CORROSION IN COOLING WATER SYSTEMS: A foremost topic at the Effluent and Water Treatment Convention Available to Purchase

The word polyelectrolytes bobbed up ubiquitously at Earls Court during the Convention sessions held from March 30 to April 2. The thread‐like nature of the ionised molecules of these materials, and their other principal advantage of water‐solubility, are finding more and more uses in clarifying, sedimenting, thickening, sludge filtration and dewatering operations. Polyacrylamides of MW 105–5 X 106 are among the more recent types used for controlling mud and silt in cooling systems, the dosage being 0.05–200 p.p.m.