What effect does TOC (Total Organic Carbon) have on RO and NF membranes?
Organics in RO and NF feed water can adsorb onto the membrane surface and cause a flux loss. Organics occuring in natural waters are usually humic substances in concentrations between 0.5 and 20 ppm of TOC (Total Organic Carbon). Pretreatment should be considered when the TOC exceeds 3 ppm. Humic substances can be removed by a coagulation process with hydroxide flocs, by ultrafiltration, or adsorption on granulated activated carbon (GAC).
