REQUIREMENTS water chemistry
USED ​​FOR MANUFACTURING AND heat transfer processes.
Requirements for the chemical composition of process water are determined by the use of specific processes. The greatest amount of water consumed in the heat exchange apparatus for allocating excess heat. Only to compensate for water loss in the circulating water systems separate companies spend tens or even hundreds of thousands of cubic meters of water per day. In terms of the current systems of multiple heating water to 40 - 45 ° C and cooling it in the basin lead to the loss of carbon dioxide and deposition on the surfaces of heat exchangers and tubes of calcium carbonate.
At high constant rigidity of recycled water due to the content of calcium sulfate, evaporation of water in the cycle may exceed the solubility product of calcium carbonate (solubility of the latter decreases with increasing temperature) and the formation of solid carbonate deposits, whose removal from pipes and heat exchangers are extremely difficult.
The rate of deposition of calcium carbonate and other salts should not exceed 0.25 g / (m2-h). Therefore, the basic requirement for water consumed in the current recharge systems is the restriction of carbonate and sulfate stiffness.