Department of Environmental Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, U.P., India.
Department of Chemistry, Manav Rachna University, Faridabad, Haryana, India.
J Environ Manage. 2019 Feb 1;231:562-569. doi: 10.1016/j.jenvman.2018.09.096. Epub 2018 Oct 30.
An experimental study was performed to evaluate the comparative efficiency of bio-flocculant (waste egg shell), laboratory available calcium carbonate (LACC) and alum (Al (SO)) for harvesting of unicellular microalga, Chlorella pyrenoidosa. The influence of pH on zeta potential (ζ) was also studied to explain the chemistry of flocculation process. The maximum harvesting efficiency (99%) was obtained with alum with deformities in algal cell surfaces. Waste egg-shell material is developed as a low-cost bio-flocculant for harvesting of Chlorella pyrenoidosa using 100 mg egg-shell bio-flocculant/L and 100 mg LACC/L, zeta potential analysis was completed to further understand the chemistry of harvesting efficiency over the different ranges of pH (2.0, 4.0, 6.0, 8.0, and 10.0). The optimized range for harvesting efficiency (HE) of pH is 4.0-8.0 for both flocculants. Maximal harvesting efficiency was achieved at pH 4.0 (99%) and pH 8.0 (95%) with bio-flocculant and LACC respectively. Hence, bio-flocculant based harvesting method is found as the best way to dewatering the algal biomass from aqueous medium with entire and intact algal cell surface with environment friendly and cost-effective approach.
进行了一项实验研究，以评估生物絮凝剂（废蛋壳）、实验室可用碳酸钙（LACC）和明矾（Al（SO））在收获单细胞微藻、椭圆小球藻方面的相对效率。还研究了 pH 对 ζ 电位的影响，以解释絮凝过程的化学原理。使用 100mg 蛋壳生物絮凝剂/L 和 100mg LACC/L，明矾获得了 99%的最大收获效率，同时使藻细胞表面变形。废物蛋壳材料被开发为一种低成本的生物絮凝剂，用于收获椭圆小球藻。完成了 ζ 电位分析，以进一步了解在不同 pH 值范围（2.0、4.0、6.0、8.0 和 10.0）下的收获效率的化学原理。对于两种絮凝剂，收获效率（HE）的最佳 pH 值范围为 4.0-8.0。生物絮凝剂和 LACC 分别在 pH 4.0（99%）和 pH 8.0（95%）时达到最大收获效率。因此，基于生物絮凝剂的收获方法被发现是一种从含水介质中脱水藻类生物质的最佳方法，其具有完整和完整的藻细胞表面，且具有环境友好和经济有效的方法。
