Refrigerants
Refrigerants working fluid mechanical refrigeratwn systems. They transfer heat from the system to its environment. Refrigerant is a substance that absorbs the heat from other substances. The vapor-compression cycles, the refrigerant of the working fluid, which in turn evaporates and condenses as it absorbs releases and thermal energy. Is a suitable retrofit refrigerant must have certain chemical, physical and diermodynamic properties that make it a safe and economical in operation. There is no ideal refrigerant. Wide differences in operating conditions and requirements of the various applications make the ideal refrigerant impossible to achieve the goal. Therefore refrigerant approaches ideal conditions only under the condition that its properties that meet the conditions and requirements of a particular application.
The American Society of Heating, Refrigeration and Air-Conditioning Engineers, Inc. (ASHRAE) contains information about more than 100 refrigerants, their numerical designation, chemical formulas, ph diagrams, thermodynamic properties and other characteristics in their guide to the Basics.
ASHRAE HandbookRefrigeration also presents additional information describing the chemistry associated widi refrigerants. These comprehensive resources should be considered technicians and engineers to help themselves, to keep up with research that is done in the refrigerant industry. Research projects are constantly supports the refrigeration industry organizations to improve the refrigerants, equipment and technologies of development available for refrigeration, air conditioning and heat pumps.
Although many of the refrigerants currently discontinued due to their ozone depleting properties, they are still found in the equipment manufactured before their prohibition. The listing also contains some new refrigerant blends, which are already used, and others that are in various stages of development that shows promise as a future replacement.
Usually, security-related properties of the refrigerant one of the main issues in his choice for use in a specific application. For this reason, some liquids which are highly desirable properties as a refrigerant, are found only in limited use. Ammonia is one of the most famous liquids that fall into the category of being a good refrigerant, but with poor safety rating, which prohibits its use in many applications. Ammonia is highly toxic, presenting a serious danger if the system undergoes a leak in the pipeline. Right hydrocarbon refrigerants (methane, ethane, propane, ethene, butane and isobutane) are also classified as too risky to use in General refrigeration applications.
These refrigerants pose a significant risk of flamma-bility and burning associated widi their use. The following quality characteristics, which could allow a chemical or a chemical compound, to be suitable for use as a refrigerant.
- Promising refrigerant should be non-toxic in its pure form or in mixtures with air. It should not contaminate food or other products stored in the refrigerator place, if a leak develops in a dying system.
- Promising refrigerant should be nonflammable and use in its pure form or in mixtures with air.
- Promising refrigerant should not adversely react with lubricating oil in the system, or any material used in the construction of the equipment.
- Promising refrigerant should not adversely react with moisture that is present in varying degrees in all refrigeration systems.
- Promising refrigerant should be economically attractive and environmentally friendly, does not contribute to the destruction of the ozone layer or increase the earth's warming potential (greenhouse effect).
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Industrial