A new refrigerant capable of replacing r290

Abstract

The application belongs to the technical field of refrigeration, heat pump and low boiling point power cycle, and discloses a novel refrigerant capable of replacing R290, which is a ternary mixture composed of hexafluoropropylene (R1216), propane (R290) and propylene (R1270), wherein the mass percentage concentration of hexafluoropropylene is 71-85%, the mass percentage concentration of propane is 5-25%, and the mass percentage concentration of propylene is 1-20%. The novel refrigerant provided by the application has an ODP value of zero and a GWP less than 5, has the characteristics of not destroying the ozone layer and having a small greenhouse effect, and has good environmental protection performance; and the flammability of the novel refrigerant is obviously weaker than that of R290, and the novel refrigerant has obvious advantages in safety. The thermodynamic performance of the novel refrigerant is equivalent to or even better than that of R290, and the novel refrigerant can completely replace R290 in refrigeration, heat pump and low boiling point power cycle systems, and has wide application prospects.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration, heat pump and low boiling point power cycle technology, specifically, it relates to a mixed refrigerant for replacing R290. Background Technology

[0002] Hydrocarbon refrigerants have regained industry attention due to their zero ozone potential (ODP), extremely low global warming potential (GWP), and excellent thermodynamic cycle performance. Propane (R290) is a typical hydrocarbon refrigerant. Its saturated vapor pressure, latent heat of vaporization, viscosity coefficient, and thermal conductivity in both saturated liquid and gaseous states are superior to dichlorofluoromethane (R22). It requires only 30%–40% of the charge of R22, and has lower exhaust temperature and pressure, making it suitable for small-scale refrigeration equipment. However, R290 has a flash point of 468°C and an explosive limit of 2.1%–9.5% (volume fraction). This flammability and explosiveness label is the biggest obstacle to its large-scale application. Currently, only by solving the combustion and explosion problems and alleviating public fears can the widespread application of R290 be truly realized.

[0003] Due to the inherent contradictions between the environmental, flammability, and thermodynamic properties of the refrigerant, pure refrigerants often cannot meet current requirements. Compromising on flammability, environmental friendliness, and thermodynamic performance, using mixed refrigerants is one way to solve the current problems. However, a perfect alternative has not yet been found. Overcoming the shortcomings of existing technologies and finding a refrigerant with good thermodynamic properties and environmental friendliness to replace R290 has become an urgent problem to be solved. Summary of the Invention

[0004] To address the technical problem of poor safety performance of R290 refrigerant, this invention provides a novel refrigerant that can replace R290. This novel refrigerant has an ODP value of zero and a GWP of less than 5, and features that it does not damage the ozone layer and has a small impact on the greenhouse effect, thus exhibiting good environmental performance. Its thermodynamic properties are comparable to or even better than those of R290, making it a complete replacement for R290 in refrigeration, heat pump, and low-boiling-point power cycle systems. More importantly, its flammability is significantly weaker than that of R290, giving it a significant advantage in terms of safety.

[0005] To achieve the above-mentioned objectives, the present invention is implemented through the following technical solution:

[0006] A novel refrigerant that can replace R290 is a ternary mixture composed of hexafluoropropylene (R1216), propane (R290), and propylene (R1270); wherein the mass concentration of hexafluoropropylene (R1216) is 71-85%, the mass concentration of propane (R290) is 5-25%, and the mass concentration of propylene (R1270) is 1-20%.

[0007] Furthermore, the mass percentage concentration of hexafluoropropylene (R1216) is 74%–79%, the mass percentage concentration of propane (R290) is 12%–20%, and the mass percentage concentration of propylene (R1270) is 6%–12%.

[0008] Furthermore, its GWP value is less than 5, and its flammability is weaker than R290.

[0009] This invention discloses a novel refrigerant that can replace R290. Its preparation method involves physically mixing three component substances at room temperature according to their specified mass ratios. Each component in this invention is commercially available or can be prepared using methods known in the art. The basic parameters of each component are shown in Table 1.

[0010] Table 1 Basic physical parameters of each component

[0011]

[0012] The beneficial effects of this invention are:

[0013] (i) The novel refrigerant provided by this invention has an ODP value of zero and a GWP of less than 5. It has the characteristics of not damaging the ozone layer and having a small impact on the greenhouse effect, and has good environmental performance.

[0014] (ii) The novel refrigerant provided by the present invention contains a large proportion of the non-flammable working fluid R1216, which can suppress the flammability of R290 and R1270, improve the safety performance of the refrigeration heat pump system, and has obvious advantages in terms of safety.

[0015] (III) The novel refrigerant provided by this invention has a coefficient of performance (COP) and a cooling capacity per unit volume that are comparable to or even better than R290, and has high system cycle performance;

[0016] (iv) The novel refrigerant provided by this invention can be applied to R290 refrigeration, heat pump and low boiling point power cycle systems, without the need to replace many parts, only some parts need to be modified.

[0017] In summary, the invention can solve the safety problem of the flammability and explosiveness of the environmentally friendly refrigerant R290, and is of great significance for the promotion of R290 refrigerant in refrigeration, heat pump and low boiling point power cycle systems. Detailed Implementation

[0018] The present invention will be further described below through specific embodiments. These embodiments are provided to enable those skilled in the art to better understand the invention and are not intended to limit the scope of the invention.

[0019] In specific implementations of this invention, the refrigerants hexafluoropropylene (R1216), propane (R290), and propylene (R1270) used are all commonly used refrigerants in the fields of refrigeration heat pumps and low-boiling-point power cycle technology. They are physically mixed at different mass percentage concentrations in a liquid phase at room temperature and pressure, and after homogeneous mixing, a novel refrigerant capable of replacing R290 is formed. Several specific embodiments are given below, where the proportions of each component are mass ratios, and the sum of the mass ratios of the components in each mixed working fluid is 100%.

[0020] Example 1

[0021] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 74% / 25% / 1% in the liquid phase.

[0022] Example 2

[0023] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 75% / 5% / 20% in the liquid phase.

[0024] Example 3

[0025] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 71% / 12% / 17% in the liquid phase.

[0026] Example 4

[0027] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 85% / 7% / 8% in the liquid phase.

[0028] Example 5

[0029] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 74% / 20% / 6% in the liquid phase.

[0030] Example 6

[0031] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), at a mass percentage concentration of 79% / 12% / 9% in the liquid phase.

[0032] Example 7

[0033] A novel refrigerant that can replace R290 is obtained by physically mixing three components, hexafluoropropylene (R1216), propane (R290) and propylene (R1270), in the liquid phase at a mass percentage concentration of 74% / 14% / 12%.

[0034] The basic parameters, such as the environmental performance and temperature glide (at standard atmospheric pressure of 101.325 kPa) of the above embodiments and R290 working fluid, are recorded in Table 2.

[0035] The molar mass (g / mol), standard boiling point (°C), critical temperature (°C), and critical pressure (MPa) were obtained from REFPROP 10.0a, a working fluid property lookup tool developed by the National Institute of Standards and Technology (NIST).

[0036] The temperature glide (°C) was calculated using REFPROP 10.0a software via Matlab.

[0037] GWP data comes from the Intergovernmental Panel on Climate Change (IPCC) report, "Climate Change 2021: The Physical Science Basis".

[0038] Table 2 Comparison of basic physical properties of Examples 1-7 and R290

[0039]

[0040] As shown in Table 2, the GWP values ​​of the embodiments of the novel refrigerant that can replace R290 provided by the present invention are all less than 5, which has excellent environmental performance and meets the requirements of current international laws and regulations; the bubble point temperature of each embodiment is close to the standard boiling point of R290; the temperature glide of each embodiment is small, and each embodiment is close to an azeotropic refrigerant, which can reduce the adverse effects caused by the temperature glide of the working fluid during system operation.

[0041] Table 3 shows the comparison results of the thermodynamic parameters (discharge pressure and temperature) and relative system cycle performance (relative volumetric cooling capacity and relative COP of each embodiment relative to R290) of the above embodiments with R290 under the refrigeration conditions of evaporation temperature of 5℃, condensation temperature of 40℃, superheat of 10℃, subcooling of 5℃, and compressor overall efficiency of 0.8.

[0042] Table 3 Comparison of Cyclic Performance of Examples 1-7 and R290

[0043]

[0044] The evaporation pressure (MPa), condensation pressure (MPa), pressure ratio, exhaust temperature (°C), relative unit volume refrigeration capacity, and relative COP data are calculated based on a single-stage compression steam refrigeration cycle.

[0045] Table 3 shows that: 1. The volumetric cooling capacity of the new refrigerant in each embodiment is slightly higher than that of R290, and the system performance coefficient (COP) of the new refrigerant is very close to that of R290, indicating the feasibility of the new refrigerant as a substitute in terms of cycle performance; 2. The results also show that the evaporation pressure and condensation pressure of most embodiments are not much different from those of R290, and the pressure ratio of some new refrigerants is even smaller, which helps to improve the efficiency of the compressor; 3. As a substitute for R290, the discharge temperature of the new refrigerant system is comparable to that of the R290 system; 4. R1216 is a highly efficient flame retardant, so it can be predicted that the proportion of the mixture contained in the new refrigerant is mainly non-flammable or weakly flammable refrigerant, which increases the safety of system operation and working environment;

[0046] As can be seen, under the above operating conditions and within the preferred ratio range calculated theoretically, the system cycle performance of the novel working fluid of this invention, which can replace R290, is close to or even better than that of R290. Its outstanding advantage is that the new working fluid achieves a non-flammable or weakly flammable effect, exhibiting significant safety performance advantages compared to R290 refrigerant. In summary, the novel refrigerant described in this invention has excellent application effects and development potential when replacing R290.

[0047] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art, under the guidance of the present invention, can make many specific modifications without departing from the spirit and scope of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A refrigerant capable of replacing R290, characterized in that, The refrigerant is a ternary mixture composed of hexafluoropropylene (R1216), propane (R290) and propylene (R1270); wherein the mass concentration of hexafluoropropylene (R1216) is 71~85%, the mass concentration of propane (R290) is 5~25%, and the mass concentration of propylene (R1270) is 1~17%.

2. The refrigerant that can replace R290 according to claim 1, characterized in that, The mass concentration of hexafluoropropylene (R1216) is 74%~79%, the mass concentration of propane (R290) is 12%~20%, and the mass concentration of propylene (R1270) is 6%~12%.

3. A refrigerant that can replace R290 according to claim 1, characterized in that, Its GWP value is less than 5, and its flammability is weaker than R290.

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