Boiler steam system

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Why does silicon dioxide generally not deposit in superheaters? In boilers of high pressure and above, steam has a very strong capacity to dissolve and carry silicon compounds, often much higher than that of mechanical transport. However, other silicon-containing sodium salts can be ignored almost entirely because their distribution coefficients are much lower than that of silicon dioxide. Therefore, in boilers of high pressure and above, the silicides in the steam are carried in dissolved form, primarily as silicic acid. Silicic acid loses water in the superheated steam to form silicon dioxide. When heated in the superheater, the solubility of silicon dioxide increases further; even though silicon dioxide is in a supersaturated state in saturated steam, it becomes unsaturated once it reaches the superheater. Thus, silicon dioxide generally does not deposit in superheaters.