Category Marine Technology


Electrochlorination is a process used by water companies to destroy or render harmless disease-causing microorganisms in tap water. It is also used in third-world countries and at the site of natural disasters to disinfect the water supply, therefore helping to decrease the risk of water-borne diseases.

The need for a method of disinfection for water became apparent in the early 1900s, when the connection between water contamination and deadly diseases such as typhoid fever, dysentery and cholera became more obvious. Water processing plants began implementing chlorination between 1905 and 1910. The death rate from typhoid fever decreased dramatically after water chlorination began, dropping from over 240,000 deaths in 1900 to zero deaths by 1960, according to statistics from U.S. Centers for Disease Control and Prevention. Water chlorination was called “the most significant public health advance of the millennium” by Life Magazine and has virtually removed the threat of these often-fatal diseases from the United States.



While water chlorination decreases illness-causing bacteria, it also has its drawbacks. Chlorine is a gas when at room temperature and has a strong, irritating odor like that of bleach. Chlorine does not easily ignite, yet it can combine with other chemicals to create highly volatile compounds. While chlorine can cause burns on the skin, it is extremely harmful when swallowed or inhaled. Because chlorine reacts with water to form an acid, it will wreak havoc on the cells of the body, leading to corrosion of the cells where contact was made.



Electrochlorination is a form of desalination that is commonly used to disinfect water and to make it safe for using in swimming pools and as drinking water. Electrochlorination is among the most earth-friendly methods of treating water. Unlike other chlorination methods, electrochlorination does not generate any sludge, toxic fumes or corrosive gases.

Electrochlorination is performed by the desalination of salt water to produce a chlorinated solution. A salt water solution, either synthetic brine or sea water, is first placed in electrolyzer cells that contain an anode (positive electrode) at one end and a cathode (negative electrode) at the other end. A direct electrical current is then sent through the brine solution. The chloride ions in the solution oxidize at the anode in the electrolyzer, producing chlorine gas. The reaction at the cathode produces sodium hydroxide and hydrogen gas. The newly-formed chlorine then reacts with the sodium hydroxide to form the solution sodium hypochlorite. The simple formula for this reaction is: NaCI + H2O + DC electricity = NaCIO + H2. Sodium hypochlorite formed “on-site” by electrochlorinators has several advantages over chlorine gas and commercially produced sodium hypochlorite.

• Easy to store
• Requires fewer safety measures than chlorine gas-based systems
• Can be created “on-site” with very low operating costs
• Does not degrade over time like its commercial counterpart
• Non-toxic to humans and to the environment
• pH range of 6-7.5, making it relatively neutral

Electroclorination System

The electrochlorination process can be used almost anywhere in the world and is a safe, effective alternative to conventional water chlorination methods. Learn more about electrochlorination @ Cathodicme.

Marine Engineering Wiki: Do You Know What Sacrificial Anodes Are and How They Work?

Read More