Heat recovery
Condensation of the refrigerant in the cooling system is warmer than the ambient temperature. The amount of heat rejected in the condenser cooling effect, and most of the compressor input power. Heat can be recovered:
- Reset vapor, which can be as hot as 150C. heat is removed in de overheating of the vessel between the compressor and condenser. The amount of heat available, however, a relatively small.
- Capacitor, which, as a rule, from 10 to 30C above ambient temperature.
- Used oil on oil cooled compressors, which can be between 60 and 80C.
It is important that the impact of heat on the productivity of the refrigeration system, carefully analysed. In many cases, the extraction of useful heat from the condenser, causes the system to run less efficiently (i.e. at higher temperature, the condensing), and savings in heating costs, as a rule, less than the added cooling costs.
De-superheater restores the high-temperature heat from the discharge of vapor coming out of the compressor. The temperature at the outlet depends on the operating conditions of the system and the refrigerant.
R22 and ammonia operate at much higher discharge temperature than most other refrigerants. In a well-developed system of cooling of the condensing temperature should be as low as possible. Any heat from the condenser will be at a very low temperature and very rarely useful.
In oil-flooded screw compressors much of the engine heat is dissipated in the lubricating oil. Oil, as a rule, enters the compressor about 40C and leaves it at 60-80C. For R22 systems, about 38% of the engine power would be absorbed by the oil and, therefore, be available for recovery. For ammonia systems, this figure increases to about 60%.
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Industrial