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The UASB-MSBR-coagulation process was applied and industrially researched. The treatment plant had a total capacity of 70 m³/d, after achieving stable operation of 7 d, remarkable removal efficiencies were observed, with COD, SS, NH3-N, TP, and animal and vegetable oil removal rate reaching 97%, 98%, 94%, 96%, and 97%, respectively. The effluent from the treatment system met the first-level discharge standard outlined in the national “Comprehensive Wastewater Discharge Standard” (GB 8978—1996). [ABSTRACT FROM AUTHOR]

The discharge of wastewater from various industries such as petroleum and petrochemical, pollute water resources. The presence of these pollutants in water resources will cause disorders in the ecosystem and it has various risks to human health. The effluent usually contains organic matter, including phenol and its derivatives. In this study, three different types of reactors were used in the activated sludge process to study the biological removal of o-nitrophenol from the petrochemical industrial effluent. These reactors include Continuous Moving-Bed Sequencing Batch Reactor, Moving-Bed Sequencing Batch Reactor and conventional sequencing batch reactor. For this purpose, the operational indicators of each reactor were investigated and optimized. For MSBR, active sludge volume ratio (30%), aeration flowrate (18 L/min), operation time (4h), pH (7), filler to reactor volume ratio (4.7 %) and SVI (89 ml/g) were considered. Also, For C-MSBR indicators such as initial volumetric flowrate (20 ml/min), aeration flowrate (12 L/min), filler to reactor volume ratio (5.8 %) and SVI (98 ml/g) were optimized. As SBR is structurally similar to the other reactors, only initial volumetric flowrate was considered (40 ml/min) and based on the results, this reactor has better SVI (88 ml/g) than the other two reactors. Finally, based on the optimized parameters, percentage removal of ortho nitrophenol from a synthesized effluent, analogous to Karoon Petrochemical company effluent, was investigated by C-MSBR. In addition to o-nitrophenol, other chemicals such as Toluene and Benzene were also present. The results show the indicators including ortho nitrophenol percentage removal (84.7%), Chemical Oxidation Demand (COD) (94%), Biochemical Oxidation Demand (94.8%), BOD5/COD (0.57) and SVI (74.45 ml/g) comply with environmental standards and the treated effluent can be used in irrigation and agriculture by addition of one more processing step.

A nickel based alloy with molybdenum, chromium and titanium (Ni–Cr-Mo-Ti alloy) has been indigenously developed for applications related to the Indian Molten Salt Breeder Rector (IMSBR). The present work involves investigation of the interaction of the above alloy with molten fluoride salt using an in-house developed Molten Salt Corrosion Test Facility (MSCTF). In a comparative study, the indigenous alloy along with other Ni based alloys, were exposed to molten fluoride salt, FLiNaK, under static conditions at 973 K (700 °C) in MSCTF. Salient results indicate that the extent of fluoride salt attack is directly proportional to the chromium content of the above alloys. In addition, the molten fluoride salt preferentially attacks the grain boundaries of the Ni–Cr-Mo-Ti alloy although the inherent carbide/nitride precipitates can also play a major role in the corrosion mechanism. [ABSTRACT FROM AUTHOR]

The concept of Molten Salt Reactor use Th to breed fissile 233U, where an initial source of fissile material needs to be provided. However, there is no available 233U and so; the fissile fuel supply is one of the unresolved problems. Thus, it is necessary to use existing fissile materials such as 235U or Pu to produce 233U. Current studies analyze the fuel transition from 235U/Th or Pu/Th to 233U/Th and, in this context, the present work evaluates the criticality and the neutron flux of MSBR (Molten Salt Breeder Reactor) considering the fuel: (i) mix of Th and enriched U; (ii) the combination of Th and reprocessed Pu; and (iii) matrix of reprocessed Pu/minor actinides (MAs) and Th. The goal is to verify which of these fuels can be used as initial fissile supply. The MSBR core was simulated by MCNPX 2.6.0 code and the criticality model presents similar behavior of previous studies. The results show that reprocessed fuels could have a potential to be used as initial fissile supply, but these fuels present a neutron flux profile less flattens than traditional 233U/Th. It is possible that a new distribution of fuel elements may improve this profile and future simulations will be performed to evaluate this behavior. The uranium, must has high enrichment value to be used as initial seed. Other studies need be performed to evaluates the uranium enrichment and the U/Th ratio that produces similar core criticality to traditional fuel.

Preliminary results of the dynamic analysis of a two-fluid molten-salt breeder reactor (MSBR) system are presented. Based on an earlier work on the preliminary dynamic model of the concept, the model presented here is nonlinear and has been revised to accurately reflect the design exemplified in ORNL-4528. A brief overview of the model followed by results from simulations performed to validate the model is presented. Simulations illustrate stable behavior of the reactor dynamics and temperature feedback effects to reactivity excursions. Stable and smooth changes at various nodal temperatures are also observed. Control strategies for molten-salt reactor operation are discussed, followed by an illustration of the open-loop load-following capability of the molten-salt breeder reactor system. It is observed that the molten-salt breeder reactor system exhibits “self-regulating” behavior, minimizing the need for external controller action for load-following maneuvers.

A lab-scale SBR equipped with a flat sheet membrane in submerged configuration that is named MSBR was used for the treatment of composting leachate. It was fed by biologically treated leachate with overall 70-1360 mg/L Chemical Oxygen Demand (COD). The values of pH, Electrical Conductivity (EC), and Dissolved Oxygen (DO) were monitored routinely. However, analysis of total COD, Soluble COD (SCOD), Biological Oxygen Demand (BOD5), Total Suspended Solids (TSS) and Volatile Suspended Solids (VSS) was done in feed and filtrate, whenever the system reached steady state twice a week for about 6 months.In all loading rate, BOD5 concentration was less than standard limit. The removal efficiency of total COD increased in the bioreactor with time in all experiments was up to 80%.Influent SCOD varied spectacularly (50-1050mg/L) due to the leachate collection during different seasons but in the effluent, it remained relatively stable. About 60% of the feed SCOD was the non biodegradable type that was separated by the membrane.Up to 99 % further solids was removed with micropore membrane which might be mainly included in colloidal solids. The value of EC for the leachate sample was 0.86-4 mS/cm at 22 °C which decreased by membrane significantly.It was concluded that MSBR as a versatile technology with high throughput could treat composting leachate belowthe standard limit if used after proper processes.

Introduction Glucagon-like peptide-2 (GLP-2) is a known intestinal growth factor that enhances mucosal mass and function in residual small intestine after massive small bowel resection (MSBR). Luminal omega-3 (OM-3) has been shown to have some growth factor properties. It is possible that their mechanisms of action differ. Thus, we hypothesized that administering these two substances together may have a synergistic effect. Methods A total of 60 adult female Sprague–Dawley rats underwent 80% MSBR and divided as follows ( n = 15/group): Saline (Control) + regular feeds; GLP-2 + regular feeds; Saline + OM-3 enriched feeds; and GLP-2 + OM-3 enriched feeds. Five animals per group were sacrificed at 7, 14, and 28 days. Small intestine mucosa was harvested. DNA and protein content were measured (mucosal mass markers) at all three time points. Galactose and Glycine absorption were measured (functional capacity markers) at 28 days. Statistical analysis was done by ANOVA with post hoc Tukey's HSD test. Results At all three time points, DNA was increased in all treatment groups compared to control ( P < 0.05), but GLP-2 + OM-3 group did not have increased DNA content when compared to either treatments alone. At 7 and 14 d, all three treatment groups had increased protein content compared to control ( P < 0.05). At 28 d, GLP-2 + OM-3 did not have increased protein content compared to control or individual treatments ( P < 1.0). All three treatment groups had increased absorption of galactose and glycine compared to control ( P < 0.05) but not each other. Conclusions Individually, GLP-2 and OM-3 are very effective in enhancing the adaptive process by increasing mucosal mass and function, at all three time points. More importantly, clinically, GLP-2 and OM-3 increase substrate absorption in a rat model of intestinal failure. However, the combination is not synergistic. [ABSTRACT FROM AUTHOR]

The simulation of whole core depletion and continuous reprocessing of a molten salt breeder reactor (MSBR) was performed. The MSBR model was built using MCNP6, and the depletion and reprocessing simulations were modeled using CINDER90 and a Python script. The Python script was introduced to implement online reprocessing of molten salt fuel and the feeding of new fertile material with 3-day depletion intervals during the simulations. The simulation started with the reference composition from the original Oak Ridge National Laboratory MSBR design. Equilibrium compositions were obtained from depletion and reprocessing simulations 7000 days worth of data. The MSBR whole core analysis was performed at the initial and equilibrium core conditions, for various reactor design parameters such as multiplication factors, neutron flux distributions, temperature coefficients, rod worths, and power distributions. The neutronic core characteristics were analyzed using a four-factor formula applied to the two zones of the core separately. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

• A 1-D delayed neutron precursor transport model with a second-order Godunov method is added to the RELAP5 code. • The modified REALP5 code is tested by the experimental benchmarks of the MSRE. • The applicability of the code is further verified with different transient scenarios of the MSBR. The Liquid-Fueled Molten Salt Reactor (LF-MSR) with high-temperature molten salt is one of the Generation IV nuclear power systems. One of the significant differences between the LF-MSR and the Pressurized Water Reactor (PWR) is that the delayed neutron precursors (DNP) circulate in the primary loop of the LF-MSR and leads to different neutron kinetics between LF-MSR and PWR. Consequently, a system code for PWR is not applicable to LF-MSR, and the safety analysis code RELAP5-TMSR is modified by adding a one-dimensional DNP transport model to improve its applicability to LF-MSR. A second-order Godunov method is adopted in this 1-D DNP model. Then the improved code is tested with experimental benchmarks from Molten Salt Reactor Experiment (MSRE) designed and operated by Oak Ridge National Laboratory (ORNL) and the results show good consistency. Moreover, the modified RELAP5-TMSR code is applied to analyzing transient characteristics of the single-fluid Molten Salt Breeding Reactor (MSBR) so that the applicability of the modified RELAP5-TMSR code is further verified. It is concluded that the one-dimensional DNP transport model can describe effectively the movement of the DNP and the improved RELAP5-TMSR code is suitable for modeling and simulation of reactor transient responses in LF-MSR. [ABSTRACT FROM AUTHOR]

Abstract: The treatment performances and membrane fouling parameters of a membrane sequencing batch reactor (MSBR) used to treat synthetic wastewater were studied over 300days. Aerobic granular sludge ranging from 500 to 1000µm in particle diameter was cultivated after a period of regulation in operating conditions. The MSBR with aerobic granules achieved a high removal efficiency of pollutants. The emergence of aerobic granules in the MSBR system improved the membrane performance, as indicated by the fouling rate being maintained below 0.1kPad−1 when the MLSS concentration was greater than 18gL−1. The change in granule size and improved sludge settleability played an important role in sustaining the membrane permeability. Specifically, the reduced SVI led to a decrease in the supernatant TOC concentration that corresponded to a slower rise in TMP and less membrane fouling. Proteins were the primary components of EPS, while polysaccharides constituted a higher portion in SMP. In addition, the relative hydrophobicity (RH) and zeta potential increased in the sludge, while the protein to carbohydrate ratio (P/C) of both EPS and SMP increased after the formation of aerobic granules. These changes also enhanced the filterability of the mixed liquor. [Copyright &y& Elsevier]

In this study, the performance of a moving-bed sequencing batch reactor (MSBR) that removes phenol from wastewater is presented. The effects of phenol concentration (50–3325mgL−1), filling time (0–4h) and aerating time (4–18h) on the performance of the MSBR are given in terms of phenol and COD removal efficiencies. Moreover, the effect of the moving media on the overall performance of the reactor is also determined. The reactor can completely remove phenol and COD at inlet concentrations up to 3000mgphenolL−1 (6780mgCODL−1), which was the inhibition concentration, and with a 24-h cycle time. The filling time range tested here did not significantly affect phenol or COD removal. The optimum hydraulic retention time (HRT) for the MSBR is 40h and the critical phenol loading rate is 83.4gphenolm−3 h−1, which gives a phenol removal efficiency of 99%. The reactor can also withstand shock loads from slug feeding. The moving bed contribution to phenol and COD removal efficiencies was up to 28.1 and 34.7%, respectively, at the phenol loading rate of 83.4gm−3 h−1. The findings of this investigation suggest that MSBR can be a robust and promising process for effectively treating wastewaters containing inhibitor or recalcitrant compounds in industrial settings. [Copyright &y& Elsevier]

Abstract: The start-up of an Anammox process was studied in a membrane sequencing batch reactor (MSBR) in which a submerged hollow fibre membrane module was used to retain the biomass. The reactor was seed with Anammox biomass and fed using the Van de Graaf medium. During a first operating stage, salt precipitation was observed and interfered with microbial activity and caused a decrease of the nitrogen removal rate of the reactor from 100 to only 10mgl−1 per day. Salt precipitation was avoided by diminishing adequately the Ca and P concentrations of the Van de Graaf medium during the last operating stage. This action increased quickly the activity of the system, and nitrogen removal rate reached up to 710mgl−1 per day with almost full nitrite removal. Sporadic flotation of the sludge was observed in the MSBR. The use of the membrane avoided biomass wash-out from the system. Moreover, a surprising fact was that Anammox biomass did not grow in flocs in the MSBR, but in granules. This fact showed that this kind of microorganisms have a trend to grow in aggregates. Results indicated that the use of the MSBR could be a suitable system for nitrogen removal by using the Anammox reaction. [Copyright &y& Elsevier]

Abstract: The effect of dissolved oxygen (DO) level on microfiltration performance and microbial physiology was investigated in membrane-coupled sequencing batch reactors (MSBR). Two bioreactors employing anoxic/oxic (A/O) and only oxic (–O–) phase, respectively were run in parallel to elucidate how DO level does affect membrane filterability and microbial characteristics of sludge. If TMP is considered as an important parameter for the MSBR system the head loss originated from the water-level decline during the suction step should be taken into account. TMP value associated with the water-level reduction was calculated to 2.0kPa, indicating it should not be ignored in this study. When the cycles in MSBR were repeated, the A/O phase resulted in faster rise in TMP, corresponding to greater membrane fouling, compared to the –O– phase. Permeate flux as well as airflow rate proved to be a major factor affecting the membrane performance for the A/O phase. Analyses of particle size distribution and specific cake resistance indicates that the flocs in the A/O phase, smaller than in the –O– phase, tend to form a dense and compact cake on the membrane surface and give rise to a higher hydraulic resistance. Irreversible membrane fouling also developed faster in the A/O than in the –O– reactor. Analyses of microbial community by FISH and DGGE showed a significant difference in microbial community between two reactors. However, no microbial community difference was found between suspended and attached microorganisms for the same reactor. [Copyright &y& Elsevier]

Objectives: This study investigated the relationships between a mindfulness-based stress reduction meditation program for early stage breast and prostate cancer patients and quality of life, mood states, stress symptoms, and levels of cortisol, dehydroepiandrosterone-sulfate (DHEAS) and melatonin.Methods: Fifty-nine patients with breast cancer and 10 with prostate cancer enrolled in an eight-week Mindfulness-Based Stress Reduction (MBSR) program that incorporated relaxation, meditation, gentle yoga, and daily home practice. Demographic and health behavior variables, quality of life, mood, stress, and the hormone measures of salivary cortisol (assessed three times/day), plasma DHEAS, and salivary melatonin were assessed pre- and post-intervention.Results: Fifty-eight and 42 patients were assessed pre- and post-intervention, respectively. Significant improvements were seen in overall quality of life, symptoms of stress, and sleep quality, but these improvements were not significantly correlated with the degree of program attendance or minutes of home practice. No significant improvements were seen in mood disturbance. Improvements in quality of life were associated with decreases in afternoon cortisol levels, but not with morning or evening levels. Changes in stress symptoms or mood were not related to changes in hormone levels. Approximately 40% of the sample demonstrated abnormal cortisol secretion patterns both pre- and post-intervention, but within that group patterns shifted from “inverted-V-shaped” patterns towards more “V-shaped” patterns of secretion. No overall changes in DHEAS or melatonin were found, but nonsignificant shifts in DHEAS patterns were consistent with healthier profiles for both men and women.Conclusions: MBSR program enrollment was associated with enhanced quality of life and decreased stress symptoms in breast and prostate cancer patients, and resulted in possibly beneficial changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. These pilot data represent a preliminary investigation of the relationships between MBSR program participation and hormone levels, highlighting the need for better-controlled studies in this area. [Copyright &y& Elsevier]

• EQL0D for equilibrium cycle simulation was developed. • The tool enable simulation of complicated MSR refueling schemes. • The tool was verified using historical data and other existing tools. • EQL0D was applied to selected MSR concepts. In recent years, Molten Salt Reactors (MSRs), one of the Generation IV concepts, have noticeably gained in interest. Several molten salt reactor types use fuel in liquid form, bringing various advantages, notably in terms of fuel cycle. However, simulating the evolution of liquid fuel under irradiation necessitates specific tools and methods, for example to simulate the removal of insoluble fission products from the salt mixture or continuous refueling of the reactor. For this purpose, the Serpent 2-based procedure EQL0D has been developed. It is designed for both equilibrium and finite-time burn-up calculations in liquid-fueled molten salt reactors. This paper first details the most important methods implemented in the procedure to simulate liquid-fuel systems, after which the adequacy of the procedure is verified by comparing benchmark results with a comparable code. Examples of applications of this tool to the start-up and transition to closed fuel cycle of the historical single- and two-fluid Molten Salt Breeder Reactors as well as the more recent Molten Salt Fast Reactor, a fast-spectrum concept, are then presented. The obtained results show the challenge faced by thorium-cycle breeder MSRs to transition from available nuclear fuels to a closed thorium cycle, as many candidate fuels prove to be unusable for the transition to a closed cycle. [ABSTRACT FROM AUTHOR]

• Based on the two-region model of MSBR core, a core linear model is developed. • An IMC-PID controller is designed for MSBR core power control. • Particle Swarm Optimization algorithm is used to find the optimum attenuation factor a of the IMC-PID controller. Internal Model Control (IMC) is a control strategy based on process mathematical model for controller design. The design idea of IMC is to parallelize the object model with the actual object, approximate the dynamic inversion of the model by the controller, and take the inverse of the minimum phase part of the model for a single variable system, and add it to the system. As the advantages of simple structure, intuitive design, no need for accurate object model, less on-line adjustment parameters in IMC design process, to explore the application of IMC in the field of nuclear reactor control, taking the core power control of Molten Salt Breeder Reactor (MSBR) as an example, a linear model of MSBR core system is established. The IMC technology was adopted and the IMC-PID controller with Particle Swarm Optimization (PSO) algorithm was designed to control the core power. The core power control of liquid molten salt reactor under step reactivity disturbance and load tracking is studied. The results show that the IMC-PID controller can control the core power well. [ABSTRACT FROM AUTHOR]