RESEARCH OF REFRIGERATINGS R22, R410A, R290 AND R32 UNDER THE SAME CONDITIONS

ABSTRACT

The article explores the ozone layer, the cooling agents that cause it to degrade, and the alternatives to these cooling agents. The study was presented under the same conditions, in the cooling mode, in binding to environmentally friendly refrigerants. Comparisons were made between refrigerants R22, R410A, 290 and R32 used in a split air conditioner with a capacity of 12,000 Btu / s.

АННОТАЦИЯ

В статье исследуется озоновый слой, охлаждающие агенты, вызывающие его разложение, и альтернативы этим охлаждающим агентам. Исследование проводилось в тех же условиях, в режиме охлаждения, с привязкой к экологически чистым хладагентам. Были проведены сравнения между хладагентами R22, R410A, 290 и R32, используемыми в сплит-кондиционерах с производительностью 12 000 БТЕ / с.

Keywords: R22, R410A, 290, R32, split conditioner, cooling agent, alternative, Ozone, XFU, GXFU.

Ключевые слова: R22, R410A, 290, R32, сплит-кондиционер, охлаждающий агент, альтернатива, озон, XFU, GXFU.

Introduction

It is impossible to imagine our lives and activities today without artificial cold. Life on earth has been preserved for thousands of years because of its protective atmosphere. This layer is made up of ozone, which protects the earth from the sun's harmful ultraviolet rays. We know that this is a wonderful feature of our planet. If the protective layer is broken, the sun's ultraviolet rays can affect the earth's surface and kill most living organisms.

Ozone is an oxygen molecule made up of three atoms instead of the usual two. The extra atom causes the oxygen in the air to be such that even small doses that can be ingested by humans can be toxic and fatal. Ozone molecules are formed and decomposed by natural atmospheric processes. The sun's ultraviolet rays break down oxygen molecules into atoms. In this way, these atoms combine with other oxygen molecules to form ozone.

Ozone is not a stable gas and is sensitive to natural components such as nitrogen, hydrogen and chlorine, which can cause it to decompose. Ozone is a photochemical process on the Earth's surface (stratosphere) and represents a pollutant that causes alkaline precipitation. But at a safe altitude of the stratosphere, from 10 km to 50 km, this blue pungent-smelling gas is just as important to human life as oxygen.

The global consensus is that the release of artificial chemicals containing chlorine into the atmosphere causes the ozone layer in the stratosphere to be depleted. Most of these substances are chlorofluorocarbons (HFUs) and gallons (used in fire extinguishers), which have a good ability to deplete the ozone layer. XFU has been used for many years as a cooling agent in refrigeration machines, solvents, and foaming agents.

The beneficial use of these immutable chemicals on Earth is causing the ozone layer to deplete. The substance reaches the stratosphere unchanged and splits under the influence of intense UV-C ultraviolet light. The sun's ultraviolet rays break down oxygen molecules into atoms, which then combine with other oxygen molecules to form ozone. Chlorine removes one atom from the chlorine-ozone molecule released by radiation from the storage molecules and forms chlorine oxide (ClO) and simple oxygen. As a result of the reaction with oxygen, chlorine is released again, forming a new simple oxygen molecule. Thus, chlorine acts as a catalyst with the ability to decompose, and the process continues as long as there is no change in the chlorine molecule. Each molecule of chlorine causes thousands of molecules of ozone to be disturbed and the balance of nature to be disturbed.

Long-lasting chemicals are the most dangerous. The average lifespan of XFU-11 is 50 years, XFU-12 averages 102 years, and XFU-113 averages 85 years. Therefore, even after these substances are discontinued, the depletion of the ozone layer by these substances will continue for several years.

Chlorofluorocarbons are now cited as the main cause of ozone depletion. Every spring, an ozone-sized "hole" the size of the United States is formed over Antarctica in the south of the globe. When we say "hole", it is not a hole, but the concentration of ozone in that zone decreases.

In the 1980s, chlorofluorocarbons (XFUs) and hydrochlorofluorocarbons (GXFUs) proved to have an effect on the ozone layer, which protects the earth’s flora and fauna from the sun’s harmful ultraviolet rays. According to the 1985 Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol on the Control of Ozone Depleters, the use of XFUs is limited to 1996 for developed countries and until 2010 for developing countries. The use of it was allowed until 2020 for developed countries and until 2030 for developing countries.

For this reason, our country has also stopped using the refrigerant R22, which is harmful to the ozone layer, and is switching to a refrigerant that does not pose a threat to the ozone layer. The ozone depletion potential (ODP) of the refrigerant R22 is 0.05. The boiling point is - 40.85, the critical temperature is 96.13, and the working pressure is between 3.15.7 bar.

Currently, R410A and its alternative R32 refrigerant are being used as an alternative to R22 refrigerant. The most advantage of these R410A and R32 refrigerants is that the ozone depletion potential is 0. For this reason, this refrigerant is used in practice. Let's take a look at the laboratory results of these refrigerants.

Research methodology and results

The following diagrams show the parameters of the four refrigerants discussed above under the same conditions study. The study was conducted at a boiling point = 8.9 and a condensation temperature = 50.6. This is the cooling mode.

Figure 1. Interrelationships of refrigeration performance of refrigerants R22, R410A, R290 and R32

The study showed that under the same conditions, the cooling efficiency was much higher at R32 (Figure 1). 1.2 times higher than R410A, 1.5 times higher than R22, and almost twice as low as R290, which had the lowest score, 1.97 times positive.

Figure 2. Electrical power ratios of refrigerants R22, R410A, R290 and R32

This diagram (Figure 2) shows the results for the power consumed. R32 also showed the highest result on this indicator, but it was a negative result, and the most positive result was a positive result compared to R32 with almost twice as much cooling agent R22, i.e. 1.96 times less. showed. The R290 also showed a positive result close to R22. R410A has a negative result with R32.

Figure 3. Reciprocity of cooling coefficients of refrigerants R22, R410A, R290 and R32

As mentioned above, if we look at the essence of the cooling coefficient, the cooling coefficient is equal to the ratio of cooling efficiency to electricity. That is, the relationship between cooling efficiency and electricity. If we look at this diagram (Figure 3) as a summary, the R22 refrigerant turns out to be the best, positive refrigerant. But we must not forget that R22 is not an environmentally friendly cooling agent.

Conclusion.

According to the results of the study of refrigerants R22, R410A, R290 and R32 under the same conditions:

• Under the same conditions, the refrigeration efficiency of R32 refrigerant was 1.2 times that of R410A, 1.5 times that of R22, and almost twice that of R290, i.e., 1.97 times the positive result;
• In terms of power consumption, R32 showed the highest negative result, while the most positive result was R22 cooling agent with 1.96 times less than R32. The R290 also showed a positive result close to R22. R410A has a negative result with R32;
• In terms of cooling coefficient, refrigerant R22 turned out to be the best, positive refrigerant.

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