| 摘要 |
914,701. Preventing corrosion and scaling. PROGIL. March 12, 1959 [March 12, 1958], No. 8594/59. Class 123 (1). A process for protecting the metal surfaces in an open water circuit, that is, a circuit in which there is no recycling of water already treated, against corrosion or against both corrosion and scaling comprises intermittently injecting into the water circuit up to and including a total at each injection of fifty parts by weight of a water-soluble orthophosphate and/or a water-soluble polyphosphate per million parts of water, the frequency of the injections being such that the average amount of phosphate injected does not exceed five parts per million. The preferred phosphate is sodium hexametaphosphate used alone or admixed with sodium orthophosphate. A quantity regulating pump controlled by a time switch may be used to inject the phosphate. |
