CO2/R170 azeotropic refrigerant

Abstract

The invention relates to an azeotropic refrigerant, in particular to an azeotropic refrigerant capable of replacing R134a. The refrigerant can be applied to a single-stage or double-stage refrigerating / heating system, the azeotropic refrigerant consists of CO2 AND r170, when the mass ratio of CO2 is 78-80.6%, temperature glide is 0 DEG C, a temperature range corresponding to a bubble point temperature is [minus 6 DEG C-18 DEG C], the azeotropic refrigerant is used for replacing R134a, has low GWP value and low flammability, a temperature glide value is zero, a COPheat value is high, theoretical specific power is low, discharge temperature is low, compression ratio is low, similar heating ability is achieved, efficiency is high, and the zeotropic refrigerant capable of replacing R134a is suitable for being used in a relatively cold region.

Description

technical field [0001] The invention relates to a refrigerant, in particular to an azeotropic refrigerant which can replace R134a, and the refrigerant can be applied to a single-stage or double-stage refrigeration / heating system. Background technique [0002] R134a is widely used as air-conditioning refrigerant and heat pump system refrigerant due to its excellent performance, but because of its greenhouse effect as high as 1430, it is listed as one of the high-GWP value refrigerants eliminated by the "Kyoto Protocol". Any substance that wants to replace an existing refrigerant must have a performance parameter COP similar to that of the original refrigerant. In addition, the ozone depletion potential ODP and the greenhouse effect potential GWP must be within the allowed range. The pure substance replacement refrigerants developed so far are all different from the original refrigerants in volume and capacity, so it is difficult to make a performance parameter COP similar to ...

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Problems solved by technology

Niu Baolian et al. in "CO 2 / R170 mixture as a cascade refrigeration system low-temperature cycle refrigerant performance "in the article, the ratio of 50% / 50% CO 2 / R170, as a refrigerant in a cascade refrigeration system, has an evaporation temperature range of -65°C to -80°C. However, the mixed refrigerant in this temperature range and ratio can only be used as a non-azeotropic refrigerant. In a cascade refrigeration system, it cannot be applied to a single-stage compression cycle or a two-stage compression cycle

At the same time, if there is leakage or refilling of the refrigerant during application, the composition of the zeotropic refrigerant will change. In order to ensure that the composition does not change, it is generally necessary to empty all the remaining refrigerant and recharge it, resulting in a huge loss. waste

[0005] Similarly, during the operation of the system, the near-azeotropic refrigerant still has the problem of component migration because its temperature glide still does not reach 0°C. The component migration of the circulating working fluid will directly change the operating parameters of the system. The greater the degree of migration, the greater the change in system performance. In severe cases, it may lead to imbalance of refrigerant flow control and the system cannot operate safely.

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