CN110016814B - Antibacterial asymmetric total heat exchange membrane, total heat exchange core and total heat exchanger - Google Patents
Antibacterial asymmetric total heat exchange membrane, total heat exchange core and total heat exchanger Download PDFInfo
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- CN110016814B CN110016814B CN201910304606.7A CN201910304606A CN110016814B CN 110016814 B CN110016814 B CN 110016814B CN 201910304606 A CN201910304606 A CN 201910304606A CN 110016814 B CN110016814 B CN 110016814B
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Abstract
The invention provides an antibacterial asymmetric total heat exchange membrane, a total heat exchange machine core and a total heat exchanger. Antibacterial asymmetric total heat exchange membrane: loading an antibacterial agent on the porous heat-conducting filler to obtain the antibacterial porous heat-conducting filler; dissolving a high molecular polymer and a hygroscopic metal salt in a solvent to obtain a hydrophilic polymer solution, and mixing the antibacterial porous heat-conducting filler, a pore-forming agent and the hydrophilic polymer solution to obtain a membrane casting solution; coating the casting film liquid on non-woven fabric fixed on a glass plate, and soaking the non-woven fabric in water to react to obtain a base film; and (3) soaking the base membrane in water, and drying to obtain the antibacterial asymmetric total heat exchange membrane. The total heat exchange core is made of an antibacterial asymmetric total heat exchange membrane. Total heat exchanger, including total heat exchanger core. The antibacterial asymmetric total heat exchange membrane, the total heat exchange machine core and the total heat exchange machine have the advantages of high heat conductivity and moisture permeability, simple process, low cost, good antibacterial and mildew-proof effects, capability of avoiding secondary pollution and long service life.
Description
Technical Field
The invention relates to the field of total heat exchange, in particular to an antibacterial asymmetric total heat exchange membrane, a total heat exchange core and a total heat exchanger.
Background
With the enhancement of environmental awareness and the improvement of living standard of people, the requirement on indoor air quality is higher and higher. Fresh air circulation is an effective and economic method for improving indoor air quality, however, the energy consumption of the air conditioner is increased sharply due to the large fresh air ratio, the energy consumption for processing fresh air accounts for 20% -40% of the total energy consumption of the air conditioner, and the ratio is even larger in hot and humid summer in south. In order to effectively save energy, researchers continuously seek a low-energy-consumption fresh air heat and humidity recovery method.
The total heat exchanger has higher energy recovery efficiency, is a key technology of total heat recovery, and can well relieve and improve the contradiction among the comfort of indoor air quality, the thermal comfort and high energy consumption. The prior rotary wheel type total heat exchanger used earlier in the market of the total heat exchanger can simultaneously recover sensible heat and latent heat, has higher efficiency, but has the defects of high manufacturing cost of a rotary wheel, moving parts, poor reliability, easy mutual doping of fresh air and exhaust air and the like, and limits the popularization and application of the rotary wheel type total heat exchanger. Another heat pump type total heat exchanger needs to be equipped with a series of equipment such as a compressor, a condenser, an evaporator, etc. when in use, both the power consumption and the investment cost are high, and therefore, the development and the application are limited. With the development of membrane technology, the technology of heat and moisture recovery by using membranes has attracted more and more attention.
The existing membrane heat exchanger has the problems of small flow, poor thermal conductivity of thick membrane layer, low efficiency and the like, and can only recover sensible heat part and cannot carry out total heat recovery. And the membranes used in the prior art have no antibacterial and mildewproof effects, so that moist air in the air easily makes the surfaces of the membranes become hotbeds for breeding bacteria and grow mildews in the long-term use process, the service life of the membranes is shortened, and the secondary pollution of the air is easily caused.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The first purpose of the invention is to provide an antibacterial asymmetric total heat exchange membrane which has the advantages of good heat conductivity, high moisture permeability, simple process, low cost, good antibacterial and mildewproof effects, secondary pollution prevention and long service life.
The second purpose of the invention is to provide a total heat exchanger core which is prepared by using the antibacterial asymmetric total heat exchange membrane, and the total heat exchanger core has the advantages of good heat conductivity, high moisture permeability, good antibacterial and mildewproof effects and long service life.
A third object of the invention is to provide a total heat exchanger comprising the total heat exchanger core.
In order to achieve the purpose of the invention, the following technical scheme is adopted:
an antibacterial asymmetric total heat exchange membrane is prepared by the following steps:
A. loading an antibacterial agent on the porous heat-conducting filler to obtain the antibacterial porous heat-conducting filler;
B. dissolving a high molecular polymer and hygroscopic metal salt in a solvent to prepare a hydrophilic polymer solution, then mixing the antibacterial porous heat-conducting filler and the pore-forming agent with the hydrophilic polymer solution, heating, stirring and standing to obtain a membrane casting solution;
C. coating the film casting solution on non-woven fabric fixed on a glass plate, then immersing the non-woven fabric in water, and carrying out phase inversion reaction to obtain a base film; and taking out the base membrane, soaking the base membrane in water, and drying to obtain the antibacterial asymmetric total heat exchange membrane.
The porous material with the heat conduction function is selected as the heat conduction filler, so that the hole blockage of the heat conduction filler can be avoided, and meanwhile, the heat conduction material has a high specific surface area and a developed gap structure, so that the pore size distribution of the membrane material can be greatly improved, and the heat conduction performance of the membrane can be greatly improved. The antibacterial agent is loaded by taking the porous heat-conducting filler as a carrier, so that the total heat exchange membrane has an antibacterial effect while exerting heat-conducting performance. Compared with the traditional preparation method, the preparation process is simplified, the equipment is simplified, and the cost is reduced. The mechanical property of the membrane is effectively improved by adding the high molecular polymer, the hygroscopic metal salt and the pore-forming agent, so that the strength of the membrane is greatly improved, and meanwhile, the moisture permeation efficiency of the membrane is improved by 90-150 percent compared with that of the traditional composite membrane, thereby improving the enthalpy exchange efficiency of the membrane.
Preferably, the porous heat-conducting filler is one or more of carbon nano tubes, activated carbon and activated carbon fibers, and the antibacterial agent is a mixture of one or more of compounds containing silver ions, copper ions or zinc ions; preferably, the iron content of the carbon nano tube is 3-10 wt%, the iron content of the activated carbon and the activated carbon fiber is 8-20 wt%, and the dosage of the antibacterial agent is 0.5-1% of the weight of the porous heat-conducting filler.
Under the condition of coexistence with the hydrophilic polymer, the carbon nano tube, the activated carbon and the activated carbon fiber are adopted, and particularly the carbon nano tube, the activated carbon and the activated carbon fiber with high iron content are adopted, so that the heat conductivity coefficient of the membrane can be greatly improved. Compounds containing silver ions, copper ions or zinc ions such as silver nitrate, copper sulfate, copper chloride, zinc nitrate, zinc sulfate, etc.
In particular embodiments, the iron content of the carbon nanotubes may be any value between 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, and 3-10 wt%; the iron content of the activated carbon and activated carbon fibers may be any value between 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 14 wt%, 15 wt%, 16 wt%, 18 wt%, 19 wt%, 20 wt%, and 8-20 wt%; the antimicrobial agent may be used in an amount of 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, and any value between 0.5 and 1% by weight of the porous heat conductive filler.
Preferably, the loading process is as follows:
and adding the antibacterial agent into water to be fully dissolved, spraying the antibacterial agent into the porous heat-conducting filler, standing, and calcining at the temperature of 300-500 ℃ for 30-40min to obtain the antibacterial porous heat-conducting filler.
Meanwhile, the high-temperature treatment is carried out in the combination process of the heat conduction material and the antibacterial agent, so that the antibacterial agent is not separated out in the soaking process and the like. The antibacterial agent is loaded by spraying instead of soaking, so that the loading is more uniform, the consumption of the antibacterial agent and water is saved, and unnecessary waste is avoided. The amount of water used here is determined by the water capacity Q1 of the porous heat-conducting filler and the amount W1 of the porous heat-conducting filler, and the amount of water used is equal to the water capacity Q1 and the amount W1 of the porous heat-conducting filler. The water capacity of the porous heat-conducting filler can be calculated to accurately grasp the adsorption amount of the porous heat-conducting filler to the aqueous solution, and the antibacterial agent with a certain concentration is configured according to the adsorption capacity, so that all the configured solution can be adsorbed. Compared with an equal-volume impregnation method, the method saves water consumption, avoids the waste of the antibacterial agent, and simultaneously does not discharge and waste the residual antibacterial agent solution.
Preferably, the high molecular polymer is one of cellulose acetate and hydroxypropyl cellulose, the hygroscopic metal salt is one of lithium chloride, calcium chloride, sodium chloride, potassium chloride and magnesium chloride, the solvent is an acetic acid or formic acid aqueous solution with a mass fraction of 10-60%, and the pore-forming agent is polyvinyl alcohol or polyvinylpyrrolidone; preferably, the pore-foaming agent is polyvinyl alcohol-2000, and in the hydrophilic polymer solution, the mass percentage of the high molecular polymer is 10-25%, and the mass ratio percentage of the hygroscopic metal salt is 1.5-15%.
The optimization of the types and the use amounts of the high molecular polymer, the hygroscopic metal salt, the solvent and the pore-foaming agent is favorable for enhancing the water absorption performance and the forming performance of the casting solution and improving the enthalpy exchange efficiency.
In an alternative embodiment, the mass fraction of the aqueous acetic acid or formic acid solution may be any value between 10%, 20%, 30%, 40%, 50%, 60%, and 10-60%; the mass percentage of the high molecular polymer in the hydrophilic polymer solution may be any value between 10%, 15%, 20%, 25%, and 10 to 25%, and the mass percentage of the hygroscopic metal salt may be any value between 1.5%, 2.0%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, and 1.5 to 15%.
More preferably, the addition amount of the antibacterial porous heat-conducting filler is 1-10 wt% of the hydrophilic polymer solution, and the addition amount of the pore-forming agent is 0.5-2 wt% of the hydrophilic polymer solution.
In an alternative embodiment, the antibacterial porous heat-conductive filler is added in an amount of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10% and any value between 1 and 10 wt% of the hydrophilic polymer solution; the amount of porogen added is any value between 0.5%, 1.0%, 1.5%, 2.0% and 0.5-2 wt% of the hydrophilic polymer solution.
Further preferably, the heating temperature is 40-80 ℃, the heating time is 4-6h, the standing is carried out at normal temperature, and the standing time is 6-12 h.
Preferably, the non-woven fabric is one of terylene, polypropylene and acrylic; the thickness of the casting solution coated on the non-woven fabric is 80-110 μm.
In one embodiment, the thickness of the casting solution coated on the non-woven fabric may be any value between 80 μm, 90 μm, 100 μm, 110 μm, and 80-110 μm.
Optionally, the soaking time is 12-36 h; the drying temperature is 60-80 ℃ and the drying time is 2-4 h.
The total heat exchanger core is prepared by using the antibacterial asymmetric total heat exchange membrane.
The total heat exchanger comprises the total heat exchanger core.
Compared with the prior art, the invention has the beneficial effects that:
(1) the film has high strength, good thermal conductivity and high moisture permeability;
(2) the process is simple and the cost is low;
(3) has the effects of antibiosis and mildew prevention, and avoids secondary pollution;
(4) the service life is long.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Example 1
100g of carbon nanotubes having an iron content of 3 wt% were weighed and tested for a water capacity of 70%. 70g (100g 70%) of deionized water was weighed, 0.5g (100g 0.5%) of silver nitrate was added thereto, and the mixture was stirred sufficiently to form a silver nitrate solution, which was uniformly sprayed on the carbon nanotubes, and left to stand for 6 hours. Then calcining the mixture for 30min at the temperature of 400 ℃ to obtain the antibacterial porous heat-conducting filler.
Measuring 500ml of 50 mass percent acetic acid aqueous solution, adding cellulose acetate and lithium chloride into the aqueous solution to prepare a hydrophilic polymer solution, and controlling the mass percent of the cellulose acetate to be 25% and the mass percent of the lithium chloride to be 1.5% in the hydrophilic polymer solution; then adding antibacterial porous heat-conducting filler and polyethylene glycol-2000, controlling the addition of the antibacterial porous heat-conducting filler to be 10 wt% of the hydrophilic polymer solution, and controlling the addition of the polyethylene glycol-2000 to be 0.5 wt% of the hydrophilic polymer solution; fully stirring and reacting for 5 hours in a water bath kettle at 60 ℃, and standing for 12 hours at normal temperature to form uniform casting solution. Coating the film casting solution on a polyester non-woven fabric fixed on a glass plate, controlling the thickness of a wet film to be 90 mu m by using a film scraper, then immersing the film in clean water to enable the film and the water phase to generate a phase inversion reaction, forming the film after the reaction and automatically separating the film from the glass plate to obtain a base film, immersing the base film in the clean water for 15h to remove redundant solvent, and then placing the base film in a 60 ℃ drying oven to dry for 4h to obtain the antibacterial asymmetric total heat exchange film.
The total heat exchange membrane can be made into a flat membrane element. Exchange area about 15m2. The detected single-film carbon dioxide transmittance is 2.3 multiplied by 105cm3/m2Day 0.1MPa, making total heat exchanger core with fresh air and exhaust air volume of about 350m3Under the condition of/h, the temperature exchange rate is 75 percent, and the enthalpy exchange rate is 73.2 percent; and (3) testing the antibacterial and mildewproof performance: antibacterial rate against Escherichia coli and Staphylococcus aureus>99.2％。
Example 2
100g of coal-based activated carbon having an iron content of 10 wt% was weighed, and the water content thereof was tested to be 90%. 90g (100g by 90%) of deionized water was weighed, 1g (100g by 1%) of zinc nitrate was added thereto, and the mixture was sufficiently stirred to form a zinc nitrate solution, which was uniformly sprayed onto the coal-based activated carbon and allowed to stand for 6 hours. Then calcining the mixture for 40min at the temperature of 300 ℃ to obtain the antibacterial porous heat-conducting filler.
Measuring 500ml of 60 mass percent acetic acid aqueous solution, adding cellulose acetate and calcium chloride into the aqueous solution to prepare a hydrophilic polymer solution, and controlling the mass percent of the cellulose acetate to be 15% and the mass percent of the calcium chloride to be 5% in the hydrophilic polymer solution; then adding antibacterial porous heat-conducting filler and polyvinylpyrrolidone, controlling the addition of the antibacterial porous heat-conducting filler to be 5 wt% of the hydrophilic polymer solution, and controlling the addition of the polyvinylpyrrolidone to be 1 wt% of the hydrophilic polymer solution; fully stirring and reacting for 6 hours in a water bath kettle at 40 ℃, and standing for 6 hours at normal temperature to form uniform casting solution. Coating the film casting solution on a polyester non-woven fabric fixed on a glass plate, controlling the thickness of a wet film to be 110 mu m by using a film scraper, then immersing the film in clean water to enable the film and the water phase to generate a phase inversion reaction, forming the film after the reaction and automatically separating the film from the glass plate to obtain a base film, immersing the base film in the clean water for 36h to remove redundant solvent, and then placing the base film in a 70 ℃ drying oven to dry for 3h to obtain the antibacterial asymmetric total heat exchange film.
The total heat exchange membrane can be made into a flat membrane element. Exchange area about 10m2. The detected single-film carbon dioxide transmission rate is 6.9 multiplied by 104cm3/m2Day 0.1MPa, making total heat exchanger core with fresh air and exhaust air volume about 400m3Under the condition of/h, the temperature exchange rate is 89%, and the enthalpy exchange rate is 83%; and (3) testing the antibacterial and mildewproof performance: antibacterial rate against Escherichia coli and Staphylococcus aureus>99.9％。
Example 3
100g of activated carbon fiber with iron content of 8 wt% was weighed and tested to have a water capacity of 95%. 95g (100g x 95%) of deionized water was weighed, 0.8g (100g x 0.8%) of copper sulfate was added thereto, and sufficiently stirred to form a copper sulfate solution, which was uniformly sprayed onto the carbon nanotubes, and left to stand for 6 hours. Then calcining the mixture for 35min at the temperature of 500 ℃ to obtain the antibacterial porous heat-conducting filler.
Taking 500ml of 50% formic acid aqueous solution by mass, adding hydroxypropyl cellulose and sodium chloride into the formic acid aqueous solution to prepare a hydrophilic polymer solution, and controlling the mass percentage of the hydroxypropyl cellulose to be 10% and the mass ratio of the sodium chloride to be 15% in the hydrophilic polymer solution; then adding antibacterial porous heat-conducting filler and polyethylene glycol-2000, controlling the addition of the antibacterial porous heat-conducting filler to be 1 wt% of the hydrophilic polymer solution, and controlling the addition of the polyethylene glycol-2000 to be 2 wt% of the hydrophilic polymer solution; fully stirring and reacting for 4 hours in a water bath kettle at the temperature of 80 ℃, and standing for 10 hours at normal temperature to form uniform casting solution. Coating the film casting solution on a polyester non-woven fabric fixed on a glass plate, controlling the thickness of a wet film to be 80 mu m by using a film scraper, then immersing the film casting solution into clean water to enable the film and the water phase to generate a phase inversion reaction, forming the reacted film and automatically separating the film from the glass plate to obtain a base film, immersing the base film into the clean water for 12 hours to remove redundant solvent, and then placing the base film in an oven at 80 ℃ for drying for 2 hours to obtain the antibacterial asymmetric total heat exchange film.
The total heat exchange membrane can be made into a flat membrane element. Exchange area about 15m2. The detected single-film carbon dioxide transmittance is 1.6 multiplied by 104cm3/m2Day 0.1MPa, making total heat exchanger core with fresh air and exhaust air volume about 200m3Under the condition of/h, the temperature exchange rate is 71 percent, and the enthalpy exchange rate is 64 percent; and (3) testing the antibacterial and mildewproof performance: antibacterial rate against Escherichia coli and Staphylococcus aureus>99％。
Comparative example 1
The difference from example 1 is that no antibacterial porous heat-conducting filler is added in the preparation of the casting solution.
The total heat exchange membrane obtained in comparative example 1 was fabricated into a flat membrane element having an exchange area of about 15m2. Making a total heat exchanger core, and keeping fresh air and exhaust air volume at about 350m3Under the condition of/h, the temperature exchange rate is 21 percent, and the enthalpy exchange rate is 13.2 percent; and (3) testing the antibacterial and mildewproof performance: has no antibacterial property to Escherichia coli and Staphylococcus aureus.
Comparative example 2
The difference from example 2 is that no antibacterial porous heat-conducting filler is added in the preparation of the casting solution.
The total heat exchange membrane obtained in comparative example 2 was fabricated into a flat membrane element having an exchange area of about 10m2. Making a total heat exchanger core, and the fresh air and exhaust air volume is about 400m3Under the condition of/h, the temperature exchange rate is 61.3 percent, and the enthalpy exchange rate is 34.2 percent; and (3) testing the antibacterial and mildewproof performance: has no antibacterial property to Escherichia coli and Staphylococcus aureus.
Comparative example 3
The difference from example 3 is that no antibacterial porous heat-conducting filler was added in the preparation of the casting solution.
The total heat exchange membrane obtained in comparative example 3 was fabricated into a flat membrane element having an exchange area of about 15m2. Making a total heat exchanger core, and keeping fresh air and exhaust air volume about 200m3Under the condition of/h, the temperature exchange rate is 51 percent, and the enthalpy exchange rate is 23.1 percent; and (3) testing the antibacterial and mildewproof performance: has no antibacterial property to Escherichia coli and Staphylococcus aureus.
Compared with the scheme that graphene, aluminum nitride or silicon carbide is used as the heat-conducting filler in the prior art, the antibacterial asymmetric total heat exchange membrane provided by the application has the advantages that the heat-conducting filler has a developed pore structure, a good heat-conducting passage can be formed, micropores in the membrane cannot be blocked even under the condition that the addition amount is relatively large, the transmittance is high, and the mechanical property is excellent. The heat conductivity coefficient of the material produced by the traditional composite membrane technology is generally 0.1-1W/m.K, and the porous heat-conducting filler with a certain iron content provided by the invention can effectively solve the problems and simultaneously improve the heat conductivity coefficient to 15-40W/m.K.
The application provides an antibiotic asymmetric total heat exchange membrane of type, total heat exchange core and total heat exchanger, heat conductivity, moisture permeability are high, can realize the whole recovery of sensible heat and latent heat, and the heat exchange rate is high, and simple process is with low costs, and antibiotic, mould proof efficiency are good, stop secondary pollution, long service life.
While particular embodiments of the present invention have been illustrated and described, it would be obvious that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
Claims (9)
1. An antibacterial asymmetric total heat exchange membrane is characterized in that the preparation method comprises the following steps:
A. loading an antibacterial agent on the porous heat-conducting filler to obtain the antibacterial porous heat-conducting filler;
B. dissolving a high molecular polymer and hygroscopic metal salt in a solvent to prepare a hydrophilic polymer solution, then mixing the antibacterial porous heat-conducting filler and the pore-forming agent with the hydrophilic polymer solution, heating, stirring and standing to obtain a membrane casting solution;
C. coating the film casting solution on non-woven fabric fixed on a glass plate, then immersing the non-woven fabric in water, and carrying out phase inversion reaction to obtain a base film; taking out the base membrane, soaking the base membrane in water, and drying to obtain the antibacterial asymmetric total heat exchange membrane; the porous heat-conducting filler is one or more of carbon nano tubes, activated carbon and activated carbon fibers, the iron content of the carbon nano tubes is 3-10 wt%, and the iron content of the activated carbon and the activated carbon fibers is 8-20 wt%; the loading process of the antibacterial agent is as follows: and adding the antibacterial agent into water to be fully dissolved, spraying the antibacterial agent into the porous heat-conducting filler, standing, and calcining at the temperature of 300-500 ℃ for 30-40min to obtain the antibacterial porous heat-conducting filler.
2. The asymmetric antibacterial enthalpy-exchange membrane according to claim 1, characterized in that the antibacterial agent is a mixture of one or more of compounds containing silver ions, copper ions or zinc ions; the dosage of the antibacterial agent is 0.5-1% of the weight of the porous heat-conducting filler.
3. The asymmetric antibacterial perheat exchange membrane as claimed in claim 1, wherein the high molecular polymer is one of cellulose acetate and hydroxypropyl cellulose, the hygroscopic metal salt is one of lithium chloride, calcium chloride, sodium chloride, potassium chloride and magnesium chloride, the solvent is an aqueous solution of acetic acid or formic acid with a mass fraction of 10-60%, and the pore-forming agent is polyvinyl alcohol or polyvinylpyrrolidone; in the hydrophilic polymer solution, the mass percentage of the high molecular polymer is 10-25%, and the mass ratio percentage of the hygroscopic metal salt is 1.5-15%.
4. The asymmetric antibacterial total heat exchange membrane as claimed in claim 3, wherein the addition amount of the antibacterial porous heat-conducting filler is 1-10 wt% of the hydrophilic polymer solution, and the addition amount of the pore-forming agent is 0.5-2 wt% of the hydrophilic polymer solution.
5. The asymmetric antibacterial total heat exchange membrane as claimed in claim 4, wherein the heating temperature is 40-80 ℃, the heating time is 4-6h, the standing is performed at normal temperature, and the standing time is 6-12 h.
6. The asymmetric antibacterial total heat exchange membrane as claimed in claim 1, wherein the non-woven fabric is one of terylene, polypropylene and acrylic; the thickness of the casting solution coated on the non-woven fabric is 80-110 μm.
7. The asymmetric antibacterial perheat exchange membrane according to any one of claims 1 to 6, wherein the soaking time is 12 to 36 hours; the drying temperature is 60-80 ℃ and the drying time is 2-4 h.
8. An enthalpy exchanger core, characterized in that it is made using an antibacterial asymmetric enthalpy exchange membrane according to any one of claims 1 to 7.
9. An enthalpy exchanger comprising the enthalpy exchanger core of claim 8.
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| WO2021216010A1 (en) * | 2020-04-22 | 2021-10-28 | Enerama Çevre Teknoloji̇leri̇ Sanayi̇ Ve Ti̇caret Anoni̇m Şi̇rketi̇ | An air cleaning device |
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