All bioreactor configurations are affected by mixing and transport phenomena and consequently the bioreactor’s hydraulics governs the reactor’s configurations as well as performance. For instance, to provide good conditions for substrate transport to, and from, the microbial aggregates, an even mixing pattern at the macro-level is desirable. However, the available data that either describe UASB...

A laboratory study using a combined upflow anaerobic sludge bed (UASB)-activated sludge (AS) reactor system was undertaken to explore the effect of recycle-to-influent ratio (R(e)=1, 2, and 3) on the activities of nitrifiers and denitrifiers. Suspended-solids pre-settled piggery wastewater was used as the substrate-feed wastewater. At the R(e) of 1-3, the combined reactor system achieved effici...

In the present investigation, an attempt was made to develop a treatment system for the management of atrazine bearing wastewater. The system consists of an upflow anaerobic sludge blanket ~UASB! reactor followed by an adsorption column using waste activated carbon as the adsorbent. The UASB reactor could remove more than 80% of organic matter and 40–50% of atrazine, irrespective of the concent...

Anaerobic digestion is an important alternative for domestic wastewater treatment, especially in warm climate regions. Two full-scale anaerobic schemes were investigated: septic tank combined with anaerobic filter (STANF) and conventional UASB reactors. Treated effluents from these systems were subjected to disinfection by chlorination. The operational performance of 56 full-scale plants (36 ST...

Performance of a rotating biological contactor (RBC) in treating municipal wastewater from primary sedimentation basin and anaerobically treated industrial effluent from an upflow anaerobic sludge blanket (UASB) reactor was investigated. The 280-L six-stage RBC pilot was operated at different organic loading rates and biodisc speeds. The overall removal efficiencies of soluble BOD decreased wit...

We herein analyzed the diversity of microbes involved in anaerobic sulfur oxidation in an upflow anaerobic sludge blanket (UASB) reactor used for treating municipal sewage under low-temperature conditions. Anaerobic sulfur oxidation occurred in the absence of oxygen, with nitrite and nitrate as electron acceptors; however, reactor performance parameters demonstrated that anaerobic conditions we...

This study was carried out to assess the efficiency of a combined system consisting of up-flow anaerobic sludge blanket (UASB) reactor and down-flow hanging sponge (DHS) system for color removal from reactive dyes wastewater. The UASB reactor and DHS system were operated at HRT of 6 and 2.0 h., respectively. The results obtained indicated that, the combined system was quite effective for remova...

Methane is produced by various methanogenic bacteria present in upflow anaerobic sludge blanket (UASB) bioreactors. Methane can be used to predict and improve UASB bioreactor efficiency. The methanogen population in the granules can be influenced by the composition of the substrate. The aim of this study was to fingerprint and identify the methanogens present in three different types of UASB gr...

The objective of this study is to evaluate the decolorization of Methylene Blue (MB) by an up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated under batch condition with total treatment volume of 3l and operation time of 24 h per batch. It was found that the color of MB disappeared within a few minutes after entering into the UASB reactor due to reduction by anaerobic...

Seghezzo, L. (2004), Anaerobic treatment of domestic wastewater in subtropical regions, Ph.D. thesis, Wageningen University, Wageningen, the Netherlands. In this thesis, the use of upflow anaerobic sludge bed (UASB) reactors for sewage treatment was studied in the city of Salta, northwestern Argentina. The climate in this region can be defined as subtropical with a dry season. Mean ambient temp...