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Petrochemical industrial wastewater presents a challenge when treated, employing the conventional activated sludge process, such as in the activated sludge process, the loss of biomass due to the harsh wastewater conditions and the inhibition caused by the elevated levels of industrial compounds. Hybrid biological reactors may present a resource to be tapped in the operation of an industrial wastewater treatment facility if integrated optimally in the treatment sequence. This paper examines possible integration scenarios of hybrid reactors in a petrochemical wastewater treatment plant in order to improve its organic removal efficiency. A pilot hybrid biological reactor was constructed using high surface area biological carrier and was operated using real wastewater streams from a wastewater treatment plant at two flow rates (400 ml/min and 240 ml/min), two dissolved oxygen levels (2.0 mg/l and 4.0 mg/l), and anaerobic conditions. The reactor was tested using raw, primary, secondary, and effluent streams from the wastewater treatment plant. The reactors were primed with wastewater from the aeration tank of the wastewater treatment plant and was operated for 10 d afterward (total 24 runs). The chemical oxygen demand cumulative removal was used to identify best integration scenario and to benchmark its performance against domestic wastewater. The best performing scenarios were identified as anaerobic (400 ml/min) for raw wastewater treatment and [(400 ml/min and dissolved oxygen (DO) 2.0 mg/l)] for secondary wastewater polishing. The results reflected the unfavorable conditions for biodegradation after the primary chemical treatment. This conclusion was confirmed upon benchmarking the hybrid reactor performance using domestic wastewater. [ABSTRACT FROM AUTHOR]

Monte Carlo methods are useful for simulating new reactor designs, but even with advances in computing, these methods still require a significant amount of time to perform transient or multiphysics calculations coupled with thermal modeling. This work demonstrates a hybrid reactor physics method that uses Monte Carlo to precalculate an initial database of fission matrix parameters, then combines these results for fast calculations on arbitrary system states. This paper extends previous work that demonstrated these methods on the Penn State Breazeale Reactor (PSBR). Approaches for reducing time and memory cost and increasing the accuracy in reproducing Monte Carlo output are considered. For modeling fuel temperature, a representative temperature distribution is used while tallying the initial fission matrix database. Different approaches for modeling the coupling between individual control rod insertions as well as control and fuel temperature effects are presented as well. Individual solutions are completed in less than 1 s on a single core, and error with respect to Monte Carlo is within 35 pcm for multiplication factor, 0.6% root-mean square, and 2.8% maximum for the normalized three-dimensional fission source distribution on critical, steady-state configurations. Further qualification on different reactor types is needed, but the simplicity and flexibility of this method make further development promising. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simulated moving bed reactors (SMBRs) are hybrid reactors that perform reaction and separation processes simultaneously in a single unit. Their high separation performance and ability to overcome equilibrium constraints on the reaction make them effective in a wide range of equilibrium reactions. This study investigated an SMBR for xylene isomerization and separation of p‐xylene from other xylene isomers (free of ethylbenzene) in the liquid phase. The effects of operating variables including temperature, switching time, and columns arrangement on the performance parameters and optimal conditions were determined. Due to the removal of products from the reaction site, the SMBR drives the chemical equilibrium toward producing more product than a conventional reactor under the same conditions. [ABSTRACT FROM AUTHOR]

The fusion and subsequent decay analysis of Z=116 superheavy nucleus formed via 48Ca+248Cm→296Lv*, 50Ti+244Pu→294Lv*,and 58Fe+232Th→290Lv* reactions is carried out using extended l-summed Wong model and dynamical cluster decay model (DCM), respectively. First of all, the experimentally available fusion-fission (A/2±20) data is adequately addressed for 296Lv* and 294Lv* superheavy nuclei using extended l-summed Wong model and the predictions are made for fusion-fission excitation function of 290Lv* nucleus. It is observed that with decrease in mass-asymmetry (ƞ), the contribution of fusion-fission component decreases. This drop is steeper for 50Ti to 58Fe as compared to that for 48Ca to 50Ti. The calculated values of compound nucleus formation probability (PCN) are highest for 48Ca followed by 50Ti and 58Fe. Finally, the mass distribution of decay fragments is studied for 296Lv*, 294Lv*, and 290Lv* nuclei using DCM at near barrier energies. A valley in ACN/2 region results in asymmetric mass distribution for 296Lv* which becomes relatively symmetric for the lighter isotope 290Lv*. [ABSTRACT FROM AUTHOR]

Indian national gamma array (INGA) and gamma detector array (GDA) have been the work horse for nuclear structure studies at IUAC. Many of these studies have revealed a variety of modes of excitations in nuclei as a function of spin, isospin and excitation energy. These excitation modes mirror different underlying symmetries and structures in nuclei for a given mix of above mentioned quantities. Further, there is a rich inter-play between these various modes or degrees of freedom and it’s a challenge to experimentally identify and theoretically comprehend the rich spectra exhibited. INGA and GDA setups have also been successfully used in recent years for studying reaction dynamics like incomplete fusion and fusion-fission in heavy ion collisions at energies of about few MeV per nucleon. [ABSTRACT FROM AUTHOR]

Highlights • A novel integrated photoelectrochemical hybrid system is proposed for multigeneration. • Integrated system products are: hydrogen, chlorine, electricity, and heat. • Thermodynamic analysis is conducted to measure the impact of key parameters on the system. • Hydrogen, chlorine, electricity, and heat generation rates and efficiencies are investigated. Abstract The primary aim of this study us to develop an integrated PV/T-photoelectrochemical-chloralkali (PEC-chloralkali) system with multigeneration benefits and evaluate its thermodynamic performance. The key component of the integrated system is the continuous type hybrid H 2 generation reactor, which is also referred to as PEC-chloralkali reactor. The hybrid reactor is capable of converting the byproducts of H 2 production into valuable products for the industry. In addition to hydrogen, the hybrid reactor can produce Cl 2 and NaOH simultaneously. The reason behind using the hybrid reactor together with PV/T in an integrated system is to maximize solar spectrum utilization by combining the advantages of the photoelectrochemical system and PV/T. The electrodes are used as electron donors to drive the photoelectrochemical reaction in the hybrid reactor. As a result, the need for additional chemicals is eliminated and the risk of any potentially harmful waste streams is minimized. The integrated system has five useful products which are hydrogen and chlorine gases, sodium hydroxide solution, heat, and electricity. The performance of the system is evaluated based on hydrogen, chlorine, heat, and electricity production rates, energy and exergy efficiencies, and exergy destruction rates at different ambient temperatures and with different total photoactive area sizes. It is seen that the present innovative hybrid multigenerational system is capable of producing 8.9 g/h H 2 and 244 g/h Cl 2 at energy and exergy efficiencies about 86% and 29%, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Four blanket benchmark mockups of a fusion–fission hybrid reactor have been established. • Distribution of TPR in the mockups was obtained by lithium glass detector method. • Distribution of TPR was assessed by using MCNP5 program and ENDF/B-VII database. • Difference between calculations and experiments in lithium hydride may be caused by lack of S(α,β) thermal neutron data. Abstract As an important parameter of neutronics integral experiment, tritium production rate could not only be used for validation of programs and evaluation database, but was also related to tritium self-consistency after the activation of the sub-critical reactor. This parameter was a key component of the sub-critical reactor design. Four blanket benchmark mockups of a fusion-fission hybrid reactor were established utilizing lithium materials, which consisted of depleted uranium/lithium hydride, uranium/lithium hydride/polyethylene, uranium/lithium hydride/graphite/iron, and uranium/Li-Pb alloy/polyethylene. Based on the Cockcroft–Walton neutron generator, the distribution of tritium production rate by D–T neutrons in the four mockups was evaluated by two pairs of different sizes lithium glass detectors. The distribution was then quantitatively assessed using MCNP5 program and ENDF/B-VII database. The tritium production rates of the mockups with lithium hydride significantly deviated from the experimental results; whereas those of the mockup with lithium-lead alloy were agree well with the experimental results. [ABSTRACT FROM AUTHOR]

Highlights • Several kind of tungsten materials were exposed to soft Z-pinch X-ray sources. • Surface swelling of W samples was observed and the swelling heights were measured. • FWDR1D code could partially expound the measured surface swelling height data. • Thermomechanical damage thresholds of W to pulsed soft X-rays are determined. Abstract In a Z-Pinch driven fusion-fission hybrid reactor (Z-FFR), a thin spherical metal shell and rare Ar buffer gas are introduced to mitigate the transient X-ray bursts to prevent the first wall from fatal damages by intense X-rays, which take almost 20% of the fusion energy yield (approximately 300 MJ). Thereby soft X-rays as well as the EUVs, are believed to become the dominant threatening sources that the first wall will suffer from. Tungsten is chosen to be the prime candidate material of the Z-FFR first wall, and has been tested on 'QG-I' facility to determine the single-shot thermomechanical damage thresholds under pulsed soft X-ray irradiations, as well as to verify and validate the modeling and calculating code 'FWDR1D'. Several tens of tungsten samples as well as zirconium samples were exposed to a variety of X-ray fluences in the range of 0.1 to 0.7 J/cm2 and with an account of more than 20 shots. The theoretical and experimental results meet well, and analysis of the results indicates that tungsten has specific thermomechanical damage thresholds with X-ray fluences in the range of 0.15 to 0.21 J/cm2 under single-shot soft X-ray irradiations. [ABSTRACT FROM AUTHOR]

Abstract Outcomes from RFX-mod, the largest Reversed Field Pinch (RFP) experiment, have shown a substantial increase of the electron and ion temperatures versus the plasma current with a trend that allows hypothesizing significant D-T fusion processes in larger devices with higher plasma current. Such a device, in which the plasma is purely ohmically heated, could act as an efficient, robust and cheap fusion neutron source with a neutron rate to be used as the basis for a Fusion-Fission Hybrid Reactor (FFHR). The peculiar features of this neutron source can be summarized as: ohmically heated plasma, toroidal field winding rated for a low magnetic field (one-two orders of magnitude lower than in Tokamaks), very simple, robust and cheap construction, simple access for Remote Handling and easy maintenance. Almost continuous neutron production, as required in a hybrid reactor, is guaranteed by a continuously pulsed operation without the need of additional current drive systems. The aim of the paper is to investigate the relationship between the machine size (major and minor device radius), the attainable stored volt-seconds and, consequently, the maximum plasma current and pulse duration. The analysis uses the experimental RFX-mod data (electron temperatures, plasma currents, loop voltages during flat top) to extrapolate the performances of larger RFP devices with significant neutron production from D-T reactions. This study shows a realistic possibility, in an inductively operated RFP of larger size than RFX-mod, with plasma current 15–20 MA and temperature ≈ 10–15 keV, to reach the level of neutron generation of a fusion-fission hybrid reactor, leading to a neutron production rate in the range of 1019 n/s and a wall neutron load of 0.2 MW/m2. [ABSTRACT FROM AUTHOR]

Highlights • Low energy radiations play important roles in chamber dynamics in Z-FFR. • Low energy radiations induce intense thermal heat loads on the first wall. • Intense thermal heat loads lead to severe thermal stresses in the first wall. • Variations of radiative opacities have great influence on the chamber dynamics. Abstract In a Z-Pinch driven fusion-fission hybrid reactor (Z-FFR), a substantial thin spherical Cu shell and rare Ar buffer gas are introduced to mitigate the transient X-ray bursts to prevent the first wall from fatal damages. Preliminary simulations indicated that the peak ion and radiation (blackbody) temperatures of the Cu shell and Ar gas are on the order of 105 and 104 K respectively, which means low energy radiations might play important roles in the radiation transport processes in the fusion chamber. Therefore multigroup transports were adopted in simulations of the chamber dynamics, and influence of low energy radiations on the chamber dynamics and resulting first wall response were investigated. The results indicated that low energy radiations have significant influence on the chamber dynamics such as distributions and evolutions of the temperatures and heat fluxes in the Ar gas. And much intenser thermal heat fluxes would be loaded on the first wall, resulting in higher temperature rises and intenser thermal stresses. In addition, practical treatments of the multigroup radiative opacities of Cu and Ar by multiplying a series of artificial factors, varying from 0.1 to 5, were adopted to evaluate the safety of the chamber. It was shown that the opacity uncertainties of Cu have much important influence on the chamber dynamics than those of Ar. The thermomechanical response in the first wall such as maximum temperature rises and stresses, as well as the corresponding lifetimes, were not able to fulfill the safety requirements while the Cu opacities were reduced by two more times. Additional schemes might be required to effectively handle the problems to finally sustain current Z-FFR designs. [ABSTRACT FROM AUTHOR]

The degradation of low concentrations of acetaldehyde while using a non-thermal plasma (NTP)/catalyst hybrid reactor system was investigated while using humidified air at ambient temperature. A series of highly active manganese-impregnated natural zeolite (Mn/NZ) catalysts were synthesized by the incipient wetness method using sonication. The Mn/NZ catalysts were analyzed by Brunauer-Emmett-Teller surface area measurements and X-ray photoelectron spectroscopy. The Mn/NZ catalyst located at the downstream of a dc corona was used for the decomposition of ozone and acetaldehyde. The decomposition efficiency of ozone and acetaldehyde was increased significantly using the Mn/NZ catalyst with NTP. Among the various types of Mn/NZ catalysts with different Mn contents, the 10 wt.% Mn/NZ catalyst under the NTP resulted the highest ozone and acetaldehyde removal efficiency, almost 100% within 5 min. Moreover, this high efficiency was maintained for 15 h. The main reason for the high catalytic activity and stability was attributed to the high dispersion of Mn on the NZ made by the appropriate impregnation method using sonication. This system is expected to be efficient to decompose a wide range of volatile organic compounds with low concentrations. [ABSTRACT FROM AUTHOR]

Mexico is one of the main citrus producers, ranking fourth in the world with approximately 7.4 million tons per year, with oranges contributing 4.08 million tons to that total. The effluents from the citrus industry have high loadings of organic matter and low pH levels. These effluents also are suitable for treatment by anaerobic digestion to reduce the organic matter and to obtain a value-added product, such as biogas. The aim of this work was to perform the anaerobic digestion of effluents from the citrus industry by using a high-rate reactor, evaluating the biogas production and use as an alternative energy source. An Anaerobic Hybrid Reactor (AHR) was used to treat the effluent from a citrus processing plant in Martínez de la Torre, Veracruz, Mexico. The AHR was operated at an organic loading rate (OLR) of 8 gCODT/Ld at steady state, obtaining a total and soluble COD removal of approximately 85%, with methane yields around 0.15 LCH4 to STP/gCODrem. An inhibitory effect was observed by the presence of D-limonene in the citrus effluent, although no pretreatment was used for elimination of this essential oil, a decrease in the COD removal and methane yields was observed due to the higher OLR. An energy estimate was obtained with the biogas, and it was found that up to 2.2% of the electricity required for the operation of a citrus processing plant can be generated using anaerobic treatment. [ABSTRACT FROM AUTHOR]

Experiments were performed in an anaerobic multiphase hybrid reactor at the mesophilic temperature (30°C–35°C) for simultaneous bioenergy recovery and antibiotic wastewater treatment. The reactor was operated for 245 d. Acclimatization was done at 24 h hydraulic retention time for 41 d. From day 42 to 113, the reactor was operated at six different organic loadings (COD/L) at same hydraulic retention time (HRT) and found that the initial substrate concentration of 4,000 mg COD/L is the best suited to achieve greater reactor performance. Between 114 and 245 d, by varying the HRT from 30 to 3 h, the biogas production rate increased with decrease in HRT. In this study, the mathematical models viz., modified Stover-Kincannon and Van der Meer and Heertjes models were applied to determine the gas production kinetics. [ABSTRACT FROM AUTHOR]

Thorium is a fertile element that can be applied in the conceptual blanket design of a fusion-fission hybrid reactor. It is essential to validate 232 Th nuclear data and obtain the breeding properties of macroscopic thorium assemblies by conducting integral neutronics benchmark experiments. The thorium assemblies with a D-T fusion neutron source consist of a polyethylene shell, depleted uranium shell, and thorium oxide powder cylinder. The 232 Th (n, γ), 232 Th (n, f), and 232 Th (n, 2n) reaction rates in the assemblies are measured by ThO 2 foil activation technique. The experimental uncertainties are about 3.1% for 232 Th capture rates, 5.3–5.5% for 232 Th fission rates, and 6.8–7.0% for 232 Th (n, 2n) reaction rates. From 232 Th reaction rates, the fuel and neutron breeding properties of thorium under different neutron spectra are obtained and compared. The experiments are simulated by using the MC code with different evaluated data. The ratios of calculation to experimental values for the reaction rates are analyzed. [ABSTRACT FROM AUTHOR]

The performance of the fusion–fission hybrid system based on the molten salt (flibe) blanket, driven by a plasma based fusion device, was analyzed by comparing transmutation scenarios of actinides extracted from the LWR (Sweden) and RBMK (Lithuania) spent nuclear fuel in the scope of the EURATOM project BRILLIANT. The IAEA nuclear fuel cycle simulation system (NFCSS) has been applied for the estimation of the approximate amount of heavy metals of the spent nuclear fuel in Sweden reactors and the SCALE 6 code package has been used for the determination of the RBMK-1500 spent nuclear fuel composition. The total amount of trans-uranium elements has been estimated in both countries by 2015. Major parameters of the hybrid system performance (e.g., k scr , k eff , Φ n ( E ), equilibrium conditions, etc.) have been investigated for LWR and RBMK trans-uranium transmutation cases. Detailed burn-up calculations with continuous feeding to replenish the incinerated trans-uranium material and partial treatment of fission products were done using the Monteburns (MCNP + ORIGEN) code system. About 1.1 tons of spent fuel trans-uranium elements could be burned annually with an output of the 3 GW th fission power, but the equilibrium stage is reached differently depending on the initial trans-uranium composition. The radiotoxicity of the remaining LWR and RBMK transmuted waste after the hybrid system operation time has been estimated. [ABSTRACT FROM AUTHOR]

A dielectric barrier discharge (DBD) catalyst hybrid reactor with CeO 2 /γ-Al 2 O 3 catalyst balls was investigated for benzene decomposition at atmospheric pressure and 30 °C. At an energy density of 37–40 J/L, benzene decomposition was as high as 92.5% when using the hybrid reactor with 5.0wt%CeO 2 /γ-Al 2 O 3 ; while it was 10%–20% when using a normal DBD reactor without a catalyst. Benzene decomposition using the hybrid reactor was almost the same as that using an O 3 catalyst reactor with the same CeO 2 /γ-Al 2 O 3 catalyst, indicating that O 3 plays a key role in the benzene decomposition. Fourier transform infrared spectroscopy analysis showed that O 3 adsorption on CeO 2 /γ-Al 2 O 3 promotes the production of adsorbed O 2 − and O 2 2‒ , which contribute benzene decomposition over heterogeneous catalysts. Nano particles as by-products (phenol and 1,4-benzoquinone) from benzene decomposition can be significantly reduced using the CeO 2 /γ-Al 2 O 3 catalyst. H 2 O inhibits benzene decomposition; however, it improves CO 2 selectivity. The deactivated CeO 2 /γ-Al 2 O 3 catalyst can be regenerated by performing discharges at 100 °C and 192–204 J/L. The decomposition mechanism of benzene over CeO 2 /γ-Al 2 O 3 catalyst was proposed. [ABSTRACT FROM AUTHOR]

Fusion-fission hybrid reactor takes advantage of the best of both domains, fusion and fission, without needing a full development of fusion reactor, and without critical safety issues of fission reactor. However, decay heat still exists in fission blanket of hybrid rector in shutdown state, which will menace the safety of rector if it cannot be smoothly carried out. To testify the passive safety characteristics of fission blanket, the reactor coolant pump shaft seizure accident in fission blanket of FFHER, a fusion-fission hybrid reactor, is simulated. The model of passive residual heat removal system, as well as reactor coolant system, are built using software SCDAP/RELAP5 4.0. The analysis shows that the simulated system response is reasonable. In the SG domination stage, the peak fuel temperature keeps always below the limiting value. In the PRHR domination stage, three cases are simulated and compared to choose appropriate parameter. It is found that PRHR circulation can be rapidly established and transfer enough heat from blanket. The transition from SG domination to PRHR domination is smooth. From the simulation results, it can be concluded that PRHRS can provide sufficient blanket cooling capability in LOFA. [ABSTRACT FROM AUTHOR]

In this paper, an integrated fusion-fission hybrid reactor energy system aiming at utilizing the thorium fuel efficiently with Th-U closed cycle is presented. The ultimate purpose is transition to the all thorium fueled energy system with the bred 233 U fuel burning in-site. The system consists of two fusion-fission hybrid reactors. The first reactor is a fast breeder which provides the starting fuel 233 U for the second reactor (thermal burner). The bred 233 U is burnt in the second reactor with the thorium bearing molten salt fuel blanket. In order to reach the multi-system performance, i.e. high energy multiplication M, tritium self-sufficiency and fissile fuel self-sufficiency, using limiting 233 U start fuel, the seed-blanket concept is adopted in the thermal burner design. The thermal burner blanket is divided into two main regions. The front region (seed) plays the dominate role in the energy production, neutron multiplication and 233 U breeding. Excess neutrons produced by the front region are then used to drive backward region (blanket) to breed tritium. The Couple 2.0 code developed by Tsinghua University is used to calculate the fuel depletion process of the whole system. The simulated results show, the thermal burner could operate with excellent performance, energy multiplication M (8–10), tritium breeding ratio TBR (>1.05) continuously and only natural thorium fuel is added into the system. [ABSTRACT FROM AUTHOR]

A statistical model description of heavy ion induced fusion–fission reactions is presented where shell effects, collective enhancement of level density, tilting away effect of compound nuclear spin and dissipation are included. It is shown that the inclusion of all these effects provides a consistent picture of fission where fission hindrance is required to explain the experimental values of both pre-scission neutron multiplicities and evaporation residue cross-sections in contrast to some of the earlier works where a fission hindrance is required for pre-scission neutrons but a fission enhancement for evaporation residue cross-sections. [ABSTRACT FROM AUTHOR]

This study investigated the biodegradability of composting leachate and biogas production in different Organic Loading Rates (OLRs) in lab-scale series AMBR-ASBR bioreactors, Anaerobic Migrating Blanket Reactor (AMBR) and Anaerobic Sequencing Batch Reactor (ASBR). The raw Leachate with OLRs of 1.04–19.65 gCOD/L.d went into the AMBR reactor and then into the ASBR reactor with hydraulic retention time of 24 h. The produced methane and biogas were measured by GC-TCD and gas meter. The results showed that the best removal efficiency for BOD 5 , COD and readily biodegradable COD (rbCOD) in AMBR-ASBR hybrid reactor were 99.43%, 97.35% and 99.79%, respectively. The maximum amounts of biogas and methane production were 16.37 and 9.99 L in OLR of 10.08 gCOD/L.d. With the increase in OLRs, biogas production also increased, but in higher OLRs (18.52 gCOD/L.d) with a sudden increase in OLR, methane and biogas production decreased. Moreover, the ratio of the biogas production to inlet COD was 1.35 L (R 2 = 0.994), that is equal to the ratio of produced biogas (L) to inlet Volatile Suspended Solids (VSS) (g) (R 2 = 0.972). Thus, considering OLRs effects, it was observed that the AMBR-ASBR hybrid reactor as a novel series system could be remarkably efficient in compost leachate treatment and increasing biogas production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Water & Land Development is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New data on biogas production and treatment of cattle wastewater were registered using an upflow anaerobic sludge blanket-anaerobic filter (UASB-AF) hybrid reactor under mesophilic temperature conditions (37 °C). The reactor was operated in semi-continuous mode with hydraulic retention times of 6, 5, 3 and 2 days and organic loading rates of 3.8, 4.6, 7.0 and 10.8 kg CODt m-3 d-1. Biogas volumes of 0.6-0.8 m³ m-3 d-1 (3.8-4.6 kg CODt m-3 d-1) and 1.2-1.4 m³ m-3 d-1 (7.0-10.8 kg CODt m-3 d-1), with methane concentrations between 69 and 75%, were attained. The removal of organic matter with values of 60-81% (CODt) and 51-75% (CODs) allowed methane yields of 0.155-0.183 m³CH4 kg-1 CODt and 0.401-0.513 m³ CH4 kg-1 CODs to be obtained. Volatile solids were removed in 34 to 69%, with corresponding methane yields of 0.27 to 0.42 m³ CH4 kg-1 VSremoved. The good performance of the novel hybrid reactor was demonstrated by biogas outputs higher than reported previously in the literature, along with the quality of the gas obtained in the various experimental phases. The hybrid reactor investigated in this study presents comparative advantages, particularly in relation to conventional complete mixture units, considering economic factors such as energy consumption, reactor volume and installation area. [ABSTRACT FROM AUTHOR]

This work aims at constructing a design which integrates a direct (solid) contact method with temperature control for chemical process applications. To realise this integration a two-step approach is proposed. Firstly, temperature control is achieved by suspending the tubing in a temperature controlled and sonicated liquid medium (indirect contact). Secondly, direct contact elements are introduced at regular intervals along the tubing. Therefore, this design is termed the hybrid contact reactor, as it incorporates both direct and indirect approaches of ultrasound transfer. Furthermore, two possible configurations, open and closed interval connection to the tubing, were assessed. Both hybrid reactors performed better than the indirect contact reactor (20–27% increase in yield) for residence times of less than 45 s and similar for residence times above. Even though the performance of the two hybrid designs was similar the closed interval resulted in more reproducible and distinct yields. This configuration was then scaled up 10 times in internal volume using a 2 mm ID tube. This design showed a relative performance similar to the interval contact design which gave the highest yields thus far for the same operating conditions. [ABSTRACT FROM AUTHOR]

Aiming at validating thorium fission parameters and the code used in the conceptual design of fusion-fission hybrid energy reactor, an integral experiment on thorium oxide/depleted uranium cylinder assemblies for thorium fission rate has been carried out with D-T neutrons. Thorium fission rate in the axial direction of the assemblies was obtained by adopting the activation method, and the experimental uncertainties were 5.6–5.9%. MCNP simulation employing ENDF/B-VII.0 and ENDF/B-VII.1 library data were 5%–21% smaller than experimental ones. The influence of the polyethylene oxide (PEO) in the thorium oxide cylinders, evaluated by MCNP simulation employing ENDF/B-VII.0 library data, is negligible in the present thorium/uranium assemblies under the measured level. The difference between the present results and our previous ones was also analyzed. The stage experimental results could provide reference for the evaluation of neutron-induced thorium fission cross section, and should be considered in the margin of the conceptual design of FFHER. [ABSTRACT FROM AUTHOR]

A hybrid fission-fusion reactor with a Dense Plasma Focus (DPF) as a fusion core and the dual layer fissionable blanket as the energy multiplier were conceptually designed. A cylindrical DPF, energized by a 200 kJ bank energy, is considered to produce fusion neutron, and these neutrons drive the subcritical fission in the surrounding blankets. The emphasis has been placed on the safety and energy production with considering technical and economical limitations. Therefore, the k eff-t of the dual cylindrical blanket was defined and mathematically, specified. By applying the safety criterion ( k eff-t ≤ 0.95), the geometrical and material parameters of the blanket optimizing the energy amplification were obtained. Finally, MCNPX code has been used to determine the detailed dimensions of the blankets and fuel rods. [ABSTRACT FROM AUTHOR]

Hybrid reactor of Dielectric Barrier Discharge (DBD) and Solid Oxide Electrolyser Cell (SOEC) was fabricated and CO2 decomposition characteristics were investigated. For the case of the DBD reactor alone, the CO2 conversion saturates with residence time. In contrast, the saturation is not observed for the case of the hybrid system where CO2 conversion increases monotonically with increasing residence time. This is because the reverse reaction to regenerate the CO2 in plasma is suppressed by the oxygen removal by SOEC in hybrid system and consequently CO2 decomposition reaction proceeds irreversibly. We have examined the experimental results by analytical modeling and reaction mechanism for the CO2 decomposition in the hybrid reactor of DBD and SOEC is deduced. The time-dependent CO2 conversion for the only plasma reactor and hybrid reactor can be reproduced by a reversible and irreversible first-order reaction model, respectively. The analytical model can also reproduce the dependence of CO2 conversion on the plasma input power very well. Interestingly, not only the reverse reaction rate but also the forward dissociation reaction rate is reduced by the SOEC in the case of hybrid reactor. The analytical modeling suggests that CO2 decomposition in the conventional DBD plasma reactor proceeds not merely by direct electron impact dissociation but also by reaction with reactive oxygen. [ABSTRACT FROM AUTHOR]

The present study deals with development of a hybrid reactor for biodiesel production based on the combined hydrodynamic cavitation and mechanical stirring processes. Biodiesel were produced using Kaner Seed Oil (KSO). The experimental results show that hybrid reactor produces 95% biodiesel yield within 45 min for 0.75% of catalyst and 6:1 M ratio which is significantly higher as compared to mechanical stirring or hydrodynamic cavitation alone. Thus biodiesel production process in hybrid reactor is cheap (high yield), efficient (time saving) and environmentally friendly (lower% of catalyst). Performance study on engine shows that an increase in compression ratios (from 16 to 18) improves the engine performance using biodiesel blends as compared to petroleum diesel. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD) is the most efficient way used in industry for ozone generation. In the last decades, many papers were published on such DBD-based ozone generators. Several geometric configurations can be used to generate ozone. They can be classified into two types depending on the discharge form: volume DBD, which is the common one in ozone industry, and surface DBD. Many studies have been conducted to analyze the ozone generation efficiency of both reactors to get maximum ozone production with the lowest possible power consumption. The aim of this paper is to carry out an experimental analysis of a patent-pending new reactor, of hybrid configuration, in which occur simultaneously a volume and a surface DBD. The hybrid reactor comprises a ground stainless steel cylindrical electrode, within which is placed a glass tube separated by an interval of 1 mm in which the volume DBD occurs. A second mesh stainless steel electrode connected to the high voltage is placed inside the glass tube wherein the surface discharge occurs. The obtained results showed a clear superiority of the hybrid reactor compared with both volume and surface DBD in terms of the ozone concentration. The difference in the ozone concentration reaches up to 50% compared with the volume DBD and 30% compared with the surface DBD. [ABSTRACT FROM PUBLISHER]

This study aimed to investigate potential methane production through anaerobic digestion of dairy manure and co-digestion with maize silage. Two different anaerobic reactor configurations (single-stage continuously stirred tank reactor [CSTR] and hybrid anaerobic digester) were used and biogas production performances for each reactor were compared. The HR was planned to enable phase separation in order to improve process stability and biogas production under higher total solids loadings (≥4%). The systems were tested under six different organic loading rates increased steadily from 1.1 to 5.4 g VS/L.d. The CSTR exhibited lower system stability and biomass conversion efficiency than the HR. The specific biogas production of the hybrid system was between 440 and 320 mL/gVS with 81-65% volatile solids (VS) destruction. The hybrid system provided 116% increase in specific biogas production and VS destruction improved by more than 14%. When MS was co-digested together with dairy manure, specific biogas production rates increased about 1.2-fold. Co-digestion was more beneficial than mono-material digestion. The hybrid system allowed for generating methane enriched biogas (>75% methane) by enabling phase separation in the reactor. It was observed that acidogenic conditions prevailed in the first two compartments and the following two segments as methanogenic conditions were observed. The pH of the acidogenic part ranged between 4.7 and 5.5 and the methanogenic part was between 6.8 and 7.2. [ABSTRACT FROM AUTHOR]

The fixed bed reactor was combined with a solar photoreactor and UV lamp reactor. This hybrid photoreactor used a heterogeneous photocatalysis process (TiO 2 /UV) as a tertiary treatment for the degradation of tartrazine dye in water. The solar reactor removed almost all organic compounds from the wastewater. Photocatalysis was optimized using a parametric study to improve the influence of different parameters on the degradation efficiency. Color removals when using solar, UV lamp and hybrid reactors present 99%, 30%, and 99%, respectively. Tartrazine removal kinetics followed a pseudo-first order model. The hybrid solar and UV lamp system combination was a feasibility choice for removing both dyes from wastewater. [ABSTRACT FROM AUTHOR]

The level of knowledge accumulated to date in the physics and technologies of controlled thermonuclear fusion (CTF) makes it possible to begin designing fusion-fission hybrid systems that would involve a fusion neutron source (FNS) and which would admit employment for the production of fissile materials and for the transmutation of spent nuclear fuel. Modern Russian strategies for CTF development plan the construction to 2023 of tokamak-based demonstration hybrid FNS for implementing steady-state plasma burning, testing hybrid blankets, and evolving nuclear technologies. Work on designing the DEMO-FNS facility is still in its infancy. The Efremov Institute began designing its magnet system and vacuum chamber, while the Kurchatov Institute developed plasma-physics design aspects and determined basic parameters of the facility. The major radius of the plasma in the DEMO-FNS facility is R = 2.75 m, while its minor radius is a = 1 m; the plasma elongation is k = 2. The fusion power is P = 40 MW. The toroidal magnetic field on the plasma-filament axis is B = 5 T. The plasma current is I = 5 MA. The application of superconductors in the magnet system permits drastically reducing the power consumed by its magnets but requires arranging a thick radiation shield between the plasma and magnet system. The central solenoid, toroidal-field coils, and poloidal-field coils are manufactured from, respectively, NbSn, NbTi and NbSn, and NbTi. The vacuum chamber is a double-wall vessel. The space between the walls manufactured from 316L austenitic steel is filled with an iron-water radiation shield (70% of stainless steel and 30% of water). [ABSTRACT FROM AUTHOR]