A flocculant is a substance that promotes the clumping of particles so that they may be removed from water. Flocculants are essential in proper water treatment. One particularly popular flocculant is Ferric Chloride.
Ferric Chloride has been commercially available in the United States since the 1930's but it is only in the last 20 years that we've seen a trend of increased acceptance of Ferric Chloride for drinking water treatment. This trend is likely due to the chemical's improvements in product economics, quality and availability in the United States.
How Is Ferric Chloride Produced?
As one of the purest and most concentrated forms of iron commercially available for water treatment, Ferric Chloride has a unique distinction. In order to produce Ferric Chloride, Ferrous Chloride must be used. It is the oxidation of Ferrous Chloride with Chlorine that creates this new compound.
Using Ferric Chloride in the Water Treatment Industry
Ferric Chloride offers versatility in the water treatment industry, by working as a flocculant and coagulant, as well as a reactant. It promotes faster sedimentation in general and specifically, better sedimentation in cold water, making it an ideal choice for the industry.
Ferric Chloride has several applications in the potable water industry, including both high and low turbidity removal, enhanced coagulation, NOM (natural organic matter), DBP (disinfection by-products) precursor removal, color removal, arsenic reduction softening solids sedimentation aid, and as a filtration aid.
Safely Storing Ferric Chloride
It is extremely important that we handle Ferric Chloride, and all chemicals, with respect and in a safe manner. This holds true to safe chemical storage as well.
Ferric Chloride is also used as an etching medium, meaning it should not be stored in a FRP tank, as the chemical would compromise the tank. For safe storage, we recommend a high-density crosslinked polyethylene tank.
Ferric chloride is also a high fuming chemical. These fumes can potentially defoliate surrounding trees and plants.

When storing Ferric Chloride in a chemical storage tank, a fume-tight manway lid cover prevents fumes from escaping the tank. Adding a scrubber provides a cost-effective solution to address any potential fuming into the atmosphere while using ferric chloride.
Our crosslinked polyethylene tanks are able to store up to 96% concentration of Ferric Chloride, with a tank that has a specific gravity rating of 1.65, with PVC fitting materials, EDPM gaskets, and titanium bolts.