Correlating retention and drainage in papermaking with flocculation: effect of polyelectrolyte branching

Abstract

The effect of the degree of polymer branching on retention and drainage performance of flocculated kraft pulp fiber suspensions containing precipitated calcium carbonate (PCC) was investigated and has been correlated with flocs properties obtained by light diffraction scattering (LDS). The results show that polymers of medium charge density are more adequate to be used as retention aids since lower drainage time and higher filler retention are obtained at low flocculant contact time and low flocculant dosage. The results also demonstrate that it is possible to correlate the flocculation process evaluated by LDS with the flocculant’s performance in the drainage test.