Abstract
This work deals with the evaluation of the performance of discontinuous or sequential batch reactors (SBR) treating sewage, through a process of endogenous biological nitrate reduction. Different operational conditions were undertaken, and the behaviour under the effects of organic shock loading was considered. Three laboratory scale reactors were operated simultaneously, which were fed with artificial wastewater. The substratum was molasses and nitrate, respectively ,as carbon and nitrogen sources. The three reactors were operated during different aeration times (0, 15 and 30 minutes). Sudden changes (shock loading) in organic matter concentration were carried out along the experiment. Thus, influent load was increased threefold in relation to the original concentration. Results showed that SBR reactors responded quite properly to moderate shock loading. With regard to substratum degradation, Nitrate elimination achieved was around 80 %, while denitrification rate was about 0.87 mg g-1h-1.
