Effect of drag reducing polymers on the rate of mass transfer in relation to their use as corrosion inhibitors in pipelines under turbulent flow conditions

Rates of mass transfer between a turbulently flowing fluid containing CMC drag reducing polymer and the wall of a tube were measured in the mass transfer entry region using the electrochemical technique. Variables studied were polymer concentration, surface roughness and solution flow rate. Carboxymethyl cellulose (CMC) was found to reduce the mass transfer coefficient by an amount ranging from 15 to 37% depending on the operating conditions. The percentage decrease in the mass transfer coefficient becomes greater with increasing CMC concentration and Reynolds number. CMC was found to reduce the rate of mass transfer at rough surfaces (e super(+) > 3) by an amount higher than that at a smooth surface. The possibility of using large polymers as drag reducers and corrosion inhibitors simultaneously in pipelines is indicated.