For more than a century, refrigerants have undergone a continuous development process. In 1805, Oliver Evans was the first
The idea of using volatile fluids to freeze water into ice in a closed cycle is proposed. In 1824, Richard Tre sang
Vithick first proposed the idea of an air refrigeration cycle, but did not build this device. Living in the United States in London in 1834
Jacob Perkins successfully developed a vapor compression refrigeration device using volatile liquid ether (R610) as the refrigerant.
Set up and obtained a British patent (No. 6,662). His assistant John Haig modified the equipment and tried to change it.
Change to a special refrigerant-raw rubber, which is a volatile solution obtained from the decomposition and distillation of natural rubber.
In 1844, American Dr. John Gorrrie built an empty space in order to alleviate the pain caused to patients by the hot and humid summer weather.
The gas cycle refrigerator is used to make ice cubes.
The idea of using carbon dioxide to realize a vapor compression refrigeration cycle was first sung by Alexan of Newport, Connecticut, USA
der Catlin T wining proposed in 1850. However, the first successful commercial application of carbon dioxide was two
Carbon oxide gas military balloon expert, T haddeus Sobeski Carlincourt Lowe of New Hampshire. 1866
Around the year, he used carbon dioxide refrigeration mechanisms in places such as Dallas, Texas and Jackson, Mississippi.
For commercial ice, a carbon dioxide ice maker is also installed on the ship to transport frozen meat in the Gulf of Mexico. In 1867,
He obtained a British national patent for a carbon dioxide ice maker. Although carbon dioxide has been used to a certain extent, it is directly
By 1886, after Franz Windhausen of Bruswick, Germany successfully designed a special carbon dioxide compressor,
The carbon dioxide refrigeration working fluid has been significantly developed. According to statistics, there were 356 ships in the world in 1990.
Among them, 38% use air compression cycle refrigerators, 37% use ammonia absorption refrigerators, and 25% use carbon dioxide vapor compression refrigerators.
Refrigerator. Developed to 1930, 80% of the world’s ships used carbon dioxide refrigerators, and the remaining 20% used ammonia.
Refrigerator. Later, due to the rise of CFCs (hydrochlorofluorocarbons), the production of carbon dioxide refrigerators began to shrink.
Reduced, the last CO2 refrigeration ship ceased service around 1950.
Author of this chapter: Yang Zhao, Tianjin University.
Ammonia refrigerant was first used in the refrigeration equipment of a brewery in New Orleans, USA in 1869. The designer was two
French . Initially, there was no source of ammonia, only ammonia water was used, and water easily caused damage to the refrigeration system, so the early
The refrigeration equipment has to adopt some temporary emergency measures, such as using quicklime and sodium hydroxide to dry the ammonia.
Management. The ammonia refrigerant used directly in refrigeration equipment was introduced by McMillan of Cleveland in 1876. Soon after,
Many manufacturers are racing to produce anhydrous ammonia. Ammonia refrigerant reached the peak of its application around 1900, and its market day
Shrinking gradually. Ammonia refrigerant is a high-pressure refrigerant and is not suitable for working in tropical areas, while ether is a low-pressure refrigerant.
The equipment easily penetrates into the air and causes the system to fail. To overcome the above-mentioned shortcomings, the Swede Lau Picket
In 1875, a new type of refrigerant, sulfur dioxide, was developed, which has a moderate working pressure and is suitable for tropical environments.
It can prevent air from penetrating into the system, and at the same time, it is low in cost. It seems to be an ideal refrigerant. However, later practice
It proves that sulfur dioxide is only suitable for small-scale systems. In large-scale equipment, the refrigeration efficiency is low, and the ammonia trace control is more difficult.
Difficult, not suitable for small-scale systems, but refrigeration in large-scale equipment is none other than that. Therefore, sulfur dioxide has never been
Completely replace the position of ammonia.
Almost at the same time as sulphur dioxide, there is also a well-known refrigerant — methyl chloride, also known as methyl chloride
Alkane. The serious consequences it caused have caused huge losses to the reputation of the refrigeration industry. It was originally used as a surgical amputation
Anesthetics were used in the French battlefields. They were used as refrigerants by the French after 1878. They were mainly popular in Europe. Since 1910,
It was later accepted by American companies. Due to the lack of sufficient understanding of its physical chemistry and thermodynamic properties, until
It was only allowed to enter the commercial market in 1918, and was widely used in household and small refrigeration equipment after 1922.
In the first few decades, people used natural refrigerants. In contrast, ammonia and carbon dioxide are ideal.
However, the working pressure is very high, and ammonia is toxic and combustible under certain conditions. As for sulfur dioxide, it is more toxic than ammonia.
Sex. Due to the lack of ideal refrigerants, the development of artificial refrigeration was greatly restricted in the early 20th century.
At the beginning of the 20th century, two other working fluids were used. They were dichloroethylene (R1130) and isobutane.
(R600a), of which dichloroethylene is used in centrifugal compressors by Willis Carrier. Although these refrigerants exist
Many shortcomings and shortcomings, but provide more options. In practical applications, because ammonia and sulfur dioxide are toxic
Ether is explosive, and ether is explosive. Therefore, before 1932, people thought that methyl chloride and ethylene dichloride were the most ideal combination.
A promising refrigerant. At that time, most scholars believed that very few refrigerants could replace them. So he
Our main focus is on preventing leakage, because the leakage of these gases will directly endanger people's health.
Due to the poor safety of most natural working fluids, Friguer, the largest manufacturer of household refrigerators in the United States at the time,
Assertion: If you want to get out of the predicament, you must have a brand-new refrigerant, the standards are: non-toxic, non-flammable, non-explosive,
Does not corrode, does not reduce the effect of lubricating oil, has low boiling point and solidification temperature, and moderate industrial pressure. The company requires general motors to implement
The laboratory developed this ideal refrigerant, based on the research team headed by Thomas Midgley (Thomas Midgley).
This book has achieved the above goals, and this result is chlorofluorocarbons (CFC), also known as "freons". 1928 Thomas M
Jerry and Albert Henne searched for a compound with a suitable boiling point from the physical property table at that time.
The conditions are good stability, non-toxic and non-combustible. Fluorine itself is toxic, but fluorine-containing compounds can be non-toxic. when
Realizing that the boiling point data of carbon tetrafluoride published at that time was wrong, they turned to study the periodic table of
Undesirable volatile elements are deleted from the periodic table, and then elements that cause unstable and toxic compounds are deleted
And low-boiling inert gas elements. In the end, only 8 elements remain, namely C, N, O, S, H, F, Cl and Br.
After combining the “rows” and “columns” of the periodic table, they found that the element F is located in the “rows” and “columns” of the eight elements.
At the intersection of the "columns", three interesting observations were made and discovered:
(1) From left to right, the flammability of these elements decreases.
(2) From the heavy element at the bottom to the light element at the top, the toxicity decreases.
(3) The well-known refrigerant at that time was nothing more than a combination of 7 elements other than F, except that it did not contain F elements.
vegetarian .
So the goal of element F is determined. They fluorinated or chlorinated hydrocarbons and explained that the compounds become
How will the points affect the flammability and toxicity. In 1931, fluorine-containing compounds realized industrial production, thus uncovering the organic
The first page of the fluorochemical industry. Teflon was discovered in the United States in 1938. In World War II, the United States
In order to develop the atomic bomb, it is necessary to separate the uranium 235 by the gas diffusion method. Uranium hexafluoride is very corrosive, and the materials used in the production equipment
· 2 · Research and Development Report on the Progress of Refrigeration Discipline
Corrosion-resistant materials are required for quality, sealing and grease, and the polymer properties of organic fluorine compounds are suitable for this purpose.
This has promoted the in-depth research and practical application of fluoropolymers. The fluoropolymers available at that time were: fluoromethyl
Alkane (R41), chlorofluoromethane (R31), dichlorofluoromethane (R21), trichlorofluoromethane (R11), difluoromethane
(R32), difluorochloromethane (R22) and difluorodichloromethane (R12). These chlorofluorocarbon refrigerants are non-toxic and non-toxic
Odor, non-flammable, stable chemical properties, and low price. In the U.S., the situation at that time was: Used as a refrigerant
Accounted for 35. 3%, foaming agent accounted for 34.6%, solvent accounted for 18.1%, disinfectant accounted for 5.4%, other uses accounted for 6.6%.