Method and system for separating organic components in gas

Abstract

The invention relates to the technical field of organic waste gas treatment, in particular to a method and system for separating organic components in gas. The method for separating the organic components in the gas comprises the following steps: absorbing and purifying; carrying out inclusion treatment; and repeatedly absorbing and clathrating. According to the method, the absorption liquid for absorbing the gas containing the organic components is subjected to inclusion promotion treatment, so that the organic matters in the absorption liquid are promoted to form an embedded complex structure which is more stable than dissolution, and the included organic components in the absorption liquid are not included in the liquid phase concentration in the gas dissolution theory any more; the absorption liquid after inclusion promotion has the capability of absorbing the organic components in the gas again under the requirements of gas concentration emission limitation and new gas-liquid phase balance, and at the moment, the absorption liquid can return to the absorption and purification step to absorb the organic components in the gas again without replacement or regeneration, so that the frequency of replacement or regeneration of the absorption liquid is greatly reduced; the operation cost is lower, and the commercial value is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of organic waste gas treatment, and in particular to a method and system for separating organic components in gas. Background Art

[0002] Volatile organic compounds (VOCs) refer to any organic compound with a boiling point below 250°C at normal pressure or a saturated vapor pressure exceeding 133.32 Pa at room temperature (25°C) that is emitted into the air in the form of gaseous molecules. VOCs are not only highly toxic in themselves, but are also important precursors and participants that affect atmospheric complex pollution. Therefore, controlling VOCs is of great significance to improving the quality of the atmospheric environment.

[0003] There are currently several main types of VOCs treatment: a) thermal oxidation processes including catalytic thermal oxidation, direct thermal oxidation and thermal storage thermal oxidation; b) physical adsorption processes using porous materials such as activated carbon, zeolite and silica to physically adsorb and capture VOCs; c) absorption processes including liquid absorption with organic solvents, chemical reaction absorption by acid washing or alkaline washing; d) biological treatment; e) medium excitation (UV photolysis / low temperature plasma) processes. Among them, the absorption process generally uses acid-base neutralization to treat inorganic waste gases such as acid mist, alkaline mist, ammonia, nitrogen oxides, and sulfur dioxide. However, in actual applications, the absorption method for organic waste gas is only applicable to high concentrations (about 3000-5000mg / m 3 The absorption effect can only be achieved in a very short time (about 1-60 minutes, when the liquid phase concentration and gas phase concentration after absorption can meet the phase equilibrium theory), and the absorption liquid needs to be regenerated at this time, resulting in high investment or operating costs and difficulty in commercialization. For example, when water is used as the absorption liquid and a packed tower equipment is used to absorb ethanol gas, if the ethanol emission concentration is 70mg / m 3 According to the data, the saturated vapor pressure of ethanol in the gas at 25°C is 7.927 kPa. According to the phase equilibrium equation, the corresponding maximum molar concentration of ethanol in the absorption liquid can be calculated to be 0.000474 mol / L, and the converted mass concentration is 0.12%. That is, if the absorption liquid is 1m 3 , exhaust gas concentration is 200mg / m 3 、Exhaust air volume is 10000m 3 / h, it is calculated that the absorption liquid needs to be replaced or regenerated every 55 minutes. However, in practical applications, it is difficult to frequently replace or regenerate the absorption liquid, and it is difficult to realize commercialization. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect of the existing liquid absorption method that the absorption liquid needs to be frequently replaced or regenerated, thereby providing a method and system for separating organic components in gas to solve the above problem.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A method for separating organic components in gas, comprising:

[0007] Absorption purification: The gas containing organic components is subjected to absorption purification treatment using an absorption liquid with inclusion capacity to obtain the absorbed absorption liquid;

[0008] Inclusion treatment: transporting the absorbed absorption liquid to an inclusion promotion device for inclusion promotion treatment to obtain the absorbed absorption liquid after inclusion;

[0009] Repeated absorption and inclusion: The absorption liquid after inclusion is repeatedly absorbed, purified and included in turn.

[0010] Preferably, in the repeated absorption and inclusion step, the absorption purification and inclusion treatment steps are repeated in sequence until the inclusion capacity of the absorption liquid is saturated;

[0011] And / or, the inclusion promotion treatment comprises at least one of microwave, ultrasound, stirring, cooling and pressurizing;

[0012] And / or, after the repeated absorption and inclusion step, the absorption liquid after repeated absorption and inclusion is regenerated to separate the organic components, and the absorption liquid after the regeneration treatment recovers the absorption and inclusion capacity and returns to the absorption and purification step for repeated use; optionally, the regeneration treatment includes distillation.

[0013] Preferably, the absorption purification treatment duration is 5-180 min; and / or the inclusion treatment duration is 5-360 min.

[0014] Preferably, the absorption liquid with inclusion capacity comprises: 1-40 wt % inclusion agent, 0.1-20 wt % functional additive, and 40-99 wt % solvent.

[0015] Preferably, the inclusion agent is cyclodextrin and its derivatives, preferably at least one of α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, methyl-β-cyclodextrin and cyclodextrin polymer;

[0016] And / or, the functional additives include but are not limited to at least one of a solubilizer, a cosolvent, a dispersant, an emulsifier, an antioxidant, an anti-yellowing agent, an anti-corrosion agent, and a defoaming agent;

[0017] And / or, the solvent is water.

[0018] In actual use, the absorption liquid adjusts the pH value as needed by adding sodium hydroxide, potassium hydroxide and other substances, and adds defoaming agents such as silicone oil and polyether to avoid foam affecting the absorption process. Surfactants such as polyvinyl pyrrolidone, sodium citrate, FMES (sulfonate of fatty acid methyl ester ethoxylate), sodium dodecylbenzene sulfonate, etc. are added to increase the solubility of the inclusion agent or organic components in the gas. The presence of a small amount of other substances in the liquid that have little effect on the absorption and inclusion capacity are all regarded as natural derivatives of the absorption liquid and are within the scope of protection of the absorption liquid of the present invention.

[0019] The present invention also provides a separation system for organic components in gas, which is used to perform the above-mentioned separation method for organic components in gas, and comprises a gas-liquid absorption device and an inclusion promotion device which are interconnected to form a circulation loop; the gas-liquid absorption device is filled with an absorption liquid with inclusion capacity, and the inclusion promotion device is equipped with at least one of microwave equipment, ultrasonic equipment, stirring equipment, and cooling and pressurizing equipment.

[0020] Preferably, the gas-liquid absorption device is a gas-liquid contact and mass transfer device, preferably at least one of a packed tower, a plate tower, a bubbling tower, a venturi tube, and a supergravity absorption tower.

[0021] Preferably, the outlet of the gas-liquid absorption device and / or the outlet of the inclusion promotion device is also connected to an absorption liquid regeneration separation device, and the absorption liquid outlet of the absorption liquid regeneration separation device is connected to the inlet of the gas-liquid absorption device.

[0022] Preferably, the outlet of the inclusion promoting device is connected to the inlet of the gas-liquid absorption device through a first circulation pipeline, and the absorption liquid outlet of the absorption liquid regeneration separation device is connected to the inlet of the gas-liquid absorption device through a second circulation pipeline. Circulation pumps are provided on the first circulation pipeline and the second circulation pipeline to realize a small circulation of the absorption liquid in the gas-liquid absorption device and the inclusion promoting device, and a large circulation of the absorption liquid in the gas-liquid absorption device, the inclusion promoting device and the absorption liquid regeneration separation device.

[0023] Preferably, the absorption liquid regeneration and separation device includes atmospheric distillation equipment and / or reduced pressure distillation equipment.

[0024] In the present invention, the absorption liquid can be treated by continuous circulation or directly switched. When directly switching the treatment, the absorption purification time is adjusted according to the concentration of organic components in the outlet gas of the absorption purification treatment. When the organic components in the outlet gas are close to or reach the maximum allowable emission limit of the emission standard, the absorption liquid is completely switched to carry out inclusion promotion treatment.

[0025] The technical solution of the present invention has the following advantages:

[0026] A method for separating organic components in gas comprises: absorption purification: using an absorption liquid with inclusion capacity to absorb and purify the gas containing organic components to obtain an absorption liquid after absorption; inclusion treatment: transporting the absorption liquid after absorption to an inclusion promotion device for inclusion promotion treatment to obtain an absorption liquid after inclusion; repeated absorption and inclusion: repeating the absorption purification and inclusion treatment of the absorption liquid after inclusion. The present invention promotes the organic matter in the absorption liquid to form an inclusion complex structure that is more stable than dissolved by subjecting the absorption liquid for absorbing the gas containing organic components to inclusion promotion treatment, and the organic components after inclusion in the absorption liquid are no longer included in the liquid phase concentration in the gas dissolution theory, so that the absorption liquid after inclusion promotion has the ability to absorb the organic components in the gas again under the gas concentration emission limit and the new gas-liquid phase equilibrium requirement. At this time, it can return to the absorption purification step to absorb the organic components in the gas again without replacement or regeneration, thereby greatly reducing the frequency of replacement or regeneration of the absorption liquid, and has lower operating costs and higher commercial value. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 This is a composition and process flow diagram of the separation system for organic components in gas in Example 1 of the present invention. DETAILED DESCRIPTION

[0029] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0030] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0031] Example 1

[0032] This embodiment provides a system for separating organic components in gas, such as Figure 1As shown, it includes a gas-liquid absorption device (plate tower) and an inclusion promotion device (ultrasonic device) connected in sequence, and also includes an absorption liquid regeneration separation device (normal pressure distillation equipment), a pipeline and a circulation pump, wherein the gas-liquid absorption device is filled with absorption liquid, and the specific components and proportions of the absorption liquid are: the inclusion agent is 1wt% α-cyclodextrin, 5wt% β-cyclodextrin, 10wt% hydroxypropyl-β-cyclodextrin; the functional additive is 2wt% polyethylene glycol 600, 0.5wt% polyoxyethylene polymer, 0.5wt% propylene glycol block polyether; the solvent is 81wt% water. The gas-liquid absorption device constructs an absorption liquid absorption-inclusion promotion bidirectional circulation channel (small circulation) with the inclusion promotion device through the pipeline, and at the same time, the gas-liquid absorption device, the inclusion promotion device and the absorption liquid regeneration separation device are also connected in sequence through the pipeline to construct an absorption liquid absorption-inclusion promotion-regeneration separation circulation channel (large circulation), and a circulation pump is also arranged on the pipeline to provide power for the absorption liquid to circulate between the devices.

[0033] The specific steps of using the separation system of organic components in gas in this embodiment to treat organic waste gas are as follows:

[0034] 1) The organic waste gas is passed into the plate tower and absorbed by the above absorption liquid for 40 minutes. The air volume of the organic waste gas is 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 11 mg / m 3 , the concentration of xylene is 15mg / m 3 , the concentration of ethyl acetate is 26mg / m 3 , to achieve compliance (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 )emission;

[0035] 2) All the absorbed liquid is switched and transported through pipelines to an ultrasonic device (the ultrasonic device is equipped with 20 80W ultrasonic vibrators) for treatment for 40 minutes to promote the organic matter in the absorption liquid to form inclusion compounds that are more stable than dissolved, so as to regain the ability to absorb organic waste gas;

[0036] 3) The absorption liquid after ultrasonic treatment in step 2) is transported back to the plate tower for organic waste gas absorption, and steps 1)-2) are repeated. After the total time of the absorption purification operation in step 1) reaches 400 minutes and the total time of the ultrasonic operation in step 2) reaches 400 minutes, the inclusion capacity of the absorption liquid is saturated and needs to be regenerated;

[0037] 4) transporting the saturated absorption liquid from step 3) to an atmospheric distillation device for regeneration treatment at a distillation temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0038] 5) The liquid form of the organic waste gas in the upper layer of the mixed liquid (the mass of the liquid form of the organic waste gas is about 520g) is separated and recycled, and the water separated from the lower layer of the mixed liquid is added to the regenerated absorption liquid, and after cooling to room temperature, it is re-transported to the plate tower for recycling, and continues to work for 800 minutes (the total time for absorption and purification reaches 400 minutes, and the total time for ultrasonic operation reaches 400 minutes), the absorption liquid is heated to 105°C at normal pressure for 20 minutes, the temperature is kept boiling for 30 minutes, and regenerated once.

[0039] Example 2

[0040] This embodiment provides a method for treating organic waste gas based on absorption inclusion method. The system for treating organic waste gas based on absorption inclusion method in this embodiment is the same as that in Example 1. The specific components and proportions of the absorption liquid are: the inclusion agent is 1wt% γ-cyclodextrin and 20wt% hydroxypropyl-β-cyclodextrin; the functional additive is 1wt% silicone oil defoamer and 1wt% fatty alcohol vinyl ether polymer; the solvent is 77wt% water. The specific steps are as follows:

[0041] 1) The organic waste gas is passed into the plate tower and absorbed by the above absorption liquid for 60 minutes. The air volume of the organic waste gas is 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 400mg / m 3 , the concentration of xylene is 400mg / m 3 , the concentration of ethyl acetate is 400 mg / m 3 ; The concentration of styrene in the outlet gas is 16 mg / m 3 , the concentration of xylene is 23mg / m 3 , the concentration of ethyl acetate is 38mg / m 3 , to achieve compliance (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 )emission;

[0042] 2) All the absorbed liquid is switched and transported to a microwave device (power 3kw) through a pipeline for treatment for 5 minutes, cooled by 5°C and kept still for 55 minutes to promote the organic matter in the absorption liquid to form a more stable inclusion compound than dissolved organic matter, so as to regain the ability to absorb organic waste gas;

[0043] 3) The absorption liquid after microwave treatment in step 2) is transported back to the plate tower for organic waste gas absorption, and steps 1)-2) are repeated. After the total time of performing the absorption purification operation in step 1) reaches 600 minutes, performing microwave treatment in step 2) and cooling and standing for 600 minutes, the inclusion capacity of the absorption liquid is close to saturation and needs to be regenerated;

[0044] 4) The saturated absorption liquid in step 3) is transported to a vacuum distillation device at a treatment pressure of 0.047 MPa and a temperature of 80° C., and fractionated to obtain a liquid mixture of water and organic waste gas and a regenerated absorption liquid;

[0045] 5) The liquid form of the organic waste gas in the upper layer of the mixed liquid (the mass of the liquid form of the organic waste gas is about 1930g) is separated and recycled, and the water separated from the lower layer of the mixed liquid is added to the regenerated absorption liquid, and after cooling to room temperature, it is re-transported to the plate tower for recycling, and the work is continued for 1200min (the total absorption and purification treatment time is 600min, and the total microwave and cooling and standing time is 600min), the absorption liquid is heated to 85°C for 15 minutes under reduced pressure, the temperature is kept boiling for 30min, and regenerated once.

[0046] Example 3

[0047] This embodiment provides a method for treating organic waste gas based on absorption inclusion method. The system for treating organic waste gas based on absorption inclusion method in this embodiment is the same as that in Embodiment 1. The specific steps are as follows:

[0048] 1) The organic waste gas was introduced into the plate tower and absorbed by the same absorption liquid as in Example 1 for 40 min. The air volume of the organic waste gas was 200 m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 11 mg / m 3 , the concentration of xylene is 15mg / m 3, the concentration of ethyl acetate is 26mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0049] 2) All the absorbed liquid is switched and transported to a stirring device (stirring parameter is 100 rpm / min) through a pipeline for 180 min to promote the organic matter in the absorption liquid to form a more stable inclusion compound than dissolved organic matter, so as to regain the ability to absorb organic waste gas;

[0050] 3) The absorption liquid after the stirring treatment in step 2) is transported back to the plate tower to absorb the organic waste gas, and steps 1)-2) are repeated. After the total time of the absorption and purification operation in step 1) reaches 400 minutes and the total time of the stirring operation in step 2) reaches 1800 minutes, the absorption liquid inclusion capacity is saturated and needs to be regenerated;

[0051] 4) transporting the saturated absorption liquid from step 3) to an atmospheric distillation device for regeneration treatment at a distillation temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0052] 5) The liquid form of the organic waste gas in the upper layer of the mixed liquid (the mass of the liquid form of the organic waste gas is about 360g) is separated and recycled, and the water separated from the lower layer of the mixed liquid is added to the regenerated absorption liquid, and after cooling to room temperature, it is re-transported to the plate tower for recycling, and continues to work for 2200min (the total time for absorption and purification reaches 400min, and the total time for stirring operation reaches 1800min), the absorption liquid is heated to 105°C at normal pressure for 20 minutes, the temperature is kept boiling for 30min, and regenerated once.

[0053] Example 4

[0054] This embodiment provides a method for treating organic waste gas based on absorption inclusion method. The system for treating organic waste gas based on absorption inclusion method in this embodiment is the same as that in Embodiment 1. The specific steps are as follows:

[0055] 1) The organic waste gas was introduced into the plate tower and absorbed by the same absorption liquid as in Example 1 for 40 min. The air volume of the organic waste gas was 200 m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 11 mg / m 3 , the concentration of xylene is 15mg / m 3 , the concentration of ethyl acetate is 26mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0056] 2) All the absorbed liquid is switched and transported through pipelines to a cooling and pressurizing device (temperature 4°C, pressure 2atm) for treatment for 360 minutes to promote the organic matter in the absorption liquid to form a more stable inclusion complex than dissolved organic matter, so as to regain the ability to absorb organic waste gas;

[0057] 3) The absorption liquid after the cooling and pressurizing treatment in step 2) is transported back to the plate tower for organic waste gas absorption, and steps 1)-2) are repeated. After the total time of the absorption and purification operation in step 1) reaches 400 minutes and the total time of the cooling and pressurizing operation in step 2) reaches 3600 minutes, the absorption liquid inclusion capacity is saturated and needs to be regenerated;

[0058] 4) transporting the saturated absorption liquid from step 3) to an atmospheric distillation device for regeneration treatment at a distillation temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0059] 5) The liquid form of the organic waste gas in the upper layer of the mixed liquid (the mass of the liquid form of the organic waste gas is about 610g) is separated and recycled, and the water separated from the lower layer of the mixed liquid is added to the regenerated absorption liquid, and after cooling to room temperature, it is re-transported to the plate tower for recycling, and continues to work for 4000min (the total time for absorption and purification reaches 400min, and the total time for cooling and pressurizing operation reaches 3600min), the absorption liquid is heated to 105°C at normal pressure for 20 minutes, the temperature is kept boiling for 30min, and regenerated once.

[0060] Comparative Example 1

[0061] This comparative example provides a method for treating organic waste gas, without performing ultrasonic-promoted inclusion treatment, and directly performing regeneration treatment when the absorption liquid in the gas-liquid absorption device has no absorption treatment effect. The specific steps are as follows:

[0062] 1) The organic waste gas was introduced into the plate tower and absorbed by the same absorption liquid as in Example 1 for 40 min. The air volume of the organic waste gas was 200 m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 11 mg / m 3 , the concentration of xylene is 15mg / m 3 , the concentration of ethyl acetate is 26mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0063] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 50 minutes of absorption, the concentration of styrene in the outlet gas is 32 mg / m 3 , the concentration of xylene is 41mg / m 3 , the concentration of ethyl acetate is 67mg / m 3 , the emission exceeded the standard; when the absorption continued for 80 minutes, the concentration of styrene in the outlet gas was 200 mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 , the system no longer has any absorption processing effect.

[0064] 3) transporting the saturated absorption liquid in step 1) to an atmospheric distillation device for regeneration treatment at a temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0065] 4) The mass of the liquid form of the obtained organic waste gas is about 75g, and the water mixed with it after boiling for 30 minutes is about 17L. The cost-effectiveness of recycling the liquid component of the organic waste gas is low; after 40 minutes of absorption, distillation and regeneration absorption is required once. Each distillation and heating to boiling and boiling until the absorbed organic waste gas components are fully separated takes about 50 minutes. The system has high energy consumption, and because the distillation and regeneration time of the absorption liquid is greater than the sustainable absorption time, it cannot be actually applied in engineering practice.

[0066] Comparative Example 2

[0067] This comparative example provides a method for treating organic waste gas, without microwave inclusion promotion treatment, and directly regenerating the absorbing liquid when the absorbing liquid in the gas-liquid absorption device has no absorbing treatment effect. The specific steps are as follows:

[0068] 1) The organic waste gas was introduced into the plate tower and absorbed by the same absorption liquid as in Example 2 for 60 min. The air volume of the organic waste gas was 200 m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 400mg / m 3 , the concentration of xylene is 400mg / m 3 , the concentration of ethyl acetate is 400 mg / m 3 ; The concentration of styrene in the outlet gas is 16 mg / m 3 , the concentration of xylene is 23mg / m 3 , the concentration of ethyl acetate is 38mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0069] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 80 minutes of absorption, the concentration of styrene in the outlet gas is 115 mg / m 3 , the concentration of xylene is 136mg / m 3 , the concentration of ethyl acetate is 211mg / m 3 , the emission exceeded the standard; when the absorption continued to 90 minutes, the concentration of styrene in the outlet gas was 400mg / m 3 , the concentration of xylene is 400mg / m 3 , the concentration of ethyl acetate is 400 mg / m 3 , the system no longer has any absorption processing effect.

[0070] 3) The saturated absorption liquid of step 1) is transported to a vacuum distillation device for regeneration treatment at a treatment pressure of 0.047 MPa and a temperature of 80° C., and fractionated to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid.

[0071] 4) The mass of the liquid form of the obtained organic waste gas is about 150g, and the water mixed with it after boiling for 30 minutes is about 17L. The cost-effectiveness of recycling the liquid component of the organic waste gas is low; after 60 minutes of absorption, distillation and regeneration absorption is required once. Each distillation and heating to boiling and boiling until the absorbed organic waste gas components are fully separated takes about 50 minutes. The system has high energy consumption, and because the distillation and regeneration time of the absorption liquid is greater than the sustainable absorption time, it cannot be actually applied in engineering practice.

[0072] Comparative Example 3

[0073] This comparative example provides a method for treating organic waste gas, which is different from Example 1 in that ultrasonic treatment is performed while absorbing, and regeneration treatment is directly performed when the absorption liquid in the gas-liquid absorption device has no absorption treatment effect. The specific steps are as follows:

[0074] 1) The organic waste gas was introduced into a plate tower and the same absorption liquid as in Example 1 was used for absorption and the recycled absorption liquid was ultrasonically treated for 40 minutes. The air volume of the organic waste gas was 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 16 mg / m 3 , the concentration of xylene is 18mg / m 3 , the concentration of ethyl acetate is 32mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0075] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 50 minutes of absorption, the concentration of styrene in the outlet gas is 54 mg / m 3 , the concentration of xylene is 67mg / m 3 , the concentration of ethyl acetate is 83mg / m 3 , the emission exceeded the standard; when the absorption continued to 73 minutes, the concentration of styrene in the outlet gas was 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m3 , the system no longer has any absorption processing effect.

[0076] 3) transporting the saturated absorption liquid in step 1) to an atmospheric distillation device for regeneration treatment at a temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0077] 4) The mass of the liquid form of the obtained organic waste gas is about 78g, and the water mixed with it after boiling for 30 minutes is about 25L. The cost-effectiveness of recycling the liquid component of the organic waste gas is low; after 40 minutes of absorption, distillation and regeneration absorption is required once. Each distillation and heating to boiling and boiling until the absorbed organic waste gas components are fully separated takes about 50 minutes. The system has high energy consumption, and because the distillation and regeneration time of the absorption liquid is greater than the sustainable absorption time, it cannot be actually applied in engineering practice.

[0078] Comparative Example 4

[0079] This comparative example provides a method for treating organic waste gas, which is different from Example 2 in that microwave treatment is performed while absorbing, and regeneration treatment is directly performed when the absorption liquid in the gas-liquid absorption device has no absorption treatment effect. The specific steps are as follows:

[0080] 1) The organic waste gas was introduced into a plate tower and the same absorption liquid as in Example 2 was used for absorption and the recycled absorption liquid was subjected to microwave treatment for 30 minutes. The air intake of the organic waste gas was 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 400mg / m 3 , the concentration of xylene is 400mg / m 3 , the concentration of ethyl acetate is 400 mg / m 3 ; The concentration of styrene in the outlet gas is 15 mg / m 3 , the concentration of xylene is 22mg / m 3 , the concentration of ethyl acetate is 38mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0081] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 45 minutes of absorption, the concentration of styrene in the outlet gas is 33 mg / m 3, the concentration of xylene is 41mg / m 3 , the concentration of ethyl acetate is 72mg / m 3 , the emission exceeded the standard; when the absorption continued for 60 minutes, the concentration of styrene in the outlet gas was 400mg / m 3 , the concentration of xylene is 400mg / m 3 , the concentration of ethyl acetate is 400 mg / m 3 , the system no longer has any absorption processing effect.

[0082] 3) transporting the saturated absorption liquid in step 1) to an atmospheric distillation device for regeneration treatment at a temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0083] 4) The mass of the liquid form of the obtained organic waste gas is about 185g, and the water mixed with it after boiling for 30 minutes is about 17L. The cost-effectiveness of recycling the liquid component of the organic waste gas is low; after 30 minutes of absorption, distillation and regeneration absorption is required once. Each distillation and heating to boiling and boiling until the absorbed organic waste gas components are fully separated takes about 50 minutes. The system has high energy consumption, and because the distillation and regeneration time of the absorption liquid is greater than the sustainable absorption time, it cannot be actually applied in engineering practice.

[0084] Comparative Example 5

[0085] This comparative example provides a method for treating organic waste gas, which is different from Example 3 in that stirring is performed during absorption, and regeneration is performed directly when the absorption liquid in the gas-liquid absorption device has no absorption effect. The specific steps are as follows:

[0086] 1) The organic waste gas was introduced into a plate tower and absorbed by the same absorption liquid as in Example 1. The recycled absorption liquid was stirred for 40 minutes. The air volume of the organic waste gas was 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 10 mg / m 3 , the concentration of xylene is 14 mg / m 3 , the concentration of ethyl acetate is 24 mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0087] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 50 minutes of absorption, the concentration of styrene in the outlet gas is 21 mg / m 3 , the concentration of xylene is 26mg / m 3 , the concentration of ethyl acetate is 38mg / m 3 , the emission exceeded the standard; when the absorption continued for 60 minutes, the concentration of styrene in the outlet gas was 200 mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 , the system no longer has any absorption processing effect.

[0088] 3) transporting the saturated absorption liquid in step 1) to an atmospheric distillation device for regeneration treatment at a temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0089] 4) The mass of the liquid form of the obtained organic waste gas is about 97g, and the water mixed with it after boiling for 30 minutes is about 25L. The cost-effectiveness of recycling the liquid component of the organic waste gas is low; after 40 minutes of absorption, distillation and regeneration absorption is required once. Each distillation and heating to boiling and boiling until the absorbed organic waste gas components are fully separated takes about 50 minutes. The system has high energy consumption, and because the distillation and regeneration time of the absorption liquid is greater than the sustainable absorption time, it cannot be actually applied in engineering practice.

[0090] Comparative Example 6

[0091] This comparative example provides a method for treating organic waste gas, which is different from Example 4 in that a cooling and pressurizing treatment is performed while absorbing, and a regeneration treatment is directly performed when the absorbing liquid in the gas-liquid absorption device has no absorption treatment effect. The specific steps are as follows:

[0092] 1) The organic waste gas was introduced into a plate tower and absorbed by the same absorption liquid as in Example 1. The recycled absorption liquid was cooled and pressurized for 50 minutes. The air volume of the organic waste gas was 200m 3 / h, 50L of absorption liquid in the plate tower, sampling and analysis of the inlet and outlet gases, the analysis results are as follows: the concentration of styrene in the inlet gas is 200mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 ; The concentration of styrene in the outlet gas is 12 mg / m3 , the concentration of xylene is 17mg / m 3 , the concentration of ethyl acetate is 28mg / m 3 , achieve standard emissions (according to the requirements of Guangdong Province's "Comprehensive Emission Standards for Volatile Organic Compounds from Stationary Pollution Sources" (DB44 / 2367-2022), the maximum allowable concentration limit of benzene series is 40mg / m 3 The maximum allowable concentration limit of non-methane hydrocarbons is 80 mg / m 3 The maximum allowable concentration limit of total VOC is 100 mg / m 3 );

[0093] 2) All parameters in step 1) remain unchanged, and the organic waste gas absorption operation is continued. After 60 minutes of absorption, the concentration of styrene in the outlet gas is 26 mg / m 3 , the concentration of xylene is 29mg / m 3 , the concentration of ethyl acetate is 47mg / m 3 , the emission exceeded the standard; when the absorption continued to reach 75 minutes, the concentration of styrene in the outlet gas was 200 mg / m 3 , the concentration of xylene is 200mg / m 3 , the concentration of ethyl acetate is 200 mg / m 3 , the system no longer has any absorption processing effect.

[0094] 3) transporting the saturated absorption liquid in step 1) to an atmospheric distillation device for regeneration treatment at a temperature of 105° C., and fractionating to obtain a liquid mixture of water and organic waste gas in liquid form and a regenerated absorption liquid;

[0095] 4) The mass of the liquid form of the obtained organic waste gas is about 81g, and the water mixed with it after boiling for 30 minutes is about 17L. The cost-effectiveness of recycling the liquid components of the organic waste gas is low; after 50 minutes of absorption, distillation and regeneration absorption are required once. Each distillation is heated to boiling and boiled until the absorbed organic waste gas components are fully separated. It takes about 50 minutes. The system has high energy consumption, so it cannot be actually applied in engineering practice.

[0096] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for separating organic components in gas, characterized in that: include: Absorption purification: The gas containing organic components is subjected to absorption purification treatment using an absorption liquid with inclusion capacity to obtain the absorbed absorption liquid; Inclusion treatment: transporting the absorbed absorption liquid to an inclusion promotion device for inclusion promotion treatment to obtain the absorbed absorption liquid after inclusion; Repeated absorption and inclusion: The absorption liquid after inclusion is repeatedly absorbed, purified and included in turn.

2. The separation method according to claim 1, characterized in that In the repeated absorption and inclusion step, the absorption purification and inclusion treatment steps are repeated in sequence until the inclusion capacity of the absorption liquid is saturated; And / or, the inclusion promotion treatment comprises at least one of microwave, ultrasound, stirring, cooling and pressurizing; And / or, after the repeated absorption and inclusion step, the absorption liquid after repeated absorption and inclusion is regenerated to separate the organic components, and the absorption liquid after the regeneration treatment recovers the absorption and inclusion capacity and returns to the absorption and purification step for repeated use; optionally, the regeneration treatment includes distillation.

3. The separation method according to claim 1 or 2, characterized in that The absorption purification treatment time is 5-180min; And / or, the duration of the inclusion treatment is 5-360 min.

4. The separation method according to claim 1 or 2, characterized in that The absorption liquid with inclusion capacity comprises: 1-40 wt % inclusion agent, 0.1-20 wt % functional auxiliary agent and 40-99 wt % solvent.

5. The separation method according to claim 4, characterized in that The inclusion agent is cyclodextrin and its derivatives, preferably at least one of α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, methyl-β-cyclodextrin and cyclodextrin polymer; And / or, the functional additive includes at least one of a solubilizer, a cosolvent, a dispersant, an emulsifier, an antioxidant, an anti-yellowing agent, an anti-corrosion agent, and a defoaming agent; And / or, the solvent is water.

6. A system for separating organic components in gas, characterized in that: A method for separating organic components in gas according to any one of claims 1 to 5, comprising a gas-liquid absorption device and an inclusion promotion device which are interconnected to form a circulation loop; the gas-liquid absorption device is filled with an absorption liquid with inclusion capacity, and the inclusion promotion device is equipped with at least one of a microwave device, an ultrasonic device, a stirring device, and a cooling and pressurizing device.

7. The separation system according to claim 6, characterized in that The gas-liquid absorption device is a gas-liquid contact and mass transfer device, preferably at least one of a packed tower, a plate tower, a bubbling tower, a venturi tube, and a supergravity absorption tower.

8. The separation system according to claim 6 or 7, characterized in that: The outlet of the gas-liquid absorption device and / or the outlet of the inclusion promotion device is also connected to an absorption liquid regeneration separation device, and the absorption liquid outlet of the absorption liquid regeneration separation device is connected to the inlet of the gas-liquid absorption device.

9. The separation system according to claim 8, characterized in that The outlet of the inclusion promoting device is connected to the inlet of the gas-liquid absorption device through a first circulation pipeline, and the absorption liquid outlet of the absorption liquid regeneration separation device is connected to the inlet of the gas-liquid absorption device through a second circulation pipeline. Circulation pumps are provided on the first circulation pipeline and the second circulation pipeline to realize a small circulation of the absorption liquid in the gas-liquid absorption device and the inclusion promoting device, and a large circulation of the absorption liquid in the gas-liquid absorption device, the inclusion promoting device and the absorption liquid regeneration separation device.

10. The separation system according to claim 8 or 9, characterized in that: The absorption liquid regeneration and separation device includes atmospheric distillation equipment and / or reduced pressure distillation equipment.

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