Chip impregnation

MoRe Research has installed pilot equipment aimed at real time studies of the wood chip impregnation process. It is integrated with MoRe’s pilot digester plant and used to study how wood chip is impregnated and cooked under various conditions. Studies can be conducted for paper pulps and dissolving pulps. The impregnation pilot is a result of a PhD work at Helsinki University and has been further developed by MoRe.

Impregnation studies are of interest for all chemical pulping processes irrespective of if the end-product is pulp for paper or board production or dissolving cellulose. Not least it is useful when pulp mills want to increase production or have problems due to insufficient impregnation.

This unique pilot equipment is developed during a PhD work at Helsinki University. The wood chips are placed in the pilot’s basket and the impregnation process is monitored when the chip weight increases as air is gradually replaced by cooking liquor in the chips. The original pilot has been developed further by MoRe and adapted to the existing pilot digester plant in order to facilitate combined impregnation and cooking studies. Impregnation studies can be done for different chips sizes, tree species, temperatures and pressure conditions as well as for different chemical pulping processes.

“We have bought the pilot as it is a perfect match for our unique pilot digester plant,” says Michael Sjögren, Process Consultant at MoRe Research. “This method allows us in a realistic way to study the impregnation process before cooking. As the pilot is integrated with our digester plant we can in a realistic way simulate the whole impregnation and cooking process for a customer and achieve relevant results. An optimised way of running the process with customer specific variables can therefore be set.”

Apart from customer specific projects it is also useful in research projects, one example is Jessica Gard Timmerfors’ present PhD work concerning optimised chip cutting in the MCS pilot drum chip cutter for sulphite pulp.

For more information, please contact Michael Sjögren, E-mail, mobile +46 70 572 87 20.