Waste gas purification device for hydrogen peroxide and purification method thereof

Abstract

The invention discloses a waste gas purification device for hydrogen peroxide and a purification method of the waste gas purification device. The waste gas purification device comprises a condenser, an enrichment mechanism, a pressure swing adsorption mechanism and a gas recovery and storage mechanism, the condenser is provided with a medium flowing area used for allowing heat exchange media to flow, a cooling medium inlet is formed in the end, close to the top, of the medium flowing area, a cooling medium outlet is formed in the other end, close to the bottom, of the medium flowing area, and an inlet three-way valve and a first outlet three-way valve are installed on the top of the condenser. According to the waste gas purification device, aromatic hydrocarbon molecules in waste gas can be effectively removed, the effect of recovering oxygen and nitrogen is achieved, before the aromatic hydrocarbon molecules in the waste gas are adsorbed, the aromatic hydrocarbon molecules are introduced into the condenser and condensed to remove moisture in the waste gas, the water molecules are prevented from occupying active sites on an adsorption material, and the adsorption efficiency is improved. A competitive relationship between water molecules and aromatic hydrocarbon molecules on the adsorption material is prevented, and the adsorption quantity and the adsorption efficiency of the aromatic hydrocarbon molecules in subsequent adsorption are favorably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas purification, in particular to the separation of gas or steam, and specifically to a waste gas purification device for hydrogen peroxide and a purification method thereof. Background Art

[0002] Hydrogen peroxide is an inorganic compound with the chemical formula H2O2. Pure hydrogen peroxide is a light blue viscous liquid that can be miscible with water in any proportion. It is a strong oxidant. Its aqueous solution is commonly known as hydrogen peroxide and is a colorless and transparent liquid.

[0003] In the production process of hydrogen peroxide, especially when it is prepared by the anthraquinone method, the scenarios where waste gas is generated are mainly concentrated in the production stages such as hydrogenation and oxidation. In these stages, due to the participation of hydrogen and oxygen, and the recycling of working fluids (including heavy aromatics, trioctyl phosphate, etc.), waste gas mainly containing multiple gas components such as water vapor, oxygen, nitrogen and aromatic vapor will be generated.

[0004] The Chinese invention patent with publication number CN113368650B discloses a waste gas purification and recovery treatment device and method for hydrogen peroxide production, including a base, a condenser is installed on the top of the base, a control panel is installed at the middle position on the left side of the condenser, a pressure sensor is installed inside the condenser, and the pressure sensor is electrically connected to the control panel through a wire, a water vapor filter assembly is installed on the top of the condenser, an air charging mechanism is arranged on the right side of the condenser, and a storage mechanism is arranged on the surface of the air charging mechanism. It has the advantage of recovering oxygen and nitrogen in the waste gas, and solves the problem of directly discharging the waste gas after simple treatment, which wastes some recyclable gas.

[0005] The waste gas purification and recovery treatment device often only focuses on removing and recovering water vapor, oxygen and nitrogen in the waste gas, but the waste gas often contains aromatic molecules. These aromatic vapors not only pose a threat to the environment, but may also have adverse effects on the health of production personnel. The invention mostly relies on a single treatment method and lacks diversified and comprehensive treatment for different components and emission characteristics in the waste gas, thereby reducing the purification effect of the waste gas.

[0006] Therefore, it is necessary to improve the deficiencies in the prior art to solve the above problems. Summary of the invention

[0007] The present invention overcomes the deficiencies of the prior art and provides a waste gas purification device for hydrogen peroxide and a purification method thereof.

[0008] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a waste gas purification device for hydrogen peroxide, comprising: a condenser, an enrichment mechanism, a pressure swing adsorption mechanism and a gas recovery and storage mechanism; The condenser is provided with a medium flow area for providing a heat exchange medium flow, one end of the medium flow area close to the top is provided with a cooling medium inlet, and the other end close to the bottom is provided with a cooling medium outlet, and the top of the condenser is provided with an inlet three-way valve and a first outlet three-way valve; The two ends of the inlet three-way valve are respectively connected to the exhaust gas delivery pipe and the pressure swing adsorption mechanism, the two ends of the first outlet three-way valve are respectively connected to the enrichment mechanism and the gas recovery and storage mechanism, and the enrichment mechanism is connected to the pressure swing adsorption mechanism; The enrichment mechanism is used to increase the concentration of aromatic molecules in the exhaust gas after condensation, the pressure swing adsorption mechanism is used to adapt the pressure according to the concentration of aromatic molecules in the exhaust gas for adsorption filtration, and the gas recovery and storage mechanism is used to store oxygen and nitrogen recovered from the exhaust gas.

[0009] In a preferred embodiment of the present invention, the enrichment mechanism comprises: an ejector assembly and an enrichment tank connected in sequence; the ejector assembly comprises: a collecting pipe, a mixing pipe and a diffuser pipe arranged in sequence at one end of the collecting pipe; an ejector pipe for injecting nitrogen is fixed at the other end of the collecting pipe, and a connecting pipe is fixed on the side of the collecting pipe; The cross-sectional shapes of one end of the collecting pipe and the ejector pipe are both conical, and the cross-sectional shape of the diffuser pipe is a trumpet structure with a gradually expanding cross-section. One end of the mixing pipe is fixed to the conical end of the collecting pipe, and the other end is fixed to the end with a smaller diameter of the diffuser pipe. The conical end of the ejector pipe penetrates into the interior of the collecting pipe.

[0010] In a preferred embodiment of the present invention, the first outlet three-way valve is connected to the connecting pipe by a pipeline, and a first air pump and a gas pressure reducing valve are installed in sequence on the pipeline between the first outlet three-way valve and the connecting pipe, and the diffuser pipe is connected to the enrichment tank by a pipeline, and a one-way valve is installed on the pipeline between the diffuser pipe and the enrichment tank.

[0011] In a preferred embodiment of the present invention, a gas analyzer for detecting the concentration of aromatic hydrocarbon molecules in the gas is disposed on the side of the enrichment tank.

[0012] In a preferred embodiment of the present invention, the pressure swing adsorption mechanism includes: an activated carbon adsorption tower and a gas compressor; the input end of the gas compressor is connected to one end of the enrichment tank through a pipeline, and the output end is connected to one end of the activated carbon adsorption tower through a pipeline; a pressure gauge is installed on the activated carbon adsorption tower.

[0013] In a preferred embodiment of the present invention, the activated carbon adsorption tower is connected to the inlet three-way valve through a pipeline, and a second air pump is installed on the pipeline between the activated carbon adsorption tower and the inlet three-way valve.

[0014] In a preferred embodiment of the present invention, the gas recovery and storage mechanism includes: an oxygen storage tank, a nitrogen storage tank and a second outlet three-way valve; both ends of the second outlet three-way valve are connected to the oxygen storage tank and the nitrogen storage tank through pipelines, respectively, the first outlet three-way valve and the second outlet three-way valve are connected through a pipeline, and a third air pump is installed on the pipeline between the first outlet three-way valve and the second outlet three-way valve.

[0015] In a preferred embodiment of the present invention, it also includes: a condensate recovery mechanism, which includes: a recovery tank and a circulation pump; the input end of the circulation pump is connected to the bottom of the condenser through a pipeline, and the output end is connected to the recovery tank through a pipeline; a valve is installed on the pipeline between the circulation pump and the condenser.

[0016] The present invention provides a purification method for a waste gas purification device for hydrogen peroxide, comprising the following steps: S1. The waste gas from hydrogen peroxide production is fed into the condenser through the waste gas delivery pipe and the inlet three-way valve. The cooling medium is passed through the cooling medium inlet, the medium flow area and the cooling medium outlet to form a heat exchange loop, so that the condenser is cooled below 0°C, and the waste gas is condensed to remove moisture; S2, the exhaust gas after water removal is input into the enrichment mechanism through the first outlet three-way valve, and the concentration of aromatic hydrocarbon molecules in the exhaust gas is increased by the enrichment mechanism; S3. Adapt the pressure according to the concentration of aromatic molecules in the exhaust gas, input the exhaust gas into the pressure swing adsorption mechanism, and adsorb and filter the aromatic molecules; S4, input the filtered gas into the condenser through the inlet three-way valve, reduce the temperature of the condenser to between -183°C and -196°C, liquefy the oxygen in the gas, and input the nitrogen in the condenser into the gas recovery storage mechanism through the first outlet three-way valve; S5. After the recovery of nitrogen is completed, the temperature of the condenser is raised to above -183°C to gasify the oxygen in the condenser, and the oxygen in the condenser is input into the gas recovery storage mechanism through the first outlet three-way valve, thereby completing the purification of the exhaust gas.

[0017] In a preferred embodiment of the present invention, in the step S3, the adapted pressure is specifically: adapting the pressure value with the highest adsorption efficiency according to the concentration of aromatic molecules in the exhaust gas.

[0018] The present invention solves the defects existing in the background technology and has the following beneficial effects: (1) The present invention provides a waste gas purification device for hydrogen peroxide and a purification method thereof. By passing the waste gas in the production of hydrogen peroxide through a condenser, an enrichment mechanism, a pressure swing adsorption mechanism and a gas recovery and storage mechanism in sequence, the aromatic hydrocarbon molecules in the waste gas can be effectively removed, and the effects of recovering oxygen and nitrogen can be achieved respectively. Before the aromatic hydrocarbon molecules in the waste gas are adsorbed, the waste gas is first passed through a condenser, and the waste gas in the condenser is reduced to below 0°C under the cooperation of a cooling medium inlet and a cooling medium inlet, so that the moisture in the waste gas can be condensed and removed, and water molecules are prevented from occupying active sites on the adsorption material, and water molecules are prevented from competing with aromatic hydrocarbon molecules on the adsorption material, thereby reducing the interference of water molecules and helping to increase the adsorption amount and adsorption efficiency of aromatic hydrocarbon molecules in subsequent adsorption.

[0019] (2) In the present invention, the aromatic hydrocarbon molecules in the exhaust gas after condensation can be concentrated and their concentration in the gas phase can be increased through the cooperation of the first outlet three-way valve, the first air pump, the gas pressure reducing valve, the ejector assembly one-way valve and the enrichment tank, so as to avoid the aromatic hydrocarbon molecules after condensation treatment existing in the exhaust gas at a lower concentration, thereby reducing the contact opportunity between the subsequent adsorption material and the aromatic hydrocarbon molecules, resulting in a decrease in adsorption efficiency. In the subsequent pressure swing adsorption process, the contact opportunity between the adsorption material and the aromatic hydrocarbon molecules can be increased, which helps the adsorption material to adsorb more aromatic hydrocarbon molecules under limited capacity, thereby improving the separation effect and purity.

[0020] (3) In the present invention, the adsorption and separation of aromatics are achieved by adjusting the adaptive pressure when filtering aromatic molecules in the waste gas. The appropriate pressure can promote the diffusion and adsorption of aromatic molecules on the surface of activated carbon, so that the pressure swing adsorption process can be carried out more efficiently, and the adsorption cycle and desorption conditions can be optimized, which helps to improve the treatment efficiency and aromatic adsorption efficiency, thereby improving the overall waste gas purification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. Figure 1 It is a schematic diagram of the overall structure of a preferred embodiment of the present invention; Figure 2 It is a schematic diagram of the overall structure of the ejection assembly of a preferred embodiment of the present invention; In the figure: 1. condenser; 11. cooling medium inlet; 12. cooling medium outlet; 13. inlet three-way valve; 14. first outlet three-way valve; 2. enrichment mechanism; 21. enrichment tank; 22. collecting pipe; 23. mixing pipe; 24. diffuser; 25. ejector; 26. connecting pipe; 27. first air pump; 28. gas pressure reducing valve; 29. ​​one-way valve; 3. pressure swing adsorption mechanism; 31. activated carbon adsorption tower; 32. gas compressor; 33. pressure gauge; 34. second air pump; 4. gas recovery and storage mechanism; 41. oxygen storage tank; 42. nitrogen storage tank; 43. second outlet three-way valve; 44. third air pump; 5. gas analyzer; 6. recovery tank; 61. circulation pump; 62. valve. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0024] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, "multiple" means two or more.

[0025] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0026] like Figure 1 As shown, a waste gas purification device for hydrogen peroxide comprises: a condenser 1, an enrichment mechanism 2, a pressure swing adsorption mechanism 3 and a gas recovery storage mechanism 4; a medium flow area for providing a heat exchange medium flow is provided on the condenser 1, a cooling medium inlet 11 is installed at one end of the medium flow area close to the top, and a cooling medium outlet 12 is installed at the other end close to the bottom, and an inlet three-way valve 13 and a first outlet three-way valve 14 are installed on the top of the condenser 1; the two ends of the inlet three-way valve 13 are respectively connected to the waste gas conveying pipe and the pressure swing adsorption mechanism 3, and the two ends of the first outlet three-way valve 14 are respectively connected to the enrichment mechanism 2 and the gas recovery storage mechanism 4, and the enrichment mechanism 2 is connected to the pressure swing adsorption mechanism 3; the enrichment mechanism 2 is used to increase the concentration of aromatic molecules in the waste gas after condensation, the pressure swing adsorption mechanism 3 is used to adapt the pressure according to the concentration of aromatic molecules in the waste gas for adsorption and filtration, and the gas recovery storage mechanism 4 is used to store oxygen and nitrogen recovered from the waste gas.

[0027] It should be noted that the shape of the medium flow zone is preferably serpentine, which increases the contact area and improves the heat exchange effect. The cooling medium inlet 11, the medium flow zone and the cooling medium inlet 11 form a heat exchange circuit of the condenser 1. The cooling medium inlet 11 and the cooling medium inlet 11 are externally connected to the cooling medium temperature control and delivery equipment, which belongs to the prior art. Therefore, this application no longer explains the control method and structural principle in detail, and no detailed description is made here; the exhaust gas purification device can effectively remove the aromatic hydrocarbon molecules in the exhaust gas by passing the exhaust gas in the hydrogen peroxide production through the condenser 1, the enrichment mechanism 2, the pressure swing adsorption mechanism 3 and the gas recovery and storage mechanism 4 in sequence, and achieve recovery respectively. The effect of oxygen and nitrogen is achieved by first introducing the exhaust gas into the condenser 1 before adsorbing the aromatic molecules in the exhaust gas. By utilizing the cooling medium inlet 11 and the cooling medium temperature control and delivery equipment external to the cooling medium inlet 11, the cooling medium can form a heat exchange loop of the condenser 1 at the cooling medium inlet 11, the medium flow area and the cooling medium inlet 11, so that the exhaust gas in the condenser 1 drops below 0°C, and can condense and remove moisture in the exhaust gas, avoiding water molecules from occupying active sites on the adsorption material, and preventing water molecules from competing with aromatic molecules on the adsorption material, thereby reducing the interference of water molecules and helping to increase the adsorption amount and adsorption efficiency of aromatic molecules in subsequent adsorption.

[0028] like Figure 1 and Figure 2 As shown, in some embodiments, the enrichment mechanism 2 includes: an ejector assembly and an enrichment tank 21 connected in sequence; the ejector assembly includes: a collecting pipe 22, a mixing pipe 23 and a diffuser pipe 24 arranged in sequence at one end of the collecting pipe 22; an ejector pipe 25 for injecting nitrogen is fixed to the other end of the collecting pipe 22, and a connecting pipe 26 is fixed to the side of the collecting pipe 22; the cross-sectional shape of one end of the collecting pipe 22 and the ejector pipe 25 are both conical, and the cross-sectional shape of the diffuser pipe 24 is a trumpet structure with a gradually expanding cross-section, one end of the mixing pipe 23 is fixed to the conical end of the collecting pipe 22, and the other end is fixed to the end of the diffuser pipe 24 with a smaller diameter, and the conical end of the ejector pipe 25 passes through the interior of the collecting pipe 22.

[0029] It should be noted that the first outlet three-way valve 14 is connected to the connecting pipe 26 through a pipeline, and a first air pump 27 and a gas pressure reducing valve 28 are installed in sequence on the pipeline between the first outlet three-way valve 14 and the connecting pipe 26. The diffuser pipe 24 is connected to the enrichment tank 21 through a pipeline, and a one-way valve 29 is installed on the pipeline between the diffuser pipe 24 and the enrichment tank 21; the inner diameter of the mixing pipe 23, the inner diameter of the tapered end of the collecting pipe 22, the inner diameter of the smaller end of the diffuser pipe 24, and the inner diameter of the connecting pipe 26 are preferably 10-40 mm, and the inner diameter of the other end of the collecting pipe 22 and the diffuser pipe 24 are preferably 10-40 mm. The inner diameter of the end with the smaller diameter of the pressure pipe 24 is preferably 35-110 mm; one end of the ejector pipe 25 is externally connected to the nitrogen delivery equipment, and the first outlet three-way valve 14 is opened at the same time, the connection direction is switched from the condenser 1 to the connecting pipe 26, and the first air pump 27 is started to extract the waste gas after the moisture is removed from the condenser 1, and after the pressure is reduced by the gas pressure reducing valve 28, it enters the connecting pipe 26 at a lower pressure. At the same time, the external nitrogen delivery equipment delivers nitrogen to the ejector pipe 25 at a higher pressure, and the nitrogen in the ejector pipe 25 will flow out of the ejector pipe 25 at a higher speed. The conical end of the collecting pipe 22 is sprayed into the interior of the collecting pipe 22, and a low-pressure area is formed at the conical end of the ejector pipe 25. Since the exhaust gas entering the collecting pipe 22 through the connecting pipe 26 is in a relatively high-pressure state, the exhaust gas and the aromatic molecules therein are attracted by the low-pressure area and accelerated to be drawn into the nitrogen, and quickly enter the interior of the mixing pipe 23 through the conical end of the collecting pipe 22 through a flow channel with a successively reduced cross-sectional area, so that the nitrogen and the exhaust gas are mixed and transferred heat, mass, and at a uniform speed and pressure, and then enter the interior of the diffuser pipe 24 from the interior of the mixing pipe 23 and pass through the one-way valve 2 on the pipeline. 9. The aromatic molecules in the gas are rapidly and massively introduced and enriched in the enrichment tank 21, and the aromatic molecules in the exhaust gas after condensation can be concentrated to increase their concentration in the gas phase, thereby preventing the aromatic molecules after condensation from existing in the exhaust gas at a lower concentration, and reducing the contact opportunity between the subsequent adsorption material and the aromatic molecules, resulting in a decrease in adsorption efficiency. In the subsequent pressure swing adsorption process, the contact opportunity between the adsorption material and the aromatic molecules can be increased, which helps the adsorption material to adsorb more aromatic molecules under a limited capacity, thereby improving the separation effect and purity.

[0030] Specifically, according to the continuity equation in fluid mechanics, when a gas passes through a contracting or expanding pipe, the flow rate will change with the change in the cross-sectional area of ​​the pipe. When the pipe contracts, the flow rate of the gas will increase because the flow rate of the gas must be equal at any two points in the pipe. Bernoulli's equation describes the relationship between flow rate, pressure and fluid potential energy in an ideal fluid. When gas flows from a larger pipe into a part with a suddenly reduced diameter, the flow rate will increase and the pressure of the fluid will decrease. This pressure difference can drive the gas to flow out faster.

[0031] In some embodiments, a gas analyzer 5 for detecting the concentration of aromatic hydrocarbon molecules in the gas is disposed on the side of the enrichment tank 21 .

[0032] It should be noted that the gas analyzer 5 is used to directly measure the concentration of a specific component or multiple components in the gas. It is preferably an infrared gas analyzer 5. It uses the infrared absorption principle to detect the concentration of aromatic molecules by measuring the specific absorption band of infrared light by aromatic molecules. It can monitor the concentration of aromatic molecules in the gas in the enrichment tank 21 in real time, thereby providing the staff with the concentration data of aromatic molecules for subsequent adaptation of the adsorption pressure.

[0033] In some embodiments, the pressure swing adsorption mechanism 3 includes: an activated carbon adsorption tower 31 and a gas compressor 32; the input end of the gas compressor 32 is connected to one end of the enrichment tank 21 through a pipeline, and the output end is connected to one end of the activated carbon adsorption tower 31 through a pipeline; a pressure gauge 33 is installed on the activated carbon adsorption tower 31.

[0034] It should be noted that when the waste gas is subjected to pressure swing adsorption, the required adaptation pressure is determined according to the concentration of aromatic molecules in the waste gas, and the gas compressor 32 is started to reach the corresponding operating parameters (rotation speed, air intake, etc.) to control the pressure of the output gas. The gas compressor 32 extracts the waste gas in the enrichment tank 21 through the pipeline at the input end, and compresses the waste gas to reduce the volume and shorten the distance between molecules, thereby increasing the waste gas pressure. The waste gas is input into the activated carbon adsorption tower 31 through the pipeline at the output end, so that when the activated carbon adsorption tower 31 adsorbs aromatic molecules, it adapts to the corresponding adsorption pressure, thereby completing the adsorption of aromatic molecules. At the same time, the pressure gauge 33 on the activated carbon adsorption tower 31 is used to facilitate the staff to monitor the internal pressure value.

[0035] In some embodiments, the activated carbon adsorption tower 31 is connected to the inlet three-way valve 13 through a pipeline, and a second air pump 34 is installed on the pipeline between the activated carbon adsorption tower 31 and the inlet three-way valve 13; when the activated carbon adsorption tower 31 is adsorbing and filtering, the inlet three-way valve 13 is opened, and the connection direction is switched from the activated carbon adsorption tower 31 to the condenser 1, and the second air pump 34 is started to extract the adsorbed gas from the activated carbon adsorption tower 31, which can be transported to the condenser 1 through the pipeline therebetween, so as to facilitate the subsequent gas recovery treatment.

[0036] In some embodiments, the gas recovery storage mechanism 4 includes: an oxygen storage tank 41, a nitrogen storage tank 42 and a second outlet three-way valve 43; both ends of the second outlet three-way valve 43 are connected to the oxygen storage tank 41 and the nitrogen storage tank 42 through pipelines, respectively, the first outlet three-way valve 14 and the second outlet three-way valve 43 are connected through a pipeline, and a third air pump 44 is installed on the pipeline between the first outlet three-way valve 14 and the second outlet three-way valve 43.

[0037] It should be noted that, when the gas after adsorption and filtration is in the condenser 1 and the oxygen is liquefied, the first outlet three-way valve 14 is opened, and the connection direction is switched from the condenser 1 to the second outlet three-way valve 43. At the same time, the second outlet three-way valve 43 is opened, and the connection direction is switched from the first outlet three-way valve 14 to the nitrogen storage tank 42. The third air pump 44 on the pipeline between the first outlet three-way valve 14 and the second outlet three-way valve 43 is started to extract the nitrogen that is kept in a gaseous state and separated in the condenser 1. It can be transported to the nitrogen storage tank 42 through the pipeline between them for recovery. When the oxygen in the condenser 1 is re-gasified, the first outlet three-way valve 14 is opened, and the connection direction is switched from the condenser 1 to the second outlet three-way valve 43. At the same time, the second outlet three-way valve 43 is opened, and the connection direction is switched from the first outlet three-way valve 14 to the oxygen storage tank 41. The third air pump 44 is started to extract the oxygen in the condenser 1. It can be transported to the oxygen storage tank 41 through the pipeline between them for recovery, so that the recovery and storage of oxygen and nitrogen can be completed respectively.

[0038] In some embodiments, it also includes: a condensate recovery mechanism, which includes: a recovery tank 6 and a circulation pump 61; the input end of the circulation pump 61 is connected to the bottom of the condenser 1 through a pipeline, and the output end is connected to the recovery tank 6 through a pipeline; a valve 62 is installed on the pipeline between the circulation pump 61 and the condenser 1.

[0039] It should be noted that the types of valve 62 include but are not limited to one-way valve 29, flow valve, pneumatic valve, electric valve or stop valve, etc.; after the exhaust gas condensation or oxygen recovery is completed, the valve 62 installed on the pipeline between the circulation pump 61 and the condenser 1 is opened, the circulation pump 61 is started, the condensed water in the condenser 1 is pumped out, and transported to the inside of the recovery tank 6 through the output end of the circulation pump 61, thereby completing the recovery of the condensed water.

[0040] The present invention provides a purification method for a waste gas purification device for hydrogen peroxide, comprising the following steps: S1. The waste gas during the production of hydrogen peroxide is fed into the condenser 1 through the waste gas delivery pipe and the inlet three-way valve 13. The cooling medium is passed through the cooling medium inlet 11, the medium flow area and the cooling medium outlet 12 to form a heat exchange loop, so that the condenser 1 is cooled to below 0°C, and the waste gas is condensed to remove moisture; S2, the exhaust gas after water removal is input to the enrichment mechanism 2 through the first outlet three-way valve 14, and the concentration of aromatic molecules in the exhaust gas is increased by the enrichment mechanism 2; S3, adapting the pressure according to the concentration of aromatic molecules in the exhaust gas, inputting the exhaust gas into the pressure swing adsorption mechanism 3, and adsorbing and filtering the aromatic molecules; S4, input the filtered gas into the condenser 1 through the inlet three-way valve 13, so that the condenser 1 drops to between -183°C and -196°C, liquefies the oxygen in the gas, and inputs the nitrogen in the condenser 1 into the gas recovery storage mechanism 4 through the first outlet three-way valve 14; S5. After the recovery of nitrogen is completed, the temperature of the condenser 1 is raised to above -183°C, the oxygen in the condenser 1 is gasified, and the oxygen in the condenser 1 is input into the gas recovery storage mechanism 4 through the first outlet three-way valve 14, thereby completing the purification of the exhaust gas.

[0041] It should be noted that in step S3, the adaptation pressure is specifically: adapting the pressure value with the highest adsorption efficiency according to the concentration of aromatic molecules in the exhaust gas; in steps S4 and S5, the temperature change process of the condenser 1 is carried out under standard atmospheric pressure.

[0042] Specifically, the adaptation pressure is obtained by the following steps: A1, mixing the aromatic gas and the carrier gas to a concentration of c1, setting the adsorption pressure p1 in the adsorption column filled with adsorption material, passing the mixed gas of the aromatic gas and the carrier gas into the adsorption column, measuring the concentration change of the aromatic molecules before and after passing through the adsorption column, and calculating the adsorption amount k1; A2, concentration c1 remains unchanged, input pressure p2, and calculate the adsorption amount k2; ……; The concentration c1 remains unchanged, the pressure pn is input, and the adsorption amount kn is calculated; A3, adjusting the concentrations c1, c2, ..., cn of the mixture of the aromatic gas and the carrier gas, repeating the steps of S11 and S12, and obtaining the pressure and adsorption amount data at multiple concentrations; A4. Organize all the acquired concentration, pressure and adsorption data. For each pressure point, analyze the adsorption change trend under different concentrations to determine the adsorption saturation point. For each concentration point, analyze the adsorption efficiency under different pressures to determine the pressure value with the highest adsorption efficiency. A5. Use mathematical methods to construct a three-dimensional relationship model of concentration, pressure and adsorption efficiency. In the three-dimensional relationship model, identify the concentration and pressure area where the adsorption efficiency always remains at a high level, select representative concentration and pressure points in this area, and verify the stability of the adsorption efficiency for the selected concentration and pressure points; A6. According to the concentration of aromatic molecules in the exhaust gas, a three-dimensional relationship model is used to obtain the optimal adaptation pressure for adsorption efficiency.

[0043] It should be noted that in step A1, the carrier gas is preferably nitrogen, the adsorption material is preferably activated carbon, and the specific surface area, pore volume and pore size distribution of this activated carbon are consistent with those of the activated carbon in the activated carbon adsorption tower 31; in step A4, the arrangement is in the form of tables or charts, and the adsorption efficiency is expressed by the ratio of the adsorption amount to the initial concentration; in step A5, mathematical methods include but are not limited to interpolation and fitting, and the concentration and pressure points should cover different concentration ranges.

[0044] In this embodiment, it can cover gas samples including aromatic molecules of different concentrations and different pressure conditions, and can obtain the optimal pressure at each concentration, and construct the relationship between concentration, pressure and adsorption efficiency, which can be applied to the adsorption treatment of aromatic molecules in different exhaust gases. Then, according to the concentration of aromatic molecules, the adaptation pressure with the best adsorption efficiency can be obtained, so that the difference in the adsorption capacity of activated carbon for aromatic molecules under different pressures can be utilized to achieve the adsorption and separation of aromatics by adjusting the adaptation pressure. Appropriate pressure can promote the diffusion and adsorption of aromatic molecules on the surface of activated carbon, so that the pressure swing adsorption process can be carried out more efficiently, and the adsorption cycle and desorption conditions can be optimized, which helps to improve the treatment efficiency and aromatic adsorption efficiency, thereby improving the overall exhaust gas purification effect.

[0045] The above is based on the ideal embodiment of the present invention. Through the above description, it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0046] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A waste gas purification device for hydrogen peroxide, characterized in that: include: Condenser, enrichment mechanism, pressure swing adsorption mechanism and gas recovery and storage mechanism; The condenser is provided with a medium flow area for providing a heat exchange medium flow, one end of the medium flow area close to the top is provided with a cooling medium inlet, and the other end close to the bottom is provided with a cooling medium outlet, and the top of the condenser is provided with an inlet three-way valve and a first outlet three-way valve; The two ends of the inlet three-way valve are respectively connected to the exhaust gas delivery pipe and the pressure swing adsorption mechanism, the two ends of the first outlet three-way valve are respectively connected to the enrichment mechanism and the gas recovery and storage mechanism, and the enrichment mechanism is connected to the pressure swing adsorption mechanism; The enrichment mechanism is used to increase the concentration of aromatic molecules in the exhaust gas after condensation, the pressure swing adsorption mechanism is used to adapt the pressure according to the concentration of aromatic molecules in the exhaust gas for adsorption filtration, and the gas recovery and storage mechanism is used to store oxygen and nitrogen recovered from the exhaust gas.

2. The exhaust gas purification device for hydrogen peroxide according to claim 1, characterized in that: The enrichment mechanism comprises: an ejector assembly and an enrichment tank connected in sequence; the ejector assembly comprises: a collecting pipe, a mixing pipe and a diffuser pipe arranged in sequence at one end of the collecting pipe; an ejector pipe for injecting nitrogen is fixed at the other end of the collecting pipe, and a connecting pipe is fixed on the side of the collecting pipe; The cross-sectional shapes of one end of the collecting pipe and the ejector pipe are both conical, and the cross-sectional shape of the diffuser pipe is a trumpet structure with a gradually expanding cross-section. One end of the mixing pipe is fixed to the conical end of the collecting pipe, and the other end is fixed to the end with a smaller diameter of the diffuser pipe. The conical end of the ejector pipe penetrates into the interior of the collecting pipe.

3. The exhaust gas purification device for hydrogen peroxide according to claim 2, characterized in that: The first outlet three-way valve is connected to the connecting pipe through a pipeline, and a first air pump and a gas pressure reducing valve are installed in sequence on the pipeline between the first outlet three-way valve and the connecting pipe. The diffuser pipe is connected to the enrichment tank through a pipeline, and a one-way valve is installed on the pipeline between the diffuser pipe and the enrichment tank.

4. The exhaust gas purification device for hydrogen peroxide according to claim 2, characterized in that: A gas analyzer for detecting the concentration of aromatic hydrocarbon molecules in the gas is arranged on the side of the enrichment tank.

5. The exhaust gas purification device for hydrogen peroxide according to claim 2, characterized in that: The pressure swing adsorption mechanism includes: an activated carbon adsorption tower and a gas compressor; the input end of the gas compressor is connected to one end of the enrichment tank through a pipeline, and the output end is connected to one end of the activated carbon adsorption tower through a pipeline; a pressure gauge is installed on the activated carbon adsorption tower.

6. The exhaust gas purification device for hydrogen peroxide according to claim 5, characterized in that: The activated carbon adsorption tower is connected to the inlet three-way valve through a pipeline, and a second air pump is installed on the pipeline between the activated carbon adsorption tower and the inlet three-way valve.

7. The exhaust gas purification device for hydrogen peroxide according to claim 1, characterized in that: The gas recovery and storage mechanism includes: an oxygen storage tank, a nitrogen storage tank and a second outlet three-way valve; both ends of the second outlet three-way valve are connected to the oxygen storage tank and the nitrogen storage tank through pipelines, respectively, the first outlet three-way valve and the second outlet three-way valve are connected through a pipeline, and a third air pump is installed on the pipeline between the first outlet three-way valve and the second outlet three-way valve.

8. The exhaust gas purification device for hydrogen peroxide according to claim 1, characterized in that: Also includes: A condensed water recovery mechanism, the condensed water recovery mechanism comprising: a recovery tank and a circulation pump; The input end of the circulation pump is connected to the bottom of the condenser through a pipeline, and the output end is connected to the recovery tank through a pipeline; a valve is installed on the pipeline between the circulation pump and the condenser.

9. A purification method for a waste gas purification device for hydrogen peroxide according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. The waste gas from hydrogen peroxide production is fed into the condenser through the waste gas delivery pipe and the inlet three-way valve. The cooling medium is passed through the cooling medium inlet, the medium flow area and the cooling medium outlet to form a heat exchange loop, so that the condenser is cooled below 0°C, and the waste gas is condensed to remove moisture; S2, the exhaust gas after water removal is input into the enrichment mechanism through the first outlet three-way valve, and the concentration of aromatic hydrocarbon molecules in the exhaust gas is increased by the enrichment mechanism; S3. Adapt the pressure according to the concentration of aromatic molecules in the exhaust gas, input the exhaust gas into the pressure swing adsorption mechanism, and adsorb and filter the aromatic molecules; S4, input the filtered gas into the condenser through the inlet three-way valve, reduce the temperature of the condenser to between -183°C and -196°C, liquefy the oxygen in the gas, and input the nitrogen in the condenser into the gas recovery storage mechanism through the first outlet three-way valve; S5. After the recovery of nitrogen is completed, the temperature of the condenser is raised to above -183°C to gasify the oxygen in the condenser, and the oxygen in the condenser is input into the gas recovery storage mechanism through the first outlet three-way valve, thereby completing the purification of the exhaust gas.

10. The purification method for a waste gas purification device for hydrogen peroxide according to claim 9, characterized in that: In the step S3, the adapted pressure is specifically: adapting the pressure value with the highest adsorption efficiency according to the concentration of aromatic molecules in the exhaust gas.

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