Study on the rheological properties of fast-growing eucalyptus

To study the effect of retention and drainage aids on the fast-growing eucalyptus bleached kraft pulp (EBKP) suspensions, different concentrations of cationic polyacrylamide (CPAM) and cationic starch were dosed with EBKP suspensions and their effects on rheological properties were studied. The shear yield stress (τy) of softwood bleached kraft pulp (SBKP) and poplar alkaline peroxide mechanical pulp (PAPMP) were compared and evaluated for their potential applications. The results show that in the steady-state shear condition, the τy of EBKP is proportional to the pulp mass concentration (Cm), corresponding to the exponential relation . SBKP had the highest τy values, followed by EBKP and PAPMP. Adding CPAM and cationic starch to EBKP suspensions at low to moderate doses increased the τy, but once the levels reached a certain point, the τy values began to deteriorate. This research is crucial to achieve optimally and stabilize the downstream manufacturing process in papermaking.