Biogas production from fiberbanks: combining sediment remediation and energy production (RemErgy)

The pulp and paper industry used to release large amounts of wood fibers into the aquatic environment.

Today this fibrous material is found as large banks of fibers on the seafloor (“fiberbanks”) in lakes and coastal areas in Sweden and in other countries. Large volumes of fiberbank sediments have been found in the few sites that have been surveyed so far. Despite being highly polluted, only a few fiberbank sites have yet been remediated in Sweden.

Greenhouse gas formation and release from fiberbanks is high, limiting in-situ capping remediation solutions and contributing to the global greenhouse gas emissions. Dredging followed by on-land treatment can therefore be a more efficient remediation action for fiberbanks.

In RemErgy we will explore the feasibility of a post-dredging remediation treatment of fiberbanks through anaerobic digestion which will also generate energy from the produced biogas.

Anaerobic digestion can enhance contaminant degradation, thus reducing the contamination levels in the sediment but also reducing its volume, while limiting non-controlled greenhouse gas emissions.

Biogas production from fiberbanks has been proved feasible, but some aspects still need to be improved, in particular regarding the efficiency of the anaerobic digestion and the degradation of contaminants. Several parameters will be tested in laboratory to provide an efficient biogas production from fiberbanks.