Chemical Pulping

Raw material handling

While industrial wood chips may seem homogeneous, they are in fact composed of large and small chips, chips of odd sizes and shapes, as well as chips with varying color. However, uniform chip quality and size matters. For example, large-sized chips pulp more slowly than smaller chips and this difference has a significant impact on pulp quality and yield, digester performance, as well as many downstream fiberline operations. Our goal is to gain a better understanding of how the chemical pulping process can be improved through better chip quality.

Pulping and biomass fractionation

Pulping is a process that extracts fibers from wood, most commonly this is carried out in pulping industry either by kraft or sulfite processes. In addition, there are emerging biomass fractionating technologies, which are based on “green” solvents, such as Deep Eutectic Solvents (DESs). These processes are currently often combined with fractionation processes to separate and valorize lignin, tall oil, and turpentine. Our research projects aim at optimizing pulping and biomass fractionation processes, also by improving the industrial process control strategies.

Pulp bleaching

The bleaching of chemical pulps is carried out with chemicals containing chlorine or oxygen. Typically, a pulp bleaching operation involves the use of more than one bleaching agent due to the complex structure and nature of lignin. Bleaching of chemical pulps involves the use of chemicals which are more specific to lignin removal. Moreover, bleach plants consume large quantities of water and discharge substantial volumes of effluent. Our research projects aim at improving bleaching concepts for lower environmental impact, while still maintaining high cost-effectiveness.