An alternative cooling water program has been developed to replace chromate. Ultra low levels of zinc (0.5-2.5 ppm) have been determined to provide near comparable results in many applications to the chromate type programs. The new program has a wide application range for calcium (15 to 1000 ppm as CaCO3) and pH (7.3-9.0).
88-11: An Alternative Cooling Water Treatment Program for the Replacement of
Guy A. Crucil & Ronald H. Schild, Nalco Chemical Co.