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The absorption refrigerator is a refrigerator that utilizes a heat source to provide the energy needed to drive the cooling system rather than being dependent on electricity to run a compressor. These refrigerators are popular where electricity is unreliable, costly, or unavailable. It has been suggested that this article or section be merged into refrigeration. ...
Lightning strikes during a night-time thunderstorm. ...
A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume. ...
In the developing world gas absorption refrigerators running on kerosene are very valuable where there is no reliable electricity supply. Besides the obvious advantages for food preservation, they supply safe storage of vaccines and drugs. Russian kerosene lamp Kerosene or paraffin oil (British English, not to be confused with the waxy solid also called paraffin) is a colorless flammable hydrocarbon liquid. ...
A bottle and a syringe containing the influenza vaccine. ...
Oral medication A medication is a licenced drug taken to cure or reduce symptoms of an illness or medical condition. ...
In the developed world, including the United States, absorption refrigerators are most often used for camping and in recreational vehicles, though some are used in remote areas or in off grid homes. The heat source that powers the refrigeration cycle is most often a propane burner, though other fuel gases such as butane and natural gas are sometimes used instead in areas where these are more readily available. Electricity can provide the heat for an absorption refrigerator and many camping versions can be switched to use it. In extremely remote areas, kerosene is used. Car camping with all the comforts Camping is an outdoor recreational activity involving the spending of one or more nights in a tent, primitive structure, a travel trailer or recreational vehicle at a campsite with the purpose of getting away from civilization and enjoying nature. ...
Recreational Vehicle (or RV) is a term used in North America to describe a large enclosed piece of equipment with wheels designed to be moved from place to place for people to temporarily live in and be protected from the elements while away from their permanent home. ...
The term off the grid refers to a method of construction that relies on renewable energy sources rather than traditional public utility sources provided by the utility grid. ...
Propane is a three-carbon alkane. ...
Butane, also called n-butane, is the unbranched alkane with four carbon atoms, CH3CH2CH2CH3. ...
Many stoves use natural gas. ...
Russian kerosene lamp Kerosene or paraffin oil (British English, not to be confused with the waxy solid also called paraffin) is a colorless flammable hydrocarbon liquid. ...
The cooling components of absorption refrigerators can be constructed without moving parts and with no reliance on electricity. However, most new units have thermostats, ignition systems, safety pilot controls, and lights that introduce some moving parts and reliance on a nominal amount of electricity -- little enough to be supplied by a dry cell or battery. A thermostat is a device for maintaining the temperature of a system within a range by controlling the flow of heat energy into or out of the system. ...
A pilot light is a small gas flame, usually natural gas or liquefied petroleum gas, which is kept alight in order to provide an ignition source for a more powerful gas burner. ...
// Dry cell schematic diagram A dry cell, also known as a Leclanché cell or a zinc-carbon battery, is a form of primary electrochemical cell that supplies electrical energy at small currents. ...
This article or section is missing references or citation of sources. ...
These refrigerators have the disadvantage of using a lethal gas, ammonia, although it is contained within a closed system; and if they are being run using an open flame then attention has to be paid to its safety and to maintaining the flame at an appropriate size. Ammonia is a compound of nitrogen and hydrogen with the formula NH3. ...
The basic principle of how these refrigerators cool their interior is the same as in conventional compression refrigerators. Both use refrigerant liquids that boil at low temperatures to achieve cooling. A large amount of energy is needed to turn the liquid into gas, and this is absorbed from the surroundings, cooling them. The difference is in how the gas is turned back to liquid to use it again for more cooling. A conventional electric refrigerator uses a pump to compress the gas back to liquid; a gas absorption refrigerator uses another liquid to absorb the gas and then has extra stages to separate the pure refrigerant liquid out again for re-use, this extra part being where the heat source is involved.
Variations exist, but the usual pattern of gas absorption refrigerator uses ammonia as the refrigerant and water as the absorber, with hydrogen gas included to adjust the pressure in the system. The exact mixture and pressure has to be correct to give proper cooling at normal temperatures. General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ...
The cooling system consists of four main parts: the evaporator, absorber, generator and condenser. The evaporator is where chilling happens as the liquid ammonia evaporates, absorbing heat from its surroundings to enable the liquid to turn to gas. The ammonia gas passes on to the absorber, where it dissolves in water. The solution flows down to the generator where the external heat source is used to bubble the ammonia out again. This gas is purified by condensing out water vapour before rising to the main condenser. The condenser has big fins on the outside which let air cool it sufficiently for the ammonia to flow out of the bottom as a liquid again, down into the evaporator. Water (from the Old English waeter; c. ...
The hydrogen plays an interesting part in making this cycle work. Why does the ammonia which turned to liquid in the condenser then evaporate at essentially the same temperature and pressure in the evaporator? Because the evaporator also contains hydrogen gas, and the partial pressures exerted by the two gases mean that the ammonia liquid will evaporate (Dalton's law applies). The hydrogen is present in the absorber too, but is not absorbed as it does not dissolve in the water. In chemistry and physics, Daltons law (also called Daltons law of partial pressure) is related to the ideal gas laws. ...
The ammonia, water and hydrogen system is closed. The water in the absorber is actually a weak solution of ammonia carried out of the generator when the ammonia bubbles out by a "bubble pump" like the pipe of a coffee percolator. There is no other pump in the system, liquids flowing back down under gravity and the gas pressure being the same throughout the system.
There are other gas absorption refrigerators which use only ammonia and water with a heat source applied intermittently, possibly just once a day. These have a pressure valve between the condenser and evaporator so that the generator and condenser are pressurised when the generator is heated. The liquid ammonia is forced slowly through the valve from the high pressure side into the evaporator where it evaporates in the lower pressure. The pressure differential will last for some time after the heat source is removed, so active cooling occurs for longer than the time the heat is applied. When the pressures have equalised, the ammonia solution from the absorber can flow back into the generator ready for the cycle to start again.
Gas absorption cooling principles can be applied at other temperatures, notably for air-conditioning where water may be the refrigerant, evaporated at low pressure and absorbed into a salt solution. A magnified crystal of a salt (halite/sodium chloride) In chemistry, a salt is any ionic compound composed of positively charged cations and negatively charged anions so that the product is neutral and without a net charge. ...
History
The absorption refrigerator was invented by Baltzar von Platen and Carl Munters in 1922, while they were still students at the Royal Institute of Technology in Stockholm, Sweden. Commercial production began in 1923 by the newly formed company AB Arctic, which was bought by Electrolux in 1925. Baltzar von Platen ( 1898- 1984) together with Carl Munters was the inventor of the gas absorption refrigerator in 1922 while they were both Swedish engineering students at the Royal Institute of Technology in Stockholm, Sweden. ...
1922 (MCMXXII) was a common year starting on Sunday (see link for calendar). ...
The Royal Institute of Technology or Kungliga tekniska högskolan (KTH) is a university in Stockholm, Sweden. ...
Stockholm panorama from the City Hall is the capital of Sweden, located on the south east coast of Sweden. ...
1923 (MCMXXIII) was a common year starting on Monday (link will take you to calendar). ...
Electrolux is a Swedish company that is the worlds largest manufacturer of kitchen, cleaning and outdoor appliances for both home and professional use. ...
1925 (MCMXXV) was a common year starting on Thursday (link will take you to calendar). ...
Bibliography In Swedish: - Baltzar von Platen and Carl Munters, Om alstring av kyla (1925)
There are few good explanations on the web of how gas absorption refrigerators work, and some very bad ones. A useful reference is: There is another explanation here with a helpful diagram -- both possibly originated from Elecrolux: This goes into great detail: - Ohio State University Center of Excellence in Absorption Technology: Theory of Heat Pump Operation
This is a home-made absorptive refrigerator: - Some home made icyballs including instructions and diagrams
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