Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, 50130 Mikkeli, Finland.
Department of Environmental and Biological Sciences, University of Eastern Finland, Yliopistonranta 1E, 70211 Kuopio, Finland.
Bioresour Technol. 2022 Nov;363:127912. doi: 10.1016/j.biortech.2022.127912. Epub 2022 Sep 8.
Microalgae can add value to biological wastewater treatment processes by capturing carbon and nutrients and producing valuable biomass. Harvesting small cells from liquid media is a challenge easily addressed with biofilm cultivation. Three experimental photobioreactors were constructed from inexpensive materials (e.g. plexiglass, silicone) for hybrid liquid/biofilm cultivation of a microalgal-bacterial consortia in aquaculture effluent. Three light regimes (full-spectrum, blue-white, and red) were implemented to test light spectra as a process control. High-intensity full-spectrum light caused photoinhibition and low biomass yield, but produced the most polyhydroxybutyrate (PHB) (0.14 mg g); a renewable bioplastic polymer. Medium-intensity blue-white light was less effective for carbon capture, but removed up to 82 % of phosphorus. Low-intensity red light was the only net carbon-negative regime, but increased phosphorus (+4.98 mg/L) in the culture medium. Light spectra and intensity have potential as easily-implemented process controls for targeted wastewater treatment, biomass production, and PHB synthesis using photosynthetic consortia.
微藻可以通过捕获碳和营养物质并生产有价值的生物质来为生物废水处理过程增值。从液体介质中收获小细胞是一个挑战，可以通过生物膜培养轻松解决。使用廉价材料（例如有机玻璃、硅酮）构建了三个实验性光生物反应器，用于在水产养殖废水中混合培养微藻-细菌共生体的混合液体/生物膜。实施了三种光照制度（全光谱、蓝白和红），以测试光光谱作为过程控制。高强度全光谱光会引起光抑制和低生物质产量，但会产生最多的聚羟基丁酸酯（PHB）（0.14mg/g）；一种可再生的生物塑料聚合物。中等强度的蓝白光对碳捕获的效果较差，但可去除高达 82%的磷。低强度的红光是唯一的净碳负体系，但会使培养基中的磷增加（+4.98mg/L）。光光谱和强度有可能成为用于目标废水处理、生物质生产和使用光合共生体合成 PHB 的简单实施过程控制。
