Scale-inhibiting compositions and process for inhibiting scale in systems exposed to water

摘要

Compositions which inhibit the formation of scale due to calcium carbonate precipitation in recirculating water systems comprise a mixture of polyvinylpyrrolidone and ami- notri(methylenephosphonic acid). The compositions are preferably present in the water system in an amount from 2 to 25 ppm and preferably contain from 1 to 10 moles of the phosphonic acid per mole of polyvinylpyrrolidone.