Principle and efficiency of physical anti-scaling treatments

摘要

For many years, a great deal of research has been carried out on anti-scaling devices. However their efficiency in authentic situations is still controversial and difficult to appreciate and quantify. Scaling of pipes and water distribution installations results from the precipitation of calcium carbonate (Ca CO_3) on walls or at their immediate neighbourhood. The growth of such scaling layers from the walls can induce problems in the functioning or operation of the installations. The principle of physical treatment is to produce microscopic nuclei of calcium carbonate that to conserve their anti-scaling effect must remain as suspended solids in the solution. Thermodynamically, the growth of those germs is easier than the precipitation on a wall and consequently the precipitation will occur mainly on the suspended germs, reducing the scaling risk at the walls.