Non-flammable mixed refrigerant capable of reducing greenhouse effect and use thereof

Abstract

Provided are a mixed refrigerant that is non-flammable and capable of reducing the greenhouse effect, and the use thereof. The mixed refrigerant comprises the following components in mass fractions: 10%-30% of R134a, 5%-70% of R1234ze(E), and 18%-65% of R1234yf. The mixed refrigerant of the present invention, in fitting combination with the amount ranges of all the components, makes the refrigerant non-flammable, and the ODP thereof is 0, and the GWP thereof is no greater than 400. The mixed refrigerant can be used in a refrigeration system, has no ozone destructive power, reduces the greenhouse effect, has a lower temperature glide, and belongs to ternary azeotropic or nearly azeotropic refrigerants, which is beneficial to the stable operation of a refrigeration system. The mixed refrigerant of the present invention can also serve as a foaming agent or aerosol propellant, and has the advantages of being non-flammable, having a low ozone destruction index, and being environmentally friendly and safe and reliable.

Claims

1. A mixed refrigerant consisting of, by mass fraction, 10-3025% of R134a, 5-70% of R1234ze(E), and 18-65% of R1234yf, wherein the mixed refrigerant has an ODP of 0 and a GWP of less than or equal to 400.

2. The mixed refrigerant according to claim 1, wherein the mixed refrigerant is non-flammable and azeotropic or near-azeotropic.

3. The mixed refrigerant according to claim 1, wherein the mixed refrigerant has an ODP of 0 and a GWP of less than or equal to 150.

4. A refrigeration system consisting of the mixed refrigerant according to claim 1.

5. A foaming agent consisting of the mixed refrigerant according to claim 1.

6. An aerosol propellant consisting of the mixed refrigerant according to claim 1.

Description

DETAILED DESCRIPTION

(1) The technical solutions of the present disclosure will be further illustrated by way of the following embodiments. It should be understood by those skilled in the art that these embodiments are only intended to aid the understanding of the present disclosure and should not 30 to be considered as limitation thereto.

Example 1

(2) In this example, a mixed refrigerant which comprised, by mass fraction, 11.3% of R134a, 69.8% of R1234ze(E) and 18.9% of R1234yf was provided.

Example 2

(3) In this example, a mixed refrigerant which comprised, by mass fraction, 10.1% of R134a, 54.5% of R1234ze(E) and 35.4% of R1234yf was provided.

Example 3

(4) In this example, a mixed refrigerant which comprised, by mass fraction, 10% of R134a, 34% of R1234ze(E) and 56% of R1234yf was provided.

Example 4

(5) In this example, a mixed refrigerant which comprised, by mass fraction, 22% of R134a, 48% of R1234ze(E) and 30% of R1234yf was provided.

Example 5

(6) In this example, a mixed refrigerant which comprised, by mass fraction, 30% of R134a, 49% of R1234ze(E) and 21% of R1234yf was provided.

Example 6

(7) In this example, a mixed refrigerant which comprised, by mass fraction, 30% of R134a, 5% of R1234ze(E), and 65% of R1234yf was provided.

Example 7

(8) In this example, a mixed refrigerant which comprised, by mass fraction, 10% of R134a, 25% of R1234ze(E) and 65% of R1234yf was provided.

(9) Under the air conditioning test conditions of ARI Standard 520: evaporation temperature 7.2° C., condensation temperature 54.4° C., superheat temperature 11.1° C., undercooling temperature 8.3° C. and compressor isentropic efficiency 0.8, the environmental parameters, physical properties and thermal properties of R134a and the mixed refrigerants in Examples 1-7 were measured and results are listed in Table 1.

(10) TABLE-US-00001 TABLE 1 Example Example Example Example Example Example Example 1 2 3 4 5 6 7 R134a ODP 0 0 0 0 0 0 0 0 GWP 147 132 130 286 390 390 130 1300 Molecular 112.54 112.7 112.71 111.16 110.15 110.15 112.71 102.03 weight g/mol Evaporating 296.86 308.6 337.45 324.79 327.56 402.18 353.84 376.84 pressure kPa Condensing 1132.54 1140.49 1198.21 1195.48 1221.62 1445.42 1242.05 1475.82 pressure kPa Exhaust 66.8 65.9 65.2 66.7 67.61 68.23 65.04 74.8 temperature ° C. Temperature 0.55 0.94 1.58 1.17 1.05 0.66 1.72 — glide ° C. COP* 1.03 1.04 1.05 1.05 1.11 1.03 1.06 1 Cooling 0.91 0.89 0.87 0.9 0.82 0.87 0.86 1 capacity* Volume 0.79 0.8 0.86 0.85 0.86 1.01 0.90 1 cooling capacity* Remarks: * in Table 1 indicates relative values of various parameters compared to the corresponding value of R134a, wherein COP is Coefficient of Performance.

(11) It can be seen from Table 1 that the mixed refrigerants as prepared in Examples 1-7 had an ODP of 0, a GWP of less than or equal to 400 and a temperature glide of less than 1° C. or close to 1° C. They belonged to azeotropic or near-azeotropic refrigerants, which were beneficial to the stable operation of the system. The evaporating pressure and condensing pressure of the mixed refrigerants were equivalent to those of R134a, and they can be directly used to replace R134a in systems without great modification. Compared with R134a, the cooling capacity and volume cooling capacity of the mixed refrigerants were both lower than those of R134a by about 10%; COP was 3-11% higher than that of R134a, and the exhaust temperature was also lower, which was beneficial to reduce the exhaust temperature of the compressor.

(12) The explosion limits of the mixed refrigerants in Examples 1-7, R600a (R600a was used to verify the accuracy of equipment used in the flammability test), R1234ze(E) and R1234yf were measured according to the ASHRAE 34 standard. The experiments were performed in a 12 L round bottom flask. The ignition source was the induction spark between two electrodes with an alternating current of 30 mA, 15 KV, and a spark duration of 0.4 s. The electrodes were L-shape, made of tungsten and had a diameter of 1 mm. The two electrodes were 6.4 mm apart. The electrodes were mounted at a height of ⅓ from the bottom of the bottle. The angle of flame propagation was determined by observation and was used to determine the flammability. If the angle between the center of the electrodes and the flame frontier on the flask wall was less than 90 degree, the refrigerant was non-flammable; if the angle was greater than 90, it was flammable. The test results are shown in Table 2, wherein LFL represents the lower flammable limit, UFL represents the upper flammable limit and if there are no LFL or UFL values, the refrigerant is not flammable.

(13) TABLE-US-00002 TABLE 2 LFL UFL Refrigerant (v %) (v %) Notes R600a 1.8 8.5 R1234ze(E) 7 9.5 R1234yf 6.2 12.3 Example 1 NA NA None-flammable Example 2 NA NA None-flammable Example 3 NA NA None-flammable Example 4 NA NA None-flammable Example 5 NA NA None-flammable Example 6 NA NA None-flammable Example 7 NA NA None-flammable

(14) Table 2 shows that the mixed refrigerants of the present disclosure were non-flammable. The mixed refrigerants of Examples 1-7 were charged into a pressure resistant container with an observation window. The temperature in the container was kept at 25° C. and the mixed refrigerant was in a vapor-liquid equilibrium state. The initial vapor pressure in the container was measured, and then the refrigerant in the container was discharged slowly in order to keep the temperature constant until 50% weight percent of the mixed refrigerant was discharged. At this time, a part of liquid was still present in the container. The vapor pressure was measured again. Changes in pressure values before relief ant that after relief are shown in Table 3.

(15) TABLE-US-00003 TABLE 3 Pressure Pressure after Change in before 50% relief pressure Refrigerant relief (kPa) (kPa) (%) Example 1 630.62 588.5 6.68 Example 2 660.94 626.12 5.27 Example 3 653.57 647 1 Example 4 736.52 675.36 8.3 Example 5 623.76 612.75 1.7 Example 6 704.53 703.44 0.2 Example 8 667.14 662.65 0.7

(16) Table 3 shows that pressure changes before and after relief were less than 10% and that the mixed refrigerants were azeotropic or near-azeotropic.

(17) The embodiments above are used to illustrate the mixed refrigerants of the present disclosure and use thereof; however, the present disclosure is not limited to the above embodiments, and it does not mean that the present disclosure must rely on the above embodiments to be implemented. It should be understood by those skilled in the art that any improvements of the present disclosure, the equivalent replacement of the raw materials of the present disclosure, the addition of auxiliary components and the selection of specific means etc. will all fall within the scope of protection and disclosure of the present disclosure.