Sustainable technology of wastewater treatment by environmentally friendly modified natural sorbents for removal of nitrogen and phosphorus

Abstract

The work deals with the issues of nitrogen and phosphorus removal from wastewater. Natural and modified sorbents: zeolite, glauconite, and bentonite were tested under laboratory conditions. The studies used effluent from biological wastewater treatment that contained an average concentration of 2.2 mg/L of ammonium nitrogen; 7.6 mg/L of nitrate nitrogen and 8.7 mg/L of phosphate phosphorus concentration. Wastewater (0.5 L) was mixed with sorbents (5 g) at a speed of 200 revolutions per minute, then nitrogen and phosphorus concentrations in the solution were measured. Natural glauconite and bentonite removed 58–60% ammonium nitrogen, while modified sorbents show higher 63–70% ammonium nitrogen removal efficiency, respectively. Clinoptilolite removed ammonium nitrogen from wastewater with 76% efficiency. The tested sorbents removed nitrate nitrogen with 14–15% efficiency and phosphate phosphorus with 19–45% efficiency.