用壳聚糖絮凝法采收小球藻及上清液再利用的研究

摘要

针对工业化培养小球藻Chlorella vulgaris时存在的采收困难以及后续上清液的循环利用问题,设计了培养小球藻的新型循环模式,具体操作步骤为:用气升式反应器培养小球藻→加入壳聚糖絮凝→过滤藻体得上清液→在上清液中补加营养成分→加入气升式反应器中再用于培养小球藻.结果表明:在5次小球藻循环培养中,后4次循环培养藻体的生长速率和收获期浓度均比第1次培养的稍高；用壳聚糖作为絮凝剂时其絮凝效果较好,且未产生絮凝抑制性；每次循环时在上清液中定量补加营养成分,NO3--N、PO43--P含量变化均在无抑制积累的范围内.说明利用壳聚糖作为絮凝剂采收小球藻的效果及利用上清液循环培养小球藻的效果都比较理想.%A new recycling mode to culture green alga Chhrella vulgaris was designed to solve the difficulties in harvesting and recycling of the supernatant. The concrete procedures included the alga culture with air-lift reactor, flocculate by addition of chitosan, collection of the supernatant through filtration, addition of nutrients into supernatant, and putting supernatant into air-lift reactor to culture further. The result showed that there were slightly higher growth rate and harvest levels of the algae in the next four cycles compared to the first cycle of the alga culture. The flocculation of chitosan was found to be effective, without inhibition. The supernatant supplemented with quantitative nutrients, nutrients representative NO3- -N, PO43- -P content were accumulated in the absence of inhibition within each cycle. In conclusion, the effect of chitosan flocculation and the recycling supernatant harvested for the alga culture is quite acceptable.