A refrigerant R134a dehydration device

Abstract

The utility model discloses a refrigerant R134a dehydration device. By arranging two or more dehydration adsorption towers in series in an adsorption unit, the R134a raw material can be continuously subjected to multi-stage adsorption dehydration treatment. The R134a raw material can be efficiently removed of water in the R134a raw material after multi-stage adsorption purification, and finally an R134a product with a water content of ≤0.1ppm (w%) is collected. The above-mentioned refrigerant R134a dehydration device is suitable for deep dehydration of R134a, adopts adsorbent adsorption dehydration, and has the advantages of energy saving and consumption reduction.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical industry, relates to a purification technology of an environmentally friendly refrigerant, and in particular to a refrigerant R134a dehydration device. Background Art

[0002] 1,1,1,2-tetrafluoroethane (R134a) is a third-generation refrigerant, belonging to the HFC class, does not contain chlorine atoms, and is an environmentally friendly refrigerant. At present, the water content in industrial-grade R134a products is ≤10ppm (w%), and is mainly used in large refrigerators such as car air conditioners, central air conditioners, and refrigerators. However, precision temperature controllers have more stringent requirements on the water content in R134a, requiring the water content to be ≤0.1ppm (w%).

[0003] At present, the main methods for removing water from R134a are distillation and adsorption, but the R134a products obtained by the current methods cannot reach the target of water content ≤ 0.1ppm (w%). For example, the device for separating and purifying R134a using distillation technology disclosed in the Chinese utility model patent with publication number CN216755432U has a water content of 7ppm in the R134a product after water removal, which cannot meet the requirements of a higher precision temperature controller; the method for drying R134a products using 5A molecular sieve disclosed in the Chinese utility model patent with publication number CN115626864A, after experimental comparison, found that the water removal depth of 5A molecular sieve in R134a products still does not reach ≤ 0.1ppm (w%).

[0004] In summary, it is urgent to propose a new dehydration and purification scheme for refrigerant R134a to meet the requirements of higher precision temperature controllers for the water content in R134a. Utility Model Content

[0005] The purpose of the utility model is to provide a refrigerant R134a dehydration device, which can reduce the water content in R134a to ≤0.1ppm by adsorbing and removing water in R134a, so as to solve the problem that the removal depth of the above-mentioned existing R134a dehydration technology cannot reach ≤0.1ppm, thereby failing to meet the requirements of a higher-precision temperature controller for the water content in R134a.

[0006] To achieve the above purpose, the utility model provides the following solutions:

[0007] The utility model provides a refrigerant R134a dehydration device, comprising:

[0008] An adsorption unit, comprising at least two dehydration adsorption towers arranged in series along the flow direction of the raw material, so as to perform at least two-stage adsorption and dehydration on the R134a raw material in sequence;

[0009] a filtration system having an inlet communicating with an outlet of the adsorption unit;

[0010] A product collection device having an inlet communicating with an outlet of the filtration system.

[0011] Preferably, it also includes a moisture measuring device, and the outlet of any one of the dehydration adsorption towers is connected to the moisture measuring device, and the moisture measuring device is used to detect the water content of the outlet product of any one of the dehydration adsorption towers.

[0012] Preferably, a purge unit is further included, and the inlet of any one of the dehydration adsorption towers is connected to the outlet of the purge unit.

[0013] Preferably, a vacuum unit is further included, and the inlet of any one of the dehydration adsorption towers is connected to the vacuum unit.

[0014] Preferably, the vacuum unit comprises a vacuum buffer tank, a vacuum pump and an exhaust gas treatment system which are connected in sequence, the inlet of the vacuum buffer tank is connected to the inlet of any one of the dehydration adsorption towers, and the vacuum buffer tank is also directly connected to the exhaust gas treatment system.

[0015] Preferably, the adsorption unit comprises a first dehydration adsorption tower and a second dehydration adsorption tower which are sequentially arranged in series along the flow direction of the raw material, wherein:

[0016] The adsorbent disposed in the first dehydration adsorption tower includes a type A molecular sieve adsorbent and / or a modified type A molecular sieve adsorbent;

[0017] The adsorbent arranged in the second dehydration adsorption tower includes a metal ion-modified nano ZSM-5 molecular sieve adsorbent and / or a metal ion-modified nano TS-1 molecular sieve adsorbent.

[0018] Preferably, it further comprises a raw material storage device connected to the inlet of the adsorption unit, and the raw material storage device is used to store and provide the R134a raw material to be dehydrated to the adsorption unit.

[0019] Preferably, the method further comprises a flow meter connected between the inlet of the adsorption unit and the raw material storage device.

[0020] The utility model also provides a refrigerant R134a dehydration method, which is implemented by using the above refrigerant R134a dehydration device, comprising:

[0021] The R134a raw material is introduced into the adsorption unit, and the first dehydration adsorption tower and the second dehydration adsorption tower respectively perform primary adsorption dehydration and secondary adsorption dehydration on the R134a raw material;

[0022] The water content of the product at the outlet of the second dehydration adsorption tower is detected by the moisture measuring device until the water content of the product at the outlet of the second dehydration adsorption tower is ≤0.1ppm, and the product at the outlet of the second dehydration adsorption tower is discharged into the product collecting device for collection.

[0023] Preferably, the weight space velocity of the R134a raw material passing into the adsorption unit is 0.05 to 1.2 h -1 ; The adsorption temperature of the first dehydration adsorption tower is room temperature, and the adsorption pressure is 0.1~0.5MPa; The adsorption temperature of the second dehydration adsorption tower is room temperature, and the adsorption pressure is 0.1~1.0MPa.

[0024] Compared with the prior art, the utility model has achieved the following technical effects:

[0025] The refrigerant R134a dehydration device proposed by the utility model can continuously perform multi-stage adsorption dehydration treatment on the R134a raw material by arranging two or more dehydration adsorption towers in series in the adsorption unit. The R134a raw material can be efficiently removed from the water in the R134a raw material after multi-stage adsorption purification, and finally the R134a product with a water content of ≤0.1ppm (w%) is collected. The above refrigerant R134a dehydration device is suitable for deep dehydration of R134a, adopts adsorbent adsorption dehydration, and has the advantages of energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 This is a schematic structural diagram of a refrigerant R134a dehydration device disclosed in an embodiment of the utility model;

[0028] Figure 2 This is a schematic diagram of the installation of a purge unit and a vacuum unit in a refrigerant R134a dehydration device disclosed in an embodiment of the utility model.

[0029] In the figure, the reference numerals are:

[0030] 100. Refrigerant R134a dehydration device;

[0031] 1. Raw material storage device;

[0032] 2. Flow meter;

[0033] 3. adsorption unit; 31. first dehydration adsorption tower; 32. second dehydration adsorption tower;

[0034] 4. Filtration system;

[0035] 5. Moisture measuring device;

[0036] 6. Product collection device;

[0037] 7. Purge unit;

[0038] 8. Vacuum unit; 81. Vacuum buffer tank; 82. Vacuum pump; 83. Exhaust gas treatment system;

[0039] K1~K11, valve. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0041] The utility model aims to provide a refrigerant R134a dehydration device, which can reduce the water content in R134a to ≤0.1ppm by adsorbing and removing water in R134a, so as to solve the problem that the removal depth of the existing R134a dehydration technology cannot reach ≤0.1ppm, thereby failing to meet the requirements of a higher-precision temperature controller for the water content in R134a.

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] Embodiment 1

[0044] like Figure 1 As shown, this embodiment provides a refrigerant R134a dehydration device 100, including an adsorption unit 3, a filter system 4 whose inlet is connected to the outlet of the adsorption unit 3, a product collection device 6 whose inlet is connected to the outlet of the filter system 4, and a moisture measuring device 5. The adsorption unit 3 includes at least two dehydration adsorption towers arranged in series along the flow direction of the raw material, so as to perform at least two-stage adsorption dehydration on the R134a raw material in sequence; the inlet of the moisture measuring device 5 is connected to the outlet of any dehydration adsorption tower, and the moisture measuring device 5 is used to detect the water content of the outlet product of any dehydration adsorption tower. The moisture measuring device 5 preferably adopts an online moisture analyzer.

[0045] In this embodiment, the adsorption unit 3 may specifically include a first dehydration adsorption tower 31 and a second dehydration adsorption tower 32 which are sequentially arranged in series along the flow direction of the raw material, wherein the adsorbent arranged in the first dehydration adsorption tower 31 includes a type A molecular sieve adsorbent and / or a modified type A molecular sieve adsorbent, and the adsorbent arranged in the second dehydration adsorption tower 32 includes a metal ion-modified nano ZSM-5 molecular sieve adsorbent and / or a metal ion-modified nano TS-1 molecular sieve adsorbent. Based on this, the inlet of the moisture measuring device 5 is connected to the outlets of the first dehydration adsorption tower 31 and the second dehydration adsorption tower 32.

[0046] Furthermore, the above-mentioned type A molecular sieve adsorbent can specifically adopt 3A, 4A or 5A molecular sieves, and more preferably spherical 3A molecular sieves. The preparation method of the modified type A molecular sieve adsorbent comprises the following steps: mixing the type A molecular sieve and the acid solution for acid exchange to obtain an acid-modified type A molecular sieve. The above-mentioned acid solution preferably includes an aqueous nitric acid solution or an aqueous acetic acid solution, and more preferably an aqueous nitric acid solution; the molar concentration of the acid solution is preferably 0.05-10 mol / L, and more preferably 0.1-5 mol / L; the solid-liquid ratio of the type A molecular sieve and the acid solution is preferably 1:1-50, and more preferably 1:5-30; the temperature of the acid exchange is preferably 50-120°C, and more preferably 60-100°C; the time of the acid exchange is preferably 8-48h, and more preferably 12-24h.

[0047] Furthermore, in this embodiment, the adsorbent of the first dehydration adsorption tower 31 is preferably one of a type A molecular sieve adsorbent and a modified type A molecular sieve adsorbent, which can reduce the water content in the R134a raw material to about 15 ppm.

[0048] Furthermore, the carrier of the metal ion-modified nano ZSM-5 molecular sieve adsorbent is preferably a molded ZSM-5 molecular sieve with a grain size of 20 to 100 nm and a silicon-aluminum ratio of 20 to 100; the carrier of the metal ion-modified nano TS-1 molecular sieve adsorbent is preferably a molded TS-1 molecular sieve with a grain size of 20 to 100 nm and a silicon-titanium ratio of 40 to 100. This scheme has no special restrictions on the preparation method of the nano ZSM-5 molecular sieve carrier and the nano TS-1 molecular sieve carrier, and the preparation method known in the art can be used, such as "Effect of treatment with different bases on the catalytic properties of TS-1 / SiO2 extrudates in propylene epoxidation" (Microporous and Mesoporous Materials, 2015, 212: 48-55) or the hydrothermal synthesis method disclosed in the utility model patent with publication number CN102502696A for preparing nano TS-1 molecular sieve or ZSM-5 molecular sieve. The shape of nano TS-1 or ZSM-5 molecular sieve can be preferably cylindrical, spherical or clover-shaped, more preferably cylindrical. Preferably, the nano TS-1 molecular sieve or ZSM-5 molecular sieve is mixed with a binder and prepared into TS-1 molecular sieve or ZSM-5 molecular sieve of different shapes by a molding machine. The above-mentioned binder is preferably silica sol, and the mass ratio of the nano molecular sieve to the binder is preferably 50-95:10-30, more preferably 60-80:15-25. There is no special requirement for the molding method of the molding machine, and the conventional method in the art can be used, such as using an extrusion molding machine to prepare a cylindrical TS-1 molecular sieve or ZSM-5 molecular sieve.

[0049] The preparation method of the nanomolecular sieve after metal ion modification molding preferably comprises the following steps: impregnating the molded nanomolecular sieve with a metal salt solution to obtain a metal ion modified nanomolecular sieve. The above-mentioned metal salt solution is preferably zinc nitrate, zinc sulfate, zinc acetate, copper nitrate or magnesium nitrate, more preferably zinc nitrate or magnesium nitrate; the concentration of the metal salt solution is preferably 0.01-10 mol / L, more preferably 0.05-5 mol / L; the metal loading is preferably 0.1-25%, more preferably 1%-15%; the solid-liquid ratio of the molded nanomolecular sieve and the metal salt solution is preferably 1:1-20, more preferably 1:3-10; the impregnation temperature is preferably 40-100°C, more preferably 50-80°C; the impregnation time is preferably 1-12h, more preferably 2-8h.

[0050] In this embodiment, the metal ion-modified nano molecular sieve in the second dehydration adsorption tower 32 preferably includes one of a metal ion-modified nano ZSM-5 molecular sieve adsorbent and a metal ion-modified nano TS-1 molecular sieve adsorbent, which can reduce the water content in R134a to ≤0.1ppm.

[0051] In this embodiment, the refrigerant R134a dehydration device 100 can be connected to an external R134a raw material supply source, or a raw material storage device 1 can be specially configured. The raw material storage device 1 is connected to the inlet of the adsorption unit 3. The raw material storage device 1 is used to store the R134a raw material and supply the R134a raw material to the adsorption unit 3.

[0052] Furthermore, a flow meter 2 is provided between the raw material storage device 1 and the inlet of the adsorption unit 3 to facilitate real-time detection of the supply flow of the R134a raw material.

[0053] In this embodiment, the raw material storage device 1 and the aforementioned product collection device 6 preferably use a collection bottle. This solution has no special restrictions on the size and material of the collection bottle, and conventional sizes and materials in the art can be used.

[0054] In this embodiment, Figure 1 As shown, in order to conveniently control the on-off and flow direction of the R134a raw material in the refrigerant R134a dehydration device 100, valves K1, K2, K3, K4 and K5 are respectively arranged between the raw material storage device 1 and the flow meter 2, between the first dehydration adsorption tower 31 and the second dehydration adsorption tower 32, between the outlet of the first dehydration adsorption tower 31 and the inlet of the moisture measuring device 5, between the outlet of the second dehydration adsorption tower 32 and the inlet of the moisture measuring device 5, and between the outlet of the filtration system 4 and the product collecting device 6. The valves K1, K2, K3, K4 and K5 are preferably solenoid valves.

[0055] In this embodiment, the filtration system 4 preferably uses an existing filter with a filter element precision of 0.1um, the purpose of which is to remove particulate impurities introduced by the adsorbent. The filter and the online moisture analyzer are both existing equipment, and the specific structure and working principle are not repeated here.

[0056] The above-mentioned refrigerant R134a dehydration device 100 can adsorb and dehydrate the R134a raw material with a water content of 10 to 100 ppm to obtain an R134a product with a water content of ≤0.1 ppm (w%). The following takes the water content of the R134a raw material as 70 ppm, the adsorbent arranged in the first dehydration adsorption tower 31 as an A-type molecular sieve adsorbent, and the adsorbent arranged in the second dehydration adsorption tower 32 as a metal ion-modified nano ZSM-5 molecular sieve adsorbent (also known as nano zeolite molecular sieve) as an example, and specifically describes the refrigerant R134a dehydration process and dehydration principle implemented by the above-mentioned refrigerant R134a dehydration device 100:

[0057] The R134a raw material with a water content of 70ppm is passed through the flow meter 2 into the adsorption unit 3. First, the first dehydration adsorption tower 31 uses the A-type molecular sieve adsorbent to reduce the water content from 70ppm to 15ppm, and then the second dehydration adsorption tower 32 uses the metal ion-modified nano ZSM-5 molecular sieve adsorbent to reduce the water content from 15ppm to ≤0.1ppm. After the moisture measuring device 5 detects and analyzes the qualified, the R134a product with a water content of ≤0.1ppm (w%) is finally obtained after being processed by the filtration system 4. Among them, the weight space velocity of the R134a raw material passing into the adsorption unit 3 is preferably 0.2~1.0h -1 The adsorption temperature of the first dehydration adsorption tower 31 is room temperature, such as 0 to 35°C, and the adsorption pressure is 0.1 to 0.5 MPa; the adsorption temperature of the second dehydration adsorption tower 32 is room temperature, such as 0 to 35°C, and the adsorption pressure is 0.1 to 1.0 MPa.

[0058] In actual operation, before the R134a raw material is introduced into the adsorption unit 3, the first dehydration adsorption tower 31 and the second dehydration adsorption tower 32 can be purged and vacuumed respectively by corresponding equipment. Generally, the purging temperature is 300-600°C and the time is 12-24 hours; the vacuuming time is 4-12 hours.

[0059] The above-mentioned refrigerant R134a dehydration device 100 can continuously perform two-stage adsorption dehydration treatment on the R134a raw material by arranging two-stage dehydration adsorption towers in series in the adsorption unit 3. The R134a raw material can be efficiently removed from the water in the R134a raw material after two-stage adsorption purification. Finally, after being tested and qualified by an online moisture analyzer, the R134a product with a water content of ≤0.1ppm (w%) can be collected. The above-mentioned refrigerant R134a dehydration device is suitable for deep dehydration of R134a, adopts adsorbent adsorption dehydration, and has the advantages of energy saving and consumption reduction.

[0060] In addition, nano-zeolite molecular sieves have rich pore structures and large specific surface areas. After being modified with metal ions, the electrostatic field effect in the zeolite pores is enhanced, the hydrophilicity is improved, and it is more conducive to the adsorption and removal of water in R134a.

[0061] The dehydration effect of the refrigerant R134a dehydration device 100 is verified in combination with the embodiments and comparative examples below:

[0062] Example 1

[0063] use Figure 1 The refrigerant R134a dehydration device 100 shown absorbs and removes water from the R134a raw material, and the water content in the R134a raw material is 70 ppm.

[0064] The adsorbent in the first dehydration adsorption tower 31 is 3A molecular sieve.

[0065] The adsorbent in the second dehydration adsorption tower 32 is a nano ZSM-5 molecular sieve modified with zinc nitrate; the preparation method of the nano ZSM-5 molecular sieve modified with zinc nitrate is as follows: a formed nano ZSM-5 molecular sieve with a silicon-aluminum ratio of 30 and a grain size of 50 nm is mixed with a zinc nitrate solution with a molar concentration of 1.0 mol / L (solid-liquid ratio of 1:4), immersed at 80°C for 6 hours, dried at 110°C for 12 hours after suction filtration, and calcined at 540°C for 6 hours to obtain a nano ZSM-5 molecular sieve adsorbent modified with zinc nitrate.

[0066] The adsorbent in the adsorption unit 3 is activated by using the purge unit 7 and the vacuum unit 8. The purge gas for the first dehydration adsorption tower 31 and the second adsorption and dehydration adsorption tower 4 is high-purity nitrogen with a purity of 99.999%, a temperature of 400°C, and a purge time of 24h. The first dehydration adsorption tower 31 and the second adsorption and dehydration adsorption tower 4 are vacuumed for 4h and then cooled to room temperature, such as 0-35°C.

[0067] R134a raw material was heated to 0.6h -1 The R134a is passed into the first dehydration adsorption tower 31 at a weight space velocity, and the first stage of adsorption and dehydration is carried out at normal temperature and pressure. After the first stage of adsorption and dehydration, the R134a enters the second dehydration adsorption tower 32, and the second stage of adsorption and dehydration is carried out at normal temperature and pressure to obtain the dehydrated R134a product.

[0068] Example 2

[0069] The R134a raw material is subjected to adsorption and dehydration according to the method of Example 1, except that the adsorbent in the second dehydration adsorption tower 32 is a nano ZSM-5 molecular sieve modified with copper nitrate.

[0070] Example 3

[0071] The R134a raw material is subjected to adsorption and dehydration according to the method of Example 1, except that the adsorbent in the second dehydration adsorption tower 32 is a nano ZSM-5 molecular sieve modified with magnesium nitrate.

[0072] Example 4

[0073] The R134a raw material is subjected to adsorption and dehydration according to the method of Example 1, except that the adsorbent in the second dehydration adsorption tower 32 is a nano ZSM-5 molecular sieve modified with zinc sulfate.

[0074] Example 5

[0075] The R134a raw material is subjected to adsorption and dehydration according to the method of Example 1, except that the adsorbent in the second dehydration adsorption tower 32 is a nano ZSM-5 molecular sieve modified with zinc acetate.

[0076] Comparative Example 1

[0077] Compared with the refrigerant R134a dehydration device 100 used in Example 1, the adsorption dehydration device used in Comparative Example 1 has only the first dehydration adsorption tower 31 but no second dehydration adsorption tower 32. The water content in the R134a raw material is 70 ppm.

[0078] The adsorbent in the first dehydration adsorption tower 31 is 3A molecular sieve.

[0079] The adsorbent in the adsorption unit 3 is activated by using the purge unit 7 and the vacuum unit 8. The purge gas for the first dehydration adsorption tower 31 is high-purity nitrogen with a purity of 99.999%, the temperature is 400°C, and the purge time is 24h. The first dehydration adsorption tower 31 is vacuumed for 4h and then cooled to room temperature, such as 0-35°C.

[0080] R134a raw material was heated to 0.6h -1 The weight space velocity is passed into the first dehydration adsorption tower 31, and adsorption and dehydration are carried out under normal temperature and pressure conditions to obtain the dehydrated R134a product.

[0081] Comparative Example 2

[0082] The R134a raw material is subjected to adsorption and dehydration according to the method of Comparative Example 1, except that the adsorbent in the first dehydration adsorption tower 31 is 5A molecular sieve.

[0083] The water content in the R134a products after dehydration in Examples 1 to 5 and Comparative Examples 1 and 2 was detected by an online moisture analyzer, and the results are listed in Table 1.

[0084] Table 1 Water content in R134a products after adsorption dehydration in Examples 1 to 5 and Comparative Examples 1 and 2

[0085]

[0086] As can be seen from Table 1, the refrigerant R134a dehydration device 100 with a two-stage dehydration adsorption tower provided in this embodiment is used to adsorb and dehydrate the R134a raw material, which can efficiently remove water from R134a and obtain an R134a product with a water content of ≤0.1ppm.

[0087] Embodiment 2

[0088] like Figure 2 As shown, this embodiment provides a refrigerant R134a dehydration device 100, which is further provided with a purge unit 7 and a vacuum unit 8 on the basis of the first embodiment, the outlet of the purge unit 7 is connected to the inlet of the first dehydration adsorption tower 31 and the inlet of the second dehydration adsorption tower 32; the inlet of the vacuum unit 8 is connected to the inlet of the first dehydration adsorption tower 31 and the inlet of the second dehydration adsorption tower 32.

[0089] In this embodiment, Figure 2 As shown, the vacuum unit 8 includes a vacuum buffer tank 81, a vacuum pump 82 and an exhaust gas treatment system 83 which are connected in sequence. The inlet of the vacuum buffer tank 81 is connected to the inlet of the first dehydration adsorption tower 31 and the inlet of the second dehydration adsorption tower 32. The vacuum buffer tank 81 is also directly connected to the exhaust gas treatment system 83. The exhaust gas treatment system 83 adopts existing technology, such as an exhaust gas processor of the model Hercules Mini, and its specific structure and working principle are not repeated here.

[0090] Based on the above scheme, Figure 2 As shown, in this embodiment, valves K6, K7, K8, K9, K10 and K11 are respectively arranged between the outlet of the purge unit 7 and the inlet of the first dehydration adsorption tower 31, between the outlet of the purge unit 7 and the inlet of the second dehydration adsorption tower 32, between the inlet of the vacuum buffer tank 81 and the inlet of the first dehydration adsorption tower 31, between the inlet of the vacuum buffer tank 81 and the inlet of the second dehydration adsorption tower 32, between the vacuum buffer tank 81 and the tail gas treatment system 83, and between the vacuum pump 82 and the tail gas treatment system 83. Valve K6, valve K7, valve K8, valve K9, valve K10 and valve K11 are preferably solenoid valves.

[0091] The refrigerant R134a dehydration method implemented based on the refrigerant R134a dehydration device 100 comprises the following steps:

[0092] The R134a raw material with a water content of 70ppm is passed through the flow meter 2 into the adsorption unit 3. First, the first dehydration adsorption tower 31 uses the A-type molecular sieve adsorbent to reduce the water content from 70ppm to 15ppm, and then the second dehydration adsorption tower 32 uses the metal ion-modified nano ZSM-5 molecular sieve adsorbent to reduce the water content from 15ppm to ≤0.1ppm. After the moisture measuring device 5 detects and analyzes the qualified, the R134a product with a water content of ≤0.1ppm (w%) is finally obtained after being processed by the filtration system 4. Among them, the weight space velocity of the R134a raw material passing into the adsorption unit 3 is preferably 0.05~1.2h -1 , more preferably 0.2 to 0.8 h -1 The adsorption temperature of the first dehydration adsorption tower 31 is room temperature, such as 0 to 35°C, and the adsorption pressure is 0.1 to 0.5 MPa; the adsorption temperature of the second dehydration adsorption tower 32 is room temperature, such as 0 to 35°C, and the adsorption pressure is 0.1 to 1.0 MPa.

[0093] In actual operation, before the R134a raw material is introduced into the adsorption unit 3, the first dehydration adsorption tower 31 and the second dehydration adsorption tower 32 of the adsorption unit 3 are purged and vacuumed by the purge unit 7 and the vacuum unit 8, respectively, so as to activate the adsorbent in the first dehydration adsorption tower 31 and the second dehydration adsorption tower 32. The purge gas for the first dehydration adsorption tower 31 and the second adsorption dehydration adsorption tower 4 is a high-purity nitrogen gas with a purity of 99.999%, the purge temperature is 300-500°C, the purge time is 18-32h, and more preferably 24-28h. The vacuuming time for the first dehydration adsorption tower 31 and the second adsorption dehydration adsorption tower 4 is preferably 2-8h, and more preferably 4-6h.

[0094] The above-mentioned refrigerant R134a dehydration device 100 can continuously perform two-stage adsorption dehydration treatment on the R134a raw material by arranging two-stage dehydration adsorption towers in series in the adsorption unit 3. The R134a raw material can be efficiently removed from the water in the R134a raw material after two-stage adsorption purification. Finally, after being tested and qualified by an online moisture analyzer, the R134a product with a water content of ≤0.1ppm (w%) can be collected. The above-mentioned refrigerant R134a dehydration device is suitable for deep dehydration of R134a, adopts adsorbent adsorption dehydration, and has the advantages of energy saving and consumption reduction.

[0095] The present invention uses specific examples to illustrate the principle and implementation of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A refrigerant R134a dehydration device, characterized in that: include: An adsorption unit, comprising at least two dehydration adsorption towers arranged in series along the flow direction of the raw material, so as to perform at least two-stage adsorption and dehydration on the R134a raw material in sequence; a filtration system having an inlet communicating with an outlet of the adsorption unit; A product collection device having an inlet communicating with an outlet of the filtration system.

2. The refrigerant R134a dehydration device according to claim 1, characterized in that: It also includes a moisture measuring device, and the outlet of any one of the dehydration adsorption towers is connected to the moisture measuring device, and the moisture measuring device is used to detect the water content of the outlet product of any one of the dehydration adsorption towers.

3. The refrigerant R134a dehydration device according to claim 2, characterized in that: It also includes a purge unit, and the inlet of any one of the dehydration adsorption towers is connected to the outlet of the purge unit.

4. The refrigerant R134a dehydration device according to claim 2, characterized in that: It also includes a vacuum unit, and the inlet of any one of the dehydration adsorption towers is connected to the vacuum unit.

5. The refrigerant R134a dehydration device according to claim 4, characterized in that: The vacuum unit comprises a vacuum buffer tank, a vacuum pump and an exhaust gas treatment system which are connected in sequence. The inlet of the vacuum buffer tank is connected to the inlet of any one of the dehydration adsorption towers, and the vacuum buffer tank is also directly connected to the exhaust gas treatment system.

6. The refrigerant R134a dehydration device according to any one of claims 2 to 5, characterized in that: The adsorption unit comprises a first dehydration adsorption tower and a second dehydration adsorption tower which are sequentially arranged in series along the flow direction of the raw material, wherein: The adsorbent disposed in the first dehydration adsorption tower includes a type A molecular sieve adsorbent and / or a modified type A molecular sieve adsorbent; The adsorbent arranged in the second dehydration adsorption tower includes a metal ion-modified nano ZSM-5 molecular sieve adsorbent and / or a metal ion-modified nano TS-1 molecular sieve adsorbent.

7. The refrigerant R134a dehydration device according to any one of claims 1 to 5, characterized in that: It also includes a raw material storage device connected to the inlet of the adsorption unit, and the raw material storage device is used to store and provide the R134a raw material to be dehydrated to the adsorption unit.

8. The refrigerant R134a dehydration device according to claim 7, characterized in that: Also included is a flow meter connected between the inlet of the adsorption unit and the raw material storage device.

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