Increasing the lipid production rate stands as one of the challenges for achieving economic feasibility of microalgal biorefinery. Various bioreactor operation strategies have been considered for culturing microalgae, including batch, continuous, fed-batch, semi-batch, and two-stage operations. However, since the previous studies used different experimental criteria, it is hard to draw a conclusion about their relative performances. Motivated by this, the present study compares lipid productivity performances and capital expenditures of the various operation strategies after their operating conditions are optimized. The optimal condition for each strategy is determined by performing a model-based optimization to maximize lipid productivity, which is a good indicator of the overall economics. The two-stage operation with continuous-batch serial connection (w/ stress condition) and the semi-batch operation (w/o stress condition) show outstanding performance compared to the other types of operation. Also, start-up, initial cell concentration, and chemical consumption, which are critical factors in large-scale cultivation, are analyzed.

提高脂质生产率是实现微藻生物精炼厂经济可行性的挑战之一。已经考虑了用于培养微藻的各种生物反应器操作策略，包括分批，连续，补料分批，半分批和两阶段操作。但是，由于先前的研究使用了不同的实验标准，因此很难就其相对性能得出结论。因此，本研究比较了优化操作条件后各种操作策略的脂质生产率性能和资本支出。通过执行基于模型的优化以使脂质生产率最大化来确定每种策略的最佳条件，这是整体经济性的良好指标。与其他类型的操作相比，连续批量串联连接的两阶段操作（无应力条件）和半批量操作（无应力条件）显示出卓越的性能。此外，分析了启动，初始细胞浓度和化学消耗，这是大规模培养的关键因素。