Page 298 - Corrosion Engineering Principles and Practice
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Means of Treatment Coagulation, settling, and filtration. Softening. Demineralization. Internal boiler water treatment. Surface active agents. Lime and lime soda softening. Acid treatment. Hydrogen zeolite softening. Demineralization. Dealkalization by anion exchange. Neutralization with alkalies. Aer
Difficulties Caused Imparts unsightly appearance to water. Deposits in water lines, process equipment, and so on. Interferes with most process uses. Chief source of scale in heat exchange equipment, boilers, pipelines, and so on. Forms curds with soap, interferes with dyeing, and so on. Foaming and carry over o
Chemical Formula None—expressed in analysis as units. Calcium and magnesium salts expressed as CaCO 3 − ), Bicarbonate (HCO 3 2− ), carbonate (CO 3 expressed as CaCO 3 H 2 SO 4 , HCl, expressed as CaCO 3 CO 2 (H + ) 2− ) (SO 4 Cl −
Constituent Turbidity Hardness Alkalinity Free mineral Acid Carbon dioxide pH Sulfate Chloride TABLE 8.5
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