Showing papers on "Hydraulic retention time published in 2009"
TL;DR: A single-chamber microbial fuel cell with an air cathode with a small volume biosensor was tested as a biosensor and the performance was analysed in terms of its measurement range, its response time, its reproducibility and its operational stability.
252 citations
TL;DR: The chemical oxygen demand (COD) elimination reached 95.3% demonstrating that cheese whey could be efficiently used for hydrogen and methane production, in a two-stage process.
225 citations
TL;DR: In this paper, the effects of varying hydraulic retention time (HRT: 1, 2 and 3.5 days) and especially high organic load rates (OLR: 21, 35 and 47 ǫg chemical oxygen demand (COD)/l/day) on biohydrogen production in a continuous stirred tank reactor were investigated.
191 citations
TL;DR: A lab-scale evaluation of a novel and integrated biological nitrogen removal process: the sulfate reduction, autotrophic denitrification and nitrification integrated (SANI) process that was recently proposed for saline sewage treatment found that accumulation of elementary sulfur and loss of hydrogen sulfide in the system were negligible.
186 citations
TL;DR: A real-time control strategy for A(2)N-SBR can be undertaken based on some characteristic points of pH, redox potential (ORP) and dissolved oxygen (DO) profiles in order to obtain the optimum hydraulic retention time (HRT) and improve the operating reliability.
144 citations
TL;DR: The biodegradation potential of an innovative enclosed tubular biofilm photobioreactor inoculated with a Chlorella sorokiniana strain and an acclimated activated sludge consortium was evaluated under continuous illumination and increasing pretreated swine slurry loading rates.
Abstract: The biodegradation potential of an innovative enclosed tubular biofilm photobioreactor inoculated with a Chlorella sorokiniana strain and an acclimated activated sludge consortium was evaluated under continuous illumi- nation and increasing pretreated (centrifuged) swine slurry loading rates. This photobioreactor configuration provided simultaneous and efficient carbon, nitrogen, and phospho- rous treatment in a single-stage process at sustained nitrogen and phosphorous removals efficiencies ranging from 94% to 100% and 70-90%, respectively. Maximum total organic carbon (TOC), NH4 + , and PO4 3− removal rates of 80±5 g C mr −3 day −1 ,8 9±5 gNm r −3 day −1 , and 13±3 g Pm r −3 day −1 , respectively, were recorded at the highest swine slurry loadings (TOC of 1,247±62 mg L −1 ,N -NH4 + of 656±37 mg L −1 ,P -PO4 3+ of 117±19 mg L −1 , and 7 days of hydraulic retention time). The unusual substrates diffusional pathways established within the phototrophic biofilm (photosynthetic O2 and TOC/NH4 + diffusing from opposite sides of the biofilm) allowed both the occurrence of a simultaneous denitrification/nitrification process at the highest swine slurry loading rate and the protection of microalgae from any potential inhibitory effect mediated by the combination of high pH and high NH3 concentrations. In addition, this biofilm-based photobioreactor supported efficient biomass retention (>92% of the biomass generated during the pretreated swine slurry biodegradation).
140 citations
TL;DR: A combined two-step process of heterotrophic Denitrification in a fluidized reactor and sulfur autotrophic denitrification processes (CHSAD) was developed for the removal of nitrate in drinking water and the nitrate removal was nearly 100% and there was no accumulated nitrite or residual methanol in the effluent.
129 citations
TL;DR: Three Microbial Fuel Cells were fluidically connected in series and the system when configured into a loop was able to remove 79% of COD and 82% of BOD after 4 days, demonstrating the MFC system's ability to treat leachate with the added benefit of generating energy.
127 citations
TL;DR: The filterability results showed that the anaerobic effluent was characterised by a slightly better filterability efficiency than the aerobic effluent, and increasing FVW proportions in the feedstock significantly improved the biogas production yield.
119 citations
TL;DR: The influence of the hydraulic retention time (HRT) and organic loading rate (OLR) on the performance of the hydrolytic-acidogenic step of a two-stage anaerobic digestion process of sunflower oil cake (SuOC) were assessed.
119 citations
TL;DR: The simulated results showed a good fit for pH, methane and carbon dioxide percentages, biogas volume, chemical oxygen demand, total volatile fatty acids, inorganic nitrogen and inorganic carbon.
TL;DR: In this article, the optimum values of hydraulic retention time (HRT) and organic loading rate (OLR) of an anaerobic sequencing batch reactor (ASBR) for bio-hydrogen production from palm oil mill effluent (POME) under thermophilic conditions (60°C) were investigated in order to achieve the maximum process stability.
TL;DR: A field test was conducted on a hydrolysis acidification/bio-contact oxidation system (HA/BCO) to treat oilfield-produced water with high salinity as discussed by the authors.
TL;DR: The findings of this investigation suggest that MSBR can be a robust and promising process for effectively treating wastewaters containing inhibitor or recalcitrant compounds in industrial settings.
TL;DR: The use of an integrated treatment scheme consisting of wet hydrogen peroxide catalytic oxidation followed by two-stage upflow anaerobic sludge blanket (UASB) reactor (10l each) for the treatment of olive mill wastewater indicated a good quality final effluent.
TL;DR: Observations from scanning electron micrographs (SEM) suggest that distinct phase separation takes place in an ABR, indicating excellent reactor stability at PSS in terms of effluent characteristics.
TL;DR: In this article, two microbial cultures with high decolorization efficiencies of reactive dyes were obtained and were proved to be dominant with fungi consortium in which 21 fungal strains were isolated and 8 of them showed significant decolorisation effect to reactive red M-3BE.
TL;DR: The reductive transformation of the anthraquinone derivatives in the ME reactor improved the biodegradability of the wastewater, and rendered the decolorization.
TL;DR: In this article, two continuously stirred tank (CSTRs) were used under mesophilic conditions (35°C) in order to enhance acidogenesis and methanogenesis, and the overall process was designed with a hydraulic retention time (HRT) of 19 days.
TL;DR: Only at the highest temperature tested it was possible to increase the maximum assimilative 4-CP concentration by the biological sludge up to 2100 mg/L, and a significant reduction of the ecotoxicity of the effluents was observed.
TL;DR: The configuration of the MABR, its start-up, effect of variation of hydraulic retention time (HRT) on treatment efficiency, and performance evaluation of theMABR while treating the municipal wastewater are presented.
TL;DR: In this article, the effect of three operational parameters (pH, hydraulic retention time (HRT) and growing temperature) on a semi-continuous bioreactor treating Tequila's vinasses by anaerobic digestion (AD) was measured through four response variables: total reducing sugars consumption, VFA's, hydrogen and methane production.
Abstract: The objective of this work was to study the effect of three operational parameters (pH, hydraulic retention time (HRT) and growing temperature) on a semi-continuous bioreactor treating Tequila's vinasses by anaerobic digestion (AD). The response was measured through four response variables: total reducing sugars (TRS) consumption, VFA's, hydrogen and methane production. Trials were done according to a factorial design. The experimental results were studied through a multiple response optimization (MRO) analysis to find single and multiple optimums for the above-mentioned variables. Mathematical models that can describe the effect of the operational parameters on each response variable were found. In this study it is shown that hydrogen production is favored at thermophilic growth (55 °C), operating the reactor at a slight acidic pH range and at the higher HRT in the boundaries of the experimental region.
TL;DR: In this paper, a continuous stirred tank (CSTR) was operated with pig slurry under hyper-thermophilic (70 � C) temperature for hydrogen production, and the results indicate that this system is a promising one for bio-hydrogen production from pig sluria.
Abstract: A continuous stirred tank reactor (CSTR) (750 cm 3 working volume) was operated with pig slurry under hyper-thermophilic (70 � C) temperature for hydrogen production. The hydraulic retention time (HRT) was 24 h and the organic loading rate was 24.9 g d � 1 of volatile solid (VS). The inoculum used in the hyper-thermophilic reactor was sludge obtained from a mesophilic methanogenic reactor. The continuous feeding with active biomass (inoculum) from the mesophilic methanogenic reactor was necessary in order to achieve hydrogen production. The hyper-thermophilic reactor started to produce hydrogen after a short adapted period of 4 days. During the steady state period the mean hydrogen yield was 3.65 cm 3 g � 1 of volatile solid added. The high operation temperature of the reactor enhanced the hydrolytic activity in pig slurry and increased the volatile fatty acids (VFA) production. The short HRT (24 h) and the hyper-thermophilic temperature applied in the reactor were enough to prevent methanogenesis. No pre-treatment methods or other control methods for preventing methanogenesis were necessary. Hyper-thermophilic hydrogen production was demonstrated for the first time in a CSTR system, fed with pig slurry, using mixed culture. The results indicate that this system is a promising one for biohydrogen production from pig slurry.
TL;DR: In this article, a free-water surface wetland covering an area of 2800 m2 was operated from March 2002 to June 2004 for agricultural runoff treatment in the Dianchi Valley in China.
TL;DR: Organic and nitrogen removal efficiencies in subsurface horizontal flow wetland system (HSF) with cattail (Typha augustifolia) treating young and partially stabilized solid waste leachate were investigated and high nitrogen in the stabilized leachates adversely affected the treatment performance and vegetation in the system.
TL;DR: In this article, a novel process has been developed at pilot scale for the treatment of olive mill wastewater (OMW), which combines electro-Fenton, anaerobic digestion and ultra-filtration.
Abstract: A novel process has been developed at pilot scale for the treatment of olive mill wastewater (OMW), which combines electro-Fenton, anaerobic digestion and ultrafiltration. Application of electro-Fenton procedure in semi-continuous mode permitted high removal efficiencies of chemical oxygen demand (COD) (50%) and monophenolic compounds (95%). This pre-treatment was found to enhance the anaerobic activity of an up-flow anaerobic filter (300 l) significantly. In the bioreactor, COD removal efficiency of 75% was reached at a hydraulic retention time of 4.5 d and an organic loading rate of 10 g COD l −1 d −1 . The use of ultrafiltration technology as a post-treatment completely detoxified the anaerobic effluent and removed its high molecular mass polyphenols. An economic calculation of this treatment process revealed that a surplus of energy of 73.5 kWh could be recovered after the treatment of 1 m 3 .
TL;DR: Anaerobic co-digestion of fruit and vegetable waste (FVW) and abattoir wastewater (AW) was investigated using anaerobic sequencing batch reactors (ASBRs) and the effects of hydraulic retention time (HRT) and temperature variations on digesters performances were examined.
Abstract: Anaerobic co-digestion of fruit and vegetable waste (FVW) and abattoir wastewater (AW) was investigated using anaerobic sequencing batch reactors (ASBRs). The effects of hydraulic retention time (HRT) and temperature variations on digesters performances were examined. At both 20 and 10 days biogas production for co-digestion was greater thanks to the improved balance of nutrients. The high specific gas productions for the different digestion processes were 0.56, 0.61 and 0.85 l g(-1) total volatile solids (TVS) removal for digesters treating AW, FVW and AW + FVW, respectively. At an HRT of 20 days, biogas production rates from thermophilic digesters were higher on average than from mesophilic AW, FVW and AW + FVW digestion by 28.5, 44.5 and 25%, respectively. However, at 10 days of HRT results showed a decrease of biogas production rate for AW and AW + FVW digestion processes due to the high amount of free ammonia at high organic loading rate (OLR).
TL;DR: In this paper, the optimal design of different free-water-surface constructed wetlands (FWS CWs) according to hydraulic efficiency index (λ) is provided, which is mainly determined by the position and distribution of the hydraulic retention time (HRT) curve of a wetland.
TL;DR: Investigation of the effect of solids retention time (SRT) and biomass concentration on generation of volatile fatty acids (VFA) from the non-methanogenic fermentation of waste activated sludge (WAS) originating from an enhanced biological phosphorus removal process found that VFA yields increased with SRT.
TL;DR: The results of denaturing gel gradient electrophoresis (DGGE), 16S rDNA gene sequence analysis, and hierarchical cluster analysis showed that the microbial community structures in MBfR were of low diversity, simple and stable at mature stages; and the beta-Proteobacteria probably play an important role in autohydrogenotrophic denitrification.