Effect of cathode current density on scale generated by electrochemical scale removal technique

Scale samples generated by different cathodic current densities were characterized by scanning electron microscope and the X-ray diffraction method to analyze their surface morphology and polymorph composition. The results show that the electrochemical treatment would greatly change the scale morphologies and crystalline form. The scale sample changed from pure calcite powder without electrolysis to the mixed powder after electrolysis, in which the aragonite form was dominant. The mass fractions of aragonite form in the mixed powder were 90.23% and 82.65% for the samples generated at 15 A/m² and 20 A/m², respectively, more than 69.37% for the sample generated at 50 A/m². Moreover, the morphology of the samples was quite different. These results indicate that the cathodic current density can not only influence the macro effect of scale removal treatment, but also change the micro morphology, the structure, and the composition of the generated scale.