ·K2-γ·η rec ·K3-δ·S dust ·K4

[0011] Among them, Q need The real-time heating power required by the system is expressed in kW.

[0012] C VOCs The real-time concentration of non-methane total hydrocarbons in the exhaust gas is expressed in mg / m³, with a value range of 50 to 1200.

[0013] T cat The real-time reaction temperature of the catalytic combustion chamber is expressed in °C, with a range of 160–280.

[0014] η rec The real-time efficiency of waste heat recovery is taken as 0.6 to 0.95.

[0015] S dustThe real-time dust load factor is 0.2 when the dust concentration is ≤5mg / m³, 0.6 when the dust concentration is 5~40mg / m³, and 1.0 when the dust concentration is ≥40mg / m³.

[0016] α=0.022, β=0.15, γ=18.5, and δ=2.8 are fixed correction coefficients;

[0017] K1=K2=K3=K4=1 are dimension matching constants;

[0018] S5: Multi-level operating condition linkage safety interlock and long-term operation and maintenance: Set up a full-process graded safety interlock control logic, and execute graded early warning, parameter adjustment, operating condition switching and inert medium cooling protective operations for operating conditions such as abnormal dust removal pressure difference, adsorption overheating, catalytic temperature exceeding the limit, and sudden change in VOCs concentration. Based on the operation data, predict the saturation state of the adsorption medium and the trend of catalytic activity decay, and formulate corresponding operation and maintenance strategies to ensure the stable operation of the system.

[0019] As a preferred technical solution of the present invention, in step S1, the working conditions are divided into high, medium and low according to the instantaneous dust load at the inlet. Under the high dust impact condition, the cleaning cycle is shortened by 30% to 50%; under the low load condition, the cleaning cycle is extended to achieve dynamic matching between dust removal parameters and exhaust gas load.

[0020] As a preferred technical solution of the present invention, in step S2, after the adsorption of a single channel is saturated, it is switched to offline desorption mode, while the remaining channels remain in online adsorption state to achieve continuous treatment of waste gas.

[0021] During the desorption stage, a uniform air distribution and temperature control method is adopted to eliminate desorption dead zones.

[0022] As a preferred technical solution of the present invention, in step S2, multiple adsorption channels alternately perform offline desorption, the desorption time of a single channel is dynamically adjusted according to the real-time VOCs adsorption concentration, the desorption hot air temperature is controlled at 100℃~140℃, and a bidirectional uniform air distribution mode is adopted for desorption.

[0023] As a preferred technical solution of the present invention, in step S3, a platinum-cerium-manganese ternary composite catalytic system is used in conjunction with a silicon-aluminum anti-coking modification reaction process to simultaneously complete VOCs oxidation and tar impurity cracking in the low-temperature reaction range, thereby maintaining stable catalytic conversion efficiency.

[0024] As a preferred embodiment of the present invention, the control logic of the four-dimensional coupled thermal equilibrium control model in step S4 is as follows:

[0025] Real-time calculation of supplementary heating power Q need Q need When the temperature is ≤0, the external electric auxiliary heating is cut off, and desorption is completed by relying on the waste heat of the flue gas;

[0026] Q need When the value is greater than 0, the output power of the electric auxiliary heating and the distribution ratio of the waste heat are adjusted according to the real-time calculated power gradient to match the real-time operating heat demand.

[0027] As a preferred technical solution of the present invention, the multi-level safety interlocking logic in step S5 includes: dust removal with overpressure differential to enhance ash removal, adsorption unit overheating to cut off desorption hot air and introduce inert medium to cool down, and cutting off air intake and opening cold air dilution when the catalytic furnace overheats or the concentration rises sharply.

[0028] As a preferred technical solution of the present invention, in step S5, the adsorption medium saturation curve and the catalyst activity decay curve are fitted based on cloud-based running data, and the medium replacement, catalyst regeneration and equipment maintenance operations are performed according to the prediction results.

[0029] Compared with the prior art, the beneficial effects of the present invention are: (1) The present invention adopts the dust load gradient adaptive dust removal control process, which can adaptively adjust the dust removal parameters according to the dynamic dust load on site, adapt to the instantaneous high dust impact condition of lost foam casting steel, avoid dust interference with the back-end treatment process, and improve the system operation stability; (2) The multi-channel rotating adsorption and offline time-sharing desorption process can realize uninterrupted continuous treatment of waste gas. By dynamically switching the adsorption working condition and the uniform air distribution desorption mode, the utilization rate of the adsorption medium is optimized, the desorption residue is eliminated, and it is adapted to the continuous production working condition; (3) The low temperature anti-coking coupled catalytic process can realize the simultaneous cracking of VOCs oxidation and tar impurities under low temperature conditions, inhibit catalyst coking and deactivation, and improve the purification stability of complex component waste gas. (4) Construct a four-dimensional parameter coupled thermal balance quantitative control model, which can adaptively match the supplementary heating power and waste heat distribution according to the real-time working conditions, realize self-sustaining operation under high concentration conditions and precise supplementary heating under low concentration conditions, and effectively reduce the energy consumption of system operation; (5) Set up multi-level safety interlocks and data-based operation and maintenance logic for the entire process, which can adapt to the working condition fluctuation scenario, realize graded protection of abnormal working conditions and equipment status prediction, and ensure long-term stable operation of the system. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the governance process of this invention. Detailed Implementation

[0031] 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.

[0032] Example 1: Treatment of high-concentration, low-dust steady-state operating conditions (normal full-capacity production conditions)

[0033] like Figure 1 This embodiment is applied to the full-capacity steady-state production stage of the lost foam casting workshop of a metallurgical steel casting enterprise. The exhaust gas operating parameters are: non-methane total hydrocarbon concentration of exhaust gas 850~980mg / m³, inlet dust concentration 3~5mg / m³, exhaust gas temperature 25~35℃, production line running continuously for 24 hours, and exhaust gas components containing trace amounts of resin cracking tar impurities.

[0034] The specific steps of the treatment method of the present invention are as follows:

[0035] S1: Three-stage gradient dust removal pretreatment: The system monitors the inlet dust concentration and system pressure difference in real time. The current dust concentration is ≤5mg / m³, which is judged as a low dust load condition. The system adopts conventional dust removal cycle operation to sequentially complete the inertial coarse separation of large particles, electrostatic pre-purification of fine dust, and membrane deep filtration. After pretreatment, the dust concentration of the exhaust gas is stably controlled at 4.2mg / m³, which meets the access conditions for downstream treatment.

[0036] S2: Layered Rotational Dynamic Adsorption Concentration: After dust removal, the exhaust gas is evenly distributed to four independent adsorption channels. The system periodically switches the contact conditions of the adsorption medium to achieve full-domain adsorption of the medium.

[0037] The adsorption saturation state is dynamically determined based on the real-time VOCs concentration. Once a single channel is saturated, it automatically switches to offline desorption mode, while the other three channels continue to adsorb online without any production shutdown.

[0038] During the desorption stage, the hot air temperature is controlled at 120℃, and a uniform air distribution mode is adopted in both the upper and lower directions to eliminate desorption dead zones.

[0039] S3: Low-temperature anti-coking catalytic oxidation: The high-concentration VOCs mixture generated by desorption is sent into the catalytic process. The starting temperature of the catalytic reaction is controlled at 170℃. A platinum-cerium-manganese ternary composite catalytic system is used in conjunction with a silicon-aluminum anti-coking modification process to simultaneously oxidize and decompose non-methane total hydrocarbons and crack trace amounts of tar macromolecular impurities, maintaining stable operation of the catalytic reaction.

[0040] S4: Four-dimensional coupled thermal balance energy-saving control: Real-time acquisition of operating parameters: C VOCs =920mg / m³, T cat =215℃、η rec =0.92, S dust =0.2, substitute into the model calculation formula

[0041] Q need =α·C VOCs ·K1+β·T cat ·K2-γ·η rec ·K3-δ·S dust ·K4

[0042] Among them, α=0.022, β=0.15, γ=18.5, δ=2.8, K1=K2=K3=K4=1, we get Q need ≤0.

[0043] The system determines that there is excess waste heat, completely cuts off external electric auxiliary heating, and completes the entire process of desorption heating by relying on the waste heat generated by catalytic combustion of flue gas. This enables the system to operate self-sustainingly without external heat supplementation and adaptively matches the current steady-state heat demand.

[0044] S5: Multi-level safety interlocking and intelligent operation and maintenance: The system monitors the operating parameters of each process throughout the entire process, and triggers interlocking actions when there are no abnormal operating conditions.

[0045] The cloud-based system can fit the adsorption medium saturation curve and the catalyst activity decay curve in real time, dynamically predict the equipment operating status, and generate routine maintenance plans.

[0046] The results of this embodiment are as follows: the concentration of non-methane total hydrocarbons in the exhaust gas is stably maintained at 6-8 mg / m³, which meets the ultra-low emission limit requirements. The system has no external heat source throughout the process, resulting in significant energy saving. The adsorption medium is uniformly adsorbed throughout the entire process, with no local premature saturation. The catalyst does not have coking or deactivation problems.

[0047] Example 2: Control of fluctuations in medium-concentration dust (fluctuations in production mold change conditions)

[0048] This embodiment is applied to the fluctuating stage of mold change and process switching in workshop production. The exhaust gas operating parameters are: non-methane total hydrocarbon concentration of exhaust gas 450-600 mg / m³, inlet dust concentration 15-30 mg / m³, frequent fluctuations in operating conditions, and a slight increase in tar impurity content, which belongs to the typical fluctuating production conditions in the workshop.

[0049] The specific steps of the treatment method of the present invention are as follows:

[0050] S1: Three-stage gradient dust removal pretreatment: Real-time monitoring of inlet dust concentration in the range of 5-40mg / m³ indicates a medium dust load condition. The standard dust cleaning cycle is maintained, and dust particles of various sizes are intercepted in a gradient manner to enhance the purification effect of fine dust. After pretreatment, the dust concentration in the exhaust gas is stably controlled within 4.8mg / m³ to avoid dust disturbing downstream processes.

[0051] S2: Layered and alternating dynamic adsorption and concentration: Waste gas is diverted to four adsorption channels. The system dynamically adjusts the desorption time of a single channel according to the real-time fluctuation of VOCs concentration, maintaining a constant temperature of 110℃ and bidirectional air distribution desorption mode; multiple channels alternate offline desorption, ensuring continuous treatment of waste gas throughout the process, and adapting to the characteristics of frequent fluctuations in operating conditions.

[0052] S3: Low-temperature anti-coking catalytic oxidation: The catalytic reaction initiation temperature is controlled at 165℃. Relying on the ternary composite catalytic system and silicon-aluminum anti-coking modification process, VOCs components are continuously oxidized, and the incremental tar impurities under fluctuating conditions are simultaneously cracked to stabilize the catalytic reaction efficiency.

[0053] S4: Four-dimensional coupled thermal balance energy-saving control: Real-time acquisition of operating parameters: C VOCs =520mg / m³, T cat =195℃、η rec =0.85, S dust =0.6, substituting into the model calculation formula, we get Q. need >0.

[0054] The system precisely activates the electric auxiliary heating based on the calculated power gradient, and simultaneously adjusts the waste heat distribution ratio to match the dynamic heat demand under fluctuating operating conditions, thus avoiding problems such as insufficient desorption and decreased purification efficiency caused by temperature fluctuations.

[0055] S5: Multi-level safety interlocking and intelligent operation and maintenance: The system monitors operating condition fluctuation parameters in real time and dynamically adjusts the operating status of each process; the cloud continuously fits the medium attenuation curve and fine-tunes the maintenance cycle based on the fluctuating operating condition data to ensure stable operation of the system under fluctuating operating conditions.

[0056] The results of this embodiment show that under frequent fluctuations in operating conditions, the concentration of non-methane total hydrocarbons in the exhaust gas remains stable at ≤9mg / m³, with no fluctuations exceeding emission standards. The temperature of the catalytic furnace remains stable, with no issues of exceeding temperature limits or uneven desorption. The system demonstrates excellent adaptability to fluctuations in operating conditions.

[0057] Example 3: Treatment of harsh working conditions with low concentration and high dust (low-load, high-dust production conditions)

[0058] This embodiment is applied to the low-load production stage of the workshop and the high dust stage of the molding process. The exhaust gas operating parameters are: non-methane total hydrocarbon concentration of exhaust gas 80-200mg / m³, inlet dust concentration 45-60mg / m³, large instantaneous dust impact load, low VOCs concentration, and low self-generated heat of the system, which belongs to the harsh extreme operating conditions of the workshop.

[0059] The specific steps of the treatment method of the present invention are as follows:

[0060] S1: Three-stage gradient dust removal pretreatment: Real-time monitoring of inlet dust concentration ≥40mg / m³, which is judged as a high dust impact condition, automatically shortens the cleaning cycle of each dust removal unit by 40%, enhances the classification and interception effect of large particles and fine dust, effectively resists instantaneous dust impact, and after pretreatment, the dust concentration of exhaust gas is stably controlled within 4.5mg / m³, completely preventing dust from entering the downstream process.

[0061] S2: Layered Rotational Dynamic Adsorption Concentration: Targeting the characteristics of low-concentration waste gas, the single-channel adsorption time is extended, while still adopting a multi-channel rotational adsorption and offline desorption mode. The desorption hot air temperature is controlled at 105℃, and the air is distributed at a low speed and uniformly. This adapts to low-concentration and high-disturbance operating conditions, ensuring sufficient adsorption and thorough desorption.

[0062] S3: Low-temperature anti-coking catalytic oxidation: Controlling the starting temperature of the catalytic reaction at 180℃ enhances the low-temperature reaction activity. Relying on the anti-coking modification process, it completely breaks down the trace amounts of tar and dust adhering under high dust conditions, maintaining the stable and efficient catalytic reaction.

[0063] S4: Four-dimensional coupled thermal balance energy-saving control: Real-time acquisition of operating parameters: C VOCs =120mg / m³, T cat =175℃、η rec =0.7, S dust =1.0, substituting into the model calculation formula, we get Q. need >0.

[0064] Based on calculations for high dust and low VOCs conditions, the system progressively increases the output power of the electric auxiliary heating, precisely compensates for system heat loss, stabilizes the desorption temperature and catalytic reaction temperature, and avoids purification failure caused by insufficient temperature under low concentration conditions.

[0065] S5: Multi-level safety interlocking and intelligent operation and maintenance: The system keeps high-level interlocking logic enabled throughout the process, monitors dust removal differential pressure, adsorption temperature and catalytic temperature in real time, and automatically strengthens dust removal operations to address the differential pressure exceeding the limit problem that is prone to occur in high dust conditions; the cloud predicts the attenuation trend of adsorption medium and catalyst in advance based on the operating data of harsh conditions, and pushes maintenance warnings in advance.

[0066] The results of this embodiment show that the system operates stably without any abnormalities under harsh extreme conditions of high dust and low concentration. The concentration of non-methane total hydrocarbons in the exhaust gas is ≤10mg / m³, which fully meets the requirements for ultra-low emissions. There are no hidden dangers of blockage, deactivation, or overheating, and the system has extremely strong adaptability to harsh conditions.

[0067] Based on the test results of the above three sets of different working conditions, it can be seen that the method of the present invention can fully cover all production scenarios in the lost foam casting workshop, including full-capacity steady state, process fluctuation, and low-load high dust.

[0068] For steady-state conditions with high concentration and low dust, this invention can achieve self-sustaining operation without external heating by relying on the system's waste heat, reducing operating energy consumption while ensuring stable ultra-low emissions; for fluctuating conditions with medium concentration and medium dust, dynamic parameter adaptive control can effectively offset the treatment disturbances caused by the fluctuations in operating conditions and maintain stable purification parameters.

[0069] For harsh working conditions with low concentration and high dust, gradient-enhanced dust removal, precise heat replenishment and control, and safety interlock protection can solve the industry problem of poor treatment stability under high dust impact and low calorific value conditions.

[0070] All three sets of embodiments can stably control the concentration of non-methane total hydrocarbons in the exhaust gas to within 10 mg / m³, without any abnormal problems such as catalyst coking, local failure of adsorption medium, or equipment blockage throughout the process. This verifies the technical advantages of the process method of the present invention, which has strong adaptability to operating conditions, high operational stability, and excellent energy-saving effect. It can meet the long-term ultra-low emission treatment needs of continuous and fluctuating complex waste gas in the lost foam casting steel industry.

[0071] The parts of the invention not described in detail are prior art. 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 variations 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. A method for synergistic energy-saving treatment of VOCs in a lost foam casting steel workshop with ultra-low emissions, characterized in that: Includes the following steps: S1: Three-level gradient classification precision dust removal pretreatment: Real-time monitoring of dust concentration at the inlet of lost foam casting steel exhaust gas and system pressure difference, dynamic matching of dust removal work intensity according to dust impact load, sequential execution of gradient purification steps of large particle inertial coarse separation, fine dust electrostatic pre-purification, and precision membrane deep filtration, graded interception of dust of different particle sizes, dynamic adjustment of dust removal cycle and operating parameters of each dust removal stage, controlling the dust concentration of exhaust gas after pretreatment to within 5mg / m³, and preventing dust from entering the downstream VOCs treatment process; S2: Layered Rotation Dynamic Adsorption Concentration Control: The VOCs waste gas after dust removal is diverted to multiple independent adsorption treatment channels. A layered rotation adsorption and offline time-sharing desorption control method is adopted. The adsorption medium is fully adsorbed by periodically switching the adsorption contact conditions. S3: Low-temperature anti-coking directional catalytic oxidation purification: The high-concentration VOCs mixed gas obtained by desorption is sent to the catalytic oxidation process. The low-temperature anti-coking catalytic reaction process is adopted, and the starting temperature of the catalytic reaction is controlled at 160℃~180℃. The non-methane total hydrocarbon components in the waste gas are oxidized and decomposed, and the trace resin tar macromolecular impurities in the waste gas are simultaneously cracked to maintain the stable progress of the catalytic reaction and control the concentration of non-methane total hydrocarbons in the tail gas to ≤10mg / m³. S4: Four-dimensional parametric coupled thermal balance energy-saving control: Establish a four-dimensional coupled thermal balance control model that includes dust load, real-time VOCs concentration, catalytic reaction temperature, and waste heat recovery efficiency. Based on the model, realize multi-parameter linkage adaptive control to match desorption heat demand and system waste heat supply. The formula for the four-dimensional coupled thermal equilibrium model is: Q need =α·C VOCs ·K1+β·T cat ·K2-γ·η rec ·K3-δ·S dust ·K4 Among them, Q need The real-time heating power required by the system is expressed in kW. C VOCs The real-time concentration of non-methane total hydrocarbons in the exhaust gas is expressed in mg / m³, with a value range of 50 to 1200. T cat The real-time reaction temperature of the catalytic combustion chamber is expressed in °C, with a range of 160–280. η rec The real-time efficiency of waste heat recovery is taken as 0.6 to 0.

95. S dust The real-time dust load factor is 0.2 when the dust concentration is ≤5mg / m³, 0.6 when the dust concentration is 5~40mg / m³, and 1.0 when the dust concentration is ≥40mg / m³. α=0.022, β=0.15, γ=18.5, and δ=2.8 are fixed correction coefficients; K1=K2=K3=K4=1 are dimension matching constants; S5: Multi-level operating condition linkage safety interlock and long-term operation and maintenance: Set up a full-process graded safety interlock control logic, and execute graded early warning, parameter adjustment, operating condition switching and inert medium cooling protective operations for operating conditions such as abnormal dust removal pressure difference, adsorption overheating, catalytic temperature exceeding the limit, and sudden change in VOCs concentration. Based on the operation data, predict the saturation state of the adsorption medium and the trend of catalytic activity decay, and formulate corresponding operation and maintenance strategies to ensure the stable operation of the system.

2. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting steel workshop according to claim 1, characterized in that: In step S1, the working conditions are divided into high, medium and low based on the instantaneous dust load at the inlet. Under the high dust impact condition, the cleaning cycle is shortened by 30% to 50%; under the low load condition, the cleaning cycle is extended to achieve dynamic matching between dust removal parameters and exhaust gas load.

3. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting steel workshop according to claim 1, characterized in that: In step S2, after a single channel becomes saturated with adsorption, it switches to offline desorption mode, while the remaining channels remain in online adsorption mode to achieve continuous treatment of waste gas. During the desorption stage, a uniform air distribution and temperature control method is adopted to eliminate desorption dead zones.

4. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting steel workshop according to claim 1, characterized in that: In step S2, multiple adsorption channels alternately perform offline desorption. The desorption time of a single channel is dynamically adjusted according to the real-time VOCs adsorption concentration. The desorption hot air temperature is controlled between 100℃ and 140℃, and a uniform air distribution mode is adopted for desorption.

5. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting workshop according to claim 1, characterized in that: In step S3, a platinum-cerium-manganese ternary composite catalytic system is used in conjunction with a silicon-aluminum anti-coking modification reaction process to simultaneously complete VOCs oxidation and tar impurity cracking in the low-temperature reaction range, thereby maintaining stable catalytic conversion efficiency.

6. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting steel workshop according to claim 1, characterized in that: The control logic of the four-dimensional coupled thermal equilibrium control model in step S4 is as follows: Real-time calculation of supplementary heating power Q need Q need When the temperature is ≤0, the external electric auxiliary heating is cut off, and desorption is completed by relying on the waste heat of the flue gas; Q need When the value is greater than 0, the output power of the electric auxiliary heating and the distribution ratio of the waste heat are adjusted according to the real-time calculated power gradient to match the real-time operating heat demand.

7. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting workshop according to claim 1, characterized in that: The multi-level safety interlock logic in step S5 includes: dust removal with enhanced cleaning due to overpressure differential, cutting off desorption hot air and introducing inert medium to cool down when the adsorption unit is overheated, and cutting off the air intake and starting cold air dilution when the catalytic furnace is overheated or the concentration rises sharply.

8. The method for synergistic treatment of VOCs ultra-low emissions and energy conservation in a lost foam casting workshop according to claim 1, characterized in that: In step S5, the adsorption medium saturation curve and the catalyst activity decay curve are fitted based on cloud-based running data, and medium replacement, catalyst regeneration, and equipment maintenance operations are performed according to the prediction results.

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