Using slaughterhouse waste in a biochemical-based biorefinery – results from pilot scale tests

ABSTRACT

A novel biorefinery concept was piloted using protein-rich slaughterhouse waste, chicken manure and straw as feedstocks. The basic idea was to provide a proof of concept for the production of platform chemicals and biofuels from organic waste materials at non-septic conditions. The desired biochemical routes were 2,3-butanediol and acetone–butanol fermentation. The results showed that hydrolysis resulted only in low amounts of easily degradable carbohydrates. However, amino acids released from the protein-rich slaughterhouse waste were utilized and fermented by the bacteria in the process. Product formation was directed towards acidogenic compounds rather than solventogenic products due to increasing pH-value affected by ammonia release during amino acid fermentation. Hence, the process was not effective for 2,3-butanediol production, whereas butyrate, propionate, γ-aminobutyrate and valerate were predominantly produced. This offered fast means for converting tedious protein-rich waste mixtures into utilizable chemical goods. Furthermore, the residual liquid from the bioreactor showed significantly higher biogas production potential than the corresponding substrates. The combination of the biorefinery approach to produce chemicals and biofuels with anaerobic digestion of the residues to recover energy in form of methane and nutrients that can be utilized for animal feed production could be a feasible concept for organic waste utilization.

KEYWORDS:

• Platform chemicals
• biofuels
• anaerobic digestion
• fermentation
• organic waste

Acknowledgements

Fadi Atif Fakhir and Henny Andersson, Mälardalen University and Prof. Yuying Li, Nanyang Normal University, are acknowledged for their assistance in the experimental tests. The authors also wish to thank Anneli Heitto, Finnoflag Oy, for the participation in the pilot plant tests. Hagby Gård, Enköping, Sweden is acknowledged for providing the site for the pilot plant and for providing the feedstock for the pilot runs.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCiD

Sebastian Schwede http://orcid.org/0000-0002-5014-3275

Eva Thorin http://orcid.org/0000-0002-3485-5440

Johan Lindmark http://orcid.org/0000-0002-8268-1967

Patrik Klintenberg http://orcid.org/0000-0003-2189-0105

Ari Jääskeläinen http://orcid.org/0000-0002-5119-4365

Anssi Suhonen http://orcid.org/0000-0003-1198-9419

Reino Laatikainen http://orcid.org/0000-0003-4377-2740

Elias Hakalehto http://orcid.org/0000-0003-2883-590X

Additional information

Funding

The study was part of the ABOWE project, funded by the European Union (European Regional Development Fund) [grant number 2007CB163PO020]. Construction of the Pilot A was co-funded by the Regional Council of Pohjois-Savo and the Ministry of Employment and Economy in Finland.