Two multistaged anaerobic digestion systems, a four-stage thermophilic anaerobic digestion (4TAD), all at 55°C, and a four-stage anaerobic digestion with a tapered temperature configuration (4ADT) at 55, 49, 43, and 37°C, respectively, were studied to evaluate their solids, volatile organic sulfur compounds, and indicator organism (E. coli and fecal coliform) reduction potentials. The 4TAD syst...

This study aims to investigate thermophilic methanogens in turf used as an inoculum. Results showed that Methanoculleus sp. regarded as hydrogenotrophic and Methanosarcina sp. regarded as acetoclastic methanogens were present in turf tested. However, active acetoclastic methanogens were present in turf soil only. The current study showed that thermophilic methanogens were present in various tur...

In this study, we investigated by running continuous stirred tank reactor the effects of different thermophilic temperatures (55, 60, 65, 70, 75 and 80C) for different hydraulic retention times (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 days, respectively) on the pretreatment of sewage sludge. We found that hydrolysis was mainly determined by temperature instead of hydraulic retention time, i.e. the high...

OBJECTIVE To verify the existence of a relationship between presence of off-flavor and microorganism load in quality control rejected samples of expressed human milk from a donor milk bank. METHODS A total of 30 samples of expressed human milk with off-flavor were tested for the occurrence of the following microorganisms: aerobic mesophilic, psycrotrophic, proteolytic, psycrotrophic proteolyt...

In this study, a short pre-aeration step was investigated as pre-treatment for thermophilic anaerobic digestion of the organic fraction of municipal solid waste (OFMSW). It was found that pre-aeration of 48 h generated enough biological heat to increase the temperature of bulk OFMSW to 60 degrees C. This was sufficient self-heating of the bulk OFMSW for the start-up of thermophilic anaerobic di...

The first step of anaerobic digestion, the hydrolysis, is regarded as the rate-limiting step in the degradation of complex organic compounds, such as waste-activated sludge (WAS). The aim of lab-scale experiments was to pre-hydrolyze the sludge by means of low intensive alkaline sludge conditioning before applying hydrodynamic disintegration, as the pre-treatment procedure. Application of both ...

a thermophilic anaerobic contact reactor for the treatment of potato-processing wastewaterswas designed as a continuous-flow, completely-mixed homogeneous system. the reactor was operated at ten different organic loading rates ranging from 0.84 g cod/l·d to 7.00 g cod/l·d for a duration of approximately 250 days. the fundamental way to maintain optimum operating conditions of anaerobic digestio...