关键词: 旋转磁场, 成核, 结晶, 结垢, 脱盐, 耦合关系

Abstract:

With environmental issue being increasingly emphasized, anti-scaling methods without chemical additives gradually raises more concern over researchers. Some researchers consider magnetic treatment as a physical anti-scaling method that has the advantages of non-pollution and low cost. However, its effectiveness and mechanism in industrial applications still remain controversial. Wide range and narrow range magnetic treatment devices are newly designed, taking calcium carbonate crystal system as research object, to study the coupling relationship between magnetic treatment effect and the volume of treating water which are both closely related to industrial application. The results show that when the amount of treating water is small, magnetic treatment can promote the homogeneous nucleation of calcium carbonate, resulting in more crystal particles with smaller size and greater total deposition. In a certain speed range, magnetic treatment effect is enhanced with the increasing speed of rotating magnetic field.There is a clear coupling relationship between the rotating magnetic field and water volume:when the magnetic treatment conditions remained unchanged and the amount of water to be treated increased,magnetic treatment effect would be weakened; when the water volume treated remained unchanged and magnetic treatment condition strengthens, magnetic treatment effect would be enhanced. Stepwise magnetic treatment experiment with a part of solution which is going through magnetic treatment first and then gradually adding more can improve the removal rate of calcium carbonate in a large amount of water, and make the magnetic treatment effect more obvious. At the same time, the importance that matching water volume with magnetic field was illustrated.

Key words: rotating magnetic field, nucleation, crystallization, scaling, desalination, coupling relationship