a biofilm sequencing batch reactor with a volume of 1.42 m3, nylon nets providing a 4,140 m2/m3 support area for biofilms and an automated operation with 8 hour cycles was studied. the duration of the experiment was 135 days. removal efficiencies e≥ 80% were obtained for carbonaceous matter, producing an effluent with 31±26.8 mg/l of filtered cod, 7±3.6 mg/l of bod5 and 12±3.2 mg/l of toc. the ...

background : the sequencing batch reactor (sbr) is one of the most widely used systems in sewage treatment because of the simplicity of the process, flexibility of operation in the removal of nutrients, and the ability to be used in different scales. the aim of this study was to evaluate the efficiency of the sbr in the removal of organic matter (nitrogen and phosphorus) from synthetic wastewat...

In the present study the influence of hydraulic retention time (HRT) in SBR and sludge age (SRT) on the effectiveness of nitrogen removal from leachate was investigated. Two series were performed. In each series, experiments were carried out in four SBR operated in parallel at HRT 12, 6, 3 and 2d, respectively. Each series differed in sludge age. In series 1, SRT decreased from 51 to 17d with s...

A comprehensive and global sensitivity analysis was conducted under a range of operating conditions. The relative importance of mass transfer resistance versus kinetic parameters was studied and found to depend on the operating regime as follows: Operating under the optimal loading ratio of 1.90(gO(2)/m(3)/d)/(gN/m(3)/d), the system was influenced by mass transfer (10% impact on nitrogen remova...

Human alteration of the nitrogen cycle has led to increased riverine nitrogen loads, contributing to the eutrophication of lakes, streams, estuaries, and near‐coastal oceans. These riverine nitrogen loads are usually less than the total nitrogen inputs to the system, indicating nitrogen removal during transport through the drainage network. A two‐year monitoring study quantified the ammonium, n...

Most of domestic wastewater is either untreated or only primarily settled by septic tanks in Taiwan. Manure produced by concentrated swine operations is also one of the primary pollution sources of watercourses. Recently, constructed wetlands have received tremendous interests as one of the contemporary alternatives employing to enhance the water quality regarding nitrogen nutrients due to the ...

Treated wastewater discharged from more than 400 onsite wastewater treatment systems (OWTS) near the Civic Center area of Malibu, California, 40 km west of downtown Los Angeles, composes 28% of the recharge to a 3.4 km(2) alluvial aquifer. On the basis of δ(18) O and δD data, the fraction of wastewater in some samples was >70%. Ammonium and nitrate concentrations in water from 15 water-table we...

The effective management of high ammonium containing wastewater is important for the sustainable development of the wastewater industry. A pre-denitrification and post-nitrification two-sludge system was proposed to treat high ammonium containing wastewater with low carbon-to-nitrogen (C/N) ratios. In the system, pre-denitrification was adopted to use organic carbon in raw wastewater efficientl...

Constructed and natural wetlands are being used extensively to treat different types of wastewater including the domestic one. Considerable removal efficiency has been achieved for a variety of pollutants like BOD, nitrogen and phosphorous in the wetlands. Wetland treatment appears to be the best choice for treatment or pre-treatment of wastewater because of the low maintenance cost and simplic...