The inability of organic coagulants to purify potable water to its best attainable quality

Abstract

Organic coagulants have gained increasing popularity over the past 30 years because they are considered cheaper and more user-friendly than traditional mineral hydrolysing coagulants. Regrettably, in-depth studies have not yet been conducted on their ability to purify water to a healthy palatable drinking quality which is risk-free for lifetime consumption in terms of the national standard for drinking water quality of various countries worldwide, and does not become a source of secondary pollution in the reticulation system. The objective of this paper is to provide information about the natural organic matter (NOM) removal efficiency attained at different waterworks purifying water with different organic coagulants, and to compare this with that attained using mineral coagulants. The findings presented in this article prove that organic coagulants are not an equivalent replacement for mineral coagulants, as the purified water is of an inferior quality which does not comply with the limits set by national standards of different countries worldwide.