One of the main challenges with using flat panel photobioreactors for algal growth is uneven mixing and settling of cells in corners, especially when bubbling is the only method used for mixing. In order to improve mixing in our flat panel reactor, we designed a custom paddlewheel. Paddlewheels are frequently used in outdoor algae raceway ponds to improve mixing and we are taking advantage of the same principle for mixing in the reactor. The paddlewheel is easily integrated into our PSI FMT150 1-L flat panel photobioreactor and is printed on a 3D printer using high temperature poly lactic acid (HT-PLA). With the inclusion of an annealing step, the paddlewheel is autoclavable. Addition of the paddlewheel in the reactor minimized cell settling and improved algal growth, as evidenced by a nearly 40% increase in oxygen production rates. Nutrient dispersion and utilization in the culture was also improved as evidenced by a corresponding 38% decrease in CO₂ concentration. The paddlewheel device presented here is a cost-effective method for improving algal growth in a flat panel photobioreactor.

中文翻译：

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定制 3D 打印叶轮可改善平板光生物反应器的生长

使用平板光生物反应器进行藻类生长的主要挑战之一是角落中细胞的不均匀混合和沉降，特别是当鼓泡是唯一用于混合的方法时。为了改善平板反应器中的混合，我们设计了定制桨轮。室外藻类跑道池经常使用明轮来改善混合，我们利用相同的原理在反应器中进行混合。该桨轮可轻松集成到我们的 PSI FMT150 1-L 平板光生物反应器中，并使用高温聚乳酸 (HT-PLA) 在 3D 打印机上进行打印。由于包含退火步骤，明轮可进行高压灭菌。在反应器中添加桨轮可最大限度地减少细胞沉降并改善藻类生长，氧气生产率提高近 40% 就证明了这一点。_{CO 2}浓度相应降低了 38%，证明了培养物中养分的分散和利用也得到了改善。这里介绍的桨轮装置是一种经济有效的方法，用于改善平板光生物反应器中的藻类生长。