Abstract

The present work evaluated the optimum concentration of microalgal cells for domestic wastewater treatment in terms of removal in nutrients and physicochemical parameters. In the study, three different concentrations (20, 30, and 40%) of microalgae was considered at 8 hours and 24 hours of Hydraulic Retention time (HRT). Among the different microalgal concentrations studied 30% microalgae concentration gave maximum removal at both the HRTs. The maximum removal efficiency of phosphate, ammonia and COD for the non-filtered sample was 87.67, 96.88, and 80.39%, respectively, for filtered sample it was about 91.32, 100, and 83.64%, respectively at 8 hours HRT. However, at 24 hours HRT maximum removal efficiency observed was 97.92, 92.22, and 93.47% for ammonia, COD and phosphate respectively in case of non-filtered sample whereas in filtered samples maximum removal efficiency was 100, 94.44, and 95.51% for ammonia, COD and phosphate respectively. From the study, it was found that microalgae can effectively remove nutrients and organic contents to desirable limits even at a low HRT of 8 hours. At the urban sector, if microalgae are incorporated in a conventional wastewater treatment system will enhance the cost-effective efficiency by lowering the HRT and increasing the removal efficiency with footprints of sustainable treatment.

摘要

目前的工作从去除营养物和理化参数的角度评估了用于生活废水处理的微藻细胞的最佳浓度。在这项研究中，在8小时和24小时的水力停留时间（HRT）时考虑了三种不同浓度（20％，30％和40％）的微藻。在研究的不同微藻浓度中，两个HRT的30％微藻浓度均达到最大去除率。未经过滤的样品的最大去除率分别为87.67％，96.88和80.39％，而HRT在8小时时分别为91.32％，100。％和83.64％。但是，在HRT的24小时内，氨的最大去除效率为97.92、92.22和93.47％，对于未经过滤的样品，COD和磷酸盐的去除率最高，而在过滤后的样品中，氨，COD和磷酸盐的最大去除率分别为100％，94.44和95.51％。从研究中发现，即使在8小时的低HRT时，微藻类也可以有效地将营养物和有机物去除到所需的水平。在城市地区，如果将微藻类纳入常规废水处理系统中，将通过降低HRT并通过可持续处理的方式提高去除效率，从而提高成本效益。