DISINFECTION AND DISINFECTION BY-PRODUCTS: A NUISANCE IN DESALINATION TECHNOLOGY1

To overcome the problem of water scarcity and facilitate social development of the nation, Saudi Arabian Government was unprecedented in pioneering and unparalleled in expanding seawater desalination industry. One of the diverse utilities of desalinated water is its use for drinking and other related domestic purposes. In the latter case, it is obviously of dire importance to ensure a safe water supply. For this reason desalinated water has to be treated with some suitable disinfectant before dispensing it the consumer. Almost all desalination plants in the Kingdom of Saudi Arabia use chlorine as the disinfectant of choice. Most of these plants produce their own chlorinating agent by electrolysis of seawater to generate chlorine, which is allowed to react with co-generated sodium hydroxide to form sodium hypochlorite. This seawater generated sodium hypochlorite, NaOCl (SW), is dosed to product water in the form of crude chlorinating agent contained in the parent seawater matrix. Thus, there is always a fear that the carrier seawater matrix becomes charged with disinfection byproducts, DBPs, which may contaminate product water. The DBPs of concern were, i