Open-Recirculating Cooling Towers
Open recirculating systems provide the most common form of industrial cooling, continually recycling and reusing the same water to cool process equipment. In these systems, after water leaves the cooling tower, it is pumped to industrial applications using heat exchangers, condensers, air compressor jackets, or process reactors.
In this cycle, the water returning to the cooling tower water has absorbed excess heat which is then dissipated by passing the water over a water cooling tower where evaporation takes place. The cooling tower exposes the heated flowing water to air, causing a percentage (~1–3%) of the water to evaporate, which removes 1,000 BTU’s per pound of water that is evaporated. This cools the water that is not evaporated, which is then recirculated through the system.
Reusing cooling water results in water and chemical savings, as the chemistries are retained in the system. However, problems associated with corrosion, deposition, and microbial growths become more severe for several reasons. First, the process of evaporation concentrates the amount of dissolved and suspended solids in the circulating water, leading to deposition. Secondly, the warm temperatures in open recirculating cooling towers are optimum for biological growth. Third, water cooling tower operation tends to scrub airborne contaminants from the air which can accumulate in the circulating water, causing fouling and microbial growth.
ChemTreat field engineers have experience treating every kind of water cooling towers including natural draft, mechanical, cross flow, and counterflow cooling tower designs. Our staff average 18 years of experience, which helps them customize a solution for your specific system and work to find savings in the following areas:
- Increase heat transfer efficiency by eliminating heat exchanger fouling within heat exchangers with scale inhibitors
- Prevent fouling resulting from the precipitation of constituents, the settling of suspended matter, and microbial growth
- Reduce maintenance and plant downtime with corrosion inhibitors
- Maintain integrity of metal components by mitigating corrosion and pitting, that cause system failures.
- Increase cycles of concentration with proprietary chemical solutions
- Reduce the amount of makeup water and chemicals required and lower your sewer costs
- Maintain cooling tower water design efficiency with biocides
- Reduce microbial growth on the cooling tower fill resulting in an increased splash effect that maximizes air contact and increases evaporation rates