Abstract

Black soldier Ily larvae composting is an emerging treannent option with potential to improve biowaste valorization in cities of low-income countries. This study surveyed the current generation and management status of food industry biowaste and their availability and suitability as potential feedstock for black soldier Ily larvae (BSFI.) composting treatment in three Tanzania cities, Dar es Salaam, Mwanza, and Dodoma. Biowaste-generating food industry companies (n = 29) in the three cities were found to produce banana peels, mango seeds, sunflower press cake, brewery waste, and coffee husks in large quantities (similar to 100,000-1,000,000 kg y(-1)). Around 50 % of these companies (16/29), primarily vegetable oil companies (10/11), either sold or gave away their waste as animal feed, while most companies (9/11) with unutilized food industry waste landfilled the generated biowaste. Multi-criteria analysis based on substrate availability criteria identified banana peels, mango seeds, and coffee husks with total score points of a >= 10/12 as the most suitable feedstock for BSFL composting. However, multi-criteria analysis based on physicalchemical criteria identified brewery waste and sunflower press cake with total score points of a >= 11/15 as the most suitable feedstock. Combined availability and physical-chemical properties of individual biowastes showed that all identified types of food industry biowaste can be suitable feedstock for producing BSFL biomass for protein production, but certain waste streams needed to be mixed with other waste streams prior to BSFL-composting to ensure sufficient availability and provide a balanced nutritional profile compared with the single-source biowastes. This study concluded that large volumes of food industry waste are being generated from food industry companies in Tanzania and there is need to establish new biowaste management interventions for resource recovery. Furthermore, for interested stakeholders in the waste management business, multi-stream BSFI.-composting can be a suitable solution for managing and closing nutrient loops of the unutilized food industry biowaste in Tanzania and in other similar settings globally.

Keywords

Organic waste management; Cities; Low-/middle-income countries; BSFL composting; Biowaste availability

Published in

Science of the Total Environment
2023, Volume: 858, number: Part 3, article number: 159985
Publisher: ELSEVIER

SLU Authors

• Isibika, Alice

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    
  • University of Dar es Salaam

• Simha, Prithvi

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Vinnerås, Björn

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Zurbrügg, Christian

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    
  • Eawag, Swiss Federal Institute of Aquatic Science and Technology

• Lalander, Cecilia

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

End hunger, achieve food security and improved nutrition and promote sustainable agriculture
Strengthen the means of implementation and revitalize the global partnership for sustainable development
Ensure sustainable consumption and production patterns


UKÄ Subject classification

Environmental Management


Publication identifier

DOI: https://doi.org/10.1016/j.scitotenv.2022.159985

Permanent link to this page (URI)

https://res.slu.se/id/publ/120969