Chemicals added to the boiler water change the scale-forming salts into what?

The addition of chemicals to boiler water is a crucial part of maintaining the efficiency and longevity of the boiler system. When scale-forming salts are treated with the appropriate chemicals, they can be transformed into non-adhering sludge rather than simply remaining as scale deposits on the boiler's internal surfaces.

This non-adhering sludge is preferable because it doesn't stick to the boiler surfaces, reducing the risk of scale buildup, which can lead to overheating and damage to boiler components. By ensuring that the by-products of these chemicals remain in a suspended or dispersed state, the operational conditions of the boiler are improved, allowing for easier blowdown processes and better heat transfer efficiency.

The other options, while related to boiler water treatment, do not accurately reflect the outcome of properly addressing scale-forming salts. Adhering sludge would indicate that the material is still capable of accumulating on surfaces, which is not the aim of adding these chemicals. Soluble salts may simply dissolve in water without addressing the underlying issue of scale formation effectively. Heavy metals are not a direct product of chemical treatment for scale and are typically considered contaminants rather than desired outcomes.