The influences of polyaspartic acid alone

magnetic field alone，and their synergism on the crystal forms of calcium carbonate and the scale inhibition performance were investigated.The calcium carbonate crystal samples were characterized with SEM and XRD.The results showed that magnetized water treatment could increase the aragonite/calcite mass ratio in the deposited samples from 1∶3 to 1∶1.3 and the crystal phase of crystalline calcium carbonate was changed to vaterite almost completely，when polyaspartic acid was added.In addition，polyaspartic acid was able to chelat Ca2+ ion，which could be enhanced by the synergism of magnetic field and polyaspartic acid.A dynamic experimental device equipped with automatic heating and recycled water system was designed and assembled by the authors.The situation of calcium carbonate scale on the heat transfer surface was measured under different experimental conditions.Magnetic field and polyaspartic acid showed good synergism effect of scale inhibition and a scale inhibition rate of 69.5% was achieved whereas the scale inhibition rate in the magnetized water was 32.2% and that in the 3 mg·L-1 polyaspartic acid solution was 55.2%.