Redução do Índice de Saturação Langelier para produção de águas de consumo humano e industriais.

Abstract

Aiming at the issue of availability and water quality, the desalination of water through membrane processes is one of the alternatives to alleviate the problem of low quality and scarcity, producing good quality water. However, in this method there are still some obstacles to be overcome, one of them is the incrustation in the membranes. To solve this problem in reverse osmosis systems, commercial antifoulants are generally used, which are specific for particular salts. Among the ions commonly present in water are bicarbonate (HCO3-) and carbonate (CO32-), the latter easily found in the form of calcium carbonate (CaCO3), which under certain conditions precipitates, lowering the efficiency of the membrane and, consequently , The amount of water produced. Through the Langelier Saturation Index (ISL) it is possible to detect the risk of precipitation of this salt in brackish waters. This work describes the results of the research carried out in the study of water pretreatment for the reduction of ISL, comparing the performance of hydrochloric acid versus commercial antifoulant, Flocon 260. For this purpose, in this study initially used synthetic waters and later waters of Wells, performing tests on small and large scales. HCl proved to be a good antifouling since it was possible to obtain ISL values below zero for the two types of experiments, bench scale and pilot scale. For both types of water it was possible to observe good results and, when compared with the commercial antifoulant, a better cost-benefit ratio was observed.