Heat Exchanger Scale Removal
Mechanical cleaning provides a force greater than the dirty adhesion to remove dirt adhering to the surface. This cleaning method removes carbonized dirt and hard scale that cannot be removed by chemical methods. The methods of mechanical cleaning can be divided into the following two categories:
(1) Strong cleaning. The strong cleaning method uses the spraying device to spray the medium into the tube side and the shell side of the heat exchanger with a very high impact force, which serves the purpose of descaling. Common strong cleaning methods include shot blasting, high pressure water jet cleaning, jet cleaning, sand blast cleaning, and strong pipe cleaners. Among them, the high-pressure water jet cleaning is mostly used to remove carbonized scale or hard scale, and for the dirt which cannot be removed by relying on the impact force and must rely on heat to loosen it, steam jet cleaning is used.
(2) Soft mechanical cleaning. This cleaning method relies on the movement of the insert in the tube to contact the tube inner surface to achieve the effect of removing dirt.
This soft mechanical cleaning is also called online mechanical cleaning. Common methods include rotary spiral method, liquid-solid fluidization method, rotary link method, spiral spring vibration method, and sponge rubber ball online cleaning method.