Lignin to replace fossil bitumen in roofing felt - optimization of qualities and upscaling

Purpose and goal

This project aims to investigate which properties of the kraft lignin contribute to which properties in the roofing felt product, how this should be optimized to maximize bitumen substitution, and scale up the tests to demo scale with odor-reduced lignin which is a prerequisite for scaling up. The goal is to maximize bitumen replacement in roofing felt. Should lignin be able to replace 20% of bitumen in roofing felt and other renewable raw materials replace another 20%, it would mean a reduction of more than 50,000 tons of CO2 annually in the Nordic region.

Expected effects and result

By creating a roofing board product with a significantly lower content of fossil raw materials, this project contributes to the UN´s sustainability goals 9, 11, 12 and 13, by making available building materials that are more sustainable, by reducing the consumption of fossil oil and by increasing the utilization rate of the forest products that we already produce today. The environmental profile of the products will become an increasingly important feature in the competition and replacing fossil-based bitumen with bio-based lignin is an important step.

Planned approach and implementation

4 different lignin qualities will be tested in roofing felt. At least 4 different levels of involvement will be tested. The goal is to find a way forward to be able to maximize the degree of substitution of bitumen against lignin in the product. In this work, other renewable raw materials can also be tested together with lignin. Analysis of volatile organic compounds emitted during production will be carried out. Furthermore, analyses and tests on the products before and after aging will be carried out.