University of Tehran/Springer International Journal of Environmental Research 1735-6865 7 1 2013 01 01 Denitrification via Nitrite in a Modified UASB reactor using Chilean zeolite as Microbial Support 17 26 582 10.22059/ijer.2012.582 EN L. Guerrero 1Department of Chemical and Environmental Engineering, Federico Santa Mar1a Technical University, Ave. España 1680, Valpara1so, Chile M. Vasquez 1Department of Chemical and Environmental Engineering, Federico Santa Mar1a Technical University, Ave. España 1680, Valpara1so, Chile A. Barahona Department of Chemical and Environmental Engineering, Federico Santa Mar1a Technical University, Ave. España 1680, Valpara1so, Chile S. Montalvo Department of Chemical Engineering, Santiago de Chile University, Ave. Lib. Bernardo O’Higgins 3363, Santiago de Chile, Chile R. Borja Instituto de la Grasa (CSIC), Avda. Padre García Tejero, 4, 41012-Sevilla, Spain Journal Article 2012 12 13 The general objective of this study was to develop a highly efficient, economical and<br />integrated technology for the removal of nitrogen compounds through denitrification via nitrite. To<br />achieve this, a modified UASB reactor was designed, set-up and operated using Chilean zeolite as<br />microbial support. The results were compared to a conventional UASB reactor used as control. The<br />volume of each reactor was 2 L. The reactors operated with synthetic wastewater under the same<br />operating conditions (with superficial velocities, vs, of up to 1 m/h) in the first part of the experiment.<br />Later, during the second part of the experiment, only the modified UASB was used, with vs of up to<br />5.5 m/h. In the first part of the experiment, a higher velocity of denitrification in the reactor with<br />zeolite was obtained. Nitrogen removal at the end of this experimental set for both reactors, with a vs<br />lower than 1 m/h, was 87%. In the second stage, the modified UASB reactor operated at vs of<br />between 1.5 and 5.5 m/h. Here, it was observed that the removal of nitrite increased significantly.<br />Specifically, at vs values of 2.5, 4.0 and 5.5 m/h, a value of the nitrogen loading rate (NLR) of 1.22 kg<br />N-NO2 -/m3/d was kept constant, achieving nitrogen removal efficiencies of 50%, 65% and 95.5%<br />respectively. This last value proves how highly effective the modified UASB reactor is when operating with vs as high as 5.5 m/h. https://ijer.ut.ac.ir/article_582_46922a0880a8f11f8f69cbb52b1396be.pdf