EUBCE 2021 - Esa VAKKILAINEN - Use of HTC for Utilization of the Forest Industry Sludges

Use of HTC for Utilization of the Forest Industry Sludges


Sustainable Resources for Bio-Based Industrial Processing

Use of HTC for Utilization of the Forest Industry Sludges

Short Introductive summary

The objective of this study is to discuss properties and treatment of the forest industry sludges. Primary, bio- and tertiary sludges are side streams formed in the pulp mill wastewater treatment. Their disposal and reuse is challenging due to sludge properties. Tightening legislation regarding waste treatment and disposal, and the growing need to increase efficiency in all the unit processes of a pulp mill act as driving forces to find environmental-friendly and energy-efficient ways for sludge treatment. Currently, sludges are often combusted in mill’s boilers.

This study compares the currently used methods for primary, bio- and tertiary sludge handling in kraft pulp mills and presents two potential new methods, namely, biogas production and hydrothermal carbonization (HTC) and discusses their first industrial trials. These processes are also presented in more detail by introducing mill example cases and via reference mill calculations. The study shows that HTC process could transform the biosludge treatment process from an energy consumer into an energy producer.


Moderator portrait


LUT University, Laboratory of Sustainable Energy Systems

Presenter's biography

Current Organisation:Laboratory of Sustainable Energy Systems at LUT University
Currently Professor in Sustainable Energy Systems
2001-2009 Leading expert recovery, Pöyry Forest Industry Oy, Forest Industry Engineering, Recovery, Energy and Environment

Biographies and Short introductive summaries are supplied directly by presenters and are published here unedited


E K Vakkilainen, LUT University, Lappeenranta, FINLAND
K Kuparinen, LUT University, Lappeenranta, FINLAND
S Lipiäinen, LUT University, Lappeenranta, FINLAND

Session reference: IAV.7.13