Abstract |
Field, pilot-plant, and theoretical studies show that asbestos-cement pipe can be used safely to transport drinking water provided that certain constraints, based on complicated chemical factors, are observed. Natural inhibitory factors, not calcite saturation, are the common protective mechanisms. Also, introduction of zinc compounds for in-situ pipe coatings promises to be an effective protection mechanism if the pipe has not deteriorated. Corrosion-control compounds often cannot correct pipe deterioration because the effectiveness of such methods depends on the quality of the surface of the pipe. The aqueous chemical model developed in this study for zinc solubility is also applicable to the dissolution of galvanized pipe and removal of zinc by carbonate and hydroxide precipitation. |