Polymeric Materials for Scale Inhibition in Cooling Water Systems

Calcium carbonate deposition is generally predominant in cooling water-circulating system. For the control of calcium carbonate, scale formation two types of polymeric scale inhibitors were used Polyamino polyether methylene phosphonate (PAPEMP) and polyacrylaminde (PAA).Model of cooling tower system have been built up in laboratory scale. Experiments were carried out using different inhibitor concentrations (0.5, 1, 1.5, 2, 3) ppm, at water temperature of 40oC and flow rate of 150 l/hr. It was found that Polyamino polyether methylene phosphonate more effective than polyacryle amide’ as scale inhibitor in all used concentrations and the best inhibition efficiency (95%) was at (2.5) ppm of Polyamino polyether methylene phosphonate and (85%) with polyacryle amide at concentrations of (3) ppm.The performance of the polymeric scale inhibitors was compared with a method used to control heavy calcium carbonate scale forming by the deposition of sufficiently thin protective calcium carbonate scale using sulfuric acid and depending on Ryznar stability index controlling method.