Showing papers on "Bioreactor published in 2016"
TL;DR: This is the first review article that combines the optimization approaches for all three possible products from the anaerobic digestion for producing volatile fatty acids (VFAs) and biohydrogen.
224 citations
TL;DR: The outcomes from the current work demonstrate the potential of PPB for continuous domestic (and possibly industrial) wastewater treatment and nutrient recovery, and technical challenges include the in situ COD supply in a continuous reactor system, as well as efficient light delivery.
148 citations
TL;DR: It is shown that crude glycerol from soap production could be efficiently converted to single cell oil without any prior purification.
135 citations
TL;DR: The presented integrated system demonstrates the feasibility of substantial net fixation of carbon dioxide and conversion of gaseous feedstocks to lipids for biodiesel production and can be used for the economical conversion of waste gases from steel mills to valuable liquid fuels for transportation.
Abstract: In the quest for inexpensive feedstocks for the cost-effective production of liquid fuels, we have examined gaseous substrates that could be made available at low cost and sufficiently large scale for industrial fuel production. Here we introduce a new bioconversion scheme that effectively converts syngas, generated from gasification of coal, natural gas, or biomass, into lipids that can be used for biodiesel production. We present an integrated conversion method comprising a two-stage system. In the first stage, an anaerobic bioreactor converts mixtures of gases of CO2 and CO or H2 to acetic acid, using the anaerobic acetogen Moorella thermoacetica The acetic acid product is fed as a substrate to a second bioreactor, where it is converted aerobically into lipids by an engineered oleaginous yeast, Yarrowia lipolytica We first describe the process carried out in each reactor and then present an integrated system that produces microbial oil, using synthesis gas as input. The integrated continuous bench-scale reactor system produced 18 g/L of C16-C18 triacylglycerides directly from synthesis gas, with an overall productivity of 0.19 g⋅L(-1)⋅h(-1) and a lipid content of 36%. Although suboptimal relative to the performance of the individual reactor components, the presented integrated system demonstrates the feasibility of substantial net fixation of carbon dioxide and conversion of gaseous feedstocks to lipids for biodiesel production. The system can be further optimized to approach the performance of its individual units so that it can be used for the economical conversion of waste gases from steel mills to valuable liquid fuels for transportation.
133 citations
TL;DR: The results of this study suggest that woodchip denitrification followed by steel byproduct filtration is an effective treatment technology for nitrate and phosphate removal in subsurface drainage.
117 citations
TL;DR: An osmotic membrane bioreactor-reverse osmosis (OMBR-RO) hybrid system integrated with periodic microfiltration (MF) extraction was evaluated for simultaneous phosphorus and clean water recovery from raw sewage, resulting in a stable biological performance and an increase in water flux during OMBR operation.
112 citations
TL;DR: The performance of a laboratory-scale anaerobic bioreactor was investigated to determine methane (CH4) content in biogas yield from digestion of organic fraction of municipal solid waste (OFMSW), aimed to focus on the effects of various factors, such as pH, moisture content (MC), total volatile solids (TVS), volatile fatty acids (VFAs), and CH4 fraction onBiogas production.
94 citations
TL;DR: It is concluded that plant carbon source addition for all types of CWs and bioreactors can improve the nitrate removal efficiency to some extent, and the dosing method of plant carbon sources for denitrification should be further studied and optimized in the future.
Abstract: Water quality standard for nitrate becomes more and more strict, and the plant carbon source is widely used for denitrification by constructed wetland (CW) and bioreactor. However, the nitrate removal efficiency by different types of plant carbon source are not evaluated comprehensively. Denitrification performance of different plant carbon sources, and the influence of dosing method and pretreatment are thoroughly reviewed in this paper, which aims to investigate the accurate utilization of plant carbon source for nitrogen (as nitrate) removal. It is concluded that plant carbon source addition for all types of CWs and bioreactors can improve the nitrate removal efficiency to some extent, and the dosing method of plant carbon source for denitrification should be further studied and optimized in the future. The popular carbon sources for CW and bioreactor denitrification enhancement are woodchip, chopped macrophytes, crop plants, macrophytes litters, etc. The recommended optimum C:N ratios for CW and bioreactor are 4.0:5.0 and 1.8:3.0, respectively. The physical and biological pretreatments are selected to supply organic carbon for long-term denitrification.
91 citations
TL;DR: A novel method of two-phase anaerobic digestion where the acid reactor is operated at low pH 4.0 was proposed and investigated to examine the possibility of efficient degradation of lactate and to identify their optimal operating conditions.
87 citations
TL;DR: Pre-exposure to Cu(II) in the absence of substrates strongly inhibited anammox activity, however, the presence of NO2(-) significantly enhanced Cu( II) inhibition, and such conditions should be avoided to minimize the disturbance of the anamm ox process.
86 citations
TL;DR: It is concluded that H2/CO2 methanation was the fastest methanogenic step in digested manure and sewage sludge system with Methanomicrobiales as dominant methanogens, while granular sludgeWith Methanobacteriales as Dominant methanogen contributed to the fastest formate meetinghanation.
TL;DR: By introducing a heterologous oxidoreductase pathway and enabling starvation adaptation, this study obtained a Y. lipolytica strain that can use xylose as a sole carbon source and produce over 15 g/L of lipid in bioreactor fermentations and form the basis for further engineering to enhancexylose catabolic rates and conversion.
Abstract: The conversion of lignocellulosic sugars, in particular xylose, is important for sustainable fuels and chemicals production. While the oleaginous yeast Yarrowia lipolytica is a strong candidate for lipid production, it is currently unable to effectively utilize xylose. By introducing a heterologous oxidoreductase pathway and enabling starvation adaptation, we obtained a Y. lipolytica strain, E26 XUS, that can use xylose as a sole carbon source and produce over 15 g/L of lipid in bioreactor fermentations (29.3% of theoretical yield) with a maximal lipid productivity of 0.19 g/L/h. Genomic sequencing and genetic analysis pointed toward increases in genomic copy number of the pathway and resulting elevated expression levels as the causative mutations underlying this improved phenotype. More broadly, many regions of the genome were duplicated during starvation of Yarrowia. This strain can form the basis for further engineering to enhance xylose catabolic rates and conversion. Finally, this study also reveals the flexibility and dynamic nature of the Y. lipolytica genome, and the means at which starvation can be used to induce genomic duplications.
TL;DR: The used of fixed bed biofilm not only obviated the need of additional solid/liquid separation in the side-stream for salt accumulation control and phosphorus recovery, but effectively quarantined the biomass from the FO membrane, achieving a significant reduction in FO membrane fouling in the BF-FOMBR.
TL;DR: Results show potential adverse effects of increase in the bioreactor salinity to 15g/L (as NaCl) on the performance of AnMBR with respect to chemical oxygen demand removal, biogas production, and the removal of most hydrophilic TrOCs.
TL;DR: The results suggest that salinity build-up during HR-MBR operation could be managed by allowing for the proliferation of halotolerant/halophilic bacteria.
TL;DR: The hybrid MBBR-MBR ap performed best regarding chemical oxygen demand (COD) and total phosphorus (TP) removals, with values of 85.82 ±-2.12% and 81.42 ± 3.85%, respectively.
TL;DR: In this paper, a dynamic membrane (DM) bioreactor was operated to evaluate the anaerobic treatment of a synthetic municipal wastewater at ambient temperature, which achieved average organic removals higher than 80% and 90% for total COD and filtered COD.
TL;DR: The co-existing anaerobic fermentative bacteria with the ability to use lactate as electron donor could explain the differences between actual lactate consumption and what would be expected based solely on sulfate reduction.
TL;DR: The present research work highlights immobilization techniques, reactor setup, enzyme stability under immobilized conditions, the hydrodynamics of MBR, and its application, particularly, in the field of sugar, starch, drinks, milk, pharmaceutical industries and energy generation.
Abstract: Biocatalytic membrane reactors have been widely used in different industries including food, fine chemicals, biological, biomedical, pharmaceuticals, environmental treatment and so on. This article gives an overview of the different immobilized enzymatic processes and their advantages over the conventional chemical catalysts. The application of a membrane bioreactor (MBR) reduces the energy consumption, and system size, in line with process intensification. The performances of MBR are considerably influenced by substrate concentration, immobilized matrix material, types of immobilization and the type of reactor. Advantages of a membrane associated bioreactor over a free-enzyme biochemical reaction, and a packed bed reactor are, large surface area of immobilization matrix, reuse of enzymes, better product recovery along with heterogeneous reactions, and continuous operation of the reactor. The present research work highlights immobilization techniques, reactor setup, enzyme stability under immobili...
TL;DR: The overall performance of the SMB-OsMBR hybrid system using MgCl2 coupled with Triton X-114 as the draw solution demonstrates its potential application in wastewater treatment.
TL;DR: The results showed that moderate and intermittent pre-aeration produces a positive effect both on methane potential and in the kinetics of reaction, which is a necessary and unavoidable step in closing the material cycle.
TL;DR: High ammonium loading, low DO ( −1 ) and optimal pH value are the practical way to accumulate the desirable AOB and realize the partial nitrification in anaerobic LFL treatment bioreactors.
TL;DR: Given toxicity of sulfate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution.
TL;DR: It is demonstrated that high-density mammalian cell cultures could be maintained for long-term protein production without pH control and culture pH could be potentially modulated via adjusting residual glucose levels and CO2 stripping capability in perfusion cultures.
TL;DR: This is the first review study to correlate the idea into an anaerobic membrane bioreactor which is expected to guide future research pathways regarding anaerilic process and its bioproducts.
TL;DR: It is suggested that additional attention should be paid to prevent sludge from washout if redox mediator (RM) was practically used to remediate the anaerobic reactor inhibited by azo dyes.
TL;DR: In this paper, the main constituent of whey is lactose, which is responsible for high biological oxygen demand and chemical oxygen demand (COD) values, therefore, without going to its direct disposal into aquatic system, synthesis of nutraceuticals from lactose is considered a commendable challenge.
Abstract: Due to stricter environmental legislation and implementation of the “waste valorization” concept, recycling of dairy effluent, whey, has drawn a considerable attention. The main constituent of whey is lactose, which is responsible for high biological oxygen demand (BOD) and chemical oxygen demand (COD) values. Therefore, without going to its direct disposal into aquatic system, synthesis of nutraceuticals from lactose is considered a commendable challenge. Lactose-derived nutraceuticals, such as galacto-oligosaccharide (GOS), lactulose, lactitol, lactosucrose, lactobionic acid, gluconic acid, lactone, and tagatose, have been synthesized through different chemical and biochemical reactions, such as hydrolysis, transgalactosylation, oxidation, reduction, isomerization, and hydrogenolysis, considering raw whey or isolated lactose as feedstock. Pure biocatalyst (enzyme) and inorganic catalyst have been used for the synthesis of lactose-based nutraceuticals by different types of operations, such as conventional batch and continuous bioreactors with free catalyst, continuous packed bed bioreactor with immobilized catalyst, moving bed reactor, and membrane-assigned bioreactor. Moreover, in many cases, lactose-based nutraceuticals (lactic acid, lactosucrose, lactobionic acid, gluconic acid, and tagatose) have been synthesized by microbial fermentation process. Free microbial cell in batch and continuous fermentor and whole cell immobilized packed bed bioreactor have been used for this purpose. This review presents and compares different process-related technological aspects for synthesis of lactose-derived nutraceuticals from whey.
TL;DR: Synergistic interaction between SRB (Desulfovibrio desulfuricans) and co-existing fermentative bacteria could be the key factor for the utilization of complex organic substrate (maize straw) as carbon and nutrients source for sulfate reduction.
TL;DR: In this paper, the authors scaled up the production of pectinases in packed-bed bioreactors, from 12 to 30 kg of dry substrate, the biggest scale yet reported for Pectinase production.
TL;DR: The mediocre results of methane's production led to the conclusion that autoclaving and microwaving resulted in the hydrolysis of a significant fraction of non-biodegradable organic substances recalcitrant to anaerobic digestion.