Water cooling towers are used in industries like power generation and oil refineries to enage in process cooling to remove heat via evaporation or closed loop cooling systems. While their usage is incredibly important to all of the different buildings and establishments they serve, many of them are also old and outdated, according to a recent piece from the Los Angeles Times.
In typical water cooling towers the circulation rate for a 700 MW coal-fired power plant amounts to about 71,600 cubic metres an hour (315,000 US gallons per minute) and a supply water make-up rate of approximately 5% (i.e., 3,600 cubic metres an hour) is required for circulation.
As the Los Angeles Times piece points out, Mayor Eric Garcetti recently launched the Drop 100 program, which aims to encourage business owners to invest in new or upgrade to their water cooling towers that will reduce overall water consumption by 100 million gallons of water per year.
It’s somewhat ironic that water cooling towers would be at the crux of an initiative to preserve water considering the unit’s origins. Cooling towers were developed to recycle more than 98% of wasted water, resulting in tremendous reductions in water and energy use as these systems grew in both popularity and size.
Unfortunately, as with everything else in the world things deteriorate as they get old. Today, many of these cooling towers that were innovative and efficient at the time are in need of improvements.
“In an efficient system, each gallon of water can cycle through the tower five or more times before being sent down the drain,” Doug Smith reported. “Eighty percent of the loss is due to evaporation. The worst systems have only one cycle. The water goes through the tower once and then down the drain.”
It’s a task about as tall as the world’s largest cooling tower, which stands at 663 feet and is located at the Kalisindh Thermal Power Station in Jhalawar, Rajasthan, India, but one that needs to be tackled.