Phosphonates as additives in kraft pulp

Yield improvement with HEDP (1-Hydroxyethylene-1,1-di-phosphonic acid) addition to the Kraft digester is caused by improved cellulose retention. Hemicellulose content at given yield is not significantly affected. Physical properties of HEDP treated pulps were comparable or slightly improved as compared to the control. Maple demonstrated a less pronounced response to HEDP addition than aspen. At given cooking conditions KAPPA number reductions of 3-4 points and yield improvements of 1-2% could be observed. An additional component of this project aims to examine the market applicability of this innovation. At this point development of a conceptual framework of technology adoption in the Kraft pulping industry and a qualitative survey instrument for use in exploratory interviews is presented. Pulp & paper mills operating in Minnesota, Wisconsin, Michigan and Ontario (Canada) have been selected for potential inclusion in this phase.