Shabnam Shabnam - Department of Chemical Engineering, Islamic Azad University, Science and Research Branch, Tehran,Iran
Majid Mohammadi - Department of Chemical Engineering, Amirkabir University of Technology (Tehran polytechnic),Tehran, Iran
Mehdi Sedighi - Department of Chemical Engineering, University of Qom, Qom, Iran

To remove nitrate ion from sample water, a pilot was designed and tested. The pilot drawers were filled with sawdust, wastewater of treatment plant, including the best strain, handmade nitrate solution, bentonite and twice washed sand. The experiments showed that the designed pilot in addition to the elimination of nitrate of the medium. In the case of the pilot performance of the continuous system andusing the strains taken from the wastewater of the treatment plant after the aeration phase, the nitrate and nitrite removal efficiency of the input of sample water in 20 minutes retention time were measured 74.84% and 99.8 respectively. It should be noted that through the pilot performance in all cases, pH and temperature had an increasing and decreasing trend respectively.

Nitrate ion removal; strain; sawdust; bentonite; yeast