Abstract

Hydrothermal carbonization (HTC) can be used to break down sludge structure and generate carbonaceous hydrochar suitable for solid fuel or value-added material applications. The separation of char and the reaction medium however generates a filtrate, which needs to treated before potential discharge. Thus, this work determined filtrate properties based on HTC temperature and sludge moisture content and estimated the discharge emissions and the potential increase in analyte loads to an industrial wastewater treatment plant based on derived regression models. Direct discharge of HTC filtrate would significantly increase effluent emissions at the mill, indicating the filtrate treatment is crucial for the future implementation of HTC at pulp and paper mills. Recycling the HTC filtrate to the wastewater plant would lead to only a nominal increase in effluent flow, but would increase the suspended solids, BOD, COD and total nitrogen loads by 0.1-0.8%, 3.8-5.3%, 2.7-3.1% and 42-67%, respectively, depending on HTC temperature.

Keywords

Biosolids; Experimental design; Hydrothermal treatment; Multiple linear regression; Principal component analysis; Wastewater treatment

Published in

Bioresource Technology
2018, Volume: 263, pages: 654-659
Publisher: ELSEVIER SCI LTD

SLU Authors

• Mäkelä, Mikko

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    
  • Aalto University

• Larsson, Sylvia

  • Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Ensure sustainable consumption and production patterns


UKÄ Subject classification

Bioenergy


Publication identifier

DOI: https://doi.org/10.1016/j.biortech.2018.05.044

Permanent link to this page (URI)

https://res.slu.se/id/publ/96144