When using a tube heat exchanger, a white substance will stick to the inner and outer walls of the heat exchanger, forming a sticky substance, which we call scale. How do you maintain this scale?
In fact, we all know that ordinary water contains certain calcium and magnesium salt compound ions with relatively small solubility in water. They all have a common characteristic, that is, the solubility decreases as the water temperature increases. This feature is still common, and the salt in the sediment will have insoluble characteristics. When the water temperature in some containers is heated, a large amount of salt substances will be deposited, so we will see such a white salt, that is, scale.
When scale adheres toTube and tube heat exchangerAfter that, we know that the relative thermal conductivity of scale is actually very poor. Generally, the thermal conductivity of this kind of scale is smaller than that of steel.30 ~ 50times, so we will feel that the temperature sensing performance of a section of heat exchanger with scale will become very poor. Experimental performance of temperature data results in a decrease in thermal conductivity with increasing temperature.
After corresponding experiments, we will have such a characteristic, that is1mmThick scale will decrease relatively10%. In the direction of the heat transfer surface, it is found that it is difficult to be relatively clear, similar to the increased cost of related maintenance, which not only consumes manpower, but also loses material resources, so that we will feel that the heating surface usually does not rise to the effect we want, and the cycle performance will become very poor.