Selection of Cooling Water Treatment at Military Installations to Prevent Scaling and Corrosion.
Abstract
This report offers solutions for scaling, corrosion, and fouling problems in cooling tower systems at Army and Air Force installations. These problems are caused by dissolved minerals in the water and growth of algae or slime within the system. The scaling product (SP) of cooling tower water can be expressed as a product of the calcium hardness (Ca) and alkalinity (M) expressed as CaCO3. The SP of water at major U.S. Army Training and Doctrine Command and U.S. Army Forces Command installations varies from 504 to 45,640. The State of Illinois has tested recently developed treatment products made by commercial enterprises. The simplest method of cooling tower treatment is blowdown control. A reciprocating cooling tower evaporates 1.5 gallons of water per hour per ton (5.67 l/0.9 MT), while an absorber evaporates 3 gal/hr/ton (11.12 l/0.9 MT). The blowdown rate equals the evaporation rate divided by, cycles of concentration minus 1. The makeup water equals the amount of evaporation plus blowdown. The maximum cycles of concentration are limited by the scaling chemicals in the water; it is considered uneconomical to run less than 3 cycles of concentration. For cooling towers less than 20 tons (18.1 MT), the water should be air cooled or passed once only. For cooling towers of 20 to 50 tons (18.1 to 45.3 MT), 3 cycles of concentration with sodium hexametaphosphate (0.5 to 5 ppm) should be used
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1980
- Accession Number
- ADA087266
Entities
People
- Avinash Kumar
- R. Lane
Organizations
- Construction Engineering Research Laboratory