What floats on the surface of boiling hot water? Is it harmful to human body?

Scale, the main component of scale is calcium carbonate, which has no effect on health, but it will affect the kettle.

Scale, commonly known as "scale, water alkali", refers to the white block or powdery substance gradually formed after the minerals contained in hard water attach to containers (such as pots and kettles). The main components are calcium carbonate, magnesium hydroxide, magnesium carbonate, calcium sulfate, magnesium sulfate, calcium chloride and magnesium chloride.

Scale has poor thermal conductivity. If the scale formed in the boiler is too thick, it will reduce the efficiency of the boiler, and even cause the boiler to burst and cause boiler accidents.

Scale classification

(1) can be divided into carbonate scale, sulfate scale, silicate scale and mixed scale according to chemical composition. The main components of carbonate scale are calcium carbonate and magnesium carbonate; The main components of sulfate scale and silicate scale are calcium sulfate and silicic acid compound respectively; Mixed scales are mostly a mixture of the above three scales.

(2) According to the classification of physical properties, there are two kinds: scale firmly bonded to the drum wall and tube wall and loose and easy-to-fall sediment.