Cooling of waste steam from thermal power generation and cogeneration, mainly used in water-deficient areas.

　　This cooling system takes air as the cooling medium. Exhaust steam from the turbine is directly cooled and condensed into water through the air-cooled condenser.

　　Its main feature is saving water, however, the back pressure of the turbine will be greatly impacted in the summer or when there is heavy wind. It is suitable for water-deficient areas with low ambient temperature and a large amount of coal.

　　1. Components of direct air cooling system:

　　Air cooling condensation system: air cooling tube bundle, steam distributing pipe, upper and lower tube bundle connection box and an A-shaped rack

　　Air supply system: draught fan, electrical machine, reduction box, fairing and protecting net

　　Exhaust duct system: pipeline between outlet of exhaust unit and steam distributing pipe, and expansion joint, isolating valve, safety valve, rupture disk and water drainage pipeline

　　Condensation system: air cooling tube bundle water collecting pipe, condensation tank (hot well of exhaust unit) and condensate pump

　　Vacuum-pumping system: vacuum pump or other air ejectors and the corresponding pipeline

　　Washing system: high-pressure water pump and washing unit

　　Electric instrument control: electrical and instrument control element in air cooling condensation system

　　2. Working principle of Direct Air Cooling System:

　　Exhaust steam from the turbine is sent into the exhaust steam unit and then sent into the heat exchange module for condensation and heat shielding. Air from outside of the tube is forced into the heat exchange module by the draught fan, absorbs heat and is then vented into the atmosphere. Condensation is collected in the condensation water tank under the steam exhaust device and sent to the next process through the condensation water pump. Non-condensable gas is vented by the vacuum-pumping unit.