微藻生物采收技术的现状和展望

Status and prospects of microalgae harvesting with biological flocculation

微藻是一类重要的光合微生物,在能量转化和碳循环中举足轻重。目前,微藻生物技术主要应用在固碳控污、生物质能源、食品、医药、饲料及其他高附加值产品制备等方面。但仍有很多技术瓶颈亟待解决,其中,微藻采收的高能耗是阻碍微藻产业化发展的主要原因之一。由于微藻在培养液中浓度低、粒径小,传统的沉降、过滤、离心等采收方法都存在效率低或成本高的限制。利用絮凝性藻类、细菌、真菌或者从微生物中提取的生物絮凝剂收获微藻的生物采收技术由于具有安全、无二次污染、采收率高、设备投入和运行能耗与其他方法相比显著降低等优点,目前被认为是最具前景的采收技术之一。系统地评价了不同微藻采收技术的优缺点,并重点阐述了微藻生物采收技术的研究进展及前景。

Microalgae are important photosynthetic microorganisms playing important roles in energy conversion and carbon cycle. At present,algae biotechnology is mainly used in carbon fixation and pollution control,production of bio-energy,food,medicine,feed,and other value-added by-products,etc. However,there are still many technical bottlenecks need to be addressed such as energy-intensive microalgae harvesting,which is one of the main obstacles that hinders microalgae industry. Traditional harvesting methods such as sedimentation,filtration,and centrifugation are either of low efficiency or high cost for microalgae harvesting due to low concentration in medium and the relatively small size of microalgal cells. Biological flocculation method,mediated through flocculating algae,fungi,bacteria and/or microbial flocculants extracted from microorganisms,is considered as one of the most promising techniques for algae harvesting due to advantages of high safety,high recovery efficiency,low fundamental investment,low operating energy consumption,and no secondary pollution to the environment,etc. This paper critically reviewed different microalgae harvesting methods with particular focus on the current status and prospects of biological flocculation.