1:Operational principle
OPEN TYPE
Open type cooling tower, fan operating pulls fresh air which inlets from the bottom side of the cooling tower, up through the PVC fills media and to the top, while pressurized spray nozzles spray water downward in the opposite direction of the airflow. (The PVC fills is located above the dry air inlet and beneath the spray nozzles and runs the entire width of the cooling tower.) Air flow and water flow run in parallel with one another, but in opposite directions. Air flow take away the heat from water flow, then be exhausted by the top fan.
CLOSED TYPE
Closed type cooling tower, the hot working fluid inlet from the cooling coils, then the waste heat be took away by the fall down spray water and reverse flow with the cold fresh air which inlets from the bottom of the tower and form to saturated vapor in the process. Air flow takes away the heat from spray water, then be exhausted by the top fan and the water is collected to bottom tank and circulate continuously by the special evaporator.
2:Performance comparison
Open type | Closed type |
1:Open system, the fluid is cooled directly by spray, the water quality tends to deteriorate. Should do cleaning work frequently, also easy to cause pollution to supporting equipment and pipelines. | 1:Water flowing in a closed system,It can make heat ex-changer and pipelines not easy to scale,pollution and corrosion, increase the service life of supporting equipment. |
2:High floating rate, high water consumption, And easy to cause pollution to the environment around the equipment. | 2:The circulating water is almost no water consumption. For equipment with the same heat transfer effect, the closed tower saves about 2-3% circulating water every year compared with the open tower. |
3:Another underground pool needs to be dug. Due to water drop difference and open head loss, more electricity is consumed than closed tower and more electricity is consumed. | 3:Water Basin inherent at the bottom. |
4:Service life: 3-5 years. | 4:Service life: 10-15 years. |
5:The cost of open tower is relatively low, one third of the price of closed tower. But needs high operating cost. | 5:Closed cooling towers cost three times as much as open ones. But with low operating cost, and obsolete equipment can be recycled. |
