Chemicals for water and wastewater treatment

Treating water is a sequence of chemical decisions. Colloids are destabilised with a coagulant, gathered into settleable floc with a polymer, filtered, disinfected and finally protected against scale and corrosion in pipes, boilers and cooling towers. Each step has its own reagent family, and each family has grades that suit drinking water, process water or effluent.

Products by treatment stage

• Clarification. Aluminium sulfate, polyaluminium chloride, ferric chloride and polyacrylamide flocculants.
• Disinfection. Sodium and calcium hypochlorite and trichloroisocyanuric acid.
• Scale and corrosion control. HEDP, ATMP and sodium hexametaphosphate.
• pH and dechlorination. Hydrated lime and sodium bisulfite, plus activated carbon for taste, odour and organics.

Most of these are listed under Inorganics and Metals and Specialty Chemicals. Plant laboratories can order hardness, alkalinity and residual chlorine reagents, indicators and buffers from Lab Reagents.

Approvals and logistics

If the water is for human consumption, tell us the standard your authority applies. Some producers hold potable-use approvals and others do not, and we confirm this before quoting. Hypochlorites are oxidisers with strict stowage rules, so we plan their packing and routing separately from acids and organics.