Showing papers on "Hydraulic retention time published in 2018"
TL;DR: This study constructed a 1000 L modularized MFC system, the largest volume so far, to treat practical municipal wastewater, which stably met the level A of the first class in discharge standard of pollutants for MWTP of China.
232 citations
TL;DR: The upflow anaerobic sludge blanket (UASB) reactor has been recognized as an important wastewater treatment technology among an-aerobic treatment methods as discussed by the authors, and the authors of this study performed literature review on the treatment of domestic sewage using the UASB reactor as the core component and identifying future areas of research.
Abstract: The upflow anaerobic sludge blanket (UASB) reactor has been recognized as an important wastewater treatment technology among anaerobic treatment methods. The objective of this study was to perform literature review on the treatment of domestic sewage using the UASB reactor as the core component and identifying future areas of research. The merits of anaerobic and aerobic bioreactors are highlighted and other sewage treatment technologies are compared with UASB on the basis of performance, resource recovery potential, and cost. The comparison supports UASB as a suitable option on the basis of performance, green energy generation, minimal space requirement, and low capital, operation, and maintenance costs. The main process parameters such as temperature, hydraulic retention time (HRT), organic loading rate (OLR), pH, granulation, and mixing and their effects on the performance of UASB reactor and hydrogen production are presented for achieving optimal results. Feasible posttreatment steps are also identified for effective discharge and/or reuse of treated water.
116 citations
TL;DR: A novel design of microbial fuel cells fuelled with undiluted urine was demonstrated to be an efficient power source for decentralised areas, but had only been tested under controlled laboratory conditions, so a field-trial was carried out to assess its feasibility for practical implementation.
98 citations
TL;DR: The succession of AD-related microbiome hosting diverse members of the phylum Actinobacteria, Bacteroidetes, Euryarchaeota, and Firmicutes, which were affected by organic loading rate (OLR) and hydraulic retention time (HRT), suggests the further subdivision of functional components.
93 citations
TL;DR: In this article, the optimization of biogas production from sewage sludge (SS) was attempted by co-digesting with a dried mixture of food waste, cheese whey and olive mill wastewater (FCO).
92 citations
TL;DR: Stable, long-term production of n-caproate from acid whey is shown by shaping the reactor microbiome in a UASB bioreactor by demonstrating the inherent heterogeneity of microbial subpopulations in terms of microbial activity at different points of fermentation.
91 citations
TL;DR: In this paper, the authors investigated the removal of sulfadiazine (SDZ) and the potential risks of antibiotic resistance gene (ARG) accumulation in up-flow microbial fuel cell coupled constructed wetlands (UCW-MFCs).
91 citations
TL;DR: In this article, the state of the art of recent research on denitrification through H2-based membrane biofilm reactor (MBfR) is reviewed, including theoretical fundamentals, key influencing factors, possible problems and applications.
90 citations
TL;DR: In this article, the influence of metal and metal-oxide nanoparticles (NPs) on biogas production from green microalgae Enteromorpha was evaluated, and the results showed that NPs has moderate positive influence in biOGas production until 60h of retention time but significantly improve afterward.
89 citations
TL;DR: In this article, the authors proposed the use of DO, pH and ORP profiles to reveal the evolution of wastewater treatment in a photo-sequencing batch reactor (PSBR) treating real municipal wastewater with a mixed consortium of microalgae and bacteria.
87 citations
TL;DR: A high diversity and rapid variations in the structure of microalgae populations are revealed during piggery wastewater treatment in four open photobioreactors, with Chlorella sp.
TL;DR: The mathematical models were developed and well calibrated for simulating the AnMBR performance in the biodegradation of COD and antibiotics and the obtained total COD removal efficiency was as high as 94.0% and accompanied with VFA accumulation.
TL;DR: In this paper, a post-endogenous denitrification and phosphorus removal (post-EDPR) system was developed by enriching denitrifying glycogen accumulating organisms (DGAOs) and phosphorus accumulating organisms(PAOs) to treat low carbon/nitrogen (C/N) wastewater.
TL;DR: In this paper, a staged anaerobic fluidized bed ceramic membrane bioreactor (SAF-CMBR) was used for low-strength wastewater treatment, where Granular activated carbon (GAC) particles were fluidized by bulk recirculation through the membrane reactor to control membrane fouling.
TL;DR: Two-stage anoxic/oxic combined membrane bioreactor process was used to treat leachate generated from Shenyang Laohuchong landfill, and the effect of hydraulic retention time (HRT) was studied.
TL;DR: In this paper, the feasibility of food waste treatment using a third generation anaerobic reactor was analyzed and the results showed that more than 90% of the organic matter in food waste could be recovered as bioenergy with an OLR greater than 20 kg COD/m3 d.
Abstract: Food waste (FW), which contains a large amount of easily biodegradable organic matter, has great potential for methane production using anaerobic digestion (AD). However, the bioenergy conversion efficiency in this method is not ideal because FW has a long hydraulic retention time (HRT) of > 20 days, low organic loading rate (OLR) of 1–6 g VS /L.d and low bioenergy conversion rate 40–70%. To improve the efficiency of bioenergy conversion, pretreatment technologies, co-digestion with other organic wastes and the effect of reactor types are reviewed and discussed. Enzymatic pretreatment and co-digestion of FW with landfill leachate are preferable for hydrolysis of organic solids, enhancement of methane production and stability improvement of the AD system. Based on the discussion and our preliminary experiment results, the feasibility of FW treatment using a third generation anaerobic reactor is proposed and analyzed. If the proposed concept can be applied practically in the future, more than 90% of the organic matter in FW could be recovered as bioenergy with an OLR greater than 20 kg COD/m3 d.
TL;DR: In this paper, a single chamber membraneless air cathode microbial fuel cell coupled constructed wetland (MFC-CW) was constructed to treat nitrobenzene-containing wastewater and generate electricity simultaneously.
TL;DR: The MEC system obtained almost complete nitrate removal under all conditions, while nitrite accumulation was recorded at nitrate loads higher than 100mgNO3-L-1, and the anolyte configuration in closed loop allowed the process to use less clean water, while guaranteeing identical performances as in other conventional configurations.
TL;DR: In this article, the effect of hydraulic retention time (HRT) and organic loading rate (OLR) on the volatile fatty acids (VFAs) production from cheese whey and sludge, and to find the relation between total VFA accumulation at different HRT and OLR and the corresponding bacterial community.
TL;DR: This study sets the record on the highest n-caproate concentration observed in a chain elongation process to date and demonstrates that such high concentrations can be obtained from AFW under practical circumstances in a continuous process.
Abstract: Introduction: Medium chain fatty acids (MCFAs), such as n-caproate, are potential valuable platform chemicals. MCFAs can be produced from low-grade organic residues by anaerobic reactor microbiomes through two subsequent biological processes: hydrolysis combined with acidogenesis and chain elongation. Continuous chain elongation with organic residues becomes effective when the targeted MCFA(s) are produced at high concentrations and rates, while excessive ethanol oxidation and base consumption are limited. The objective of this study was to develop an effective continuous chain elongation process with hydrolyzed and acidified food waste and additional ethanol. Results: We fed acidified food waste (AFW) and ethanol to an anaerobic reactor while operating the reactor at long (4 d) and at short (1 d) hydraulic retention time (HRT). At long HRT, n-caproate was continuously produced (5.5 g/L/d) at an average concentration of 23.4 g/L. The highest n-caproate concentration was 25.7 g/L which is the highest reported n-caproate concentration in a chain elongation process to date. Compared to short HRT (7.1 g/L n-caproate at 5.6 g/L/d), long HRT resulted in 6.2 times less excessive ethanol oxidation. This led to a two times lower ethanol consumption and a two times lower base consumption per produced MCFA at long HRT compared to short HRT. Conclusions: Chain elongation from AFW and ethanol is more effective at long HRT than at short HRT not only because it results in a higher concentration of MCFAs but also because it leads to a more efficient use of ethanol and base. The HRT did not influence the n-caproate production rate. The obtained n-caproate concentration is more than twice as high as the maximum solubility of n-caproic acid in water which is beneficial for its separation from the fermentation broth. This study does not only set the record on the highest n-caproate concentration observed in a chain elongation process to date, it notably demonstrates that such high concentrations can be obtained from AFW under practical circumstances in a continuous process.
TL;DR: In this article, the effect of hydraulic retention time (HRT) on algal biomass production and nutrient removal was investigated in membrane photobioreactors (MPBRs) in which Chlorella vulgaris was cultured with secondary effluent.
TL;DR: The excessSludge was identified as the major emission source of PAHs in coke wastewater during the hybrid A1/A2/O process, and might pose an environmental risk if the excess sludge was not properly treated and disposed.
TL;DR: In this article, the performance of five full scale biogas plants treating chicken manure (CM), pig manure (PM), a mixture of chicken and pig manure, dairy manure (DM), and maize straw (MS) were investigated.
TL;DR: This study evaluated micropollutants removal and membrane fouling behaviour of a hybrid moving bed biofilm reactor-membrane bioreactor (MBBR-MBR) system at four different hydraulic retention times (HRTs) and revealed that HRT of 18h was the optimal condition regarding the removal of most selected micropolutants.
TL;DR: Two-stage continuous H2 and CH4 production in a two-stage process to increase energy recovery from agave bagasse enzymatic-hydrolysate significantly increased energy conversion efficiency compared to one-stage hydrogen production and volumetric methane production rate.
TL;DR: In this article, a membrane bioreactor and two hybrid moving bed biofilm reactor-membrane (MBBR-MBR) systems were operated for the treatment of wastewater with tidal salinity fluctuations under hydraulic retention times of 6, 9.5 and 12 h, and operational solids concentrations of around 2500 and 3500
TL;DR: The results suggest that granules with advantages such as elevated biomass retention and greater biomass concentration could be effective for the removal of this class of antibiotics.
TL;DR: This work established continuous H2 and CH4 production from canteen food waste in a two-stage system by optimizing process parameters and microbial characterization indicated that methane formation was through syntrophic acetate oxidation combined with hydrogenotrophic methanogenesis pathway.
TL;DR: Low throughput 16S rRNA sequencing data revealed that microbial communities were just slightly affected by changes in digester operating conditions, suggesting that varying the PM/FW feedstock composition at the mixing ratios studied should not have major consequences for digestate disposal.
TL;DR: Effluent quality analysis showed the effluent soluble microbial products (SMP) were dominated by proteins compared to carbohydrates, and specific ultraviolet absorbance (SUVA) analysis revealed effluent from both reactors had low aromaticity with SUVA < 1 (L·mg-1·m-1) except for the first ten days.