Research at the BTC

Last changed: 10 June 2021

The research at BTC focuses on processes that simplify the use of bio-based by-products so that it becomes easier for industries to opt-out of fossil alternatives. By developing knowledge in the interface of inherent raw material properties and the downstream processes, we can design pretreatment methods to tailor industrial feedstock and create functional components for new products.


Upgrading or refining generally means processing to reach desired qualities. Examples of desired qualities are; high density or concentration of the desired content (i.e. energy or chemical component), good handling and storage characteristics, and absence of process disturbing compounds/contaminations, etc. As an example, stem wood has a relatively high quality in terms of homogeneity. On the other hand, it has high moisture content. Other raw materials, i.e. straw, have significantly higher ash contents, but may not require drying before processing. Through the right upgrading actions, side-products from bio-based industries may be transformed into valuable feedstock. 


Upgrading bio-based materials usually includes one or several steps of drying. Raw materials from the forest have a moisture content of about 50 %, and industrial side-products are sometimes even wetter. For many industries, drying is a necessary and expensive process. At BTC, we are equipped with several different drying techniques, both as research tools, and to enhance material preparation.

Comminution and fractioning

The material preparation chain at BTC can transform whole logs, bales, or truck loads of raw materials to well-defined chips, chops, or powder in one or several fractions. These actions are of uttermost importance in the upgrading chain. By means of sieving and fractioning, valuable components can be extracted from a complex source of raw material. Methods for maximizing the yield of valuable components are important in the biorefinery concept.  

Compaction to pellets and briquettes

At BTC we have advanced systems for performing experimental research designs for production of pellets and briquettes from a wide range of feedstock, feedstock mixes and additive blends. Research results from the pilot scale setup have been shown to correspond well to industrial scale pelletizing conditions and have been directly implemented. Hence, process optimization can be performed in designed experiments with well-defined materials and under controlled conditions at low cost.  

Thermal conversion

BTC has a thermal conversion laboratory in which combustion characteristics of pellets can be studied; particle and gas emissions, ash characteristics, and ash melting behavior.