An environmentally friendly high-temperature heat pump non-azeotropic mixed working medium containing cis-1,1,1,4,4,4-hexafluoro-2-butene

Abstract

The application discloses an environmentally-friendly high-temperature heat pump non-azeotropic mixed working medium containing cis-1,1,1,4,4,4-hexafluoro-2-butene, the mixed working medium comprises a first component cis-1,1,1,4,4,4-hexafluoro- 2-butene (R1336mzz(Z)) and a second component 3,3,3-trifluoropropene (R1243zf), and optionally one of the third components trans-1-chloro-3,3,3-trifluoropropene (R1233zd(E)), cis-1-chloro-2,3,3,4-tetrafluoropropene (R1224yd(Z)), trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) or cis-1,3,3,3-tetrafluoropropene (R123 4ze(Z)). The mixed working medium GWP < 2, and meets the environmental performance requirements. Under the design condition, the COP h The application can replace R245fa and be used in industrial waste heat recovery, coal chemical industry waste heat utilization and high-temperature hot water preparation and the like.

Description

Technical Field

[0001] This invention belongs to the field of mixed heat pump working fluid technology, and particularly relates to an environmentally friendly high-temperature heat pump non-azeotropic mixed working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, which can be used in industrial waste heat recovery, high-temperature hot water preparation and steam heat pump applications. Background Technology

[0002] Coal chemical industry is a concentrated producer of high-grade waste heat. In typical processes such as coal-to-methanol, coal-to-olefins, and coal-to-natural gas, stages such as shift converter cooling, low-temperature methanol wash tail gas condensation, and pressure swing adsorption regeneration generate a large amount of low-grade waste heat (60–90°C). Due to the performance limitations of heat pump working fluids, this waste heat has long been discharged into the atmosphere in the form of circulating water, causing serious energy waste and exacerbating carbon emissions. If this waste heat could be raised to above 100°C using high-temperature heat pumps for process heating, steam tracing, or preheating boiler feedwater, the overall energy consumption of the coal chemical system could be significantly reduced, which is of great significance for achieving the industry's energy conservation and carbon reduction goals. However, the existing high-temperature heat pump working fluid R245fa is constrained by its high GWP and accelerated phase-out process. There is an urgent need to develop a low-GWP, high-COP working fluid with moderate calorific value per unit volume that can be directly applied to coal chemical waste heat recovery scenarios.

[0003] R245fa (1,1,1,3,3-pentafluoropropane, CAS No.: 460-73-1) is one of the most widely used working fluids in the field of high-temperature heat pumps. It has good thermodynamic properties and chemical stability, with a critical temperature of 154°C, which can meet the needs of high-temperature heat pumps with condensation temperatures below 120°C. However, R245fa has a high global warming potential (GWP) of 858, and has been included in the controlled reduction list of the Kigali Amendment, making it difficult to align with the global environmental policy orientation of low-carbon development. In recent years, a series of low-environmental-load fluorocarbons (HFOs) have been proposed as alternative working fluids, but their overall performance still has significant limitations. For example, although R1233zd(E) can improve the system COP, its volumetric heating capacity is significantly reduced; R1234ze(E) has a high condensing pressure under high-temperature conditions, limiting the overall system efficiency; and although R600 has a high volumetric heating capacity, the system COP decreases.

[0004] R1336mzz(Z) (cis-1,1,1,4,4,4-hexafluoro-2-butene, CAS No.: 692-49-9) is currently recognized as the most promising alternative to R245fa, with a GWP of only 2, a safety class of A1, a critical temperature of 171.3°C, and the ability to provide heating at temperatures above 160°C. However, the volumetric heating capacity (VHC) of R1336mzz(Z) is only 57-62% of that of R245fa, resulting in a higher compressor displacement requirement and higher system cost. Since different working fluids have unique properties, their advantages and disadvantages can be balanced through complementary methods. Mixing several working fluids can yield a mixed working fluid that meets the required conditions. Furthermore, non-azeotropic working fluids composed of different working fluids exhibit temperature glide during boiling, which can make the system cycle closer to the Lorenz cycle, thereby improving cycle efficiency.

[0005] Regarding the research on R1336mzz(Z) in mixed working fluids, patent application CN106398650A discloses a ternary mixed working fluid for high-temperature heat pumps in coal mine geothermal utilization. Specifically, it discloses various binary and ternary mixed working fluids composed of R1336mzz(Z) with R134a, R227ea, R236ea, R245fa, and HFE-type working fluids. These are suitable for medium- and high-temperature heat pumps with an evaporation temperature of 40°C and a condensation temperature of 90°C, with a COP of approximately 5.2 to 5.8. However, the second component used is a high GWP HFC-type substance (R134a has a GWP of 1300, and R227ea has a GWP of 3500). Patent application CN115353862A discloses an environmentally friendly working fluid suitable for high-temperature heat pump systems. Specifically, it discloses a ternary mixed working fluid of R1233zd(E) / R1336mzz(Z) / ethylene oxide. Under the conditions of evaporation at 50°C and condensation at 100°C, the COP can reach 109.7% of R245fa. However, ethylene oxide is toxic and flammable, posing a significant safety hazard. Patent application CN118879277A discloses an environmentally friendly high-temperature non-azeotropic working fluid and its application. Specifically, it discloses a ternary mixed working fluid of R600a / R1336mzz(Z) / a third component (R1224yd(Z), R1233zd(E), or R1234ze(Z)). Under conditions of an average evaporation temperature of 58°C and an average condensation temperature of 104°C, its COP is 1.14 to 1.23 times that of R245fa, and its GWP is <3. However, R600a (isobutane) is an A3-class highly flammable working fluid, requiring explosion-proof facilities for industrial applications, resulting in high engineering costs. Patent application CN112020267A discloses an environmentally friendly heat pipe working fluid, specifically disclosing various binary mixed working fluids represented by R1234ze(Z) / R1336mzz(E), used in gravity heat pipe systems (evaporation temperature approximately 35°C).

[0006] R1243zf (3,3,3-trifluoropropylene, CAS No.: 677-21-4) is a chlorine-free HFO working fluid with a gas permeable (GWP) of <1, a safety class of A2 (weakly flammable), a normal boiling point of -25.4°C, a critical temperature of 103.8°C, and a critical pressure of 3.55 MPa. Its boiling point is approximately 59 K lower than that of R1336mzz(Z), and when mixed, they form a non-azeotropic system with significant temperature glide. Based on the temperature matching effect (Lorenz cycle effect) of non-azeotropic working fluids in countercurrent heat exchangers, adding an appropriate amount of R1243zf can effectively increase the volumetric heating capacity of the R1336mzz(Z) base working fluid without significantly reducing safety. Simultaneously, it improves the heat exchange matching between the evaporator side and the heat source fluid through temperature glide, thereby enhancing the overall cycle efficiency.

[0007] Existing patents for mixed working fluids based on R1336mzz(Z) suffer from several drawbacks, including high GWP, the presence of flammable or toxic components, limited safety levels, low design operating temperatures, and a failure to effectively address the core weakness of low heating capacity per unit volume of R1336mzz(Z). Currently, there is no high-temperature heat pump mixed working fluid solution based on a system combining R1336mzz(Z) and R1243zf (3,3,3-trifluoropropylene) that balances low GWP, high safety, high COP, and moderate VHC. Summary of the Invention

[0008] To overcome the shortcomings of the prior art, the present invention aims to provide an environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, by using the first component cis-1,1,1,4,4,4-hexafluoro-2-butene ( R1336mzz(Z) is mixed with the second component 3,3,3-trifluoropropylene (R1243zf) and an optional third component (R1233zd(E), R1224yd(Z), R1234ze(E or R1234ze(Z)) in a specific mass ratio. This mixture can significantly improve the volumetric heating capacity (VHC) and improve the temperature matching between the evaporator and condenser sides while maintaining a total GWP of less than 2 and a high safety level. It has the comprehensive advantages of having a COP superior to R245fa, a VHC higher than R1336mzz(Z), a moderate temperature glide on the evaporator side, and the ability to directly replace R245fa in high-temperature heat pump applications such as waste heat recovery in coal chemical industry.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising a first component cis-1,1,1,4,4,4-hexafluoro-2-butene R1336mzz(Z) and a second component 3,3,3-trifluoropropylene R1243zf, wherein, by mass percentage, R1336mzz(Z):R1243zf = (62-94%):(6-38%).

[0010] An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising a first component cis-1,1,1,4,4,4-hexafluoro-2-butene R1336mzz(Z) and a second component 3,3,3-trifluoropropylene R1243zf, wherein, by mass percentage, R1336mzz(Z):R1243zf = (73-85%): (15-27%).

[0011] In one embodiment, the sum of the percentages of R1336mzz(Z) and R1243zf is 100%, meaning that the mixed working fluid of the present invention can consist of only the first component and the second component.

[0012] The mixed working fluid also includes a third component, which is selected from trans-type... 1 chlorine 3,3,3 Trifluoropropylene R1233zd(E), cis- 1 chlorine 2 ,3,3,4 Tetrafluoropropylene R1224yd(Z), trans- 1,3,3,3 Tetrafluoropropylene R1234ze(E) or cis- 1,3,3,3 One of the tetrafluoropropylene R1234ze(Z), in which the mass percentages of each component are: R1336mzz(Z): 62-84%; R1243zf: 8-25%; and the third component: 1-25%.

[0013] When the third component is R1233zd(E), the mass percentages of each component are: R1336mzz(Z): 62-84%; R1243zf: 13-25%; third component: 1-24%.

[0014] When the third component is R1224yd(Z), the mass percentages of each component are: R1336mzz(Z): 68-84%; R1243zf: 13-25%; R1224yd(Z): 1-18%.

[0015] When the third component is R1234ze(E), the mass percentages of each component are: R1336mzz(Z): 67-84%; R1243zf: 8-24%; R1234ze(E): 1-25%.

[0016] When the third component is R1234ze(Z), the mass percentages of each component are: R1336mzz(Z): 68-84%; R1243zf: 12-25%; R1234ze(Z): 1-19%.

[0017] In one embodiment, the sum of the percentages of the first component, the second component, and the third component is 100%, meaning that the mixed working fluid of the present invention may consist only of the first component, the second component, and the third component.

[0018] The preparation method of the mixed working fluid of the present invention is simple. Specifically, the components are directly physically mixed in the liquid phase according to the mass ratio.

[0019] Compared with the prior art, the present invention has the following advantages: This invention achieves a non-azeotropic blend of a non-flammable high-temperature working fluid R1336mzz(Z) and a low-boiling-point HFO working fluid R1243zf, and optionally introduces R1233zd(E), R1224yd(Z), R1234ze(E), or R1234ze(Z) as a third component to adjust the thermodynamic properties. It utilizes the temperature glide effect (Lorenz cycle effect) of the non-azeotropic mixture to improve heat transfer matching on the evaporation side. Simultaneously, by precisely controlling the distribution ratio of each component, the mixture is maintained within the non-flammable concentration range. Thus, while ensuring safe use in industrial settings, it achieves synergistic optimization of improved COP, significantly reduced VHC, and low GWP, offering the following technical advantages: 1. The environmentally friendly high-temperature heat pump non-azeotropic working fluid of this invention, wherein R1336mzz(Z) has a high critical temperature (171.4℃) and excellent safety (A1 grade non-flammable), and has a high COP and low condensing pressure under high condensing temperature conditions, but its volumetric heating capacity is low (only about 56% of R245fa), resulting in a significant increase in the required compressor displacement. R1243zf has a low standard boiling point (-25.4℃) and a high saturated vapor pressure, which can significantly improve the volumetric heating capacity of the mixture. After the two are non-azeotropically compounded in a certain proportion, the disadvantage of insufficient volumetric heating capacity of R1336mzz(Z) can be compensated for while maintaining a high COP.

[0020] 2. In the mixed working fluid described in this invention, R1233zd(E), R1224yd(Z), R1234ze(E), and R1234ze(Z) have high COP and can be used as a third component to further adjust the thermodynamic properties, achieving COP and q under different application conditions. v The best balance.

[0021] 3. Because the saturation pressures of the components in this invention differ significantly at the same temperature, they exhibit temperature glide characteristics during evaporation and condensation after mixing. This non-azeotropic characteristic allows the system cycle to approximate a Lorenz cycle, reducing the average heat transfer temperature difference between the working fluid and the external fluid in the heat exchanger, thereby reducing irreversible losses and improving cycle efficiency.

[0022] 4. All components of the mixed working fluid described in this invention are low-GWP environmentally friendly working fluids with an ODP of 0. The overall GWP of the mixture is less than 2, far lower than that of R245fa (GWP=858), meeting the requirements for reducing hydrofluorocarbons. Although R1243zf is an A2-class weakly flammable working fluid, this invention, based on the ASHRAE 34-2019 standard and referring to the theory of flammability estimation of mixed refrigerants, calculates the critical explosion suppression concentration for the representative proportions of this invention. By controlling the mass fraction of R1243zf (not exceeding 38% in binary systems and not exceeding 25% in ternary systems), the volume fraction of R1243zf in the mixture is always kept within the non-flammable concentration range, allowing for safe use in industrial settings.

[0023] 5. The pressure ratio of the mixed working fluid described in this invention is on the same order of magnitude as that of R245fa, and it can be directly applied to compressor and heat exchanger systems designed for R245fa without major modifications to existing equipment, which helps to reduce replacement costs and accelerate engineering promotion. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments, so that those skilled in the art can better understand and implement the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. It should be understood that the specific embodiments are only used to explain the present invention, but the embodiments are not intended to limit the present invention.

[0025] The basic physical properties of each component in this invention are shown in Table 1.

[0026] Table 1 Basic physical properties of each component R245fa CF3CH2CHF2 15.0 154.1 858 R1336mzz(Z) CF3CH=CHCF3 33.4 171.3 2 R1243zf CF3CH=CH2 -25.4 103.8 <1 R1233zd(E) CF3CH=CHCl 18.3 166.5 1 R1224yd(Z) CF3CF=CHCl 14.6 155.5 <1 R1234ze(E) CF3CH=CHF(E) -19.0 109.4 <1 R1234ze(Z) CF3CH=CHF(Z) 9.7 150.1 <1 (Note: GWP values ​​are based on the 100-year timescale of the IPCC Fifth Assessment Report) A single-stage vapor compression cycle model was used to perform thermodynamic simulations of the above-mentioned mixed working fluid. The calculation conditions were: mean evaporation temperature (bubble point + dew point) 60–90°C, fixed temperature rise of 60K (mean condensation temperature = mean evaporation temperature + 60°C), superheat 5K, subcooling 5K, isentropic efficiency 0.70, and working fluid properties were calculated using REFPROP 10.0. Before the calculations, the critical temperature of each working fluid under each operating condition was verified to ensure that the condensation temperature was at least 10K lower than the critical temperature of the mixture (subcritical safety margin). Fluids exceeding this margin were not included in the examples.

[0027] The specific implementation method is as follows: Examples 1-4: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene comprises a first component, cis-1,1,1,4,4,4-hexafluoro-2-butene (R1336mzz(Z)), and a second component, 3,3,3-trifluoropropylene (R1243zf), with a mass percentage ratio of R1336mzz(Z):R1243zf = 85%:15%. This mixture is physically mixed in the liquid phase and used as the environmentally friendly high-temperature non-azeotropic working fluid. Examples 1-4 use different evaporation and condensation temperatures: evaporation temperatures of 60, 70, 80, and 90°C, and condensation temperatures of 120, 130, 140, and 150°C.

[0028] Example 5: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, wherein R1336mzz(Z) 80% and R1243zf 20% by mass percentage are physically mixed in the liquid phase to serve as the environmentally friendly high-temperature non-azeotropic working fluid.

[0029] Example 6: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, wherein R1336mzz(Z) 73% and R1243zf 27% by mass percentage are physically mixed in the liquid phase to serve as the environmentally friendly high-temperature non-azeotropic working fluid.

[0030] Example 7: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 62% R1336mzz(Z) and 38% R1243zf by mass percentage, is used as the environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase. Example 8: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, wherein R1336mzz(Z) 94% and R1243zf 6% by mass percentage are physically mixed in the liquid phase to serve as the environmentally friendly high-temperature non-azeotropic working fluid.

[0031] Example 9: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 15% R1243zf, and 1% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0032] Example 10: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 13% R1243zf, and 3% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0033] Example 11: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 75% R1336mzz(Z), 14% R1243zf, and 11% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0034] Example 12: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 65% R1336mzz(Z), 14% R1243zf, and 21% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0035] Example 13: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 65% R1336mzz(Z), 24% R1243zf, and 11% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0036] Example 14: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 62% R1336mzz(Z), 25% R1243zf, and 13% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0037] Example 15: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 62% R1336mzz(Z), 14% R1243zf, and 24% R1233zd(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0038] Example 16: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 15% R1243zf, and 1% R1224yd(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0039] Example 17: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 13% R1243zf, and 3% R1224yd(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0040] Example 18: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 82% R1336mzz(Z), 14% R1243zf, and 4% R1224yd(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0041] Example 19: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 68% R1336mzz(Z), 14% R1243zf, and 18% R1224yd(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0042] Example 20: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 68% R1336mzz(Z), 25% R1243zf, and 7% R1224yd(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0043] Example 21: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 15% R1243zf, and 1% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0044] Example 22: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 8% R1243zf, and 8% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0045] Example 23: An environmentally friendly high-temperature heat pump non-azeotropic mixture containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 80% R1336mzz(Z), 16% R1243zf, and 4% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic mixture after physical mixing in the liquid phase.

[0046] Example 24: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 72% R1336mzz(Z), 8% R1243zf, and 20% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0047] Example 25: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 72% R1336mzz(Z), 24% R1243zf, and 4% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0048] Example 26: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 67% R1336mzz(Z), 8% R1243zf, and 25% R1234ze(E) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0049] Example 27: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 15% R1243zf, and 1% R1234ze(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0050] Example 28: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 84% R1336mzz(Z), 12% R1243zf, and 4% R1234ze(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0051] Example 29: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 80% R1336mzz(Z), 15% R1243zf, and 5% R1234ze(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0052] Example 30: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 68% R1336mzz(Z), 13% R1243zf, and 19% R1234ze(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0053] Example 31: An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, comprising 68% R1336mzz(Z), 25% R1243zf, and 7% R1234ze(Z) by mass percentage, is used as an environmentally friendly high-temperature non-azeotropic working fluid after physical mixing in the liquid phase.

[0054] Comparative Examples 1-4: Using R245fa, a common working fluid in high-temperature heat pumps, different evaporation and condensation temperatures were selected. The evaporation temperatures were 60, 70, 80, and 90℃, and the condensation temperatures were 120, 130, 140, and 150℃, respectively.

[0055] Comparative Examples 5-8: Using pure working fluid R1336mzz(Z), different evaporation and condensation temperatures were selected, with evaporation temperatures of 60, 70, 80, and 90℃ and condensation temperatures of 120, 130, 140, and 150℃.

[0056] The sum of the mass percentages of all components in each of the above mixed working fluids is 100%. The preparation method of the above mixed working fluids is simply to physically mix the components in the liquid phase according to the specified mass ratio, without the need for special equipment.

[0057] The performance data for the comparative model are listed in Table 2.

[0058] Table 2 Comparative thermodynamic properties Note: q v Heat output per unit volume (kJ / m³) 3 ); P c P is the evaporation pressure (kPa). e The condensation pressure is (kPa).

[0059] Performance data for a typical embodiment are listed in Table 3.

[0060] Table 3 Thermal performance of typical embodiments Note: COP / COP R245fa To achieve the same COP as pure R245fa under the same operating conditions h The ratio; COP / COP R1336mzz To achieve the same COP as pure R1336mzz(Z) under the same operating conditions h The ratio.

[0061] As can be seen from Table 3: (1) Temperature comparison of binary systems (Examples 1-4): The same ratio R1336mzz(Z) / R1243zf=85 / 15 showed a stable COP advantage in the evaporation temperature range of 60-90°C. h From 4.098 (t) E =60°C) monotonically decreases to 3.498 (t) as the evaporation temperature increases. E =90°C), compared with Comparative Examples 1-4 (R245fa, COP=3.517→3.008) and Comparative Examples 5-8 (pure R1336mzz(Z), COP=3.573→3.083), COP / COP under each operating condition. R245faBoth remained between 1.163 and 1.165, COP / COP R1336mzz The values ​​were all between 1.061 and 1.147, indicating that the mixed formulation is effective over a wide temperature range, and the addition of R1243zf effectively improved the cycle efficiency through the non-azeotropic mixing effect.

[0062] (2) Comparison of binary systems with different R1243zf contents (Examples 1, 5, 6, 7, and 8, all t E =60°C): R1243zf content increased from 6% (Example 8, 94 / 6) to 15% (Example 1, 85 / 15), 20% (Example 5, 80 / 20), 27% (Example 6, 73 / 27), and 38% (Example 7, 62 / 38), COP h The concentration decreased from 4.098 to 3.688, but qv increased significantly from 2436 to 4327 kJ / m³. 3 This indicates that the R1243zf content affects q. v Significant impact—the more R1243zf, the more q v The higher the R1243zf content, the smaller the compressor displacement requirement. The temperature glide varies from 13.5 to 25.1 K depending on the R1243zf content, suitable for different heat exchanger design requirements.

[0063] (3) Comparison of the types of the third component in the ternary system (Examples 9, 16, 21, and 27, all 84 / 15 / 1, t E =60°C): Four embodiments containing R1233zd(E), R1224yd(Z), R1234ze(E), and R1234ze(Z) COP h The values ​​are 4.088, 4.087, 4.090, and 4.087 respectively; q v The values ​​are 3166, 3167, 3205, and 3174 kJ / m³, respectively. 3 The differences are small. This indicates that in regions with high R1336mzz(Z) content, the four tertiary components have little difference in their impact on thermodynamic properties, and all can be considered effective formulation options.

[0064] (4) Cross-comparison of R1243zf and R1233zd (E) content in the ternary system (Examples 11, 12, 13): ① Example 11 (75 / 14 / 11) and Example 12 (65 / 14 / 21): The R1243zf content was the same (14%), R1336mzz decreased by 10%, R1233zd increased by 10%, and COPh decreased from 4.009 to 3.946 ( (0.063), qv only increased from 3150 to 3206 kJ / m 3 (+56), the evaporation-side slip decreased from 19.5 K to 17.7 K ( 1.8 K). This indicates that R1233zd(E) mainly plays a role in reducing temperature glide, with limited impact on COP and qv. ② Example 12 (65 / 14 / 21) and Example 13 (65 / 24 / 11): The R1336mzz content was the same (65%), R1243zf increased by 10%, R1233zd decreased by 10%, and qv increased from 3206 kJ / m³ to 3706 kJ / m³ (+500), indicating that the R1243zf content has a significant effect on qv. v The impact was significant. ③ Example 11 (75 / 14 / 11) and Example 13 (65 / 24 / 11): The content of R1233zd was the same (11%), R1336mzz decreased by 10%, R1243zf increased by 10%, and COPh decreased from 4.009 to 3.912. The concentration of R1243zf is 0.097, but the qv increases significantly from 3150 to 3706 kJ / m³ (+556), and the evaporation-side slip increases from 19.5 K to 22.4 K (+2.9 K), further indicating that R1243zf is the key component for increasing qv, and sufficient R1243zf content should be maintained within the scope of claim 4.

[0065] (5) Scope boundary verification of each claim: Each embodiment at t E =60°C / t C At 120°C, COP / COP R245fa Both are not lower than 1.048, COP / COP R1336mzz All are not less than 1.032; the pressure ratio is 3.704 to 4.032, P c The Pa range is 1328.2–2437 kPa, compared to Comparative Example 1 (R245fa, P c =1930.4 kPa) is on the same order of magnitude, P e The Pa range is 329.4–658 kPa, compared to Comparative Example 1 (P e The pressure is close to 462.5 kPa, indicating that the mixed working fluid of the present invention can be directly used in compressor and heat exchanger systems designed for R245fa.

[0066] (6) All embodiments at t E =60°C / t C At 120°C, q v 2436–4327 kJ / m 3 (Binary) and 3008~3801 kJ / m 3 (Ternary), and pure R1336mzz(Z) (1761 kJ / m 3 Compared to R245fa (3141kJ / m), the improvement is 38-146%, and compared to R245fa (3141kJ / m). 3Compared to, it is basically equivalent to or better, making up for the q of R1336mzz(Z). v Shortcomings.

[0067] (7) The GWP of the mixed working fluid in all embodiments was less than 2 (GWP mix =The sum of the products of the mass fraction of each component and GWP), which is much lower than R245fa (GWP=858). R1243zf is A2 grade, but this invention controls the mass fraction of R1243zf (≤38wt% for binary systems, ≤25wt% for ternary systems) to ensure that the volume fraction of R1243zf in the mixture is always within the non-flammable concentration range. According to ASHRAE 34-2019 standard, and referring to the theory of mixed refrigerant flammability estimation (Takanzo model), the critical explosion suppression concentration of the representative ratio of this invention was calculated: taking the binary mixed refrigerant R1336mzz(Z) / R1243zf=62 / 38 (mass ratio) as an example, the corresponding volume fraction of R1243zf is about 46vol%, which is lower than the critical flammability limit of 47.75vol% for this binary system, and the mixture is in a non-flammable state. The volume fraction of R1243zf in the other embodiments was calculated using the same method and was within the non-flammable range. Therefore, the lower flammability limit of the non-azeotropic working fluid in this embodiment is significantly higher than that of pure R1243zf, and it can be used safely under standard industrial protective measures.

[0068] In summary, the environmentally friendly high-temperature non-azeotropic working fluid of the embodiment has excellent environmental performance, high safety and economy, and large temperature glide, and can be used as a new type of high-temperature heat pump mixing working fluid for long-term use.

Claims

1. An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene, characterized in that, It includes the first component, cis-1,1,1,4,4,4-hexafluoro-2-butene R1336mzz(Z), and the second component, 3,3,3-trifluoropropene R1243zf, with a mass percentage of R1336mzz(Z):R1243zf = (62-94%):(6-38%).

2. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 1, characterized in that, By mass percentage, R1336mzz(Z):R1243zf = (73-85%): (15-27%).

3. An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 1 or 2, characterized in that, The sum of the percentages of R1336mzz(Z) and R1243zf is 100%.

4. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 1, characterized in that, The mixed working fluid also includes a third component, which is selected from trans-type... 1 chlorine 3,3,3 Trifluoropropylene R1233zd(E), cis- 1 chlorine 2 ,3,3,4 Tetrafluoropropylene R1224yd(Z), trans- 1,3,3,3 Tetrafluoropropylene R1234ze(E) or cis- 1,3,3,3 One of the tetrafluoropropylene R1234ze(Z), in which the mass percentages of each component are: R1336mzz(Z): 62-84%; R1243zf: 8-25%; and the third component: 1-25%.

5. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 4, characterized in that, When the third component is R1233zd(E), the mass percentages of each component are: R1336mzz(Z): 62-84%; R1243zf: 13-25%; third component: 1-24%.

6. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 4, characterized in that, When the third component is R1224yd(Z), the mass percentages of each component are: R1336mzz(Z): 68-84%; R1243zf: 13-25%; R1224yd(Z): 1-18%.

7. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 4, characterized in that, When the third component is R1234ze(E), the mass percentages of each component are: R1336mzz(Z): 67-84%; R1243zf: 8-24%; R1234ze(E): 1-25%.

8. The environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to claim 4, characterized in that, When the third component is R1234ze(Z), the mass percentages of each component are: R1336mzz(Z): 68-84%; R1243zf: 12-25%; R1234ze(Z): 1-19%.

9. An environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene according to any one of claims 4 to 8, characterized in that, The sum of the percentages of the first component, the second component, and the third component is 100%.

10. The method for preparing the environmentally friendly high-temperature heat pump non-azeotropic working fluid containing cis-1,1,1,4,4,4-hexafluoro-2-butene as described in any one of claims 1 to 9, characterized in that, The components are physically mixed in the liquid phase according to their mass ratio to obtain the final product.

Images