Since air coolers were introduced into industrial service abroad in the 1930s, they have rapidly gained application in petroleum refining, petrochemical, and other industrial plants. They have been successfully used for services ranging from light oils to heavy oils and residuum, from positive pressure to negative pressure, from hot climates to cold regions, and from water-rich areas to water-scarce regions.
In the chemical industry, air cooling has been employed in processes such as ammonia synthesis, methanol synthesis, chlorides, PVC, and vinyl chloride monomer. For media that may explode upon contact with water, air cooling is particularly suitable.
In the power industry, due to water shortages, both direct and indirect air-cooling systems for steam-turbine exhaust are receiving increasing attention and are developing rapidly. In refineries and petrochemical plants abroad, the use of air-cooled condensers for drive turbines is also growing.
In the metallurgical industry, the application of air cooling technology has also progressed, and mature experience has been gained in air cooling of blast furnace circulating water.
Air coolers are also used as intercoolers for air compressors, recuperators for gas turbines, air coolers for generators, and waste heat recovery units. In refrigeration and air conditioning equipment, the condensation of refrigerants such as Freon, ammonia, or propane is often accomplished using small air coolers.
Air Cooler Advantages
|
No. |
Advantage |
|
(1) |
The installation site of the air cooler is not restricted by the availability of water source, water quality, or water intake conditions. |
|
(2) |
The layout and installation of the air cooler are not limited by the specific requirements of water supply and drainage facilities. |
|
(3) |
During operation, the allowable temperature rise range of the air cooling medium is larger than that of the water cooling medium. In addition, there is no issue of scale formation or corrosion of tube walls caused by cooling water. |
|
(4) |
In terms of maintenance, apart from regular inspection and lubrication, the air cooler does not require major disassembly or overhaul. Therefore, its operating cycle is longer than that of a water cooler. |
|
(5) |
In terms of equipment investment, because the required scale of water supply and drainage facilities is significantly reduced, air cooling is generally more economical than water cooling under normal operating conditions. |
|
(6) |
In terms of operating cost, under normal conditions, the power consumption (motor) of air cooled equipment is roughly equal to that of water cooled equipment. However, for more than 85% of the operating time, air cooling takes place at an ambient temperature approximately 10°C lower than the design temperature. Therefore, the actual power consumption of air cooling is generally considered lower than that of water cooling, with operating costs averaging about 50% of those of water cooling. Moreover, the maintenance cost of air cooled equipment is approximately half that of water cooled equipment. |
|
(7) |
In terms of capacity flexibility, compared to water cooling, air cooling offers significantly greater potential for increasing throughput. When expanding an existing plant, water cooling units can be replaced with air coolers. By using fans or motors, the processing capacity can be increased to a certain extent. |
