基于泡沫浮选的能源微藻采收实验研究

Research on harvesting energy microalgae via foam flotation

文章以十二胺作为捕收剂,利用泡沫浮选法采收能源微藻——小球藻。利用正交实验研究了捕收剂用量、搅拌转速、藻液浓度、溶液p H和浮选时间对小球藻采收效率的影响。结果表明:捕收剂用量、搅拌转速、藻液浓度对采收效率影响显著,p H和浮选时间对采收率影响较小;十二胺能显著增加小球藻细胞的可浮性,较高的搅拌转速和藻液浓度有利于提高藻细胞与气泡的碰撞粘附效率。综合考虑采收率和采收成本,在不调节藻液浓度和p H的情况下,泡沫浮选法采收小球藻的最优条件为十二胺用量为30 mg/L、搅拌转速为1 200r/min、浮选时间为3 min,此时采收率可达到98.35%。

In this study, Chlorella as a promising biofuel resource, was cultured and harvested using foam flotation. The effects of the dosage of collector （dodecylamine）, stirring speed, the concentration of Chlorella, the pH of culture solution, and the flotation time on the harvesting efficiency were detailed investigated using orthogonal experiment. The results showed that the pH of culture solution and the flotation time had little effect on the harvesting efficiency; however, the dosage of collector, stirring speed, and the concentration of Chlorella exerted significantly positive effect on the harvesting efficiency. This promotion was attributed to the following reasons： the addition of collector （dodecylamine） can enhance the floatability of Chlorella cells; the high stirring speed and the high concentration of Chlorella can promote the collision and adhesion efficiency between Chlorella cells and bubbles. Considering the harvesting efficiency and the cost, with the constant concentration of ChloreUa and the pH of culture solution, the optimum parameters were set as 30 mg/L of dodecylamine, 1 200 r/min of the stirring speed, and the 3 min of the flotation time. The harvesting efficiency can reach up to 98.35%.