the effect of hydraulic retention time in a range from 1.0-5.5 days was evaluated in a laboratoryscaleanaerobic fixed bed reactor packed with a hybrid material composed of tire rubber and zeolite. underthese conditions, cod removal efficiencies varied from 28.3% to 82.1%, respectively. over the more than 6months of operation, no clogging was observed. the results obtained demonstrated that this...

An anaerobic digestion of palm oil mill effluent (POME) for production of biogas was carried out at pilot scale under thermophilic condition. The objective of this research is to maintain short hydraulic retention time (HRT) and high degradation of the POME to biogas by applying recycle sludge. Fresh POME from PTPN IV without further treatment was used as feed. The fermentation process occurred...

A steady state model for anaerobic digestion of sewage sludge is developed that comprises three sequential parts – a kinetic part from which the % COD removal and methane production are determined for a given retention time; a stoichiometry part from which the gas composition (or partial pressure of CO2), ammonia released and alkalinity generated are calculated from the %COD removal; and a carb...

Co-digestion of dairy manure with off-farmwaste has become a common practice on US farms, however, little data at a commercial-scale is present within the literature. In response, a mesophilic, mixed plug-flow reactor co-digesting 16.36% v/v food processing substrates with dairy manure, was monitored for its performance and substrate effects. Co-digestion, as compared to substrate or manure-onl...

The modern closed digesters are becoming more popular for treating palm oil mill effluent (POME) and are currently being installed nationwide in Malaysia to replace the conventional open lagoons and tanks treatment system. This paper describes an accelerated start-up of the 500 m semi-commercial anaerobic digester 3 treating POME and methane gas recovery for clean development mechanism (CDM) pr...

Gas-mixing is commonly applied in anaerobic digesters, yet the resulting flow and hydraulic mixing are difficult to evaluate because of limited full-scale experimental data uncertainties integrating sludge rheological data. This study used computational fluid dynamics (CFD) assess impact treated rheology on characterisation a biogas-mixed digester. The CFD model, which was firstly validated usi...

BACKGROUND Microalgae are a promising feedstock for biofuel and bioenergy production due to their high photosynthetic efficiencies, high growth rates and no need for external organic carbon supply. In this study, utilization of Chlorella vulgaris (a fresh water microalga) and Dunaliella tertiolecta (a marine microalga) biomass was tested as a feedstock for anaerobic H2 and CH4 production. RES...

Lengthy adaptation periods in laboratory studies evaluating the potential for contaminant biodegradation in natural or engineered environments may indicate that the native microbial communities are not metabolizing the contaminants in situ. In this study, we characterized the adaptation period preceding the biodegradation of 3-chlorobenzoate in anaerobic communities derived from lake sediment a...