The Numerical Study Of Ammonia Absorption Combined Refrigeration Cycle For Indirect Air-cooling System

Aiming at the defects of the existing air-cooling technology, particularly thedefects of compressor has huge investment and consumption large power in thecompression combined refrigeration cycle power plant indirect air-cooling system(thefollowing referred to as composite indirect air-cooling system), a new air-coolingsystem by steam power cycle coupled with the positive and negative sequencerefrigerating cycle was presented, is a ammonia absorption composite indirectair-cooling system). The technology both keeps the existing high water rates of directcooling techniques and reduces energy consumption, and achieves full-year full-fat,no damage, water vapor zero emission.This paper introduced the working principle and working process of ammoniaabsorption composite indirect air-cooling system, and pointed out the innovationpoints of the new system: proposed to replace the compressor by ammonia absorptionrefrigeration cycle as a work loop of heat periods in composite indirect air-coolingsystem, designed air-cooled plate-fin-type absorber to replace the water consumption,designed air-cooled plate-fin-type absorber to replace the water consumption andcompact degree is small for the traditional water-cooled and vertical falling filmabsorber. Then we analyze and forecast the economic benefits and energy savingeffects these innovations may bring about. Based on the analysis and comparison ofexisting numerous refrigerants working fluid properties and application status, wereached the conclusion after a detailed demonstration: Ammonia is the most suitablerefrigerant medium, and it is safety reliable, eco-friendly, and cost-effective, so it isthe best choice.Aiming at the urgent need for the development key equipment of compositeindirect air-cooling system, detailed design calculations the thermal parameters andthe corresponding geometry parameters of design conditions about the phase change heat transfer devices, plate-fin ammonia air-cooled radiator and absorber and otherlarge equipments in ammonia absorption composite indirect air-cooling system.Considering there are significant differences in running and design conditions ofthe composite indirect air-cooled system when environmental parameter changes inruntime. The characteristics under variable conditions of composite indirectair-cooled system need to be calculated and analyzed, obtaining the law of facingwind velocity, ambient-temperature, and flow rate variation of exhausted steam fromthe unit affecting the back pressure, providing with basis for determining reasonableoperation mode and control pattern of composite indirect air-cooled unit underoff-design conditions. Established economic evaluation models of this system, andmake a calculation example, the energy saving of new system meets the designexpectations.