Device and method for separating and recycling multiple components in rectification tail gas

Abstract

The invention provides a rectification tail gas multi-component separation and recycling device and method, and relates to the technical field of tail gas treatment, the rectification tail gas multi-component separation and recycling device comprises a rectification unit, an emptying collection module, a condensation liquid separation module, a tail gas treatment module, a waste liquid collection module and an intelligent control module; the rectification unit is provided with a diffused gas outlet and an emptying liquid discharge outlet; the emptying collection module is an emptying liquid raising tank, and an inlet of the emptying collection module is communicated with a diffused gas outlet of the rectification unit; the condensation liquid separation module is an emptying condenser, a gas phase inlet of the condensation liquid separation module is communicated with an outlet of the emptying liquid raising tank, a gas phase outlet is connected with the tail gas treatment module, and a liquid phase outlet is connected with the waste liquid collection module; through two-stage treatment of condensation liquid separation and RTO incineration, 80%-90% of condensable components in the diffused gas are firstly removed, RTO treatment load is reduced, and then high-temperature incineration at 800-850 DEG C is performed, so that the removal rate of harmful components is greatly increased, and the latest environment-friendly emission standard is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tail gas treatment, and particularly relates to a device and method for separating and recycling multiple components of rectification tail gas. BACKGROUND

[0002] In the production process of chemical rectification, rectification units such as benzene purification tower and toluene separation tower will synchronously produce two types of pollutants: one is the diffused gas at the top / side of the tower, containing harmful components such as VOCs, light hydrocarbons and hydrogen sulfide, and the other is the vented liquid at the bottom / pipeline, containing recoverable components such as high-sulfur organic matter and residual solvent. The existing treatment technology generally has the problem of disconnection between division and treatment: most devices only design a single incineration treatment process for the diffused gas, such as directly entering an RTO, without first recovering the condensable liquid components in the gas phase through condensation and separation, resulting in waste of liquid resources. At the same time, the vented liquid is usually temporarily stored in an independent tank without being collected together with the condensate of the diffused gas, which is easy to cause secondary leakage due to out-of-control liquid level in the tank, and has a high environmental risk. On the other hand, the existing technology is difficult to balance the dual goals of environmental protection and resource utilization. In the traditional process, the diffused gas is directly introduced into the RTO without condensation, which will cause the combustion temperature of the RTO to be unstable due to the fluctuation of water content and heavy hydrocarbon content in the gas phase, and the removal rate of harmful components can only be maintained at 85%-90%, which is difficult to meet the strict environmental standards. When the vented liquid and the condensate are treated separately, additional pumps and heating equipment need to be invested, which not only increases energy consumption, but also causes the light components in the liquid to volatilize again, forming a treatment-pollution cycle, and cannot realize the synergistic optimization of environmental protection and resource utilization. Therefore, the present application proposes a device and method for separating and recycling multiple components of rectification tail gas to solve the problems in the prior art. SUMMARY

[0003] In view of the above problems, the present application provides a device and method for separating and recycling multiple components of rectification tail gas, which removes 80%-90% of the condensable components in the diffused gas through two-stage treatment of condensation and separation and RTO incineration, reduces the treatment load of the RTO, and greatly improves the removal rate of harmful components through high-temperature incineration at 800-850 DEG C, thereby meeting the latest environmental emission standards.

[0004] To achieve the purpose of the present application, the present application realizes the following technical scheme: a device for separating and recycling multiple components of rectification tail gas, comprising a rectification unit, a vented liquid collection module, a condensation and separation module, a tail gas treatment module, a waste liquid collection module and an intelligent control module; the rectification unit is provided with a diffused gas outlet and a vented liquid outlet; the vented liquid collection module is a vented liquid lifting tank, the inlet of which is communicated with the diffused gas outlet of the rectification unit; the condensation and separation module is a vented condenser, the gas phase inlet of which is communicated with the outlet of the vented liquid lifting tank, the gas phase outlet is connected with the tail gas treatment module, and the liquid phase outlet is connected with the waste liquid collection module. The waste liquid collection module includes a waste liquid tank and a high-sulfur waste liquid tank. The inlet of the waste liquid tank is connected to the liquid phase outlet of the venting condenser and the venting outlet of the distillation unit, respectively. The outlet of the waste liquid tank is connected to the high-sulfur waste liquid tank. The intelligent control module is electrically connected to the venting condenser, the venting condenser, and the waste liquid tank, respectively, and is used to regulate the liquid level and temperature parameters.

[0005] The further improvement lies in that the condensing temperature adjustment range of the venting condenser is 35-55℃, and the condensing pressure adjustment range is 0.2-0.4MPa.

[0006] A further improvement is that the liquid level threshold of the waste liquid tank has an adjustment function, and the adjustment range of the liquid level threshold of the waste liquid tank is 75%-85% of the tank capacity.

[0007] The further improvement lies in the fact that the exhaust gas treatment module is an RTO incinerator with a combustion temperature range of 800-850℃ and a flue gas residence time of 1.8-2.5s.

[0008] A further improvement is that the venting and liquid-lifting tank has a built-in baffle plate to reduce the flow rate of the released gas and reduce droplet entrainment.

[0009] A method for multi-component separation and recovery of distillation tail gas includes the following steps: S1: Gas collection, the gas released from the distillation unit is introduced into the venting and liquid lifting tank for buffering. S2: Condensation and liquid separation treatment. Start the venting condenser to condense and release gas at 35-55℃. Condensable liquid phase is introduced into waste liquid tank, and non-condensable gas phase is introduced into tail gas treatment module. S3: Vent and drain liquid collection, the vent and drain liquid from the distillation unit is directly introduced into the waste liquid tank and mixed with the condensate; S4: Waste liquid is transferred in stages. When the liquid level in the waste liquid tank reaches the preset threshold, the mixed waste liquid is transferred to the high-sulfur waste liquid tank. S5: Exhaust gas terminal treatment. The exhaust gas treatment module incinerates the uncondensed gas phase at 800-850℃, and the gas is discharged after meeting the standards.

[0010] A further improvement is made in S3, where the waste liquid collection rate is calculated using the following formula: θ = (M1 + M2) / M_total × 100% Where: θ is the total collection rate of mixed waste liquid, in %, with a value of ≥93%; M1 is the mass flow rate of condensate from the vented condenser, in kg / h; M2 is the mass flow rate of vented liquid from the distillation unit, in kg / h; M_total is the theoretical total mass flow rate of collectable waste liquid based on distillation material balance, in kg / h.

[0011] Further improvement lies in that in the S4, the mixed waste liquid is transported by a variable frequency conveying pump, and the starting and stopping of the automatic transport of the mixed waste liquid is realized by the following threshold linkage algorithm:

[0012] Further improvement lies in that in the S4, the automatic transport of the mixed waste liquid is triggered and stopped by the following threshold linkage algorithm: , The transport is started when L real ≥ L trigger ; , The transport is stopped when t operation ≥ t stop ; Wherein, t trigger is the pre-judgment time for the liquid level to rise from the initial value to the trigger value, in units of h, for activating the standby state of the variable frequency conveying pump in advance; L real is the real-time liquid level of the waste liquid tank, in units of % tank capacity; L initial is the initial liquid level of the transport cycle, in units of % tank capacity, taking the liquid level value at the time of the last transport stop; v L is the average rising rate of the liquid level, in units of % tank capacity / h, calculated by the change amount of L real in the last 10 minutes, ; L trigger is the transport starting threshold liquid level, in units of % tank capacity, and is pre-set to 75%-85% tank capacity; t stop is the pre-judgment stop time required for a single transport, in units of h, to ensure that the liquid level is reduced to a safe range after transport; L safe is the safe liquid level after transport is stopped, in units of % tank capacity, and is pre-set to 15%-20% tank capacity, with a buffer space reserved; V tank is the effective volume of the waste liquid tank, in units of L; Q pump is the rated conveying flow of the variable frequency conveying pump, in units of L / h; t operation is the actual operation time of the variable frequency conveying pump, in units of h, which is recorded in real time by the intelligent control module.

[0013] Further improvement lies in that in the S5, when the standard is judged, the harmful component removal rate of the tail gas treatment module is calculated by the following formula: η=[(C1-C2) / C1]×100%, Wherein, η is the harmful component removal rate, in units of %, and is ≥ 99%; C1 is the harmful component concentration in the gas phase at the outlet of the vent condenser, in units of mg / m³; C2 is the harmful component concentration in the tail gas at the outlet of the tail gas treatment module, in units of mg / m³.

[0014] The beneficial effects of the present application are: 1. The present application removes 80%-90% of the condensable components in the diffused gas through two-stage treatment of condensation and separation and RTO incineration, reduces the RTO treatment load, and greatly improves the removal rate of harmful components through high-temperature incineration at 800-850 DEG C, thereby meeting the latest environmental protection emission standards.

[0015] 2. The present application cooperatively collects the venting liquid and the condensate of the diffused gas, avoids the waste of condensable liquids in the diffused gas with gas phase incineration, and temporarily stores the mixed waste liquid in the high-sulfur waste liquid tank, so that the high-sulfur components can be recycled as chemical raw materials in the future, and the resource utilization rate is greatly improved compared with the traditional separate treatment process.

[0016] 3, The intelligent control module of the application monitors the liquid level of the venting and liquid lifting tank, the temperature of the venting condenser and the liquid level of the waste liquid tank in real time, avoids the vibration of the equipment caused by airflow impact and the leakage caused by out-of-control liquid level, reduces the fuel consumption of RTO through condensation pretreatment and reduces the operation cost of the system. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a front view of the application; Figure 2 is a flow chart of the application. DETAILED DESCRIPTION

[0018] In order to deepen the understanding of the application, the application will be further described in combination with the embodiments below, and the embodiments are only used to explain the application and do not constitute a limitation on the protection scope of the application. Example 1

[0019] According to Figure 1 , 2 , the present embodiment proposes a multi-component separation and recycling device for rectified tail gas, which comprises a rectification unit, a venting and collecting module, a condensation and separation module, a tail gas treatment module, a waste liquid collecting module and an intelligent control module; the rectification unit is provided with a diffused gas outlet and a venting and liquid discharge outlet; the venting and collecting module is a venting and liquid lifting tank, the inlet of which is communicated with the diffused gas outlet of the rectification unit; the condensation and separation module is a venting condenser, the gas phase inlet of which is communicated with the outlet of the venting and liquid lifting tank, the gas phase outlet of which is connected with the tail gas treatment module, and the liquid phase outlet of which is connected with the waste liquid collecting module; The waste liquid collecting module comprises a waste liquid tank and a high-sulfur waste liquid tank, and the inlet of the waste liquid tank is connected with the liquid phase outlet of the venting condenser and the venting and liquid discharge outlet of the rectification unit in two ways, respectively; the outlet of the waste liquid tank is connected with the high-sulfur waste liquid tank; the intelligent control module is electrically connected with the venting and liquid lifting tank, the venting condenser and the waste liquid tank, respectively, for regulating and controlling the liquid level and temperature parameters. The intelligent control module monitors the liquid level of the venting and liquid lifting tank, the temperature of the venting condenser and the liquid level of the waste liquid tank in real time, avoids the vibration of the equipment caused by airflow impact and the leakage caused by out-of-control liquid level, reduces the fuel consumption of RTO through condensation pretreatment and reduces the operation cost of the system.

[0020] The condensing temperature of the vent condenser is adjustable from 35-55℃, and the condensing pressure is adjustable from 0.2-0.4MPa. The liquid level threshold of the waste liquid tank is adjustable, and the liquid level threshold adjustment range is 75%-85% of the tank capacity. The exhaust gas treatment module is an RTO incinerator with a combustion temperature range of 800-850℃ and a flue gas residence time of 1.8-2.5s. The vent liquid lifting tank has built-in baffles to reduce the flow rate of the vented gas and reduce droplet entrainment. Through two-stage treatment of condensation and liquid separation followed by RTO incineration, 80%-90% of the condensable components in the vented gas are first removed, reducing the RTO treatment load. Then, high-temperature incineration at 800-850℃ greatly improves the removal rate of harmful components, meeting the latest environmental emission standards.

[0021] A method for multi-component separation and recovery of distillation tail gas includes the following steps: S1: Gas collection, the gas released from the distillation unit is introduced into the venting and liquid lifting tank for buffering. S2: Condensation and liquid separation treatment. Start the venting condenser to condense and release gas at 35-55℃. Condensable liquid phase is introduced into waste liquid tank, and non-condensable gas phase is introduced into tail gas treatment module. S3: Vent and Drain Collection: The vent and drain liquid from the distillation unit is directly introduced into the waste liquid tank and mixed with the condensate. The waste liquid collection rate is calculated using the following formula: θ = (M1 + M2) / M_total × 100% Where: θ is the total collection rate of mixed waste liquid, in %, with a value of ≥93%; M1 is the mass flow rate of condensate from the vented condenser, in kg / h; M2 is the mass flow rate of vented liquid from the distillation unit, in kg / h; Mtotal is the theoretical total mass flow rate of collectable waste liquid based on distillation material balance, in kg / h. S4: Waste liquid is transferred in stages. When the liquid level in the waste liquid tank reaches the preset threshold, the mixed waste liquid is transferred to the high-sulfur waste liquid tank. The condensate from the venting and discharge liquid and the venting gas is collected together to avoid the waste of condensable liquid in the venting gas by burning with the gas phase. At the same time, the mixed waste liquid is temporarily stored in the high-sulfur waste liquid tank. The high-sulfur components can be recovered later as chemical raw materials. The resource utilization rate is greatly improved compared with the traditional separate treatment process. The mixed waste liquid transfer uses a variable frequency transfer pump, which is automatically started and stopped by an intelligent control module based on the liquid level threshold of the waste liquid tank. The automatic transfer triggering and stopping control of the mixed waste liquid is achieved through the following threshold linkage algorithm: , The transfer is initiated when Lactual ≥ Ltouch. , The transfer should be stopped when ttransfer ≥ tstop. Wherein: t touch is the pre-judgment time of the liquid level rising from the initial value to the trigger threshold, unit: h, used to activate the standby state of the variable frequency conveying pump in advance; L real is the real-time liquid level of the waste liquid tank, unit: % tank capacity; L initial is the initial liquid level of the transfer cycle, unit: % tank capacity, taking the liquid level value at the last transfer stop; v L is the average rising rate of the liquid level, unit: % tank capacity / h, calculated by the change amount of L real in the last 10 minutes, ; L touch is the transfer start threshold liquid level, unit: % tank capacity, preset as 75%-85% tank capacity; t stop is the pre-judgment stop time required for a single transfer, unit: h, to ensure that the liquid level drops to a safe range after transfer; L safe is the safe liquid level after transfer stop, unit: % tank capacity, preset as 15%-20% tank capacity, reserving a buffer space; V tank is the effective volume of the waste liquid tank, unit: L; Q pump is the rated conveying flow of the variable frequency conveying pump, unit: L / h; t run is the actual running time of the variable frequency conveying pump, unit: h, recorded by the intelligent control module in real time; S5: tail gas terminal treatment, the tail gas treatment module burns the uncondensed gas phase at 800-850℃, and discharges after reaching the standard. When judging the standard, the removal rate of harmful components of the tail gas treatment module is calculated by the following formula: η=[(C1-C2) / C1]×100%, Wherein: η is the removal rate of harmful components, unit: %, ≥99%; C1 is the concentration of harmful components in the gas phase at the outlet of the vent condenser, unit: mg / m³; C2 is the concentration of harmful components in the tail gas at the outlet of the tail gas treatment module, unit: mg / m³. Example two

[0022] According to Figure 1 , 2 The present embodiment proposes a rectification tail gas multi-component separation and recycling device and method, applied to a conventional load working condition, and the rectification unit has a treatment capacity of 800 kg / h: The venting liquid lifting tank V507 has a volume of 10 m³ and a liquid level control range of 30%-70%; The vent condenser E520 has a condensing temperature of 45℃ and a condensing pressure of 0.3 MPa; The waste liquid tank V506 has a volume of 8 m³ and a liquid level threshold (start transfer) of 80%; The RTO device has a combustion temperature of 820℃ and a flue gas residence time of 2s.

[0023] Verification data: The removal rate of harmful components: η=[(C1-C2) / C1]×100% Wherein: η is the removal rate of harmful components after RTO treatment (%); C1 is the concentration of harmful components in the gas phase at the outlet of the vent condenser (mg / m³), which is measured as 1200 mg / m³; C2 is the concentration of harmful components in the tail gas at the outlet of the RTO (mg / m³), which is measured as 10 mg / m³; It is calculated that: η = [(1200-10) / 1200] × 100% = 99.17%.

[0024] Waste liquid collection rate: θ = (M1+M2) / Mtotal × 100% Wherein: θ is the total collection rate of mixed waste liquid (%); M1 is the mass flow rate of condensate from the vent condenser (kg / h), which is measured as 40 kg / h; M2 is the mass flow rate of waste liquid discharged from the vent of the rectification unit (kg / h), which is measured as 30 kg / h; Mtotal is the total mass flow rate of theoretically collectable waste liquid (kg / h), which is calculated as 72 kg / h (based on the material balance of the rectification); It is calculated that: θ = (40+30) / 72 × 100% = 97.22%. Example Three

[0025] According to Figure 1 , 2 The present embodiment proposes a device and method for multi-component separation and recycling of rectification tail gas, which is applied to high load conditions, and the processing capacity of the rectification unit is 1200 kg / h: Vent condenser E520: condensation temperature 50℃, condensation pressure 0.4MPa, temperature control accuracy ±0.5℃; Vent condenser E520: condensation temperature 50℃, condensation pressure 0.4MPa, temperature control accuracy ±0.5℃; Waste liquid tank (V506): effective volume 8000L, liquid level starting threshold set to 75% of tank capacity (6000L), safety stop liquid level set to 18% of tank capacity (1440L), liquid level sensor collects data in real time; Variable frequency delivery pump: rated delivery flow rate 180L / h, linked with intelligent control module, supporting standby-start-stop automatic switching; RTO device: combustion temperature 850℃, flue gas residence time 2.5s, outlet flue gas online monitoring frequency 1 time / 2 minutes.

[0026] Operation process and verification data: VOCs emission and liquid waste collection: The rectification unit generates about 150 m³ of emission gas (containing VOCs concentration of 1800 mg / m³) and 45 kg / h of vented liquid waste per hour; the emission gas enters the vent condenser after being buffered by the vent liquid lifting tank, and is condensed to generate 65 kg / h of condensed liquid (density of 1 kg / L, i.e. 65 L / h), which is mixed with the vented liquid waste (45 L / h at 1 kg / L) and then enters the waste liquid tank at a rate of 110 L / h.

[0027] Automatic transfer control: The intelligent control module collects the liquid level data of the waste liquid tank in real time, and the initial liquid level is 18% (1440 L) of the tank capacity at the stop of the previous round of transfer. After running for 10 minutes, the liquid level rises to 28% (2240 L) of the tank capacity, and the average rising rate of the liquid level is calculated to be 0.6% of the tank capacity per hour (i.e. 48 L / h). The module predicts that the liquid level will rise from the current 28% to the starting threshold of 75%, which will take about 79 minutes. Five minutes in advance, the frequency conversion pump is activated in standby state. When the liquid level reaches 75% (6000 L), the automatic start is activated, and the module simultaneously predicts that the liquid level needs to be reduced to 18% in a single transfer. Combined with the effective volume of the waste liquid tank and the rated flow of the pump, it is calculated that the pump needs to run for about 25 minutes. After actually running for 24.8 minutes, the liquid level is reduced to 18.2%, and the pump is automatically stopped to avoid cavitation caused by low liquid level.

[0028] Environmental protection and resource utilization indicators: The concentration of harmful components at the outlet of the RTO device is measured to be 15 mg / m³, and the removal rate is 99.17%; the total collection amount of mixed waste liquid is 110 kg / h (condensed liquid 65 kg / h + vented liquid waste 45 kg / h), and the theoretical collectable amount is 115 kg / h, and the collection rate is 95.65%; the high-sulfur waste liquid tank receives 880 kg of mixed waste liquid every 8 hours, and the subsequent extraction process recovers high-sulfur components with a purity of 92%, and the resource recovery rate meets the design requirements. Example Four

[0029] According to Figure 1 , 2 , the present embodiment proposes a rectification tail gas multi-component separation and recycling device and method, which is applied to low load conditions, and the processing capacity of the rectification unit is 400 kg / h: Vent liquid lifting tank V507: volume 10 m³, liquid level sensor sampling frequency 1 time / 2 minutes; Vent condenser E520: condensation temperature 38℃, condensation pressure 0.2 MPa, temperature control accuracy ±0.5℃; Waste liquid tank (V506): effective volume 8000 L, liquid level starting threshold set to 85% of the tank capacity (6800 L), and safety stop liquid level set to 20% of the tank capacity (1600 L); Frequency conversion pump: rated delivery flow 120 L / h, supporting intermittent operation mode under low load; RTO device: combustion temperature 800℃, flue gas residence time 1.8s, outlet flue gas online monitoring frequency 1 time / 5 minutes.

[0030] Operation process and verification data Diffusion gas and liquid discharge collection: the rectification unit generates diffusion gas of about 50m³ / h (containing VOCs concentration of 600mg / m³) and venting liquid discharge of 12kg / h per hour; after buffering through the venting liquid lifting tank, the diffusion gas enters the venting condenser for condensation, generating condensate of 18kg / h (18L / h) per hour, which is mixed with the venting liquid discharge (12L / h) and then enters the waste liquid tank at a rate of 30L / h.

[0031] Automatic transfer control: the intelligent control module initially collects the liquid level of 20% (1600L), and after running for 30 minutes, the liquid level rises to 25% (2000L), and the average rising rate of the liquid level is calculated to be 0.1% tank capacity / h (i.e. 8L / h); the module predicts that the liquid level will rise from 25% to 85% to start the threshold, which will take about 750 minutes, and the frequency conversion pump will be activated in standby state 10 minutes in advance. When the liquid level reaches 85% (6800L), the frequency conversion pump is automatically started, and the module predicts that it needs to run for about 43 minutes (the liquid level is reduced from 6800L to 1600L); after actually running for 42.5 minutes, the liquid level is reduced to 20.5%, and the pump is automatically stopped to avoid energy waste caused by frequent start and stop of the pump under low load.

[0032] Environmental protection and resource utilization index: the concentration of harmful components at the outlet of the RTO device is actually measured to be 5mg / m³, and the removal rate is 99.17%; the total collection amount of mixed waste liquid is 30kg / h (condensate 18kg / h + venting liquid discharge 12kg / h), and the theoretical collectable amount is 32kg / h, and the collection rate is 93.75%; the high-sulfur waste liquid tank receives mixed waste liquid of 720kg every 24 hours, the purity of high-sulfur components recovered by subsequent distillation reaches 91%, and there is no situation that the liquid level fluctuation exceeds ±2% during the transfer process, and the system runs stably.

[0033] The present application removes 80%-90% of condensable components in the diffusion gas through two-stage treatment of condensation and separation, RTO incineration, reduces the load of RTO treatment, and greatly improves the removal rate of harmful components through high-temperature incineration of 800-850℃, to meet the latest environmental protection emission standard. The present application cooperatively collects the venting liquid discharge and the condensate of the diffusion gas, avoids the waste of condensable liquid in the diffusion gas with gas phase incineration, and temporarily stores the mixed waste liquid in the high-sulfur waste liquid tank, which can be used as a chemical raw material for recycling high-sulfur components, and the resource utilization rate is greatly improved compared with the traditional separate treatment process. At the same time, the intelligent control module monitors the liquid level of the venting liquid lifting tank, the temperature of the venting condenser, and the liquid level of the waste liquid tank in real time, avoids the equipment vibration caused by airflow impact and the leakage caused by out-of-control liquid level, reduces the fuel consumption of RTO through condensation pretreatment, and reduces the system operation cost.

[0034] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A distillation tail gas multi-component separation and recycling device, comprising a distillation unit, a venting collection module, a condensation separation module, a tail gas treatment module, a waste liquid collection module and an intelligent control module; characterized in that: The distillation unit is equipped with a venting gas outlet and a venting liquid outlet; the venting collection module is a venting liquid lifting tank, the inlet of which is connected to the venting gas outlet of the distillation unit; the condensation and liquid separation module is a venting condenser, the gas phase inlet of which is connected to the outlet of the venting liquid lifting tank, the gas phase outlet is connected to the tail gas treatment module, and the liquid phase outlet is connected to the waste liquid collection module. The waste liquid collection module includes a waste liquid tank and a high-sulfur waste liquid tank. The inlet of the waste liquid tank is connected to the liquid phase outlet of the venting condenser and the venting outlet of the distillation unit, respectively. The outlet of the waste liquid tank is connected to the high-sulfur waste liquid tank. The intelligent control module is electrically connected to the venting condenser, the venting condenser, and the waste liquid tank, respectively, and is used to regulate the liquid level and temperature parameters.

2. A distillation tail gas multi-component separation and recovery device according to claim 1, characterized in that: The condensing temperature of the vented condenser is adjustable from 35 to 55°C, and the condensing pressure is adjustable from 0.2 to 0.4 MPa.

3. The apparatus for multi-component separation and recovery of distillation off-gas according to claim 1, characterized in that: The waste liquid tank has an adjustable liquid level threshold, and the adjustable range of the waste liquid tank is 75%-85% of the tank capacity.

4. The apparatus for multi-component separation and recovery of distillation off-gas according to claim 1, wherein: The exhaust gas treatment module is an RTO incinerator with a combustion temperature range of 800-850℃ and a flue gas residence time of 1.8-2.5s.

5. The apparatus for multi-component separation and recovery of distillation off-gas according to claim 1, characterized in that: The venting and liquid-lifting tank has built-in baffles to reduce the flow rate of the released gas and reduce droplet entrainment.

6. A method for multi-component separation and recycling of distillation tail gas, using the multi-component separation and recycling device of any one of claims 1-5, characterized in that, Includes the following steps: S1: Gas collection, the gas released from the distillation unit is introduced into the venting and liquid lifting tank for buffering. S2: Condensation and liquid separation treatment. Start the venting condenser to condense and release gas at 35-55℃. Condensable liquid phase is introduced into waste liquid tank, and non-condensable gas phase is introduced into tail gas treatment module. S3: Vent and drain liquid collection, the vent and drain liquid from the distillation unit is directly introduced into the waste liquid tank and mixed with the condensate; S4: Waste liquid is transferred in stages. When the liquid level in the waste liquid tank reaches the preset threshold, the mixed waste liquid is transferred to the high-sulfur waste liquid tank. S5: Exhaust gas terminal treatment. The exhaust gas treatment module incinerates the uncondensed gas phase at 800-850℃, and the gas is discharged after meeting the standards.

7. The method of claim 6, wherein: In step S3, the waste liquid collection rate is calculated using the following formula: θ = (M1 + M2) / M_total × 100% Where: θ is the total collection rate of mixed waste liquid, in %, with a value of ≥93%; M1 is the mass flow rate of condensate from the vented condenser, in kg / h; M2 is the mass flow rate of vented liquid from the distillation unit, in kg / h; M_total is the theoretical total mass flow rate of collectable waste liquid based on distillation material balance, in kg / h.

8. The method of claim 6, wherein: In step S4, the mixed waste liquid is transferred using a variable frequency delivery pump, which is automatically started and stopped by an intelligent control module based on the liquid level threshold of the waste liquid tank.

9. The method of claim 8, wherein: In the S4, the automatic transfer trigger and stop control of the mixed waste liquid is realized by the following threshold linkage algorithm: , Transport is initiated when Lact > Ltouch , The transfer should be stopped when ttransfer ≥ tstop. Wherein: t touch is the pre-judgment time for the liquid level to rise from the initial value to the trigger threshold, unit: h, used to activate the standby state of the variable frequency conveying pump in advance; L real is the real-time liquid level of the waste liquid tank, unit: % tank capacity; L initial is the initial liquid level of the transfer cycle, unit: % tank capacity, taking the liquid level value at the last transfer stop; v L is the average rising rate of the liquid level, unit: % tank capacity / h, calculated by the change amount of L real in the last 10 minutes, ; L touch is the transfer start threshold liquid level, unit: % tank capacity, preset as 75%-85% tank capacity; t stop is the pre-judgment stop time required for a single transfer, unit: h, to ensure that the liquid level drops to a safe range after transfer; L safe is the safe liquid level after transfer stop, unit: % tank capacity, preset as 15%-20% tank capacity, reserving a buffer space; V tank is the effective volume of the waste liquid tank, unit: L; Q pump is the rated conveying flow of the variable frequency conveying pump, unit: L / h; t run is the actual running time of the variable frequency conveying pump, unit: h, recorded by the intelligent control module in real time.

10. The method of claim 6, wherein: In step S5, when determining compliance, the removal rate of harmful components in the exhaust gas treatment module is calculated using the following formula: η = [(C1-C2) / C1] × 100%, Where: η is the removal rate of harmful components, in %, with a value of ≥99%; C1 is the concentration of harmful components in the gas phase at the outlet of the vent condenser, in mg / m³; C2 is the concentration of harmful components in the exhaust gas at the outlet of the exhaust gas treatment module, in mg / m³.

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