Pre-Boiler Purification Technologies

Pre-boiler pretreatment is concerned with providing higher quality MU and FW—that is, water with most, if not almost all, natural impurities removed. There are perhaps as many interpretations of what constitutes high-quality water as there are boiler designs requiring it, and consequently there are also many specifications available, each with minor variations on a similar theme. Trying to decide precisely what is required, above and beyond a basic good quality, as provided by the use of pretreatment equipment such as filters, softeners, and so forth is difficult. 

A summary of some earlier notes indicates that boilers requiring higher quality MU and FW are  

This summary all but excludes FT boilers of any description from the requirement to have high-quality (i.e., low TDS) MU water. Exceptions are those FT boilers that have very low rates of CR and/or a high alkalinity MU water supply, and some special purpose boilers. 

Boilers of lower pressure rating that have significantly reduced rates of CR should operate with higher quality water (i.e., lower TDS) to avoid fouling and high BD rates. 

Boilers of any substantial pressure rating that receive MU water with naturally high alkalinity should incorporate a dealkalization plant as part of the pretreatment and purification plant. 

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