Mist cooling system: An alternative to conventional cooling towers

By OEM Update Editorial September 11, 2018 4:04 pm IST

Water cooling has played an important role in all types of process industries and power plants since its inception. Efficiency of a process industry largely depends on availability of designed cold water temperature through-out the year, but mainly in summer and monsoon. During these months when humidity is high, cooling tower fails to achieve desired cold water temperature which results in lower efficiency of process/power plant, in turn resulting in loss of product. Now it is time’s need to find new solution to get desired cold water temperature throughout year.

The ultimate Mist cooling technology is the best alternative to conventional cooling towers. MCS can achieve an approach of 1 to 2C to WBT as against 5 to 6C approach for conventional cooling tower. Hence guaranteed cold water temperature of around 30C could be obtained throughout the year in our tropical climate. Also the spraying head is equivalent to the height of cooling towers thus requiring same pumping power. As mist cooling system does not require fans for cooling it saves huge amount of power. Also, as there are no moving parts involved in Mist cooling system the maintenance cost is negligible and system runs trouble free.

The ultimate Mist cooling system (MCS) is the one of the best option to conventional cooling towers. This advanced mist creation system can achieve an approach of 1 to 2C to WBT as against 5 to 6C approach for conventional cooling tower. Hence guaranteed cold water temperature of around 30C could be obtained throughout the year in our tropical climate. Also, the spraying head is equivalent to the height of cooling towers thus requiring same pumping power. As mist creation system does not require fans for cooling it saves huge amount of power. Also, as there are no moving parts involved in Mist creation system the maintenance cost is negligible and system runs trouble free.

Salient features of mist cooling system
Cold water temperature
Mist cooling system can ensure an approach of 0 to 1C to WBT with a temperature drop of 12 to 15C.

Energy savings
Due to such high temperature drop obtained, water quantity required at the process side is much less. MCS requires water pressure equivalent to the height of cooling tower. Hence, considerable amount of energy is saved on circulation water pumping. Also, MCS does not require any fans for cooling. Thus, a huge amount of energy is saved on circulation and cooling.

Process Benefits
Due to lower cold water temperature obtained from MCS, designed vacuum is maintained at the exhaust of the TG throughout the year, thus ensuring desired energy output at lowest possible steam consumption.

Maintenance
MCS has no moving parts. Also, the material used in the mist cooling system is special grade saran polymer, a highly non-corrosive material having a life of more than 10-15 years. This makes MCS absolutely maintenance free. As against this, cooling towers require a heavy maintenance in form of replacement of louvers, fan blades, clamps etc. every year.

MCS operates with a choke less design. Size of smallest opening in MCS is more than one inch (25 mm). Hence chances of particles choking the system are minimum.

Various designs of MCS to suit site conditions
A) Open Pond MCS
Here, MCS ensures an approach of 1 to 2C to WBT with T of 12 to 15C. Water loss due to drift is 0.1 to 0.25 per cent depending on wind load

B) Closed Pond MCS
Here MCS pond is closed from sides, up to a height of 7 to 11 meter by louver type cover sheeting. MCS ensures an approach of 2C to WBT with T of 12 to 15C. Drift loss comes down to less than 0.005 per cent and also space requirement reduces considerably.