Can you imagine a modern house without a refrigerator? Well, it’s hard to even think what we’d do without refrigeration. Modern cities in developed countries rely heavily on refrigeration to keep perishable foods fresh and safe for daily consumption. The refrigeration technique has impacted agriculture, industry and lifestyles over the centuries, evolving from ice harvesting to temperature controlled train carriages.
Refrigeration is the name given to the process that ‘removes heat from one place to another’ creating a cool or cold environment that has many applications such as domestic refrigerators, air conditioning systems, cryogenic facilities and industrial freezers.
The idea of cooling drinks has its origins in the ancient Chinese and Roman empires. The seasonal harvesting of snow and ice is a practice that predates 1000 BC. C. according to a collection of Chinese letters from the period known as the Shih dynasty. The next mention of ice harvesting is from the time of the Jews and is mentioned in the book of Proverbs of the Bible. Other civilizations, such as the Egyptians, Greeks, and Romans, made use of large snow pits lined with tree branches and straw to cool drinks and keep fruit cool. But it is not until the Persian culture when the use of an ice well called Yakhchal is mentioned; this may be the precursor to cold storage of food for preservation.
In the early 1800s, ice became a mass market product with the vast majority of people using ice chests to store dairy products, fish, fruit, meat and vegetables, thus paving the way for the acceptance of the technology. of refrigeration.
Refrigeration – the timeline
William Cullen, a Scottish professor, was the first to examine the idea of artificial refrigeration by creating a partial vacuum over a container of diethyl ether that absorbed heat from the surrounding air. This was in 1755, but the experiment had no practical application at the time.
In 1758, Professors Benjamin Franklin and John Hadley investigated the principle of evaporation as a means of rapidly cooling an object by conducting an experiment at Cambridge University.
In the year 1820, the renowned British scientist Michael Faraday used high pressures and low temperatures to liquefy ammonia and other gases.
American scientist Jacob Perkins, working in Britain in 1834, assembled the first closed-loop vapor compression refrigeration system. Although the non-patented prototype was the first known system to work successfully, it was not commercially successful.
The American physician John Gorrie made a similar attempt in 1842, but it was again a commercial failure.
The first practical and patented vapor compression refrigeration system using alcohol, ether, or ammonia occurred in 1856 and was built by James Harrison.
In 1860, Ferdinand Carre of France patented his gas absorption refrigeration system design called “aquatic ammonia”, the process of using gaseous ammonia dissolved in water.
Meanwhile, an engineering professor at the Munich University of Technology in Germany had been working on an improved method for liquefying gases. In 1876 he patented this new process which was made possible by the use of gases such as ammonia, sulfur dioxide and methyl chloride as ‘refrigerants’, a practice which became widely used until the late 1920s.
A refrigerant is a substance or chemical that is used in a thermal cycle, such as refrigeration, to convert a liquid into a gas.
In the early 19th century, refrigeration came to play a vital role in the food distribution industry, first through natural ice and then through manufactured ice. Many food and meat packers in the United States have adopted ammonia cycle refrigeration units for their storage facilities.
With the idea of artificial refrigeration being a great success, the idea of refrigeration for domestic purposes arose. The limitations were largely due to size, as they were designed for installation on trucks, trucks, and warehouses, and the safety factor in case of fire accidents where toxic gases leaked or exploded.
home refrigeration
In 1911, General Electric (GE) became the first company to overcome the challenges of meeting the cooling needs of the home. GE launched a gas-powered home unit that eliminated the need for an engine and greatly reduced the size of the unit. However, the idea of a gas-fired unit was not well received by GE’s electric customers, so an electric model frame was put into operation.
In 1927, the Monitor Top, the world’s first electrically powered refrigerator, was launched. The idea created waves with many other companies jumping on the bandwagon in the lead up to improving on this new invention.
One of GE’s main competitors, Frigidaire entered the fray in 1930, synthesizing freon as a refrigerant. This was a revolutionary invention that allowed the development of cheaper, lighter and smaller refrigerators for home use. At the time, the use of chlorofluorocarbons (CFCs) was considered less harmful than commonly used refrigerants such as ammonia, methyl chloride, and sulfur dioxide. The intent was to provide safer home computers at affordable prices.
Today, home refrigerators have become stylish appliances with a variety of designs, colors and sizes with different temperature control functions to meet the needs of small, medium and large families.
environmental concerns
In the 1970s, as the world became aware of environmental concerns and global warming, these CFC compounds were found to react with the protective ozone layer of the atmosphere, reducing the use of CFCs as a refrigerant, as reported. set out in the 1987 Montreal Protocol. Today, manufacturers have embraced the idea of using green refrigerants such as hydrocarbons as a means of combating global warming and reducing the impact of greenhouse gases.
