Isibika A, Simha P, Vinnerås B, Zurbrügg C, Kibazohi O, Lalander C
Department of Energy and Technology, Swedish University of Agricultural Sciences, Box 7032, 75007 Uppsala, Sweden; Department of Chemical and Mining Engineering, College of Engineering and Technology, University of Dar es Salaam, P.O. Box 35131, Dar es Salaam, Tanzania.
Department of Energy and Technology, Swedish University of Agricultural Sciences, Box 7032, 75007 Uppsala, Sweden.
Sci Total Environ. 2023 Feb 1;858(Pt 3):159985. doi: 10.1016/j.scitotenv.2022.159985. Epub 2022 Nov 9.
Black soldier fly larvae composting is an emerging treatment 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 fly larvae (BSFL) 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 (~100,000-1,000,000 kg y). 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 ≥10/12 as the most suitable feedstock for BSFL composting. However, multi-criteria analysis based on physical-chemical criteria identified brewery waste and sunflower press cake with total score points of ≥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 BSFL-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.
黑水虻幼虫堆肥是一种新兴的处理方式，有望改善低收入国家城市中生物废弃物的价值转化。本研究调查了坦桑尼亚三个城市（达累斯萨拉姆、姆万扎和多多马）食品工业生物废弃物的产生及管理现状，以及它们作为黑水虻幼虫（BSFL）堆肥处理潜在原料的可用性和适用性。研究发现，这三个城市中产生生物废弃物的食品工业公司（n = 29）大量生产香蕉皮、芒果籽、向日葵榨油饼、啤酒厂废弃物和咖啡壳（约100,000 - 1,000,000千克/年）。其中约50%的公司（16/29），主要是植物油公司（10/11），将其废弃物作为动物饲料出售或赠送，而大多数产生未利用食品工业废弃物的公司（9/11）则将产生的生物废弃物填埋。基于底物可用性标准的多标准分析确定，总分≥10/12的香蕉皮、芒果籽和咖啡壳是最适合BSFL堆肥的原料。然而，基于物理化学标准的多标准分析确定，总分≥11/15的啤酒厂废弃物和向日葵榨油饼是最适合的原料。各生物废弃物的综合可用性和物理化学性质表明，所有确定的食品工业生物废弃物类型都可以作为生产用于蛋白质生产的BSFL生物量的合适原料，但某些废物流在进行BSFL堆肥之前需要与其他废物流混合，以确保有足够的可用性，并与单一来源的生物废弃物相比提供均衡的营养成分。本研究得出结论，坦桑尼亚的食品工业公司产生了大量的食品工业废弃物，需要建立新的生物废弃物管理干预措施以实现资源回收。此外，对于废物管理业务中有兴趣的利益相关者来说，多流BSFL堆肥可能是管理和闭合坦桑尼亚及全球其他类似环境中未利用食品工业生物废弃物营养循环的合适解决方案。
