Hence if the in the evaporator is heated to a temperature below 80ccalcium sea water carbonate If it is heated above 80°C magnesium hydroxide scale scale predominates. is deposited. If the contents is in excess of 96,000 pp.m. (332) calcium density of the evaporator sulphate but evaporator density is normally 80,000 pp.m. (24/32) scale can be formed, and to calcium sulphate should be no problem. less, hence scale formation due