sulfur utilizing autotrophic denitrification synthetic wastewater in up flow packed --bed reactor was evaluated under different concentrations of alkalinity and organic matter. the reactor was filled with granular elemental sulfur particles with diameters of 2.8-5.6 mm and porosity of 40%. the initial culture was prepared from sludge of shahrak ghods wastewater treatment plant. first, the stoic...

denitrification of high- nitrate high- salinity wastewater is difficult due to plasmolysis and inactivation of denitrifiers at high salinity conditions. in this study, the effects of salinity and empty bed contact time (ebct) on simultaneous heterotrophic and sulfur based autotrophic denitrification of synthetic wastewater were evaluated in an up flow packed bed reactor .the reactor was filled ...

Introduction: The biological denitrification process is an interesting cost-effective technique to remove nitrate from water supplies. Acetic acid can be used as a carbon source in this process, but its consumption rate is a critical issue and, in some cases, it is quite different from stoichiometric constants. The current study aimed to investigate the nitrate removal in an up-flow packed bed ...

Sulfur-utilizing autotrophic denitrification relies on an inorganic carbon source to reduce the nitrate by producing sulfuric acid as an end product and can be used for the treatment of wastewaters containing high levels of nitrates. In this study, sulfur-denitrifying bacteria were used in anoxic batch tests with sulfur as the electron donor and nitrate as the electron acceptor. Various medium ...

introduction:nitrate entrance to water bodies can cause eutrophication and decrease quality of them, furthermore it can effect on human health so concentration of nitrate must be at defined standard level. there are several methods for reduction or removal of nitrate in water such as ion exchange, reverse osmosis, electrodialysis and denitrification. microbial denitrification of nitrate in anox...

Sulfur-based autotrophic denitrification processes utilize autotrophic denitrifiers, such as Thiobacillus denitrificans and Thiomicrospira denitrificans, to reduce nitrate to nitrogen gas. Bench-scale experiments were conducted to evaluate the sulfur-based autotrophic denitrification process. This paper addresses three issues: (1) start-up and operation of a CSTR to provide an adequate seed sou...

Two combined bioelectrochemical and sulfur autotrophic denitrification (CBSAD) processes for the treatment of nitrate contaminated drinking water were studied in this article, the main difference between the two processes was whether the limestone was packed in the reactor. In these processes, the sulfur denitrification was carried out in the lower part (Sulfur Part) of the reactors while the b...

Hydrogenotrophic denitrification is promising for tertiary nitrogen removal from municipal wastewater. To reveal the influence of residual organics in municipal wastewater on hydrogenotrophic denitrifiers, we adopted high-throughput 16S rRNA gene amplicon sequencing to examine microbial communities in hydrogenotrophic denitrification enrichments. Using effluent from a municipal wastewater treat...

Sequential nitrification–autotrophic denitrification (SNaD) was carried out for ammonium removal in synthetic wastewater (SWW) using sulfur as an electron donor denitrification. Four reactors were operated batch mode, two with zeolite (1 mm size) used microbial support and without support, to assess the effect of addition SNaD. Aeration, anoxic, anaerobic cycles established, where 96% NH4+-N (o...

A significant amount of nitrous oxide (N(2)O), which is one of the serious greenhouse gases, is emitted from nitrification and denitrification of wastewater. Batch wastewater nitrifications with enriched nitrifiers were carried out under oxygen-limited condition with synthetic (without organic carbon) and real wastewater (with organic carbon) in order to find out the effect of ammonium concentr...