Drag reducing polymer solutions: pumping effect

In this paper a number of flow experiments in pump flow with aqueous solutions of the polymers are presented. The high-molecular polymers studied were polyacrylamide of the molecular weights of Mv = 104 and 4.4×106 as well as carboxymethylcellulose sodium salt of the average molecular weights of Mw = 9×104; 2.5×105 and 7×105 and the substitution index ID = 0.9. The inlet solutions of the various mass fraction us Î (200; 1,000) ppm were exposed to degradation in a given time (4 weeks statically and dynamically when the flow time through the pump t = 0.5, 12h). The degradation in the closed flow system including pump UPE 25-60B, storage reservoir and tested flow installation, has been studied. It has been shown that the molecular weight of polymer decreases with increase of the exposition time. The pumping effect is stronger when the initial molecular weight of polymer is greater. The decrease of the non-Newtonian properties as well as the significant decrease of the drag reduction effect connected with the polymer time-degradation caused by the flow through pumps, have been observed.