CONCO Field Notes:

Chemical Cleaning of Condenser Presents Extraordinary Challenge for Midwest Plant

 

As the table indicates, impurities with the highest concentrations include the hardness ions, calcium and magnesium (Ca+2 and Mg+2 respectively) and bicarbonate ions (HCO3-2).  All other natural water supplies have these ions, sometimes in lesser and sometimes in greater concentrations.  Often, managers, engineers and chemists at plants with once-through cooling systems may only give passing thought to scale formation in condensers.  This oversight can be costly because the water that comes in from the lake or river and is later discharged is not exactly the same.  Unlike familiar compounds such as table salt or sugar, calcium carbonate is less soluble as temperatures increase, so as the cooling water warms in the condenser or auxiliary heat exchangers, scale formation is a distinct possibility.  So was the case for a 1700 MW Midwestern coal-fired power station that recently began to have problems with calcium scale buildup...   Continue with story