Composite dehumidification rotating wheel and preparation method thereof

Abstract

The invention belongs to the field of dehumidification equipment, and particularly relates to a composite dehumidification rotating wheel and a preparation method thereof. The composite dehumidifying rotating wheel comprises a rotating wheel main body which is a heat conduction base material; the adsorbent is loaded on the first side surface of the runner main body; the heat conduction coating is loaded on the second side surface of the runner main body; wherein the heat conduction coating is used for promoting the heat absorption and heat release capacity of the heat conduction base material, heat at the air supply position is recycled and released at the regeneration position, and recycling of the heat is achieved. The composite dehumidification rotating wheel capable of achieving heat recovery to a certain extent is applied to a dehumidifier, heat utilization between air supply surface cooling and regenerative heating is achieved, the power consumption of a compressor and an electric heater is reduced, and therefore the energy consumption of the dehumidifier is reduced.

Description

Technical Field

[0001] This invention belongs to the field of dehumidification equipment, and particularly relates to a composite dehumidification impeller and its preparation method. Background Technology

[0002] With the continuous development of society, people's requirements for air quality are gradually increasing, especially for humidity control. In the field of dehumidification, rotary dehumidification systems have seen significant development due to their advantages of large dehumidification capacity, high efficiency, and ability to continuously provide low dew point dry air. The core component of a rotary dehumidifier is a dehumidification rotor loaded with adsorbent. In the adsorption zone of the rotor, moisture in the air is captured by the adsorbent, while in the regeneration zone, high-heat air causes the adsorbent to desorb and regenerate.

[0003] The basic process of rotary dehumidifier is as follows: Figure 1 After outdoor air passes through the primary filter and surface cooling to remove most of the moisture, it passes through the rotary adsorption and is then delivered to the indoor (processing space). Since the rotary adsorption is an exothermic process, there will be a significant temperature rise at the rotary outlet, which is generally higher than the indoor temperature requirement. Therefore, surface cooling is required when the air is delivered indoors. The desorption process is the opposite and is an endothermic process. Therefore, the desorbed air needs to be externally heated. The hot air regenerates the rotary wheel and carries the moisture out outdoors.

[0004] During the operation of the rotary turbine, there is very little heat recycling in the air supply cooling and regenerative heating processes. Generally, refrigeration compressors and electric heaters rely on the conversion of electrical energy into heat energy, resulting in enormous energy consumption. With increasing societal concern about energy consumption, and given that electricity is currently the primary energy source, it inevitably contributes to global environmental pollution. Improving the heat utilization rate during rotary turbine operation can not only save costs to some extent but also effectively reduce electricity consumption.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] The purpose of this invention is to alleviate the problem of low heat utilization rate in the operation of traditional dehumidifying rotors, realize the heat utilization between air supply surface cooling and regeneration heating, reduce the power consumption of compressor and electric heater, thereby reducing the energy consumption of dehumidifier, and provide a composite dehumidifying rotor that can realize heat recovery and its preparation method to solve the above problems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides a composite dehumidifying impeller, the composite dehumidifying impeller comprising:

[0009] The main body of the rotor is made of a heat-conducting substrate;

[0010] Adsorbent, loaded on the first side surface of the rotor body; and

[0011] A thermally conductive coating is applied to the second side surface of the rotor body; wherein,

[0012] The thermally conductive coating is used to enhance the heat absorption and release capabilities of the thermally conductive substrate, recovering heat at the air supply point and releasing it at the regeneration point, thereby achieving heat recovery and utilization.

[0013] Preferably, the adsorbent comprises a silica gel adsorbent.

[0014] Preferably, the thermally conductive coating comprises one of graphene oxide, carbon nanotubes, porous carbon, or black titanium dioxide.

[0015] Preferably, the thermally conductive substrate includes an aluminum foil substrate or an aluminum alloy substrate.

[0016] This invention provides a method for preparing the composite dehumidifying impeller, comprising the following steps:

[0017] 1) The heat-conducting substrate is made into a rotor blank, soaked in an alkaline solution and dried to obtain the rotor body;

[0018] 2) Immerse the first side surface of the rotor body obtained in step (1) in the adsorbent solution with the surface facing down, and repeatedly lift and immerse it, and then dry it.

[0019] 3) Immerse the rotor obtained in step (2) in an acid solution, stir, wash, dry and calcine to obtain a rotor body with adsorbent;

[0020] 4) Prepare a composite heat-conducting slurry. Immerse the second side surface of the rotor body obtained in step (3) into the composite heat-conducting slurry with the surface facing down. Immerse and dry to obtain a composite dehumidifying rotor.

[0021] Preferably, in step 1), the diameter of the wheel blank is 35-65cm and the thickness is 8-12cm, the concentration of the alkaline solution is 8%-12%, and it is soaked for 2-5 hours. The alkaline solution is sodium hydroxide solution or potassium hydroxide solution, etc.

[0022] Preferably, in step 2), the impregnation temperature is 20-28℃ and the impregnation thickness is 5-8cm.

[0023] The concentration of the adsorbent solution is 25%-35%;

[0024] The drying temperature is below 80℃.

[0025] Preferably, in step 3), the pH value of the acid solution is 1-3, and the solution is immersed in a water bath at 30-70°C for 2-4 hours. The acid solution is concentrated sulfuric acid or concentrated hydrochloric acid, etc.

[0026] After the reaction is complete, remove excess reaction liquid from the rotor, wash until the effluent is neutral, dry, and then calcine at 120-150℃ for 2-6 hours.

[0027] Preferably, in step 4), the impregnation thickness is 3-4 cm, the impregnation time is 15-25 min, and the drying temperature is 120-140℃.

[0028] The key technologies of this invention are: (1) The composite dehumidifying wheel substrate is selected from thermally conductive substrates, which have excellent thermal conductivity and high strength, and the wheel has a longer lifespan; (2) The first side surface of the wheel retains normal dehumidification capacity, and the second side surface is combined with a thermally conductive coating to efficiently recover and utilize heat; (3) The wheel preparation process is simple, safe and free of harmful products, and more environmentally friendly.

[0029] The beneficial effects of this invention are:

[0030] This invention relates to a composite dehumidifying impeller that can achieve heat recovery to a certain extent. When applied in a dehumidifier, it enables the utilization of heat between the supply air surface cooling and regeneration heating, thereby reducing the power consumption of the compressor and electric heater and thus reducing the energy consumption of the dehumidifier. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a process diagram of a dehumidification rotor in the existing technology;

[0033] Figure 2 This is a schematic diagram of the A and B sides of the composite rotor and the airflow state of the present invention;

[0034] Figure 3 This is a schematic diagram showing the black graphene oxide material loaded on the B-side surface of the rotor of the present invention. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] First, the present invention will be explained in its entirety, as follows:

[0037] This invention provides a composite dehumidifying impeller, such as... Figure 2-3 As shown, the composite dehumidification rotor includes:

[0038] The main body of the rotating wheel is a heat-conducting substrate, which includes an aluminum foil substrate or an aluminum alloy substrate;

[0039] An adsorbent is loaded on the first side surface of the rotor body; the adsorbent includes a silica gel adsorbent.

[0040] and

[0041] A thermally conductive coating is applied to the second side surface of the rotor body; the thermally conductive coating includes one of graphene oxide, carbon nanotubes, porous carbon, or black titanium dioxide.

[0042] in,

[0043] The thermally conductive coating is used to enhance the heat absorption and release capabilities of the thermally conductive substrate, recovering heat at the air supply point and releasing it at the regeneration point, thereby achieving heat recovery and utilization.

[0044] This invention provides a method for preparing the composite dehumidifying impeller, comprising the following steps:

[0045] (1) Press the aluminum foil substrate into a roller blank with a diameter of 45-55cm and a thickness of 8-12cm by a roller press. Soak the entire blank in an 8%-12% sodium hydroxide solution or potassium hydroxide solution for 2-5 hours, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0046] (2) Immerse the rotor A obtained in step (1) with its face down in water glass with a concentration of 25%-35% at room temperature, with an immersion thickness of 5-8cm. After repeated lifting and immersion, remove excess water glass and dry at below 80℃.

[0047] (3) Dilute concentrated sulfuric acid or concentrated hydrochloric acid, adjust the pH to 1-3, and immerse the rotor obtained in step (2) in the reaction solution under a water bath at 30-70℃, ensuring that the reaction solution is stirred continuously for 2-4 hours.

[0048] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 120-150℃ for 3-5 hours to obtain the dehumidified rotor substrate.

[0049] (5) Dissolve 5-15g of GO (i.e., graphene oxide) in 10L of water, sonicate at room temperature for 2h, then add 100g of polyethyleneimine and mix for 2h to obtain a composite thermally conductive slurry.

[0050] (6) Immerse the dehumidifying rotor substrate B obtained in step (4) with its B side facing down in the slurry obtained in step (5) with an immersion thickness of 3-4 cm. After 15-25 minutes, remove it, blow off the excess slurry, and dry it at 120-140℃ after vacuum filtration to obtain a composite dehumidifying rotor that can realize heat recovery.

[0051] In step (2), the water glass concentration is optimal at 28%-32% to remove excess water glass and prevent clogging of the hole;

[0052] In step (3), the optimal pH of sulfuric acid or hydrochloric acid is 1.8-2.2, the optimal water bath temperature is 45-50℃, and the optimal reaction time is 2.5-3h.

[0053] In step (4), the drying temperature is best at 125-130℃. Too high a temperature can easily damage the adsorbent, while too low a temperature is not conducive to activation.

[0054] In step (5), the optimal amount of GO, carbon nanotubes, porous carbon or black titanium dioxide is 8-10g. A large amount will result in poor thermal conductivity and affect the heat exchange efficiency. A large amount will easily cause the rotor to become clogged.

[0055] In step (6), the optimal drying temperature is 125-130℃. If the temperature is too low, the drying time will be too long, and if the temperature is too high, the drying speed will be too fast, which may cause the product to fall off.

[0056] The composite dehumidifying rotor of this invention uses aluminum foil as its substrate, which has excellent thermal conductivity and high strength, resulting in a longer rotor life. Side A of the rotor retains normal dehumidification capacity, while side B uses aluminum foil combined with graphene material for efficient heat recovery and utilization. The rotor manufacturing process is simple, safe, and produces no harmful products, making it more environmentally friendly.

[0057] Example 1

[0058] (1) Press the aluminum foil substrate into a roller blank with a diameter of 50cm and a thickness of 10cm by a roller press. Soak the entire blank in a sodium hydroxide solution of about 10% for 3 hours, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0059] (2) Immerse the rotor A obtained in step (1) with its face down in 30% water glass at room temperature, with an immersion thickness of 7cm. After repeatedly lifting and immersing, remove excess water glass and dry at below 80℃.

[0060] (3) Dilute concentrated sulfuric acid, adjust pH to 2, and immerse the rotor obtained in step (2) in the reaction solution under a 50°C water bath, ensuring that the reaction solution is stirred continuously for 3 hours;

[0061] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 130°C for 4 hours to obtain the dehumidified rotor substrate.

[0062] (5) Dissolve 10g of GO (i.e., graphene oxide) in 10L of water, sonicate at room temperature for 2h, then add 100g of polyethyleneimine and mix for 2h to obtain a composite thermally conductive slurry.

[0063] (6) Immerse the dehumidifying rotor substrate B obtained in step (4) with its B side facing down in the slurry obtained in step (5) with an immersion thickness of 3 cm. After 20 min, remove it, blow off the excess slurry, and dry it at 130°C after vacuum filtration to obtain a composite dehumidifying rotor that can realize heat recovery, denoted as composite rotor 1.

[0064] Example 2

[0065] (1) Press the aluminum foil substrate into a roller blank with a diameter of 45cm and a thickness of 8cm by a roller press. Soak the entire blank in an 11% potassium hydroxide solution for 2.5h, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0066] (2) Immerse the rotor A obtained in step (1) with its face down in 30% water glass at room temperature, with an immersion thickness of 5cm. After repeated lifting and immersion, remove excess water glass and dry at below 80℃.

[0067] (3) Dilute concentrated sulfuric acid, adjust pH to 3, and immerse the rotor obtained in step (2) in the reaction solution under a 40°C water bath, ensuring that the reaction solution is stirred continuously for 3 hours;

[0068] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 140°C for 4 hours to obtain the dehumidified rotor substrate.

[0069] (5) Dissolve 5g of GO (i.e., graphene oxide) in 10L of water, sonicate at room temperature for 2h, then add 100g of polyethyleneimine and mix for 2h to obtain a composite thermally conductive slurry.

[0070] (6) Immerse the dehumidifying rotor substrate B obtained in step (4) with its B side facing down in the slurry obtained in step (5) with an immersion thickness of 3 cm. After 20 min, take it out, blow off the excess slurry, and dry it at 120°C after vacuum filtration to obtain a composite dehumidifying rotor that can realize heat recovery, denoted as composite rotor 2.

[0071] Example 3

[0072] (1) Press the aluminum foil substrate into a roller blank with a diameter of 55cm and a thickness of 10cm by a roller press. Soak the entire blank in an 8% sodium hydroxide solution for 3 hours, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0073] (2) Immerse the rotor A obtained in step (1) with its face down in water glass with a concentration of 35% at room temperature, with an immersion thickness of 7cm. After repeatedly lifting and immersing, remove excess water glass and dry at a temperature below 80℃.

[0074] (3) Dilute concentrated hydrochloric acid, adjust pH to 1, and immerse the rotor obtained in step (2) in the reaction solution under a 60°C water bath, ensuring that the reaction solution is stirred continuously for 3 hours.

[0075] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 130°C for 4 hours to obtain the dehumidified rotor substrate.

[0076] (5) Dissolve 15g of carbon nanotubes in 10L of water, sonicate at room temperature for 2h, then add 100g of polyethyleneimine and mix for 2h to obtain a composite thermally conductive slurry.

[0077] (6) Immerse the dehumidifying rotor substrate B obtained in step (4) with its B side facing down in the slurry obtained in step (5) with an immersion thickness of 3 cm. After 20 min, remove it, blow off the excess slurry, and dry it at 130°C after vacuum filtration to obtain a composite dehumidifying rotor that can realize heat recovery, denoted as composite rotor 3.

[0078] Comparative Example 1

[0079] (1) Press the aluminum foil substrate into a roller blank with a diameter of 50cm and a thickness of 7cm using a roller press. Soak the entire blank in a 10% sodium hydroxide solution for 3 hours, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0080] (2) Immerse the rotor A obtained in step (1) with its face down in 30% water glass at room temperature, with an immersion thickness of 7cm. After repeatedly lifting and immersing, remove excess water glass and dry at below 80℃.

[0081] (3) Dilute concentrated sulfuric acid, adjust pH to 2, and immerse the rotor obtained in step (2) in the reaction solution under a 50°C water bath, ensuring that the reaction solution is stirred continuously for 3 hours;

[0082] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 130°C for 4 hours to obtain the dehumidifying rotor substrate. This rotor only contains the dehumidifying part and is called the control rotor 1.

[0083] Comparative Example 2

[0084] (1) Press the aluminum foil substrate into a roller blank with a diameter of 50cm and a thickness of 10cm by a roller press. Soak the entire blank in a sodium hydroxide solution of about 10% for 3 hours, then wash and dry it for later use (the two sides of the roller are marked as A and B respectively).

[0085] (2) Immerse the rotor A obtained in step (1) with its face down in 30% water glass at room temperature, with an immersion thickness of 7cm. After repeatedly lifting and immersing, remove excess water glass and dry at below 80℃.

[0086] (3) Dilute concentrated sulfuric acid, adjust pH to 2, and immerse the rotor obtained in step (2) in the reaction solution under a 50°C water bath, ensuring that the reaction solution is stirred continuously for 3 hours;

[0087] (4) After the reaction is complete, remove the excess reaction liquid from the rotor, wash it with deionized water until the effluent is neutral, dry it and calcine it at 130°C for 4 hours to obtain the dehumidified rotor substrate. The rotor is not coated with graphene oxide on side B and is called control rotor 2.

[0088] test

[0089] 1) Static water absorption capacity test

[0090] Five sample rotors were dried at 120℃ for 2 hours and then placed in a fixed temperature environment. Weight changes were recorded at regular intervals, and the weight gain rate, which is the water absorption rate, was calculated, as shown in the table below. In sample rotor 1 of the example, the adsorbent ratio and reaction conditions were moderate, resulting in relatively high adsorption performance. In sample rotor 2 of the example, the water glass concentration was low, the pH of the reaction solution was low, and the adsorbent ratio was low, resulting in poor adsorption performance. In sample rotor 3 of the example, the water glass concentration was high, the adsorbent ratio was large, and the weight gain rate was relatively high.

[0091] The comparative sample was prepared with Example 1 as the comparison. Although the adsorbent preparation ratio of the comparative composite rotor 1 was the same as that of Example 1, the adsorbent ratio was higher due to the lower rotor thickness and total rotor weight. The difference between the comparative rotor 2 and Example 1 is that the B side was not coated with graphene oxide, which had little impact on the adsorption performance, as shown in Table 1.

[0092] Table 1

[0093]

[0094] 2) Test of the heat absorption capacity of the rotor

[0095] After the five rotors were left to stand indoors for 3 hours, the surface temperature of their B-side was measured and recorded. The rotors were then transferred to a 40℃ drying oven and left to stand for another 3 hours. The surface temperature of the B-side of each rotor was measured using a temperature gun. Composite rotor 1 showed an approximately 8℃ temperature rise on its B-side after standing. Composite rotor 2 had a low graphene oxide content, resulting in low heat exchange efficiency and a relatively low temperature rise. Composite rotor 3 had a high graphene oxide content, leading to stronger heat absorption capacity. Comparative rotor 1 can be considered a conventional rotor with the lowest heat absorption performance. Comparative rotor 2 had no thermally conductive layer coated on its B-side, resulting in lower heat absorption capacity, as shown in Table 2.

[0096] Table 2

[0097]

[0098]

[0099] 3) Dynamic performance test of dehumidifying impeller

[0100] Five dehumidifier rotor samples were placed inside the dehumidifier rotor for dynamic testing. The rotor inlet conditions were uniformly set as follows: 12℃, 95% RH, 8.3 g / kg, rotor speed 8 r / h, and adsorption air volume 1500 m³ / h. 3 / h, desorption air volume 500m³ 3 / h, by adjusting the regeneration temperature to the moisture content at the outlet of each impeller to 4±0.2g / kg, the supply air temperature and regeneration temperature of each impeller are recorded.

[0101] With a similar overall dehumidification capacity, composite rotor 1 requires a regeneration temperature of only 116.9℃ and an air supply temperature of 15.1℃. Composite rotor 2 has a low graphene oxide content, resulting in lower heat exchange efficiency and a higher air supply temperature, thus recovering less heat and requiring a higher regeneration temperature. Composite rotor 3 has a high graphene oxide content, which is more conducive to heat conduction, resulting in higher heat recovery and correspondingly lower air supply and regeneration temperatures. In contrast, rotor 1 can be considered a conventional rotor with almost no heat recovery capacity, and both air supply and regeneration temperatures are relatively high. In contrast, rotor 2 has no graphene oxide on its B side, resulting in poor thermal conductivity and lower heat recovery capacity than composite rotor 1 (Table 3).

[0102] Table 3

[0103]

[0104] The composite dehumidifying rotor of the present invention uses aluminum foil as the substrate, which is easy to form and has high strength. At the same time, aluminum foil has excellent heat absorption properties. One side of the rotor A serves as the adsorption inlet side and is coated with silica gel adsorbent to provide high dehumidification capacity. The aluminum foil surface of the rotor B side is coated with graphene oxide to enhance thermal conductivity and promote the heat absorption and release capacity of the aluminum foil substrate. It recovers the heat at the air supply point and releases it at the regeneration point, realizing the recovery and utilization of heat.

[0105] Please note that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The above embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A composite dehumidifying impeller, characterized in that, The composite dehumidification rotor includes: The main body of the rotor is made of a heat-conducting substrate; Adsorbent, loaded on the first side surface of the rotor body; and A thermally conductive coating is applied to the second side surface of the rotor body; wherein, The thermally conductive coating is used to enhance the heat absorption and release capabilities of the thermally conductive substrate, recovering heat at the air supply point and releasing it at the regeneration point, thereby achieving heat recovery and utilization.

2. The composite dehumidifying impeller according to claim 1, characterized in that, The adsorbent includes silica gel adsorbent.

3. The composite dehumidifying impeller according to claim 1, characterized in that, The thermally conductive coating includes one of graphene oxide, carbon nanotubes, porous carbon, or black titanium dioxide.

4. The composite dehumidifying impeller according to claim 1, characterized in that, The thermally conductive substrate includes an aluminum foil substrate or an aluminum alloy substrate.

5. A method for preparing the composite dehumidifying impeller according to any one of claims 1-4, comprising the following steps: 1) The heat-conducting substrate is made into a rotor blank, soaked in an alkaline solution and dried to obtain the rotor body; 2) Immerse the first side surface of the rotor body obtained in step (1) in the adsorbent solution with the surface facing down, and repeatedly lift and immerse it, and then dry it. 3) Immerse the rotor obtained in step (2) in an acid solution, stir, wash, dry and calcine to obtain a rotor body with adsorbent; 4) Prepare a composite heat-conducting slurry. Immerse the second side surface of the rotor body obtained in step (3) into the composite heat-conducting slurry with the surface facing down. Immerse and dry to obtain a composite dehumidifying rotor.

6. The preparation method according to claim 5, characterized in that, In step 1), the diameter of the wheel blank is 35-65cm, the thickness is 8-12cm, the concentration of the alkaline solution is 8%-12%, and it is soaked for 2-5 hours.

7. The preparation method according to claim 5, characterized in that, In step 2), the impregnation temperature is 20-28℃, and the impregnation thickness is 5-8cm; The concentration of the adsorbent solution is 25%-35%; The drying temperature is below 80℃.

8. The preparation method according to claim 5, characterized in that, In step 3), the pH value of the acid solution is 1-3, and the solution is immersed in a water bath at 30-70℃ for 2-4 hours. After the reaction is complete, remove excess reaction liquid from the rotor, wash until the effluent is neutral, dry, and then calcine at 120-150℃ for 2-6 hours.

9. The preparation method according to claim 5, characterized in that, In step 4), the impregnation thickness is 3-4 cm, the impregnation time is 15-25 min, and the drying temperature is 120-140℃.

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