Wroclaw University of Science and Technology, Department of Process Engineering and Technology of Polymer and Carbon Materials, Wyb. Wyspińskiego 27, 50-370 Wroclaw, Poland
Wroclaw University of Science and Technology, Chair in Water and Wastewater Treatment Technology, Wyb. Wyspiańskiego 27, 50-370 Wroclaw, Poland
The municipal wastewater from a medium-sized town in the Lower Silesia Province of Poland was treated by several methods. They included filtration through ceramic, 300 kDa or 50 kDa, polymer membranes, 5 or 30 kDa, sedimentation, and nanofiltration membranes with a cut-off 200 Da (NF90), 400 Da (NF270), and 300-500 Da (NFW). The character of all streams at each stage of the treatment process was determined by detecting the chemical oxygen demand, total nitrogen, and phosphorus. Concentration of sodium, calcium, magnesium, and potassium ions was also detected after the purification process. The best treatment parameters were achieved in the case of using a combination of ultrafiltration on 50 kDa ceramic membrane and nanofiltration on NF 90 polymeric membrane. It was a determined reduction in total nitrogen by a factor of 3, phosphorus by a factor of 9, and a decrease in sodium from 101.47 mg/L to 21.58 mg/L in the final permeate.