Hybrid acid mist absorption device

Abstract

This utility model discloses a hybrid acid mist absorption device, belonging to the field of acid gas treatment. It includes a cylindrical body, inside which a Pall ring packing layer and a multi-layer MOF membrane assembly are arranged from top to bottom. The MOF membrane types in the multi-layer MOF membrane assembly, from top to bottom, are ZIF-8, UiO-66-NH2, and Mg-MOF-74. Acid mist flows from top to bottom within the cylindrical body. The Pall ring packing layer uses DN25 plastic Pall rings. The thickness of each membrane layer in the multi-layer MOF membrane assembly is 1 cm, and the spacing between membranes is 20 cm. By increasing the Pall ring packing layer, a large contact area is provided, significantly improving the contact time and contact area, achieving the aggregation and condensation of acid mist gas. Combined with the high specific surface area and adjustable pore structure of the MOF membrane itself, the adsorption efficiency is effectively improved. It treats acid mist through physical adsorption rather than neutralization reaction, without generating saline wastewater, eliminating the need for waste liquid collection, storage, neutralization to meet standards, or outsourced treatment, thus avoiding secondary pollution that may occur during waste liquid treatment at the source.

Description

Technical Field

[0001] This utility model belongs to the field of acid gas treatment technology, specifically relating to a mixed-type acid mist absorption device. Background Technology

[0002] In industrial production, chemical production, metal surface treatment, laboratory ventilation, battery manufacturing, electronics industry, some flue gas treatment, and incinerator exhaust gas treatment scenarios continuously generate mixed acid mists containing various components such as hydrochloric acid, sulfuric acid, and nitric acid. Direct emission of these mixed acid mists not only pollutes the atmosphere and disrupts the ecological balance, but also corrodes factory equipment and buildings, shortening equipment lifespan. Furthermore, they can harm human health through inhalation and skin contact, causing respiratory diseases, skin burns, and other problems. Therefore, they must be effectively treated before being released.

[0003] The neutralization-type acid mist absorption devices widely used in the industry can introduce acid mist into alkaline liquid to generate salts and water through acid-base neutralization reaction to achieve purification. However, they have significant drawbacks. On the one hand, due to the lack of structural design to expand the contact area and extend the contact time, the static absorption efficiency is low and the treatment capacity is limited. On the other hand, if the alkaline solution is not replaced in time after consumption, it is easy to cause acid mist leakage. In addition, the large amount of saline wastewater generated by the reaction requires additional investment in collection and treatment, and there is also a risk of secondary pollution. Utility Model Content

[0004] The purpose of this invention is to provide a hybrid acid mist absorption device to solve the problems of low static absorption efficiency, limited processing capacity, acid mist leakage caused by failure to replace alkali solution in time, and the need for additional treatment of the generated saline wastewater.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a hybrid acid mist absorption device, comprising a cylinder, wherein a Pall ring packing layer and a multi-layer MOF membrane assembly are arranged inside the cylinder from top to bottom, and the MOF membrane types of the multi-layer MOF membrane assembly from top to bottom are ZIF-8, UiO-66-NH2, and Mg-MOF-74, and the acid mist flows from top to bottom inside the cylinder.

[0006] Furthermore, the Pall ring packing layer is made of DN25 plastic Pall rings.

[0007] Furthermore, the thickness of each layer in the multilayer MOF membrane assembly is 1 cm, and the spacing between the membrane assemblies is 20 cm.

[0008] Furthermore, the cylinder is cylindrical and made of transparent plexiglass.

[0009] Furthermore, a colorimeter is installed outside the cylinder at the multilayer MOF membrane assembly.

[0010] Furthermore, the interior of the cylinder is provided with an arc-shaped guide plate at the acid mist inlet, which can guide the acid mist to flow in all directions along the guide plate.

[0011] Furthermore, a drain outlet is provided at the bottom of the cylinder, which is used to discharge non-acidic wastewater that has been condensed after the acid mist is adsorbed and filtered by the membrane module.

[0012] Furthermore, an acid mist detector is installed at the sewage outlet.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] This hybrid acid mist absorption device provides a huge contact area by adding a Pall ring packing layer, which significantly improves the contact time and contact area, enabling the aggregation and condensation of acid mist gas. Combined with the high specific surface area and adjustable pore structure of the MOF membrane itself, the adsorption efficiency is effectively improved. It treats acid mist by physical adsorption rather than neutralization reaction, and does not produce saline wastewater. It eliminates the need for waste liquid collection, storage, neutralization to meet standards or outsourced treatment, thus avoiding secondary pollution that may occur during waste liquid treatment from the source.

[0015] This hybrid acid mist absorption device employs a multi-layer MOF membrane module with a layered design, consisting of ZIF-8, UiO-66-NH2, and Mg-MOF-74 membranes from top to bottom. These membranes can specifically absorb different types of acid mist, such as hydrochloric acid, sulfuric acid, and nitric acid. Through internal size sieving and electrostatic synergy, combined with specific bonds on the MOF ligands, the device can precisely react with acid mist components, significantly enhancing adsorption selectivity and avoiding ineffective adsorption.

[0016] This hybrid acid mist absorption device employs a dual intelligent monitoring system comprised of a colorimeter and an acid mist detector. The colorimeter visually indicates the adsorption saturation state through changes in the membrane's color, while the acid mist detector monitors the outlet gas concentration in real time. The data from both instruments are cross-validated to prevent false alarms from a single instrument. An alarm can accurately guide membrane replacement, reducing manual inspection costs. Furthermore, if the concentration exceeds the limit, the system can be activated to stop mist intake, eliminating potential safety hazards. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a mixed-type acid mist absorption device.

[0018] In the diagram: 1. Cylinder; 2. Pall ring packing layer; 3. Multilayer MOF membrane module; 4. Acid mist inlet; 5. Colorimeter; 6. Acid mist detector; 7. Drain outlet; 8. Arc-shaped guide plate. Detailed Implementation

[0019] The present invention will be further described below with reference to the embodiments.

[0020] The following embodiments are used to illustrate the present invention, but should not be used to limit the scope of protection of the present invention. The conditions in the embodiments can be further adjusted according to specific conditions, and simple improvements to the method of the present invention under the premise of the concept of the present invention are all within the scope of protection claimed by the present invention.

[0021] Please see Figure 1 This utility model provides a mixed-type acid mist absorption device, comprising:

[0022] Cylinder 1: Cylinder 1 is cylindrical and provides the core reaction space. It can be made of transparent plexiglass.

[0023] Pall ring packing layer 2: The interior of cylinder 1 is filled with Pall rings, which significantly increases the contact area between acidic gas and the packing, improving the condensation and adhesion effect of acid mist gas on the packing surface. The high porosity also ensures sufficient gas passage and reduces gas flow resistance. The packing size is usually selected based on the cylinder diameter of cylinder 1. Since D / d (cylinder diameter / nominal packing diameter) > 10 can prevent wall flow effects, DN25 plastic Pall rings can be selected. Their high porosity, typically between 0.85 and 0.9, ensures very unobstructed gas passage.

[0024] Multilayer MOF membrane module 3: Located in the middle of the inner cavity of cylinder 1, below the Pall ring packing layer 2, it forms the main working part of the acid mist absorber together with the Pall ring packing layer 2. Each membrane layer is 1cm thick, and the membrane modules are spaced 20cm apart to ensure uniform airflow distribution, reduce pressure drop, and prevent clogging. Due to the large specific surface area of ​​the packing, the downward-flowing exhaust gas comes into full contact with the multilayer MOF membrane module 3. Acid mist components (H... + ,Cl - SO4 2- ,F - By using internal size sieving and electrostatic synergy, the pore size of the membrane module can be controlled to different sizes. Through different bonds on the MOF ligands, it can react with different acid mists, thus enhancing selective adsorption. From top to bottom, the MOF membrane types are ZIF-8 (absorbing hydrochloric acid mist), iO-66-NH2 (absorbing sulfuric acid mist), and Mg-MOF-74 (absorbing nitric acid mist).

[0025] Each layer of MOF membrane packing is integrated into an independent tray. Four PTFE pulleys are installed at the bottom of the tray, and two lifting handles are provided on the side wall of the tray. A sealing groove (filled with silicone rubber sealing gasket) is reserved to fit tightly with the flange face of the tower body to prevent acid mist leakage (leakage rate <0.1%), so that each layer of MOF membrane can be pulled out of the cylinder 1.

[0026] Acid mist inlet 4: Located at the top of cylinder 1, it guides acid mist-containing waste gas (HCl, H2SO4, HNO3, HF, etc.) into cylinder 1. The acid mist adopts an upward-in, downward-outflow flow pattern, which allows for full contact between the acid mist and the membrane module, ensuring no acidic droplets remain after absorption and purification. In contrast, if a downward-in, upward-outflow method is used, acidic droplets tend to accumulate at the bottom of the equipment, requiring regular manual venting, which not only increases maintenance costs but also poses a risk of personnel injury from acid contact.

[0027] Colorimeter 5: Located on one side of cylinder 1 and flush with multilayer MOF membrane 3, it detects the color difference change after multilayer MOF membrane 3 absorbs acid mist and has an alarm function.

[0028] Acid mist detector 6: Located near the sewage outlet 7, it monitors the concentration of acid mist in the purified gas in real time.

[0029] Sewage outlet 7: Located at the bottom of cylinder 1, it is used to discharge non-acidic wastewater that has been condensed after acid mist adsorption and filtration by the membrane module.

[0030] Arc-shaped guide plate 8: The arc-shaped guide plate 8 is set at the acid mist inlet 4 inside the cylinder 1, so that the acid mist flows from the arc-shaped guide plate 8 to the surrounding area, avoiding the problem of large concentration difference between the middle and the surrounding area of ​​the acid mist inside the cylinder 1.

[0031] The working principle and usage process of this utility model are as follows: Acid mist-containing waste gas enters the cylinder 1 through the top acid mist inlet 4; the waste gas flows downward from all sides of the arc-shaped guide plate 8, and the acid mist changes from a concentrated state to a uniformly distributed planar distribution through the Pall ring packing layer 2; on the huge specific surface area of ​​the packing, the downward-flowing waste gas comes into full contact with the MOF membrane module 3. Acid mist component (H + ,Cl - SO4 2- ,F - By using the size sieving and electrostatic synergy within the membrane module, the pore size of the membrane module can be controlled to different sizes. Through different base bonds on the MOF ligand, it can react with different acid mists to enhance selective adsorption.

[0032] After being thoroughly purified by the packing layer 2 and the multi-layer MOF membrane module 3, the gas is discharged from the bottom drain port 7 after being monitored by the acid mist monitor 6. The colorimeter 5 detects the color change ΔE of the multi-layer MOF membrane module 3, which is greater than 5.0, to visually determine the adsorption saturation state. The acid mist monitor 6 monitors the outlet gas concentration in real time and cross-validates the data with the colorimeter 5 to avoid false alarms from a single instrument.

[0033] The colorimeter 5, paired with the acid mist detector 6, provides dual intelligent detection. When the membrane module fails, the colorimeter 5 alarms, accurately guiding replacement and reducing manual inspection costs. The acid mist detector 6 can be set with a secondary alarm threshold (e.g., concentration > 10 ppm), triggering a system-wide shutdown of acid mist intake to ensure safe operation.

[0034] Eliminating the generation of acidic waste liquid avoids the generation of saline wastewater (such as NaCl solution) due to neutralization reactions, saving the trouble and cost of waste liquid collection, storage, neutralization to meet standards or outsourcing treatment, and eliminating the risk of secondary pollution that may be caused by the waste liquid treatment process itself.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A hybrid acid mist absorption device characterized by: The cylinder (1) includes a Pall ring packing layer (2) and a multi-layer MOF membrane assembly (3) arranged from top to bottom inside the cylinder (1). The MOF membrane types of the multi-layer MOF membrane assembly (3) are ZIF-8, UiO-66-NH2 and Mg-MOF-74 from top to bottom. Acid mist flows from top to bottom inside the cylinder (1).

2. A hybrid acid mist absorption device according to claim 1, characterized in that: The Pall ring packing layer (2) is made of DN25 plastic Pall rings.

3. A hybrid acid mist absorption device according to claim 1, characterized in that: The thickness of each layer in the multilayer MOF membrane group (3) is 1 cm, and the interval between membrane groups is 20 cm.

4. The hybrid acid mist absorption device of claim 1, wherein: The cylinder (1) is cylindrical and made of transparent organic glass.

5. The hybrid acid mist absorption device of claim 1, wherein: A colorimeter (5) is installed outside the cylinder (1) at the multilayer MOF membrane assembly (3).

6. A hybrid acid mist absorption device according to claim 1, characterized in that: An arc-shaped guide plate (8) is provided at the acid mist inlet (4) of the cylinder (1), and the arc-shaped guide plate (8) can guide the acid mist to flow in all directions along the guide plate.

7. The hybrid acid mist absorption device of claim 1, wherein: The bottom of the cylinder (1) is provided with a drain outlet (7), which is used to discharge non-acidic wastewater that has been condensed after the acid mist is adsorbed and filtered by the membrane module.

8. A hybrid acid mist absorption device according to claim 7, characterized in that: An acid mist detector (6) is installed at the sewage outlet (7).

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