Water Treatment Programme Chemicals

Neutralising (volatile) amines travel with the steam and dissolve in the condensate, where they neutralise carbonic acid formed from carbon dioxide and raise condensate pH. Filming amines instead lay a thin, water-repellent film on pipe walls that shields the metal from carbonic acid and oxygen. Neutralising amines suit systems where carbon dioxide attack is the main problem; filming amines help where oxygen also enters the return lines. Combined treatments use both mechanisms together.

Catalysed sulphite reacts quickly with dissolved oxygen and is widely used in low- and medium-pressure boilers, but it adds dissolved solids to the boiler water and is not suited to high-pressure units. Hydrazine adds no dissolved solids and also helps form a protective magnetite layer on steel, so it is used mainly in high-pressure boilers. Hydrazine is toxic and needs careful handling, and it is generally avoided where steam contacts food. The choice depends on pressure, feedwater quality and steam use.

Both kill microbes as hypohalous acids, but hypochlorous acid dissociates into the much weaker hypochlorite ion as pH rises, so chlorine loses most of its strength above about pH 8. Hypobromous acid stays largely undissociated at pH 8 to 9, so bromine performs better in alkaline towers and in water containing ammonia, where bromamines remain active. Many programmes also alternate an oxidising biocide with a non-oxidising one, such as an isothiazolinone, to broaden control.

No. Most RO and nanofiltration membranes are polyamide thin-film composites that are damaged by free chlorine, so feed water is dechlorinated and biofouling is controlled with a non-oxidising biocide such as DBNPA. Acidic cleaners remove carbonate scale and iron or other metal oxide deposits; alkaline cleaners remove organic fouling, biofilm and silt. Always stay within the membrane manufacturer's pH and temperature limits for cleaning.

HEDP and ATMP are widely used general-purpose inhibitors of calcium carbonate scale in cooling water. DTPMP holds up in high-hardness, high-alkalinity water and is also used against barium and strontium sulphate scale in oilfield water. PBTC has the highest calcium tolerance of the group and good stability against chlorine and bromine, so it suits high-pH, high-cycle towers on oxidising biocides. Tolyltriazole or benzotriazole is added when copper or brass is present.

Send the make-up water analysis (hardness, alkalinity, silica, chlorides and TDS), the boiler type and operating pressure or the cooling tower's circulation rate and cycles of concentration, the metals in the system, and your expected monthly use. The product and grade are matched against these details before we quote, and the quotation confirms packaging, lead time and terms in writing.