INFLUENCE NON-CONDENSABLE GASES ON THE WORK OF A LARGE CAPACITY AMMONIA REFRIGERATING UNIT

Abstract

The efficiency of an ammonia refrigeration unit (ARU) depends on many factors. Changes of some of them result in thermal-hydraulic oscillations arising within the system. They are caused by changes in ambient temperature, the performance of the compressor and condenser. All this leads to the pressure increase in the condenser and, consequently, to the excessive energy consumption, which is perceived as the presence of non-condensable gases (NCG) in the system. This brings about more frequent opening of NCG relief valves, resulting in a substantial loss of ammonia. To eliminate these fluctuations frequency and duration of opening/closing the NCG relief valves on the torch from high pressure receivers are developed. New algorithms and modes of operation of the NCG discharge valves on the torch which allow reducing the frequency of oscillation phenomena and the loss of ammonia by 10 times are developed and validated.