After pre-treatment, the final balancing of chemicals into the boiler is important to its operation, safety, and the health of the steam system. Two points need to be initially addressed that will reduce chemical consumption and wasted energy from boiler blowdown - the boiler feedtank temperature should be kept at ~ 85°C to minimise the dissolved oxygen and potential thermal shock to the boiler, and the plant should have a maximum of condensate returned if possible.
The chemical treatment program will cater for system variables such as feedtank temperature and condensate return rate, as well as raw water quality and water pre-treatment. In turn, it will determine the required chemicals, optimal dosing rates and locations. Our experts will work with your boiler operator to ensure that the program works as effectively as possible.
Chemicals provided will help your boiler and system in a number of ways:
Minimise Oxygen- oxygen scavengers such as sulphites, chemically remove oxygen from the water to avoid pitting corrosion on surfaces.
Minimise Scale – antiscalents are used to react with feedwater ions to prevent these forming scale on the boiler surface. Specialised polymers are used and loose deposits are removed by bottom blowdown.
pH control – typically boiler water pH should be maintained at elevated pH levels to avoid corrosion. Alkalinity levels in the boiler (which are sometimes stripped in pre-conditioning) can be controlled by the addition of hydroxide-based chemicals.
Reduce Foaming – this can be minimised by controlling the suspended solids (TDS) and using anti-foam chemicals that modify the liquid surface.
Protect downstream acid attack - corrosion inhibitors, such as neutralising amines, deal with the corrosive effects of carbon dioxide in steam which turns into carbonic acid in the condensate system.