Want to refrigerate more environmental protection "non-fluorine refrigerant" you know how much

What is "Fluorine-Free Air Conditioning"? A consumer who is purchasing air conditioners said, “I only heard of non-fluorine-free refrigerators, and non-fluorinated air conditioners may be the same reason, there is no Freon!” Obviously, the concept of “non-fluorinated air conditioners” is not so deeply rooted, but People vaguely know that there is a substance called “Freon” in the refrigerants of traditional refrigerators. This kind of substances will destroy the ozone layer of the atmosphere and people will be included in the “black list” that is not environmentally friendly. Then, what does "non-fluorine" refer to, which is the traditional refrigerant "R22", Freon, or "fluorine"?

"Fluorine-free" is actually free of "chlorine" elements

At present, the commonly used refrigerants in the air-conditioning industry are R410A, R22 and R134a. The vast majority of “fluorinated air conditioners” on the market use R22 refrigerants containing “chlorine” elements, and the industry is accustomed to using the new refrigerant R410A as “non-fluorinated air conditioners”. According to professional analysis, environmental protection of refrigerants is not environmentally friendly and “fluorine” and “freon” are irrelevant, but related to “chlorine”. The destruction of the ozone layer is mainly due to the chlorine atoms contained in refrigerants, foaming agents, fire extinguishing agents, and cleaning agents that are widely used, and they diffuse into the upper atmosphere. Ozone in the stratosphere is catalyzed by chlorine, resulting in thinning of the ozone layer. disappear. In installation and maintenance, "R410a" refrigerant does not contain "chlorine" elements, will not damage the atmospheric ozone layer, and will not cause human health due to Freon leakage. Therefore, many manufacturers call it "F410a free of fluorine Refrigerant."

Discard halogen elements, hydrocarbons, and refrigerants

According to the provisions of the Montreal Protocol, the global use of R22 will be fully restricted by 2030. The synthetic refrigerant R410A, which is currently the most popular transitional alternative working fluid, still contains fluorine. It is not "fluorine-free" in the true sense. However, although it has zero damage to the ozone layer, it produces greenhouse gas effects. It even partially surpassed R22. Therefore, R410a is not the ultimate environmental refrigerant solution for China's air-conditioning industry.

Compared with the above two products, hydrocarbon refrigerants do not damage the ozone layer, have no greenhouse effect, and are completely environmentally friendly. The R290, which is currently being promoted as propane, is a good choice.

Refrigerant R290, propane, is a natural hydrocarbon refrigerant that can be obtained directly from liquefied gas. Compared with Freon, which is a synthetic refrigerant, the natural working fluid R290 contains no chlorine atoms in its molecules, so the ODP value is zero and it has no destructive effect on the ozone layer. In addition, compared to HFC materials that are also non-destructive to the ozone layer, the GWP of R290 is close to zero, and has no effect on the greenhouse effect. Currently in Germany R290 has been used in domestic water heaters and air conditioning systems.

In the saturated liquid state, the density of R290 is smaller than that of R22. Therefore, the perfusion volume of R290 is smaller under the same volume. The experiment shows that the perfusion volume of R290 is about 43% of R22 under the same system volume. In addition, since the latent heat of vaporization of R290 is approximately twice that of R22, the refrigeration cycle of the R290 refrigeration system is smaller. R290 has good material compatibility and is well compatible with copper, steel, cast iron, and lubricants.

Although R290 has the above advantages, its disadvantage of being "flammable and explosive" is the biggest obstacle that currently restricts its large-scale promotion. Mixing R290 with air can form an explosive mixture, which can cause a burning and explosion hazard when exposed to heat and open flames. Measures to improve the safety of the R290 include reducing the amount of filling, insulating the ignition source, preventing leakage of the refrigerant, and improving the safety prevention and control capabilities after the leakage.

In order to reduce potential safety hazards, the IEC standard limits the maximum safe filling volume of R290 refrigerant: when installed at a height of 2.2 m in a 10 m2 room, the filling volume must be less than 290 g. Reducing the filling volume can reduce the amount of refrigerant leakage to a certain extent, thereby improving the safety of the R290. Does reducing the refrigerant charge result in a decrease in cooling capacity? In this regard, the industry sources said that the R290's latent heat of vaporization is about twice that of R22, which means that the unit mass R290 has a higher cooling capacity. And at present, the experiment has confirmed that in the case of reducing the amount of R290 refrigerant filling, the cooling effect of R22 can be completely achieved or exceeded through the structural transformation of the refrigeration system.

Reducing leaks and improving leakage detection and response capabilities are important measures to improve the safety of R290. It is understood that most manufacturers currently have high requirements for the air-conditioning seal testing standards, and the normal air-conditioning leakage can be controlled below 5g, without any danger. The refrigerant leakage that appears now is mainly concentrated in the process of air-conditioning installation, use, and maintenance. In these processes, there are many uncontrollable factors such as the environment and the mode of use. Therefore, the safety control measures in these processes still need further study and improvement.

Another air-conditioning refrigeration market experts said that by improving the detection of refrigerant leakage, as well as leakage of response speed and ability, will greatly reduce the risk of R290. If a refrigerant leakage concentration detection device is added to the air-conditioning system, once the leakage concentration exceeds a preset value, preventive measures such as power-off, ventilation, and alarms are automatically performed to avoid potential safety hazards. Therefore, by improving stringent control and prevention measures, R290's “flammable and explosive” hazards can be effectively controlled. At present, it is still the most promising alternative to HCFC.