Effect of Algal Cell Immobilization Technique on Sequencing Batch Reactors for Sewage Wastewater Treatment

Sequencing batch reactors (SBRs) are widely used for wastewater treatment for bioremediation of complex pollutants. The present study investigated the ability of algal cell immobilization technique (Chlorella vulgaris) in the improvement of SBRs during sewage wastewater treatment for 2 h before it reenters a non-fresh surface water bodies. The investigated sewage wastewater treatment plants were operating by biological treatment method (extended aeration) as an influent characterized with high nutrients (nitrogen and phosphate). The treatment efficiency of immobilization technique was 54% for (EC), 51% for (TDS), 59% for (TS), 97% for (TSS), 97% for (COD), 98% for (BOD), 98% for (O&G), 98% for (PO4), 98% for (NH3), and 91% for (T.N), and the pH value was 7.84. Also results revealed that the removal efficiency of differed heavy metals was improved by 57% of Cr, 54% of Fe, 56% of Ni, 53% of Cu, 67% of Zn, 100% of Cd, and 100% of Pb. The designing of SBRs with adding algal cell immobilization technique as the last step during treatment of plant influent significantly improved the quality of treated wastewater after only 2–6 h. The obtained results recommended upgrading of traditional operation systems via modern techniques, such as algal immobilization technique or use SBRs with algal cell immobilization.