Large Power Station Air Cooling Unit Vacuum Deaerator Thermal Performance Research

As known to all, north-west of our country where contain rich coal resource isextremely lack of water. Thus using air cooling system instead of water cooling systemprevails in power plants in this area. However, large amount dissolved oxygen in thecondensate of air cooling unit will do great damage to the steel made equipments suchas feed pipe, boiler, and heat exchanger etc. It is necessary to have the feed waterdeaerated to ensure the safety of these thermal equipments.Deaerating process in air cooling system performs under vacuum conditionwhich is different than that under positive pressure. In this article, it analyzed thedifferent factors at length which influenced the efficiency of deaerating undervacuum condition according to the principle of thermal deaerating.A structure of spray-tray deaerator was proposed in this article to conduct a prooftest of vacuum deaerating. A vacuum deaerating system was then established under theabsolute pressure of15kPa and large amount of data had been collected during the test.Based on these data such as temperature, flow rate, heating capacity and oxygen content,it was possible to analyze the capacity of deaerating under different conditions. In theend, presumption and rules were summarized from this testing and the results wouldhelp us to design a more effective deaerator for air cool unit in the future.