Distillation is the most widely used method in seawater desalination. Distillation method is relatively low in cost, and is mainly used for super-large seawater desalination treatment and places rich in heat energy. The essence of distillation desalination process is the formation of water vapor. Its principle is like that seawater is heated and evaporated to form clouds. Clouds cool under certain conditions to form rain, but rain is not salty. Seawater treatment companies generally adopt equipment distillation, steam compression distillation and multi-stage flash distillation.