How electrolysis can help ...
Published by KRISTOF BOSTOEN, IRC International water and sanitation Centre - Senior Programme Officer
How electrolysis can help reducing TDS!
Dear Anneliese, Total Dissolved Solids (often abbreviated TDS) is a measure of all inorganic and organic substances contained in water in molecular, ionized or micro-granular (colloidal sol) suspended form. The operational definition is solids that are small enough to pass a two-micrometer filter. Part of these dissolved solids are salts and metals allowing water to have a slight conductive behaviour. If such water get in contact with metals a natural electro-chemical process called electrolysis will occur. This process can dissolve or remove parts of the solids from the water. Corroding ductile iron pipes for example introduce iron ions in the water. When water is heated, this electrical process can be accelerated which is for example a problem for water heaters.
The natural electrolysis can be reversed and accelerated by forcing an opposite current with a sacrificial anode. This controlled electrolysis can reduce certain solids in the water reducing the overall TDS but there is more to it than just running a current and having an sacrificial anode to ensure the desired effect. You need the right chemical reaction adapted to your water and environment.
Good luck
K.