MANAGEMENT OF SCALE DEPOSITS BY DIAMAGNETISM - A WORKING HYPOTHESIS

The basis for diamagnetism eliminating calcium carbonate deposits has been considered, and hypotheses include structure-forming forces, reduced mechanical strength of scale formed, effects on crystal size, and rates of nucleation. Another hypothesis, advanced here, is that a magnetic field of suitable strength imposes a Zeeman effect on a diamagnetic substance, and there is a concomitant increase in entropy (an increase in the number of available ''boxes''). The hypothesis was tested first with saturated aqueous magnesium hydroxide, and then with aqueous suspensions of calcium carbonate. The variation of pH in the presence and absence of a magnetic field followed the pattern predicted from the hypothesis: in the presence of a magnetic field for either system, the pH increased to a maximum value that remained constant. Removal of the magnetic field was accompanied by a slow (ca 17 hours) decrease in pH with time until the initial equilibrium pH was attained. Effects of carbon dioxide were minimized by using boiled deionized water and maintaining a nitrogen atmosphere during the experiments. Implications of the hypothesis and the tests are considered.