MAGNETICALLY AUGMENTED WATER-TREATMENT

A test rig was constructed to investigate the effect of orthogonally a pplied magnetic fields on solutions of calcium carbonate and accompany ing changes in scale deposits formed from solution. The rig employed r ecirculated calcium carbonate solutions, which were passed through mag netic fields of strengths up to 7000 Gauss. Scaling occurred on a copp er heat exchanger surface at temperatures set at between 40 degrees C and 60 degrees C. Changes in solution chemistry, zeta potential and pa rticle size were also investigated. Scale deposits were analysed by sc anning electron microscopy. Results showed that magnetic treatment had a significant effect on the precipitation/deposition of calcium carbo nate from solution under controlled physico-chemical conditions. Scali ng was affected by the system temperature, pH and degree of supersatur ation. The magnetic field was shown to influence significantly the zet a potential and particle size distribution of particles formed in solu tion, as well as the crystal morphology of the calcium carbonate depos its. This paper presents a summary of laboratory results and relates t hem to a possible mechanism.