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David C Stuckey - One of the best experts on this subject based on the ideXlab platform.
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composition and biotransformational changes in soluble microbial products smps along an Anaerobic Baffled Reactor abr
2020Co-Authors: Yan Ni Annie Soh, David C Stuckey, Chinagarn Kunacheva, Richard D WebsterAbstract:Abstract This work examined the production and catabolism/biotransformation dynamics of SMPs down the length of an eight-compartment-Anaerobic Baffled Reactor (ABR) which physically separates the biological processes, in contrast to completely mixed Reactors which do not enable these dynamics to measured, and this is totally novel. SMPs were extracted and characterised by gas and liquid chromatography coupled mass spectrometry to determine their composition and production/catabolism. 60%–70% of the feed compounds decreased from the first to fourth compartment; the increase in SMPs after the fourth compartment suggested a mixture of degraded and biotransformed compounds, and microbial products. High concentrations of low MW alkanes and alkenes, and higher MW (up to 2000 Da) lipids and amino acid derivatives accumulate in the last compartment at pseudo-steady state, and past work identifying polysaccharides/peptides as major membrane biofoulants have excluded these lipids. In addition, lipids and changes detected during feed transients have not been noted before in previous work. Finally, feed step-increases also increased some amino acid derivatives used in cell-signalling. Interestingly, some natural products from plant and fungal extracts were also found in the fourth compartment, where methanogenesis was the dominant process.
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pilot scale study of an Anaerobic Baffled Reactor for the treatment of domestic wastewater
2002Co-Authors: P Dama, Joanne Bell, C A Buckley, K M Foxon, C J Brouckaert, T Huang, V Naidoo, David C StuckeyAbstract:Large proportions of South Africans live in areas with inadequate sanitation and a poor infrastructure for waterborne sanitation. Service providers are looking for alternative wastewater treatment options. The Anaerobic Baffled Reactor is being considered as a decentralised sanitation option in these areas. A 3,200 L Reactor was built and is currently being evaluated at a wastewater treatment works. The Reactor was built based on experiences gained from working with a laboratory Reactor (10 L) and predicted flow patterns observed on a computational fluid dynamics model. The design and construction of the Reactor will be discussed in this paper. The feed to the Reactor consists of screen degritted sewage and the flow to the Reactor is maintained by means of a programmable logic controller. The pilot-plant layout is discussed in this paper. Samples are analysed for chemical oxygen demand, pH, alkalinity, ammonia, phosphorus, solids and ash content. Reductions of between 70 and 80% are obtained for COD and the pH values for the effluent samples are within the discharge limits.
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microbial populations associated with treatment of an industrial dye effluent in an Anaerobic Baffled Reactor
2001Co-Authors: Jason J Plumb, Joanne Bell, David C StuckeyAbstract:Fluorescent in situ hybridization (FISH) using 16S and 23S rRNA-targeted probes together with construction of an archaeal 16S ribosomal DNA (rDNA) clone library was used to characterize the microbial populations of an Anaerobic Baffled Reactor successfully treating industrial dye waste. Wastewater produced during the manufacture of food dyes containing several different azo and other dye compounds was decolorized and degraded under sulfidogenic and methanogenic conditions. Use of molecular methods to describe microbial populations showed that a diverse group of Bacteria and Archaea was involved in this treatment process. FISH enumeration showed that members of the gamma subclass of the class Proteobacteria and bacteria in the Cytophaga-Flexibacter-Bacteroides phylum, together with sulfate-reducing bacteria, were prominent members of a mixed bacterial population. A combination of FISH probing and analysis of 98 archaeal 16S rDNA clone inserts revealed that together with the bacterial population, a methanogenic population dominated by Methanosaeta species and containing species of Methanobacterium and Methanospirillum and a relatively unstudied methanogen, Methanomethylovorans hollandica, contributed to successful Anaerobic treatment of the industrial waste. We suggest that sulfate reducers, or more accurately sulfidogenic bacteria, together with M. hollandica contribute considerably to the treatment process through metabolism of dye-associated sulfonate groups and subsequent conversion of sulfur compounds to carbon dioxide and methane.
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treatment and decolorization of dyes in an Anaerobic Baffled Reactor
2000Co-Authors: Joanne Bell, Jason J Plumb, C A Buckley, David C StuckeyAbstract:Synthetic organic colorants, the majority of which are recalcitrant in nature, are used universally in many different manufacturing processes. The dyes are released into the environment in industrial effluents and are highly visible even at low concentrations ( 20 g/L) to inhibitory (IC\D50\N = 0.2 mg/L). Batch biodegradability assays indicated that the dyes were not readily utilized by the Anaerobic microorganisms as a sole substrate. Decolorization of the dye tartrazine was investigated in a laboratory-scale Anaerobic Baffled Reactor at a concentration of 250 mg/L. Reduction in COD of 50–60% and color reduction of about 95% was achieved. Initially the tartrazine was not readily decolorized; however, decolorization improved with acclimation of the biomass. An industrial wastewater from a food dye manufacturer was fed to a second laboratory-scale Anaerobic Baffled Reactor at a concentration of 5% (volume-to-volume ratio) and then increased to 10%. Anaerobic degradation of the wastewater was efficient. Methanogenic activity was high; the organic content of the influent was reduced by about 70%, and color was reduced by almost 90%.
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treatment of dilute wastewater using an Anaerobic Baffled Reactor effect of low temperature
2000Co-Authors: Alette A M Langenhoff, David C StuckeyAbstract:Abstract The performance of an Anaerobic Baffled Reactor (ABR, 10 l and eight compartments) treating a dilute wastewater (500 mg COD/l) was studied. The Reactor was started with a hydraulic retention time (HRT) of 80 h at 35°C, and this was steadily reduced to 10 h eventually; all HRTs tested resulted in more than 80% COD removal. The temperature was then reduced to 20°C, which gave a removal efficiency of 70%, and finally to 10°C, which resulted in only 60% COD removal. Residence time distribution studies were carried out to monitor hydrodynamic flow characteristics and dead space after each decrease in temperature. Not much difference in mixing or dead space was observed under the different conditions tested. The average dead space was 25–30%, and the flow pattern within the Reactors showed an intermediate behaviour between plug-flow and ideally mixed. Finally, Anaerobic bioassays were used to evaluate the activity of the biomass. The biomass retained its initial specific acetogenic and methanogenic activity throughout the compartments of the Reactor, and hardly any selection for psychrophilic bacteria had taken place.
Dongsheng Shen - One of the best experts on this subject based on the ideXlab platform.
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effects of temperature and feed strength on a carrier Anaerobic Baffled Reactor treating dilute wastewater
2009Co-Authors: Huajun Feng, Qaisar Mahmood, Caidi Qiu, Chenran Fang, Dongsheng ShenAbstract:A carrier Anaerobic Baffled Reactor (CABR), containing hollow-sphere bamboo carriers, was used to examine theeffects of organic and temperature shock loads for a constant hydraulic retention time. The relationships among themacroscopic observables (pH, COD and SS), catabolic intermediates (VFA) and microcosm alternation (TTC–DHA)were studied. A slight fluctuation in pH was observed, ranging from 6.5 to 7.5 throughout the experiments. TheCABR had a COD removal efficiency of 91% with an effluent suspended solids (SS) of 15 mg L−1 at 28°C and a feedstrength of 600 mg L−1 chemical oxygen demand (COD). The Reactor could run steadily without souring due to thevolatile fatty acids (VFA) production (<150 mg L−1) and low VFA/alkalinity ratio (<0.23), although the effluent VFAconcentration increased with decreasing operational temperature. For a substrate low in nutrient, the microorganismsconverted the limited substrate into acetate to supply the essential nicotinamide adenine dinucleotide for cellularsynthesis. The tetrazolium chloride–dehydrogenase activity (TTC–DHA) of the attached biomass was higher thanthat of flock biomass at low feed concentration, whereas the result was the opposite at high feed concentration.Microorganisms with lower activity but higher shock resistance were dominant in the first chamber. Therefore, theCABR had high shock resistance and adaptability irrespective of temperature and feed strength.
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Anaerobic domestic wastewater treatment with bamboo carrier Anaerobic Baffled Reactor
2008Co-Authors: Huajun Feng, Qaisar Mahmood, Caidi Qiu, Chengran Fang, Dongsheng ShenAbstract:Abstract The carrier Anaerobic Baffled Reactor (CABR) was developed to treat sewage at 28 ± 1 °C. The performance during start-up, mechanism of pollutant removal and its potential to remove pathogenic microorganisms were investigated. The success of start-up was indicated by total chemical oxygen demand (TCOD), removal efficiency and the varying pH curve and/or alkalinity along the on site flow measurement. The TCOD removal efficiency decreased from 79% at a hydraulic retention time (HRT) of 48 h to 69% at 18 h due to washed-out biomass while soluble chemical oxygen demand (SCOD) removal efficiency was nearly constant. The total nitrogen to total phosphorus removal ratio that ranged from 3.5 to 6.5 in CABR was less than the average nitrogen to phosphorus ratio in living cells (5–7) due to partial phosphorus adsorption by biomass. About 63% of substrate was used for cell synthesis during the start-up phase, whereas only 20% substrate was consumed during the steady state operation. The Reactor had certain effect on the removal of pathogenic species, but it was necessary to adopt appropriate post-disinfection measures to guarantee the effluent safety. CABR is a suitable technology for decentralized domestic sewage treatment from rural areas of China.
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effects of operational factors on soluble microbial products in a carrier Anaerobic Baffled Reactor treating dilute wastewater
2008Co-Authors: Huajun Feng, Chengran Fang, H U Lifang, Dan Shan, H E Yonghua, Dongsheng ShenAbstract:Abstract The effects of feed strength, hydraulic residence time (HRT), and operational temperatures on soluble microbial product (SMP) production were investigated, to gain insights into the production mechanism. A carrier Anaerobic Baffled Reactor (CABR) treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9-18 h, and temperatures of 10–28°C. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature (28°C), SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10°C, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand (SCOD) ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.
Gefu Zhu - One of the best experts on this subject based on the ideXlab platform.
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deeper investigation on methane generation from synthetic wastewater containing oxytetracycline in a scale up acidic Anaerobic Baffled Reactor
2021Co-Authors: Ruming Wang, Xiaofang Pan, Xiaoyong Yang, Mingdian Zhou, Guanjing Cai, Yifeng Zhang, Gefu ZhuAbstract:Abstract Acidic Anaerobic digestion attracted much attention and interest due to its significant advantage in wastewater treatment. In the present study, methanogenic fermentation was successfully operated under acidic condition during treating wastewater containing oxytetracycline (OTC) in a scale up Anaerobic Baffled Reactor (ABR). After start-up process, the pH value in the first compartment was 4.60 with high activity of methanogenesis. After stabilization, different OTC loading of 1.0, 3.3 and 5.0 g/m3/d was added in the influent for OTC removal. The resulted showed that OTC addition had little impact on the methane generation with whole COD and OTC removal rate of 95% and 60%, respectively. The microbial analysis, OTC addition could significantly influence the bacteria and archaea communities. To be more specific, Methanosaeta showed the highest relative abundance and tolerance to OTC under acidic condition. The present work supplied deeper insights into methane generation from acidic condition during wastewater containing OTC treatment.
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process performance and microbial community functional structure in a thermophilic Anaerobic Baffled Reactor coupled with biocatalysed electrolysis
2020Co-Authors: Tao Wang, Xiaofang Pan, Gefu ZhuAbstract:In this study, the performances of a conventional Anaerobic Baffled Reactor (ABR) and an ABR combined with microbial electrolysis cells (MECs) for enhancing degradation of volatile fatty acids (VFA...
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simultaneous production of bio hydrogen and methane from soybean protein processing wastewater treatment using Anaerobic Baffled Reactor abr
2015Co-Authors: Gefu Zhu, Chaoxiang Liu, Xu Huang, Lin LiuAbstract:AbstractBio-hydrogen (H2) and methane (CH4) co-production from soybean protein processing wastewater (SPPW) was examined using a four-compartment Anaerobic Baffled Reactor (ABR) with the active Reactor volume (34 L) under continuous flow condition in this present study. At steady state, the ABR achieved H2 yields of 25.67 L/d, specific hydrogen production rate of Anaerobic activated sludge was 0.28 L/g MLVSS d, CH4 yields of 13.89 L/d, and chemical oxygen demand (COD) removal of 95% when operated at the organic loading rate of 1.9–2.6 kg COD/m3 d, hydraulic retention time of 48 h, and temperature of (35 ± 1) °C, respectively. The results showed that the niches of the bio-hydrogen-producing phase and the methane-producing phase in the ABR are different. A high alkalinity in the methanogenic compartment of the ABR was able to secure the pH neutral and methane generation. In general, the ABR proved to be a stable, reliable, and effective process for energy recovery and stabilization treatment of SPPW.
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hydrogen production with effluent from an Anaerobic Baffled Reactor abr using a single chamber microbial electrolysis cell mec
2013Co-Authors: Gefu Zhu, Ajay Kumar Jha, Xu Huang, Lin Liu, Ran Zou, Chaoxiang LiuAbstract:Abstract In the process of fermentative bio-hydrogen production, organic matter is degraded into volatile fatty acids and ethanol, and consequently thermodynamic constraints prevent the further spontaneous reactions. Moreover, the Anaerobic Baffled Reactor (ABR) with the advantage of phase separation could realize the acetic acid accumulation via acid-producing bacteria. The microbial electrolysis cell (MEC) could convert the acetic acid into hydrogen furthermore. Considering this, the ABR coupled with MEC has been operated to strengthen the hydrogen production. This study was designed regarding orthogonal experiments to operate the four-compartment ABR with a hydraulic retention time (HRT) = 24 h, influent COD ∼ 4600 mg/L, temperature = 35 ± 1 °C, and discovered the optimal parameters with pH = 7, C/N = 44, and 2-bromoethanesulfonate (BES) concentration = 20 mmol/L to achieve the high acetic acid accumulation of effluent. The single-chamber membranless MEC with carbon anode and Ni-catalyst stainless steel cathode (liquid volume = 85 mL) fed with the ABR effluent with applied voltage = 0.6 V and electric conductivity = 7.45 mS/cm, achieved 99.0 ± 0.3% total COD removal efficiency, 1.31 ± 0.04 m 3 H 2 /m 3 d hydrogen production, 2.78 ± 0.11 mLH 2 /mgCOD hydrogen yield and 138.63 ± 3.11% electrical energy efficiency. Therefore the ABR-MEC system could overcome the “fermentation barrier” to achieve higher hydrogen production and organic matter degradation.
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fermentative hydrogen production from soybean protein processing wastewater in an Anaerobic Baffled Reactor abr using Anaerobic mixed consortia
2012Co-Authors: Gefu Zhu, Chaoxiang LiuAbstract:Fermentative H(2) production from soybean protein processing wastewater (SPPW) was investigated in a four-compartment Anaerobic Baffled Reactor (ABR) using Anaerobic mixed cultures under continuous flow condition in the present study. After being inoculated with aerobic activated sludge and operated at the inoculants of 5.98 gVSS L(-1), COD of 5000 mg L(-1), HRT of 16 h and temperature of (35 ± 1) °C for 22 days, the ABR achieved stable ethanol-type fermentation. The specific hydrogen production rate of Anaerobic activated sludge was 165 LH(2)kg MLVSS(-1) day(-1), the substrate conversion rate was 600.83 LH(2)kg COD(-1)and the COD removal efficiency was 44.73% at the stable operation status. The ABR system exhibited a better stability and higher hydrogen yields than continuous stirring tank Reactor under the same operational condition. The experimental data documented the feasibility of substrate degradation along with molecular H(2) generation utilizing SPPW as primary carbon source in the ABR system.
Huajun Feng - One of the best experts on this subject based on the ideXlab platform.
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effects of temperature and feed strength on a carrier Anaerobic Baffled Reactor treating dilute wastewater
2009Co-Authors: Huajun Feng, Qaisar Mahmood, Caidi Qiu, Chenran Fang, Dongsheng ShenAbstract:A carrier Anaerobic Baffled Reactor (CABR), containing hollow-sphere bamboo carriers, was used to examine theeffects of organic and temperature shock loads for a constant hydraulic retention time. The relationships among themacroscopic observables (pH, COD and SS), catabolic intermediates (VFA) and microcosm alternation (TTC–DHA)were studied. A slight fluctuation in pH was observed, ranging from 6.5 to 7.5 throughout the experiments. TheCABR had a COD removal efficiency of 91% with an effluent suspended solids (SS) of 15 mg L−1 at 28°C and a feedstrength of 600 mg L−1 chemical oxygen demand (COD). The Reactor could run steadily without souring due to thevolatile fatty acids (VFA) production (<150 mg L−1) and low VFA/alkalinity ratio (<0.23), although the effluent VFAconcentration increased with decreasing operational temperature. For a substrate low in nutrient, the microorganismsconverted the limited substrate into acetate to supply the essential nicotinamide adenine dinucleotide for cellularsynthesis. The tetrazolium chloride–dehydrogenase activity (TTC–DHA) of the attached biomass was higher thanthat of flock biomass at low feed concentration, whereas the result was the opposite at high feed concentration.Microorganisms with lower activity but higher shock resistance were dominant in the first chamber. Therefore, theCABR had high shock resistance and adaptability irrespective of temperature and feed strength.
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Anaerobic domestic wastewater treatment with bamboo carrier Anaerobic Baffled Reactor
2008Co-Authors: Huajun Feng, Qaisar Mahmood, Caidi Qiu, Chengran Fang, Dongsheng ShenAbstract:Abstract The carrier Anaerobic Baffled Reactor (CABR) was developed to treat sewage at 28 ± 1 °C. The performance during start-up, mechanism of pollutant removal and its potential to remove pathogenic microorganisms were investigated. The success of start-up was indicated by total chemical oxygen demand (TCOD), removal efficiency and the varying pH curve and/or alkalinity along the on site flow measurement. The TCOD removal efficiency decreased from 79% at a hydraulic retention time (HRT) of 48 h to 69% at 18 h due to washed-out biomass while soluble chemical oxygen demand (SCOD) removal efficiency was nearly constant. The total nitrogen to total phosphorus removal ratio that ranged from 3.5 to 6.5 in CABR was less than the average nitrogen to phosphorus ratio in living cells (5–7) due to partial phosphorus adsorption by biomass. About 63% of substrate was used for cell synthesis during the start-up phase, whereas only 20% substrate was consumed during the steady state operation. The Reactor had certain effect on the removal of pathogenic species, but it was necessary to adopt appropriate post-disinfection measures to guarantee the effluent safety. CABR is a suitable technology for decentralized domestic sewage treatment from rural areas of China.
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effects of operational factors on soluble microbial products in a carrier Anaerobic Baffled Reactor treating dilute wastewater
2008Co-Authors: Huajun Feng, Chengran Fang, H U Lifang, Dan Shan, H E Yonghua, Dongsheng ShenAbstract:Abstract The effects of feed strength, hydraulic residence time (HRT), and operational temperatures on soluble microbial product (SMP) production were investigated, to gain insights into the production mechanism. A carrier Anaerobic Baffled Reactor (CABR) treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9-18 h, and temperatures of 10–28°C. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature (28°C), SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10°C, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand (SCOD) ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.
Liu Lin - One of the best experts on this subject based on the ideXlab platform.
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effects of hydraulic retention time and influent alkalinity on the performance of bio electrochemical system assisted Anaerobic Baffled Reactor
2016Co-Authors: Zhang Jingrui, Zhu Gefu, Jha Ajay Kumar, Liu Lin, Pan Xiaofang, Liu ChaoxiangAbstract:AbstractThe effect of hydraulic retention time (HRT) and influent alkalinity on the performance of bio-electrochemical system assisted Anaerobic Baffled Reactor (BES-ABR) was investigated in this study. The results indicated that as the HRT and influent alkalinity increase, COD removal efficiencies were enhanced correspondingly. The maximum COD removal efficiency of 97.4% was obtained at HRT of 48 h and COD of 4,000 mg/L. The maximum COD removal efficiency of 87.5% was obtained at influent alkalinity of 1,300 mg CaCO3/L and COD of 5,000 mg/L. Analysis of microbial community suggested that electrogenic micro-organisms were responsible for the better performance and stability of the system. The establishment and performance of this novel and efficient partial two-phase separation of BES-ABR strongly depended on the regulation of HRT and influent alkalinity.
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hydrogen and methane production in a bio electrochemical system assisted Anaerobic Baffled Reactor
2014Co-Authors: Zou Ran, Zhu Gefu, Jha Ajay Kumar, Liu Chaoxiang, Liu LinAbstract:Abstract In this study, a new process was proposed to enhance the stability and efficiency of an Anaerobic Baffled Reactor (ABR). The process was examined in a four equal compartments ABR with total volume of 3.46 L. The first compartment was operated for fermentative hydrogen production and the last three compartments were used as continuous singer chamber microbial electrolysis cells (MECs) for methanogenesis. The system was operated at 35 ± 1 °C and hydraulic retention time (HRT) of 24 h with influent chemical oxygen demand (COD) concentration of 3500 mg/L–4000 mg/L. The results indicated that the proportion of hydrogen in the first compartment was 20.7% and proportions of methane in the last three compartments were 98.0%, 93.6% and 70.1%, respectively. A total of 98.0% of COD removal rate was achieved as well. Hence, this new system has following advantages: hydrogen production with cleaner effluent, high COD removal rate, and net methane production for practical use.