Sustainable ideas, Keep them coming


A cooling tower dissipates the heat created from industrial processes by removing the heat by

evaporating some of the water by allowing the water to contact the air. The water which has absorbed the heat for the process is discharged by evaporation with the air which leaves out of the top of the tower. The cooled water returned to the process to be reused.

Water lost during the evaporative process

As a result of the evaporative process some of the water is lost. Therefore, make-up water is used to replace the lost water.  The normal sources of water loss in the cooling tower other than evaporation include blowdown which is removes some of concentrated water and drift, where the droplets of water are released into the air.  The remaining water is routed via a circulation pump for reuse.

A suggestion was made to recover this water which evaporated by finding a way to capture the water and minimize the amount wasted while maintaining the efficiency of the evaporative process.

How much is water lost during evaporation

After completion of the mass balances for the air and water used in the cooling tower typically only 5% of the water is lost as a result of evaporation.

Any equipment created to recover the water, while being sustainable would have little impact since relatively small amount of water which would be able to be saved. For example, a cooling tower with a 500 ton heat load flowing 1500 gallons per minute (gpm) through its condensers which in turn would evaporate 12 gallons per hour.

This idea did not work but…

Perhaps this particular idea did not wind up being feasible. But the next one might.

Keep in mind every invention started as an idea. Example, the creation of first xenon compounds resulted from a scientist who studied the ionization energies of these compounds and realized these molecules had enough energy to create xenon compounds but his colleagues scoffed at the idea since xenon is an inert gas and would be not able to form compounds. The scientist later proved these xenon based compounds were possible once he produced the first compounds of this type.

So Keep ‘em coming.

So keep the ideas coming as the next far-fetched one assumed to be impossible might actually work. What ever happened to the Canadian scientist?

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