1: There is no calcium and magnesium ions in soft water, corrosion and rust will occur under the action of chloride ions, iron ions will corrode and rust under the action of oxygen ions, and trivalent iron ions and hydrogen molecules will be produced under the action of hydrogen ions to corrode and rust.

The heat transfer coefficient of scale is 0.464-0.697W/(m.k), which is only about 1% of carbon steel. When the surface of the metal body is covered with dirt, it will seriously hinder the heat transfer capacity of the metal and directly lead to a sharp decline in the overall performance of the system. This is the most direct reason for the increase in system energy consumption.

According to the data provided by the U.S. Department of Energy’s "Non-Chemical Technology Mode and Hardness Control"

Dirt: Dirt is mainly composed of organic matter in water, microbial colonies and secretions, sediment, dust, etc. The texture of the dirt is soft, which not only reduces the heat transfer efficiency, but also causes corrosion under the dirt.