| 摘要 |
PURPOSE: To inhibit the deposition of calcium sulfate scale and to disperse iron by adding a scale inhibitor containing a water-soluble organic phosphonate and an N-substituted acrylamide polymer having a specified amide structure in a specified weight ratio. CONSTITUTION: The pH of a feedstream is controlled to 6.0-7.0, the temperature is controlled to 50-80 deg. F and a scale inhibitor is added to the feedstream in an amount of about 0.002-0.005 ppm per ppm hardness (as CaCO3 ) of the feedstream. The scale inhibitor preferably contains a water-soluble organic phosphonate and an N-substituted acrylamide polymer having an amide structure represented by the formula [where R2 is H or methyl, R1 is H or alkyl, R is alkylene or phenylene and X is sulfonate (poly)hydroxyl, (poly)carboxyl or carbonyl and a combination of those] in a polymer to phosphonate weight ratio of 0.2:1 to 6:1. |
