Journal articles: 'System of anaerobicaerobic bioreactors'

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Al-Rayes, Aghyad W., Kerry A. Kinney, A. Frank Seibert, and Richard L. Corsi. "Load Dampening System for Vapor Phase Bioreactors." Journal of Environmental Engineering 127, no. 3 (March 2001): 224–32. http://dx.doi.org/10.1061/(asce)0733-9372(2001)127:3(224).

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FUNADA, Tadashi, Jiro HIRANO, Ron HASHIZUME, and Yukihisa TANAKA. "Development of Bioreactors for Water/Oil Heterogeneous System." Journal of Japan Oil Chemists' Society 41, no. 5 (1992): 423–27. http://dx.doi.org/10.5650/jos1956.41.423.

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Kitamura, Yutaka, Dan Paquin, Loren Gautz, and Tung Liang. "A rotational hot gas heating system for bioreactors." Biosystems Engineering 98, no. 2 (October 2007): 215–23. http://dx.doi.org/10.1016/j.biosystemseng.2007.07.005.

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Pavlou, Stavros. "Microbial competition in bioreactors." Chemical Industry and Chemical Engineering Quarterly 12, no. 1 (2006): 71–81. http://dx.doi.org/10.2298/ciceq0601071p.

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Competition for nutrients and other resources is an interaction common among microbial species growing together in the same environment. Such an environment can be created in the laboratory in a bioreactor in order to study this type of interaction and its effect on the microorganisms. Competition tends to eliminate species from the system. The main question then is whether the competing microbial species can coexist and under what conditions. The number of nutrients for which the microorganisms compete plays an important role, while periodic oscillations and spatial heterogeneity have a favorable effect on coexistence.

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Park, Jungsu, and Kerry A. Kinney. "Evaluation of Slip Feed System for Vapor-Phase Bioreactors." Journal of Environmental Engineering 127, no. 11 (November 2001): 979–85. http://dx.doi.org/10.1061/(asce)0733-9372(2001)127:11(979).

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Ferrero, Giuliana, Hector Monclús, Gianluigi Buttiglieri, Joaquim Comas, and Ignasi Rodriguez-Roda. "Automatic control system for energy optimization in membrane bioreactors." Desalination 268, no. 1-3 (March 2011): 276–80. http://dx.doi.org/10.1016/j.desal.2010.10.024.

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Cleland, N., and S. O. Enfors. "A biological system for studies on mixing in bioreactors." Bioprocess Engineering 2, no. 3 (1987): 115–20. http://dx.doi.org/10.1007/bf00387253.

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Thanapornsin, Thanawat, Likit Sirisantimethakom, Lakkana Laopaiboon, and Pattana Laopaiboon. "Effectiveness of Low-Cost Bioreactors Integrated with a Gas Stripping System for Butanol Fermentation from Sugarcane Molasses by Clostridium beijerinckii." Fermentation 8, no. 5 (May 8, 2022): 214. http://dx.doi.org/10.3390/fermentation8050214.

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The effectiveness of column bioreactors for butanol fermentation from sugarcane molasses by Clostridium beijerinckii TISTR 1461 was investigated. This fermentation was operated at an initial pH of 6.5 and temperature of 37 °C under anaerobic conditions. A 1-L bubble column bioreactor was used with various gas circulation rates ranging from 0.2 to 1.0 L/min. The highest butanol concentration (PB, 8.72 g/L), productivity (QB, 0.24 g/L∙h) and yield (YB/S, 0.21 g/g) were obtained with a gas circulation of 0.2 L/min. To improve butanol production efficiency, gas-lift column bioreactors with internal and external loops at 0.2 L/min of circulating gas were used. Higher PB (10.50–10.58 g/L), QB (0.29 g/L∙h) and YB/S (0.22–0.23 g/g) values were obtained in gas-lift column bioreactors. These values were similar to those using a more complex 2-L stirred-tank bioreactor (PB, 10.10 g/L; QB, 0.28 g/L h and YB/S, 0.22 g/g). Hence, gas-lift column bioreactors have potential for use as low-cost fermenters instead of stirred-tank bioreactors for butanol fermentation. When the gas-lift column bioreactor with an internal loop was coupled with a gas stripping system, it yielded an enhanced PB and sugar consumption of approximately 9% and 7%, respectively, compared to a system with no gas stripping.

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Sarazen, Jillian C., Joshua W. Faulkner, and Stephanie E. Hurley. "Evaluation of Nitrogen and Phosphorus Removal from a Denitrifying Woodchip Bioreactor Treatment System Receiving Silage Bunker Runoff." Applied Sciences 10, no. 14 (July 12, 2020): 4789. http://dx.doi.org/10.3390/app10144789.

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Leachate and storm-driven runoff from silage storage bunkers can degrade receiving water bodies if left untreated. This study evaluated a novel treatment system consisting of three treatment tanks with a moving-bed biofilm reactor and paired side-by-side denitrifying woodchip bioreactors for the ability to reduce influent nutrient mass loads. Flow-based samples were taken at four locations throughout the system, at the inflow to the first tank, outflow from the tanks prior to entering the woodchip bioreactors, and from the outflows of both bioreactors. Samples were analyzed for concentrations of nitrogen (N) and phosphorus (P) species. Inflow concentrations were reduced from the bioreactor outflows by an average of 35% for total N (TN) and 16% for total P (TP) concentrations on a storm event basis. The treatment system cumulatively removed 76% of the TN mass load, 71% of the nitrite + nitrate-N (NO2−+NO3−-N) load, 26% of the TP mass load, and 19% of the soluble reactive P load, but was a source of ammonium-N, based on the monitoring of 16 storm events throughout 2019. While the system was effective, very low NO2−+NO3−-N concentrations in the silage bunker runoff entered the bioreactors, which may have inhibited denitrification performance.

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Arshi, Simin, Mehran Nozari-Asbemarz, and Edmond Magner. "Enzymatic Bioreactors: An Electrochemical Perspective." Catalysts 10, no. 11 (October 24, 2020): 1232. http://dx.doi.org/10.3390/catal10111232.

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Biocatalysts provide a number of advantages such as high selectivity, the ability to operate under mild reaction conditions and availability from renewable resources that are of interest in the development of bioreactors for applications in the pharmaceutical and other sectors. The use of oxidoreductases in biocatalytic reactors is primarily focused on the use of NAD(P)-dependent enzymes, with the recycling of the cofactor occurring via an additional enzymatic system. The use of electrochemically based systems has been limited. This review focuses on the development of electrochemically based biocatalytic reactors. The mechanisms of mediated and direct electron transfer together with methods of immobilising enzymes are briefly reviewed. The use of electrochemically based batch and flow reactors is reviewed in detail with a focus on recent developments in the use of high surface area electrodes, enzyme engineering and enzyme cascades. A future perspective on electrochemically based bioreactors is presented.

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Oyanguren, I., S. Castañón, A. García-Ocaña, R. Vasavada, and I. Urreta. "SYSTEM FOR THE PRODUCTION OF TRANSGENIC BY2 CELLS IN BIOREACTORS." Acta Horticulturae, no. 865 (June 2010): 357–60. http://dx.doi.org/10.17660/actahortic.2010.865.51.

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Holobar, Andrej, Bernhard H. Weigl, Wolfgang Trettnak, Roman Benes̆, Hartmut Lehmann, Nena V. Rodriguez, Arnold Wollschlager, Paul O'Leary, Peter Raspor, and Otto S. Wolfbeis. "Experimental results on an optical pH measurement system for bioreactors." Sensors and Actuators B: Chemical 11, no. 1-3 (March 1993): 425–30. http://dx.doi.org/10.1016/0925-4005(93)85283-g.

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Ellis, Timothy G., Barth F. Smets, Benjamin S. Magbanua, and C. P. Leslie Grady. "Changes in measured biodegradation kinetics during the long-term operation of completely mixed activated sludge (CMAS) bioreactors." Water Science and Technology 34, no. 5-6 (September 1, 1996): 35–42. http://dx.doi.org/10.2166/wst.1996.0532.

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Two completely mixed activated sludge (CMAS) bioreactors, one with an aerobic selector and one without, were operated for approximately twelve and sixteen months, respectively. Extant biodegradation kinetics for several compounds were periodically tested using a batch respirometric procedure. Kinetic parameters from the CMAS unit without a selector showed considerable variability (standard deviation of ± 50%) even though it was operated at steady state (i.e. constant HRT, SRT, organic loading, etc.) for the duration of the study. At first, there was a large discrepancy between the kinetic parameters of the two bioreactors. Phenol and 4-chlorophenol were biodegraded according to Monod kinetics in the selector system and Andrews (inhibitory) kinetics in the non-selector system, and the μ^ and KS values were significantly greater in the selector system. The kinetic parameter values of the two systems converged, however, when the xenobiotic compounds were no longer fed to the selector in that system but were fed to the main bioreactor. After this switch, phenol and 4-chlorophenol followed inhibitory kinetics in both systems. The lack of inhibition when phenol and 4-chlorophenol were fed to the selector suggests that, contrary to conventional wisdom, bioreactors which have a concentration gradient (e.g. plug flow, sequencing batch, and tanks in series bioreactors) may be more resistant to inhibition.

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Ritonja, Jožef. "Adaptive Control of CO2 Production during Milk Fermentation in a Batch Bioreactor." Mathematics 9, no. 15 (July 21, 2021): 1712. http://dx.doi.org/10.3390/math9151712.

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The basic characteristic of batch bioreactors is their inability to inflow or outflow the substances during the fermentation process. This follows in the simple construction and maintenance, which is the significant advantage of batch bioreactors. Unfortunately, this characteristic also results in the inability of the current industrial and laboratory batch bioreactors to control fermentation production during the process duration. In some recent studies, it was shown that changing the temperature could influence the execution of the fermentation process. The presented paper shows that this phenomenon could be used to develop the closed-loop control system for the fermentation production control in batch bioreactors. First, based on theoretical work, experiments, and numerical methods, the appropriate structure of the mathematical model was determined and parameters were identified. Next, the closed-loop control system structure for batch bioreactor was proposed, and the linear and adaptive control system based on this structure and the derived and identified model were developed. Both modeling and adaptive control system design are new and represent original contributions. As expected, due to the non-linearity of the controlled plant, the adaptive control represents a more successful approach. The simulation and experimental results were used to confirm the applicability of the proposed solution.

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Vang, Boah, Nathan Frank, Mark Jones, Brian Nankervis, and Claire Coeshott. "Expansion and cellular characterization of primary human adherent cells in the Quantum® Cell Expansion System, a hollow-fiber bioreactor system." Journal of Biological Methods 7, no. 2 (April 8, 2020): e130. http://dx.doi.org/10.14440/jbm.2020.329.

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Primary adherent cell types can be expanded in the Quantum® Cell Expansion System (Quantum system), an automated platform that utilizes a hollow-fiber bioreactor. This system can replace manual cell culture and produce cells that retain their phenotypes and functionality. Bone- marrow-derived and adipose-derived mesenchymal stem/stromal cells have previously been successfully expanded on the Quantum system. We have now successfully used the Quantum system to expand fibroblasts and myoblasts. Hollow-fiber bioreactors were coated with adherence-supporting proteins, and then cells were loaded and expanded in the appropriate growth medium for 7 to 15 d. Cells were harvested from the bioreactors using enzymatic reagents. Harvested cell yields ranged from 100 × 106 to 1 × 109 cells, with viability typically above 90%. The number of doublings obtained from Quantum system harvests ranged from 4 to 9. The Quantum system is a functionally closed expansion system that can reduce contamination due to minimal interventions and can automate the culture process to reduce labor and reagent costs.

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O'Reilly, Kirk T., Rakesh Kadakia, Roger A. Korus, and Ronald L. Crawford. "Utilization of Immobilized-Bacteria to Degrade Aromatic Compounds Common to Wood-Treatment Wastewaters." Water Science and Technology 20, no. 11-12 (November 1, 1988): 95–100. http://dx.doi.org/10.2166/wst.1988.0271.

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The utilization of immobilized bacterial cells to remove toxic compounds from contaminated water is reviewed. A microbial biofilm capable of degrading the wood preservative pentachlorophenol (PCP) was developed in an aquatic system exposed to the biocide. The ability of the biofilm to function in a variety of bioreactors was tested. PCP and other aromatic compounds were degraded in the reactors. Large-scale bioreactors developed following these initial studies are currently in operation decontaminating water associated with wood-treatment facilities. Pure cultures of bacteria capable of degrading PCP or p-cresol have been immobilized in calcium alginate. Complete degradation of the target compounds occurred in both batch and continuous bioreactors. Studies indicate that it should be possible to customize bioreactors for decontamination of specific waste streams by immobilizing the proper bacteria.

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Ritonja, Jožef, Andreja Goršek, and Darja Pečar. "Model Reference Adaptive Control for Milk Fermentation in Batch Bioreactors." Applied Sciences 10, no. 24 (December 20, 2020): 9118. http://dx.doi.org/10.3390/app10249118.

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This paper presents the advanced control theory’s original utilisation to realise a system that controls the fermentation process in batch bioreactors. Proper fermentation control is essential for quality fermentation products and the economical operation of bioreactors. Batch bioreactors are very popular due to their simple construction. However, this simplicity presents limitations in implementing control systems that would ensure a controlled fermentation process. Batch bioreactors do not allow the inflow/outflow of substances during operation. Therefore, we have developed a control system based on a stirrer drive instead of material flow. The newly developed control system ensures tracking of the fermentation product time course to the reference trajectory by changing the stirrer’s speed. Firstly, the paper presents the derivation of the enhanced mathematical model suitable for developing a control system. A linearisation and eigenvalue analysis of this model were made. Due to the time-consuming determination of the fermentation model and the variation of the controlled plant during operation, the use of adaptive control is advantageous. Secondly, a comparison of different adaptive approaches was made. The model reference adaptive control was selected on this basis. The control theory is presented, and the control realisation described. Experimental results obtained with the laboratory batch bioreactor confirm the advantages of the proposed adaptive approach compared to the conventional PI-control.

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Chorukova, Elena, Ivan Simeonov, and Lyudmila Kabaivanova. "Volumes Ratio Optimization in a Cascade Anaerobic Digestion System Producing Hydrogen and Methane." Ecological Chemistry and Engineering S 28, no. 2 (June 1, 2021): 183–200. http://dx.doi.org/10.2478/eces-2021-0014.

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Abstract As focus of humans has turned to renewable energy, the role of anaerobic digestion has started to become economically viable. Reducing the volume of agro-wastes for the generation of gaseous and liquid fractions with energy carriers and valuable products is an enormous challenge. A two-stage anaerobic digestion process consisting of hydrogenic stage followed by methanogenic stage was studied in a laboratory scale. Five simple nonlinear models of this continuous cascade process were studied in order to determine the optimal ratio of working volumes of bioreactors, in view of maximising energy production. This ratio was reported for all adopted models. The optimal ratio (maximal energy production criterion) depends of the adopted mathematical model. Static characteristics of both bioreactors were obtained using Symbolyc toolbox of Matlab. Numerical experiments concerning dynamics of the main variables of both bioreactors for these models using Simulink of Matlab are performed for different step changes of the dilution rate of the first bioreactor, together with the influence of the substrate (acetate) inhibition for one of the models. The value of the constant of inhibition plays an important role on the admissible interval of the dilution rate. The developed idea could serve for optimally designed experiments of anaerobic digestion for production of hydrogen and methane from lignocelluloses wastes (wheat straw) in two phase process.

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Zaburko, J., G. Łagód, M. K. Widomski, J. Szulżyk-Cieplak, B. Szeląg, and R. Babko. "Modeling and optimizations of mixing and aeration processes in bioreactors with activated sludge." Journal of Physics: Conference Series 2130, no. 1 (December 1, 2021): 012027. http://dx.doi.org/10.1088/1742-6596/2130/1/012027.

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Abstract Mixing aimed at homogenization of the volume of bioreactors with the activated sludge is of great importance for the proper course of the wastewater treatment process. It affects both the efficiency of pollutants removal and the properties of the activated sludge related to its sedimentation. The mixing process in bioreactors can be carried out in different ways. In batch bioreactors in the aeration phase or flow bioreactors in aerobic chambers, mixing is carried out through aeration systems. These systems should aerate the activated sludge flocs for efficient biological treating of wastewater, as well as effectively homogenize the volume of the bioreactor. Hence, it is important to choose such a design of the aeration system and its operation settings that provide the amount of air ensuring the exact amount of oxygen for the implementation of technological processes, counteract sedimentation of sludge at the bottom of the reactor, are reliable as well as economical in operation (demand of electric energy). The paper presents the model studies aimed at optimization of the design and settings of aeration and mixing systems used in active sludge bioreactors.

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CHANG, CHIH-HUNG, CHIEN-CHENG LIN, CHENG-HUNG CHOU, FENG-HUEI LIN, and HWA-CHANG LIU. "NOVEL BIOREACTORS FOR OSTEOCHONDRAL TISSUE ENGINEERING." Biomedical Engineering: Applications, Basis and Communications 17, no. 01 (February 25, 2005): 38–43. http://dx.doi.org/10.4015/s101623720500007x.

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Tissue engineering is a new approach for articular cartilage repair, but the integration of engineered cartilage into the host subchondral bone is a major problem. One approach for solving this problem is to make osteochondral tissue engineering instead of cartilage tissue engineering only. The aim of the present paper was to describe two patented newly designed bioreactors for tissue-engineered osteochondral graft. The first bioreactor is double-chamber bioreactor, which is made of glass and is completely transparent. The whole system consists of one chamber for culture of chondrocytes and the other chamber for osteoblast culture. One important role for this bioreactor is to co-culture osteoblasts and chondrocytes at the same time in a biphasic scaffold. The bioreactor is modified from spinner flasks. The stirring of the magnetic bars provides medium mixing and mechanical stimulations for the cells. The second bioreactor is modified from perfusion chamber. The driven force of the medium flow is produced by siphon phenomenon. The bioreactor is composed with two parts. The first part is a modified siphon tube which can hold the biphasic scaffold for osteochondral tissue engineering. The second part is a medium reservoir bottle, which contains large amount of medium and can connect to multiple siphon tubes at the same time. The medium reservoir bottle is placed higher than the siphon tubes. The gravity will drive medium into the siphon tubes. The siphon phenomenon will make the cell-seeded scaffold covered with the medium. When the height of medium reach the height of outflow tube of the siphon tube, the medium will drain out, and the scaffold will be exposed to the air in incubator, which provides oxygen exposure. Then the gravity will make the medium refill again, the scaffold will be immersed in medium until next cycle of medium drainage out. The curve shape of the siphon tube will prevent backward bacteria contamination. The flow of the medium from reservoir through the siphon tube will produce an effect like traditional perfusion chamber bioreactor; however no power supply is necessary in this system.

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Tao, G., K. Kekre, Z. Wei, T. C. Lee, B. Viswanath, and H. Seah. "Membrane bioreactors for water reclamation." Water Science and Technology 51, no. 6-7 (March 1, 2005): 431–40. http://dx.doi.org/10.2166/wst.2005.0665.

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Singapore has been using dual membrane technology (MF/UF RO) to produce high-grade water (NEWater) from secondary treated sewage. Membrane bioreactor (MBR) has very high potential and will lead to the further improvement of the productivity and quality of high-grade water. This study was focused on the technical feasibility of MBR system for water reclamation in Singapore, making a comparison between various membrane systems available and to get operational experience in terms of membrane cleaning and other issues. Three MBR plants were built at Bedok Water Reclamation Plant with a design flow of 300 m3/day each. They were commissioned in March 2003. Three different types of submerged membranes were tested. They are Membrane A, plate sheet membrane with pore size of 0.4 μm; Membrane B, hollow fibre membrane with pore size of 0.4 μm; and Membrane C, hollow fibre membrane with pore size of 0.035 μm. The permeate quality of all the three MBR Systems were found equivalent to or better than that of the conventional tertiary treatment by ultrafiltration. MBR permeate TOC was about 2 mg/l lower than UF permeate TOC. GC-MS, GC-ECD and HPLC scan results show that trace organic contaminants in MBR permeate and UF permeate were in the same range. MBR power consumption can be less than 1 kwh/m3. Gel layer or dynamic membrane generated on the submerged membrane surface played an important role for the lower MBR permeate TOC than the supernatant TOC in the membrane tank. Intensive chemical cleaning can temporarily remove this layer. During normal operation conditions, the formation of dynamic membrane may need one day to obtain the steady low TOC levels in MBR permeate.

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Shiue, Angus, Shih-Chieh Chen, Jyh-Cheng Jeng, Likuan Zhu, and Graham Leggett. "Mixing Performance Analysis of Orbitally Shaken Bioreactors." Applied Sciences 10, no. 16 (August 12, 2020): 5597. http://dx.doi.org/10.3390/app10165597.

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This study investigated the efficacy of a novel correlation of power input, energy dissipation rate and mixing time as a potential route to identify the orbitally shaken bioreactor (OSB) system. The Buckingham’s π-theorem was used to designate and transform dimensionless Newton numbers with five relevant power input variables. These variables were empirically varied to evaluate the correlation among the dimensionless numbers. The Newton number decreases with the increased shaking frequency and filling volume. Previous work has focused on optimizing the mixing process by evaluating different shaking and agitation mixing methods. We establish a new mixing process and assessable measurement of the mixing time in the OSB. An innovative explanation of mixing time for the thermal method is proposed. The optimal mixing time is independent of the temperature of filled liquid. The dimensionless mixing number remained constant in the turbulent regime and increasing with the increased liquid viscosity and filling volume. Our findings revealed that the observed correlation is a practical tool to figure the power consumption and mixing efficiency as cell cultivation in all OSB scales and is fully validated when scaling–up system.

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Fagervik, Kaj, Mikael Rydström, Randolf Schalien, Björn Saxén, Knut Ringbom, Anette Rothberg, and Håkan Gros. "Adaptive on-line simulation of bioreactors: Fermentation monitoring and modeling system." Journal of Industrial Microbiology 14, no. 5 (May 1995): 403–11. http://dx.doi.org/10.1007/bf01569958.

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Hawari, Alaa H., Fei Du, Michael Baune, and Jorg Thöming. "A fouling suppression system in submerged membrane bioreactors using dielectrophoretic forces." Journal of Environmental Sciences 29 (March 2015): 139–45. http://dx.doi.org/10.1016/j.jes.2014.07.027.

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Butkus, Mantas, Donatas Levišauskas, and Vytautas Galvanauskas. "Simple Gain-Scheduled Control System for Dissolved Oxygen Control in Bioreactors." Processes 9, no. 9 (August 25, 2021): 1493. http://dx.doi.org/10.3390/pr9091493.

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An adaptive control system for the set-point control and disturbance rejection of biotechnological-process parameters is presented. The gain scheduling of PID (PI) controller parameters is based on only controller input/output signals and does not require additional measurement of process variables for controller-parameter adaptation. Realization of the proposed system does not depend on the instrumentation-level of the bioreactor and is, therefore, attractive for practical application. A simple gain-scheduling algorithm is developed, using tendency models of the controlled process. Dissolved oxygen concentration was controlled using the developed control system. The biotechnological process was simulated in fed-batch operating mode, under extreme operating conditions (the oxygen uptake-rate’s rapidly and widely varying, feeding and aeration rate disturbances). In the simulation experiments, the gain-scheduled controller demonstrated robust behavior and outperformed the compared conventional PI controller with fixed parameters.

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Efromson, John P., Shuai Li, and Michael D. Lynch. "BioSamplr: An open source, low cost automated sampling system for bioreactors." HardwareX 9 (April 2021): e00177. http://dx.doi.org/10.1016/j.ohx.2021.e00177.

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Zhao, Ruojin, Zhiwen Cui, Biwen Pan, Yiyi Li, Yinyan Chen, Jin Qu, Peng Jin, and Zhanwang Zheng. "Enhanced stability and nitrogen removal efficiency of Klebsiella sp. entrapped in chitosan beads applied in the domestic sewage system." RSC Advances 10, no. 67 (2020): 41078–87. http://dx.doi.org/10.1039/d0ra07732a.

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Although numerous denitrifying bacteria have been isolated and characterized, their capacity is seriously compromised by traditional inoculant addition and environmental stress in open bioreactors for wastewater treatment.

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Christianson, Laura E., Richard A. Cooke, Christopher H. Hay, Matthew J. Helmers, Gary W. Feyereisen, Andry Z. Ranaivoson, John T. McMaine, et al. "Effectiveness of Denitrifying Bioreactors on Water Pollutant Reduction from Agricultural Areas." Transactions of the ASABE 64, no. 2 (2021): 641–58. http://dx.doi.org/10.13031/trans.14011.

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HighlightsDenitrifying woodchip bioreactors treat nitrate-N in a variety of applications and geographies.This review focuses on subsurface drainage bioreactors and bed-style designs (including in-ditch).Monitoring and reporting recommendations are provided to advance bioreactor science and engineering.Abstract. Denitrifying bioreactors enhance the natural process of denitrification in a practical way to treat nitrate-nitrogen (N) in a variety of N-laden water matrices. The design and construction of bioreactors for treatment of subsurface drainage in the U.S. is guided by USDA-NRCS Conservation Practice Standard 605. This review consolidates the state of the science for denitrifying bioreactors using case studies from across the globe with an emphasis on full-size bioreactor nitrate-N removal and cost-effectiveness. The focus is on bed-style bioreactors (including in-ditch modifications), although there is mention of denitrifying walls, which broaden the applicability of bioreactor technology in some areas. Subsurface drainage denitrifying bioreactors have been assessed as removing 20% to 40% of annual nitrate-N loss in the Midwest, and an evaluation across the peer-reviewed literature published over the past three years showed that bioreactors around the world have been generally consistent with that (N load reduction median: 46%; mean ±SD: 40% ±26%; n = 15). Reported N removal rates were on the order of 5.1 g N m-3 d-1 (median; mean ±SD: 7.2 ±9.6 g N m-3 d-1; n = 27). Subsurface drainage bioreactor installation costs have ranged from less than $5,000 to $27,000, with estimated cost efficiencies ranging from less than $2.50 kg-1 N year-1 to roughly $20 kg-1 N year-1 (although they can be as high as $48 kg-1 N year-1). A suggested monitoring setup is described primarily for the context of conservation practitioners and watershed groups for assessing annual nitrate-N load removal performance of subsurface drainage denitrifying bioreactors. Recommended minimum reporting measures for assessing and comparing annual N removal performance include: bioreactor dimensions and installation date; fill media size, porosity, and type; nitrate-N concentrations and water temperatures; bioreactor flow treatment details; basic drainage system and bioreactor design characteristics; and N removal rate and efficiency. Keywords: Groundwater, Nitrate, Nonpoint-source pollution, Subsurface drainage, Tile.

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Bušs, Armands, Normunds Jēkabsons, Artūrs Šuleiko, Dagnija Loča, and Juris Vanags. "VISUALIZATION APPROACHES FOR STIRRED TANK BIOREACTORS." ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference 3 (June 20, 2019): 18. http://dx.doi.org/10.17770/etr2019vol3.4077.

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Computational Fluid Dynamics (CFD) is the analysis of fluid behaviour employing numerical solution methods. Using CFD it is possible to analyse simple and complex fluid-gas, fluid-fluid or fluid-solid interactions. Fluid dynamics is described with laws of physics in the form of partial differential equations also known as Navier-Stokes equations. Sophisticated CFD solvers transform these laws into algebraic equations which are solved by numerical methods. In this paper Ansys CFX and Fluent analysis systems as research methods are used to visualize flow patterns in a stirred tank bioreactor. The results obtained are informative and can be used to improve the yield of biomass. CFD analysis can save time and aid fluid system designing process. This approach is cheaper and faster compared to conventional build-and-test process. However, it should be noted that CFD analysis results are as accurate as the level of skill possessed by a CFD engineer therefore there are still place for hands-on testing. Authors have developed a stirred tank model and visualized flow patterns. The research presents experimental computation methods and the model setup key parameters. The developed model allows to predict flow patterns inside stirred systems and evaluate efficiency of the mixing process by analysing parameters such as velocity field, turbulence eddy frequency, shear strain rate and power input.

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Fellermann, Harold, and Luca Cardelli. "Programming chemistry in DNA-addressable bioreactors." Journal of The Royal Society Interface 11, no. 99 (October 6, 2014): 20130987. http://dx.doi.org/10.1098/rsif.2013.0987.

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We present a formal calculus, termed the chemtainer calculus , able to capture the complexity of compartmentalized reaction systems such as populations of possibly nested vesicular compartments. Compartments contain molecular cargo as well as surface markers in the form of DNA single strands. These markers serve as compartment addresses and allow for their targeted transport and fusion, thereby enabling reactions of previously separated chemicals. The overall system organization allows for the set-up of programmable chemistry in microfluidic or other automated environments. We introduce a simple sequential programming language whose instructions are motivated by state-of-the-art microfluidic technology. Our approach integrates electronic control, chemical computing and material production in a unified formal framework that is able to mimic the integrated computational and constructive capabilities of the subcellular matrix. We provide a non-deterministic semantics of our programming language that enables us to analytically derive the computational and constructive power of our machinery. This semantics is used to derive the sets of all constructable chemicals and supermolecular structures that emerge from different underlying instruction sets. Because our proofs are constructive, they can be used to automatically infer control programs for the construction of target structures from a limited set of resource molecules. Finally, we present an example of our framework from the area of oligosaccharide synthesis.

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Gago, Diego, Saladina Vilavert, María Ángeles Bernal, Conchi Sánchez, Anxela Aldrey, and Nieves Vidal. "The Effect of Sucrose Supplementation on the Micropropagation of Salix viminalis L. Shoots in Semisolid Medium and Temporary Immersion Bioreactors." Forests 12, no. 10 (October 15, 2021): 1408. http://dx.doi.org/10.3390/f12101408.

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The effect of sucrose concentration on the micropropagation of axillary shoots of willow was investigated. The following factors were examined: the culture system (semisolid medium in glass jars versus liquid medium in temporary immersion bioreactors), the type of explant (apical and basal sections), the frequency of immersion, and CO2 enrichment. Shoots and leaf growth were significantly higher in RITA® bioreactors than in the jars for all the sucrose treatments. Apical or basal sections of willow cultured in bioreactors under high light intensity (150 µmol m−2 s−1) and ventilated six times a day with CO2-enriched air were successfully proliferated without sucrose, whereas shoots cultured in jars did not proliferate well if sucrose concentration was 0.5% or lower. More roots were formed when sucrose was added to the medium. Shoots cultured in bioreactors were successfully acclimatized irrespective of the sucrose treatment and the root biomass when transferred to ex vitro conditions. This is the first report of photoautotrophic willow micropropagation, our results confirm the importance of proper gaseous exchange to attain autotrophy during in vitro propagation.

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Qiang, S., Y. Yaoting, L. Hongyin, and H. Klinkmann. "Comparative Evaluation of Different Membranes for the Construction of an Artificial Liver Support System." International Journal of Artificial Organs 20, no. 2 (February 1997): 119–24. http://dx.doi.org/10.1177/039139889702000213.

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During the past decades, many technological improvements have been made in the construction of extracorporeal liver support systems. Among these achievements, membranes of artificial capillary system, used as substrates of hepatocyte growth, aroused our interest in their application for the construction of bioreactors. The present paper studied the comparison of hepatocyte growth and function on six different membranes. Four of them are cellulose based membranes, Cuprophan, Hemophan, Cellulose acetate, and Bioflux; two are synthetic polymer SPAN and Polysulphone. Human hepatoma cell line SMMC-7721, with moderately differentiated hepatocyte-specific functions, was inoculated into the hollow fiber cartridges. These cells were allowed to attach and to grow over these membranes. It was found that there existed differences in hepatocyte immobilization and growth among these membranes. They influenced the growth and functions of hepatoma cells in vitro to some extent. These results show that membrane is an important factor in the construction of capillary membrane bioreactors for artificial liver support.

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Ferrero, G., H. Monclús, L. Sancho, J. M. Garrido, J. Comas, and I. Rodríguez-Roda. "A knowledge-based control system for air-scour optimisation in membrane bioreactors." Water Science and Technology 63, no. 9 (May 1, 2011): 2025–31. http://dx.doi.org/10.2166/wst.2011.455.

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Although membrane bioreactors (MBRs) technology is still a growing sector, its progressive implementation all over the world, together with great technical achievements, has allowed it to reach a mature degree, just comparable to other more conventional wastewater treatment technologies. With current energy requirements around 0.6–1.1 kWh/m3 of treated wastewater and investment costs similar to conventional treatment plants, main market niche for MBRs can be areas with very high restrictive discharge limits, where treatment plants have to be compact or where water reuse is necessary. Operational costs are higher than for conventional treatments; consequently there is still a need and possibilities for energy saving and optimisation. This paper presents the development of a knowledge-based decision support system (DSS) for the integrated operation and remote control of the biological and physical (filtration and backwashing or relaxation) processes in MBRs. The core of the DSS is a knowledge-based control module for air-scour consumption automation and energy consumption minimisation.

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Syed, Maira Shakeel, Christopher Marquis, Robert Taylor, and Majid Ebrahimi Warkiani. "A two-step microengineered system for high-density cell retention from bioreactors." Separation and Purification Technology 254 (January 2021): 117610. http://dx.doi.org/10.1016/j.seppur.2020.117610.

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35

Huyskens, Celine, Etienne Brauns, Erwin Van Hoof, Ludo Diels, and Heleen De Wever. "Validation of a supervisory control system for energy savings in membrane bioreactors." Water Research 45, no. 3 (January 2011): 1443–53. http://dx.doi.org/10.1016/j.watres.2010.11.001.

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36

Nalepa, Krzysztof, Maciej Neugebauer, and Piotr Sołowiej. "Dedicated control and measurement system for bioreactors to study the composting process." E3S Web of Conferences 132 (2019): 01018. http://dx.doi.org/10.1051/e3sconf/201913201018.

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During the composting process, waste biomass with high moisture content undergoes various transformation in the presence of oxygen. The composting process is analyzed in dedicated bioreactors which are air-tight facilities with external air supply. Subject to the type of composted plant material, biomass should be periodically turned to promote even aeration. The following information is required to build a model of the composting process: oxygen (air) uptake, moisture content of exhaust gas, production of carbon dioxide, ammonia and other gases in the composting process, and temperature distribution inside the bioreactor. A temperature monitoring system for a bioreactor is difficult to build due to challenging operating conditions including the airtight structure of a bioreactor, high moisture content, the operation of temperature sensors in a highly aggressive environment, problems with uninterrupted power supply for the monitoring system in a bioreactor. This article presents a patented temperature monitoring system for a bioreactor. The system’s design and structure are discussed, and recommendations for functional improvements are made.

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Wu, R. Z., M. A. Baque, and K. Y. Paek. "ESTABLISHMENT OF A LARGE-SCALE MICROPROPAGATION SYSTEM FOR ANOECTOCHILUS FORMOSANUS IN BIOREACTORS." Acta Horticulturae, no. 878 (October 2010): 167–73. http://dx.doi.org/10.17660/actahortic.2010.878.18.

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38

Zhao, Rui, Arvind Natarajan, and Friedrich Srienc. "A flow injection flow cytometry system for on-line monitoring of bioreactors." Biotechnology and Bioengineering 62, no. 5 (March 5, 1999): 609–17. http://dx.doi.org/10.1002/(sici)1097-0290(19990305)62:5<609::aid-bit13>3.0.co;2-c.

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39

Cardillo, A. B., A. M. Otálvaro, V. D. Busto, J. Rodriguez Talou, M. E. Velásquez, and A. M. Giulietti. "Brugmansia candida hairy root cultures in bioreactors as an anisodamine production system." Journal of Biotechnology 150 (November 2010): 485–86. http://dx.doi.org/10.1016/j.jbiotec.2010.09.742.

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40

Wang, Yanli, Sihai Zhao, Liang Bai, Jianglin Fan, and Enqi Liu. "Expression Systems and Species Used for Transgenic Animal Bioreactors." BioMed Research International 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/580463.

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Transgenic animal bioreactors can produce therapeutic proteins with high value for pharmaceutical use. In this paper, we compared different systems capable of producing therapeutic proteins (bacteria, mammalian cells, transgenic plants, and transgenic animals) and found that transgenic animals were potentially ideal bioreactors for the synthesis of pharmaceutical protein complexes. Compared with other transgenic animal expression systems (egg white, blood, urine, seminal plasma, and silkworm cocoon), the mammary glands of transgenic animals have enormous potential. Compared with other mammalian species (pig, goat, sheep, and cow) that are currently being studied as bioreactors, rabbits offer many advantages: high fertility, easy generation of transgenic founders and offspring, insensitivity to prion diseases, relatively high milk production, and no transmission of severe diseases to humans. Noticeably, for a small- or medium-sized facility, the rabbit system is ideal to produce up to 50 kg of protein per year, considering both economical and hygienic aspects; rabbits are attractive candidates for the mammary-gland-specific expression of recombinant proteins. We also reviewed recombinant proteins that have been produced by targeted expression in the mammary glands of rabbits and discussed the limitations of transgenic animal bioreactors.

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Simões, Lúcia Chaves, Manuel Simões, and Maria João Vieira. "A comparative study of drinking water biofilm monitoring with flow cell and Propella™ bioreactors." Water Supply 12, no. 3 (May 1, 2012): 334–42. http://dx.doi.org/10.2166/ws.2011.139.

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Monitoring of drinking water (DW) biofilm formation under different process conditions was performed using two distinct bioreactors: a Propella™ and a flow cell system. Biofilms were grown on polyvinyl chloride (PVC) and stainless steel (SS) coupons under laminar (Reynolds number: 2000) and turbulent (Reynolds number: 11000) flow. The parameters analysed were the numbers of total and cultivable bacteria. The impact of different process conditions was assessed after the biofilms reached steady-state. The number of total bacteria was mostly higher than those cultivable. Biofilm steady-state was achieved in 3 days in both bioreactors with adhesion surfaces under turbulent flow. Under laminar flow it was only achieved in 6 days. The numbers of total and cultivable bacteria in turbulent flow-generated biofilms were similar in both bioreactors, regardless of the adhesion surface tested. Under laminar flow, the Propella™ bioreactor allowed the formation of steady-state biofilms with a higher number of total and cultivable bacteria than the flow cell system. Comparing the effects of the flow regime on biofilm accumulation, only turbulent flow-generated biofilms formed on the flow cell system had a higher amount of total and cultivable bacteria than those formed under laminar flow. In terms of adhesion surface effects, a higher number of total and cultivable cells were found on PVC surfaces compared to SS when biofilms were formed in the flow cell system. Biofilm formation on PVC and SS was similar in the Propella™ system for both flow regimes.

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Mancl, Karen M., Ryan Kopp, and Olli H. Tuovinen. "Treatment of Meat-processing Wastewater with a Full-scale, Low-cost Sand/Gravel Bioreactor System." Applied Engineering in Agriculture 34, no. 2 (2018): 403–10. http://dx.doi.org/10.13031/aea.12683.

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Abstract. A full-scale sand/gravel bioreactor system was constructed to treat turkey processing wastewater. The system was designed to treat 757,000 L day-1 at a surface application rate of 6 cm day-1. Twelve 25 × 55 m sand bioreactors cover 1.6 ha on the plant property site. Construction cost was $1,426,000 (2011-2012) and operating costs were $57,600 per year. Normalized to volume of wastewater treatment, the estimated (2013) capital and operation cost is $1.03 m-3. The plant began discharging effluent in 2013. Throughout 30 months, the plant has met all effluent requirements for CBOD5, TSS, and fat, oil, and grease (FOG). FOG was always below the detection level of 5 mg L-1 in the treated effluent. Ammonia is removed by the sand/gravel bioreactors through the summer months. During the winter/spring months, supplemental ammonia removal with an ion-exchange system is used to meet effluent standards. The low cost of the sand bioreactor system makes it suitable for small-scale meat processors. Keywords: Ammonia removal, FOG (fat, oil and grease), Sand filtration, Turkey processing, Ion-exchange.

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43

Le-Clech, P., H. Alvarez-Vazquez, B. Jefferson, and S. Judd. "Fluid hydrodynamics in submerged and sidestream membrane bioreactors." Water Science and Technology 48, no. 3 (August 1, 2003): 113–19. http://dx.doi.org/10.2166/wst.2003.0176.

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As with all membrane processes, turbulence, as promoted by aeration in submerged membrane bioreactors (MBRs) or pumping in sidestream (SS) systems to produce somewhat higher effective cross-flow velocities, increases mass transfer and reduces fouling. This is manifested in an elevated critical flux, the flux at which the membrane permeability is sustained. However, the non-Newtonian nature of the sludge makes precise rheological characterisation difficult. In this study, a calculation of the appropriate hydrodynamics parameters for a SS MBR configuration is presented. Optimisation of the aeration in a submerged MBR system has been attained by defining the minimum air velocity required for Taylor bubble formation.

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Cornel, P., M. Wagner, and S. Krause. "Investigation of oxygen transfer rates in full scale membrane bioreactors." Water Science and Technology 47, no. 11 (June 1, 2003): 313–19. http://dx.doi.org/10.2166/wst.2003.0620.

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In membrane bioreactors (MBRs) for wastewater treatment the secondary clarifier is replaced by a membrane filtration. The advantage of this process is a complete removal of solids from the effluent and a small footprint due to possible high biomass concentrations (MLSS). As oxygen supply counts for more than 70% of total energy cost in municipal WWTPs the design of the aeration system is vital for efficient operation. In this respect the a-value is an important influencing factor. The a-value depends on the MLSS-concentration as shown in various publications and confirmed by own measurements in two full scale municipal MBRs with MLSS ranging from 7 and 17 kg/m3. Furthermore it must be taken into account that a-values are not static values; they vary with loading rates, surfactant concentrations, air flow rates, MLSS concentrations, etc. The average a-value at typical 12 kg/m3 MLSS for municipal MBRs is about 0.6 ± 0.1. As submerged configured MBRs are equipped with an additional coarse bubble “crossflow” aeration system for fouling control, supplementary energy is consumed. Therefore MBRs need more energy compared to conventional treatment plants. Measurements of both aeration systems show that the fine bubble aeration system is more efficient by a factor of three concerning oxygen supply compared to the coarse bubble system.

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45

Weber, Christian, Sebastian Pohl, Ralf Pörtner, Christine Wallrapp, Moustapha Kassem, Peter Geigle, and Peter Czermak. "Cultivation and Differentiation of Encapsulated hMSC-TERT in a Disposable Small-Scale Syringe-Like Fixed Bed Reactor." Open Biomedical Engineering Journal 1, no. 1 (October 29, 2007): 64–70. http://dx.doi.org/10.2174/1874120700701010064.

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The use of commercially available plastic syringes is introduced as disposable small-scale fixed bed bioreactors for the cultivation of implantable therapeutic cell systems on the basis of an alginate-encapsulated human mesenchymal stem cell line. The system introduced is fitted with a noninvasive oxygen sensor for the continuous monitoring of the cultivation process. Fixed bed bioreactors offer advantages in comparison to other systems due to their ease of automation and online monitoring capability during the cultivation process. These benefits combined with the advantage of single-use make the fixed bed reactor an interesting option for GMP processes. The cultivation of the encapsulated cells in the fixed bed bioreactor system offered vitalities and adipogenic differentiation similar to well-mixed suspension cultures.

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Nokhbatolfoghahaei, Hanieh, Mahboubeh Bohlouli, Kazem Adavi, Zahrasadat Paknejad, Maryam Rezai Rad, Mohammad Mehdi khani, Nasim Salehi-Nik, and Arash Khojasteh. "Computational modeling of media flow through perfusion-based bioreactors for bone tissue engineering." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 234, no. 12 (July 21, 2020): 1397–408. http://dx.doi.org/10.1177/0954411920944039.

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Bioreactor system has been used in bone tissue engineering in order to simulate dynamic nature of bone tissue environments. Perfusion bioreactors have been reported as the most efficient types of shear-loading bioreactor. Also, combination of forces, such as rotation plus perfusion, has been reported to enhance cell growth and osteogenic differentiation. Mathematical modeling using sophisticated infrastructure processes could be helpful and streamline the development of functional grafts by estimating and defining an effective range of bioreactor settings for better augmentation of tissue engineering. This study is aimed to conduct computational modeling for newly designed bioreactors in order to alleviate the time and material consuming for evaluating bioreactor parameters and effect of fluid flow hydrodynamics (various amounts of shear stress) on osteogenesis. Also, biological assessments were performed in order to validate similar parameters under implementing the perfusion or rotating and perfusion fluid motions in bioreactors’ prototype. Finite element method was used to investigate the effect of hydrodynamic of fluid flow inside the bioreactors. The equations used in the simulation to calculate the velocity values and consequently the shear stress values include Navier–Stokes and Brinkman equations. It has been shown that rotational fluid motion in rotating and perfusion bioreactor produces more velocity and shear stress compared with perfusion bioreactor. Moreover, implementing the perfusion together with rotational force in rotating and perfusion bioreactors has been shown to have more cell proliferation and higher activity of alkaline phosphatase enzyme as well as formation of extra cellular matrix sheet, as an indicator of bone-like tissue formation.

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Ritonja, Jozef, Andreja Gorsek, and Darja Pecar. "Control of Milk Fermentation in Batch Bioreactor." Elektronika ir Elektrotechnika 26, no. 1 (February 16, 2020): 4–9. http://dx.doi.org/10.5755/j01.eie.26.1.23377.

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In this paper, modelling and control of a batch bioreactor is studied. A main disadvantage of batch bioreactors compared to other types of bioreactors is their inability to introduce biological or/and chemical substances during operation. Therefore, possibility of bioreactor’s control by means of changing temperature was proposed, analyzed, and implemented. A new supplementary input/output dynamical mathematical model, which considers influence of heating and cooling on a bioprocess, was developed. On a basis of this model, a control system was designed and a method for tuning of the controller was suggested. Results show characteristics, applicability, and advantages of the presented approach.

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Onay, T. T., and F. G. Pohland. "Nitrogen and sulfate attenuation in simulated landfill bioreactors." Water Science and Technology 44, no. 2-3 (July 1, 2001): 367–72. http://dx.doi.org/10.2166/wst.2001.0791.

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The characteristics of leachate from landfills vary according to site-specific conditions. Leachates from old landfills are often rich in ammonia nitrogen, posing potential adverse environmental impacts in the case of uncontrolled discharge. At landfills where leachate recirculation is practiced, leachate ammonia concentrations may accumulate to higher levels than during the single pass leaching. Using leachate recirculation with system modifications, separate aerobic and anoxic zones for nitrification and both autotrophic and heterotrophic denitrification can be provided. Results from simulated landfill bioreactors indicated that both nitrogenous and sulfur compounds can be attenuated through autotrophic denitrification, and leachate nitrate concentrations of 750 mg/L reduced to less than 1 mg/L by denitrification to nitrogen gas promoting this very common process in a landfill environment results in the reduction of both leachate ammonia and sulfate concentrations.

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Low, Siok Ling, Say Leong Ong, and How Yong Ng. "Biodiesel production by microalgae cultivated using permeate from membrane bioreactors in continuous system." Water Science and Technology 69, no. 9 (February 10, 2014): 1813–19. http://dx.doi.org/10.2166/wst.2014.073.

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Microalgae in three submerged ceramic membrane photobioreactors (SCMPBRs) with different hydraulic retention times (HRTs) were fed with permeate of a submerged ceramic membrane bioreactor for a period of 3 months to investigate the lipid content and also the biodiesel quality produced at different HRTs. The lipid content, lipid productivity and fatty acid compositions for all three SCMPBRs were not significantly different at the 95% confidence level. These results suggested that insigniﬁcant change in the amount of fatty acids was observed at different HRTs that supplied varying concentration of nitrate in the medium. Among the fatty acids, palmitic acid, palmitoleic acid, oleic acid and linoleic acid were the main components, whereas stearic acid was a minor fatty acid. Since there was insignificant effect of HRT on lipid content, lipid productivity and fatty acid compositions, the optimum HRT for SCMPBRs can then be designed based on optimum nutrient removal performance and low membrane fouling propensity.

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Lepine, Christine, Laura Christianson, Kata Sharrer, and Steven Summerfelt. "Optimizing Hydraulic Retention Times in Denitrifying Woodchip Bioreactors Treating Recirculating Aquaculture System Wastewater." Journal of Environmental Quality 45, no. 3 (May 2016): 813–21. http://dx.doi.org/10.2134/jeq2015.05.0242.

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Journal articles on the topic 'System of anaerobicaerobic bioreactors'

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