Using dark fermentation, hydrogen can be generated from renewable organics including waste materials. Key to successful application of anaerobic fermentation is to uncouple liquid and biomass retention times in reactor system. This paper reviews reactor configurations (fixed-bed, fluidized-bed, upflow anaerobic sludge blanket and continuous stirred tank reactors) and operating processes (batch,...

Two laboratory-scale sequencing batch reactors were used to study biological treatment of carbon and nitrogen in a new combined anaerobic-aerobic system. Piggery wastewater was used as a model effluent. The anaerobic reactor, fed with raw wastewater and nitrite/nitrate recycling from the aerobic reactor, carried out denitrification and anaerobic digestion of organic carbon. In the aerobic react...

The removal of biological nitrogen from a synthetic wastewater with different ammonium nitrogen concentrations (50 and 100 mgN-NH4/L) by a nitrification and denitrification process using a sequencing batch biofilm reactor (SBBR) with liquid-phase circulation was studied. The system with a total working volume of 4.6 L (3.7 L in the reactor and 0.9 L in the reservoir) treated 2.1 L of synthetic ...

AIMS The bacterial diversity in a sequencing batch biofilm reactor (SBBR) treating landfill leachate was studied to explain the mechanism of nitrogen removal. METHODS AND RESULTS The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH(4) (+)-N higher than 97% and that of chemical oxygen demand (determin...

The selection of optimum high strength wastewater treatment process is complicated. Be familiar with wastewater treatment methods is not enough to design a plant. In this research, five alternative wastewater treatment methods (upflow anaerobic sludge blanket (UASB) + membrane bioreactor (MBR), UASB + Extended aeration (EA), Anaerobic baffled reactor (ABR), anaerobic lagoon (ANL) + aerated lago...

The objective of this paper is simultaneous of aerobic and anaerobic process for phosphorus removal from a dairy wastewater. The system consists of a granular sequencing batch reactor (SBR) working under alternating aerobic/anaerobic conditions. In order to analyze the process, four significant variables viz. MLSS, COD/N ratio, aeration time and cycling time and four dependent parameters as the...

Implementation of partial nitritation anammox (PNA) in the mainstream (municipal wastewater treatment) is still under investigation. Microbial community structure and reactor type can influence the performance of PNA reactor; yet, little is known about the role of the community composition of the inoculum and the reactor configuration under mainstream conditions. Therefore, this study investiga...

This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densi...