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The solar furnace is key equipment for the thermochemical reaction research which uses focused solar energy to drive the reactor, and the solar flux distribution on the reactor surface plays a decisive role in the regulation of the thermochemical reaction process and formation of target products. In this paper, a reflective solar furnace with a thermal power of 30 kWth in Yanqing, Beijing, is taken as the research objective. Firstly, the Monte Carlo Ray Tracing (MCRT) method is used to establish the mathematical model for the optical calculation, and the distribution characteristics of solar flux are deeply analyzed. The accuracy of the model is verified through the comparison with the SolTrace software and experimental measurements respectively. Secondly, an improved four-quadrant and adjustable focusing solar furnace experimental equipment is developed, and a new solar flux distribution regulation strategy is proposed by using the inward crossover and outward expansion offset of the four-quadrant focusing points coupled with the heat-absorbing platform movement. The results show that the non-uniform factor and the peak value of the solar flux distribution in the set target area can be optimized by selecting an appropriate inward crossover offset and movement of the heat-absorbing platform, respectively. Moreover, when the DNI varies between 480 W/m2 and 800 W/m2, through the optimized control strategy, a non-uniformity factor with the value of less than 0.10 can be achieved in the target area of a square reactor surface with a side length of 10 cm, and the peak flux can also be controlled in the range from 3000 kW/m2 to 3300 kW/m2 with a fluctuation range of less than 10.0% as set by the thermochemical reaction. The optimized control strategy can effectively meet the uniformity and stability requirements of solar flux distribution in solar thermochemical reaction and finally achieve the goal of regulating the target products. • An improved four-quadrant adjustable focusing solar furnace is developed. • An innovative solar flux distribution regulation strategy is proposed. • A non-uniformity factor with the value of less than 0.10 can be achieved. • The peak flux can be controlled in the range from 3000 kW/m2 to 3300 kW/m2. [ABSTRACT FROM AUTHOR]

Thermal plasma reactors offer an environment of high temperature, enthalpy, and reactivity, making them highly efficient for solid waste treatment and promising for clean energy production from municipal and industrial waste. Optimal geometrical parameters of the reactor can enhance waste treatment and reactor performance. This study presents a comprehensive analysis of 11 key geometrical parameters of a thermal plasma reactor. Utilizing CFD Fluent software, numerical simulations were conducted to generate a dataset. Subsequently, a predictive model focusing on the average temperature in the core melt zone was trained using six Machine Learning (ML) algorithms. The Particle Swarm Optimisation (PSO) algorithm optimized the hyperparameters of the Gradient Booster Regression (GBR) model, which was combined with a Genetic Algorithm (GA) to identify the reactor's optimal geometrical parameters. A DC arc plasma torch-solid waste thermal plasma reactor treatment system was established on this basis. The study also explored the effects of gasification coefficient, reaction temperature, and thermal plasma jet mode on system performance. Findings indicate that the PSO-GBR model achieved the highest prediction accuracy, with the temperature in the core reaction zone reaching 3621 K. The deviation between numerical simulations and machine learning predictions was a mere 1.3%. Enhancing syngas yield and energy efficiency is achievable by controlling reaction temperature and increasing the gasification coefficient. A laminar plasma jet mode, at equal power, provides a more effective reaction environment. The accuracy and reliability of the machine learning-driven regression model and optimization results are significant in guiding the optimal design of plasma reactors and advancing waste-to-energy conversion processes. [Display omitted] • Study integrates CFD and ML to predict optimal structural parameters of a thermal plasma reactor. • GBR optimized by PSO was most effective in predicting the reactor core's average temperature. • The theoretical predictions of the CFD-ML framework are validated based on an experimental setup. • Study examines reactor performance under varying conditions, offering insights for waste-to-energy conversion. [ABSTRACT FROM AUTHOR]

Chemical looping combustion (CLC) is a promising CO 2 capture technology, which expected to achieve 100% capture efficiency with a low energy penalty. The principle of CLC is utilizing an oxygen carrier as a medium for transporting oxygen between two reactors, aiming to avoid nitrogen in combustion exhaust. This article discusses the advances in chemical looping with a focus on oxygen carriers, reactors, coupling systems, and other applications of CLC concept for solid fuels. The development and design of high performance oxygen carriers and suitable reactors are key factors in the development of CLC technology. The main challenge in scaling up the CLC process is the development of appropriate OCs with optimal properties, including high transport oxygen capacity, reactivity, and stability. Recently, a fair number of hours of continuous operation in pilot plants have instilled the confidence required in further development of this process towards commercialization. The use of solid fuels is gaining momentum, and the liquid fuels need further attention for its development. The integrated systems based on chemical looping technology for poly-generation applications simultaneously achieve the efficient conversion and cascade utilization of chemical energy and CO 2 separation. The article also describes the prospects of the future development in the chemical looping technology, and its viability for industrial deployment. [Display omitted] • CLC is a well-known technology for reducing the energy penalty of CO 2 capture. • Both oxygen carrier properties and reactor design are key to CLC development. • Various types of reactors used for chemical looping conversion have been summarized. • Different integrated systems based on chemical looping technology are discussed. • Different chemical looping technologies for combustion of solid fuels are considered. [ABSTRACT FROM AUTHOR]

Currently, biofuels represent a solution for the European Union in the transportation sector in order to reduce the greenhouse gas (GHG) emissions and the dependency of fossil fuels. Biodiesel from vegetable oils is a solution for countries with low GDP per capita to strengthen the internal agriculture, provide jobs, and reduce the use of fossil fuels. In this study, we model and simulate a temperature regulator designed for the biodiesel transesterification process in a discontinuous batch reactor, using methanol and a homogenous basic catalyst. The simulation was based on the kinetical model of the transesterification reaction and the mathematical model of the reactor. We considered molar ratios of alcohol/oil of 6:1 and 9:1, respectively, to shift the reaction equilibrium towards the production of fatty acid methyl esters. In the design of the simulation, the methanol boiling point was considered a restriction, therefore, temperatures below 65 °C were imposed. The results demonstrate that the increase in temperature results in a decrease in the reaction time and a higher yield, especially for the 6:1 molar ratio reaction, and that the optimum temperature for the batch reactor is of 60 °C. Automatic control improves the performance and costs of production.

In this study, three anaerobic digestion reactors using up‐flow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (AnSBR), and anaerobic membrane bioreactor (AnMBR) were studied. The chemical oxygen demand (COD), gas production, sludge performance, and microbial characteristics of the anaerobic digestion process were assessed. The results showed that the average COD removal efficiencies reached 86%, 83%, and 85%, with corresponding removed rates of 2.49, 0.48, and 0.79 kg COD m−3 d−1 in UASB, AnSBR, and AnMBR, respectively. After the reactors attained stable operation, both extracellular polymeric substances and soluble microbial products decreased in all the reactors compared with the seed sludge. Methanothrix was the dominant archaea for methane production in the UASB, the relative abundance of which increased from 58.3% to 83.4%. These results identify UASB as the most suitable reactor for anaerobic digestion when treating wastewater with low carbon. Such reactors are important for the application and development of the energy self‐sufficiency in sewage treatment. Practitioner Points: UASB, SBR, and MBR were adopted to treat low‐carbon wastewater using anaerobic digestion process.UASB performed the highest COD removal from low‐carbon wastewater.The main microorganisms in UASB were Methanothrix, Methanomassiliicoccus, and Methanobacterium. [ABSTRACT FROM AUTHOR]

Most animal models of infection utilize planktonic bacteria as initial inocula. However, this may not accurately mimic scenarios where bacteria in the biofilm phenotype contaminate a site at the point of injury. We developed a modified CDC biofilm reactor in which biofilms can be grown on the surface of simulated fracture fixation plates. Multiple reactor runs were performed and demonstrated that monomicrobial biofilms of a clinical strain of methicillin-resistant Staphylococcus aureus, S. aureus ATCC 6538, and Pseudomonas aeruginosa ATCC 27853 consistently developed on fixation plates. We also identified a method by which to successfully grow polymicrobial biofilms of S. aureus ATCC 6538 and P. aeruginosa ATCC 27853 on fixation plates. This customized reactor can be used to grow biofilms on simulated fracture fixation plates that can be inoculated in animal models of biofilm implant-related infection that, for example, mimic open fracture scenarios. The reactor provides a method for growing biofilms that can be used as initial inocula and potentially improve the testing and development of antibiofilm technologies. [ABSTRACT FROM AUTHOR]

Hydrogen is increasingly being viewed as a significant fuel for future industrial processes as it offers pathways to zero emission. The UK sees hydrogen as one of a handful of low-carbon solutions for transition to net zero. Currently, most hydrogen production is from steam reforming of natural gas or coal gasification, both of which involve the release of carbon dioxide. Hydrogen production from mini decentralised grids via a thermochemical process, coupled with electricity production, could offer favourable economics for small modular reactors (SMRs), whereby demand or grid management as a solution would include redirecting the power for hydrogen production when electricity demand is low. It also offers a clean-energy alternative to the aforementioned means. SMRs could offer favourable economics due to their flexible power system as part of the dual-output function. This study objective is to investigate the critical performance parameters associated with the nuclear power plant (NPP), the cycle working fluids, and control-system design for switching between electricity and hydrogen demand to support delivery as part of a mini grid system for a reactor power delivering up to approximately 600 MWth power. The novelty of the work is in the holistic parametric analysis undertaken using a novel in-house tool, which analyses the NPP using different working fluids, with a control function bolt-on at the offtake for hydrogen production. The results indicate that the flow conditions at the offtake can be maintained. The choice of working fluids affects the pressure component. However, the recuperator and heat-exchanger effectiveness are considered as efficiency-limiting factors for hydrogen production and electricity generation. As such, the benefit of high-technology heat exchangers cannot be underestimated. This is also true when deciding on the thermochemical process to bolt onto the plant. The temperature of the gas at the end of the pipeline should also be considered to ensure that the minimum temperature-requirement status for hydrogen production is met. [ABSTRACT FROM AUTHOR]

A scheme of a gas–liquid mixed jet is designed by installing gas distributor at the bottom of a stirred tank reactor to generate Taylor vortex. The eddy flow characteristics and mass transfer mechanism in the reactor are analyzed by numerical simulation and experiment. The results show that the evolution law of Taylor vortex in a stirred tank reactor with a rotating Reynolds number is similar to that in a conventional Taylor reactor. The Taylor vortex generated in the stirred tank reactor creates a partial plug flow region in the original complete mixing flow pattern, which reduces back mixing, the plug flow area expands with the increase of rotating Reynolds number. Under the condition of a critical rotating Reynolds number (Recr), the gas phase homogeneity of the reactor is increased by 28% and the dissolved oxygen rate is increased by about 5 times, which effectively improves the flow condition in the reactor and strengthens the mass transfer efficiency between the gas and liquid. The research results provide a theoretical basis for breaking through the limitation of small reaction space of conventional Taylor flow reactor and expanding production scale. The refit of kettle reactor is universal and easy to operate. [ABSTRACT FROM AUTHOR]

In this work, the photodegradation of methylene blue was investigated by constructing a novel photocatalysis reactor, which was filled with aqueous foam. Nanoscale TiO2 particles were used as photocatalyst. In order to obtain stable foam phase, cetyl trimethyl ammonium bromide (CTAB) was used as the frother, and its suitable initial concentration in the feeding solution was 0.20 g/L. Under the suitable conditions of loading liquid volume 200 mL, initial concentration of TiO2 nano-catalysts in the feeding solution 5.0 g/L, inner diameter of foam column 18 mm, aperture diameter of gas distributor 125 μm, and circulating velocity of bulk solution 500 mL/h, the maximum degradation percentage of methylene blue was 97.6 ± 1.2%. Atomic force microscopy (AFM) analysis suggested that the entrainment effect of rising bubbles and the circulation flow of bulk solution inside the aqueous foam did not cause the conspicuous aggregation of TiO2 nano-catalysts under the suitable conditions, but their surface roughness decreased. Meanwhile, foam entrainment had not a significant impact on the polydispersity of TiO2 nano-catalysts. In contrast to the photodegradation of methylene blue in aqueous solution, the photocatalysis process using aqueous foam is the intensity of light received by TiO2 nano-catalyst increases, and irradiation period is less. This work is expected to provide new insight into the rational design of photocatalysis reactor, to facilitate the harmless treatment of dyestuff wastewater. [ABSTRACT FROM AUTHOR]

Neutron moderators, such as nuclear-grade graphite, are essential components of high-temperature nuclear reactors. Their primary functions are to degrade the energy of fission-born neutrons into an energy range that promotes further fission and to serve as the central core structure. This paper will discuss historic reactor moderator materials, which are relatively simple monolithic materials each having intrinsic benefits and limitations. Additionally, a new class of engineered composite moderators is presented for which two examples are fabricated: magnesia-matrix composite systems with either beryllium-based or metal-hydride entrained phases. In additions to presenting their route to fabrication effectiveness as advanced moderators is discussed. [ABSTRACT FROM AUTHOR]

A transferred arc plasma torch chemical rector was used to process waste formed from mixtures of dry clay powder and hydroquinone. Such reactors are best suited for the treatment of electrically conductive waste. In these types of reactors, the electric arc moves chaotically throughout the entire reactor volume, making it possible to ensure an even temperature distribution in the reaction zones. An analysis of the literature has shown that there are not many study results related to this type of reactor. The novelty of the work is that the behavior of the operating electric arc inside the reactor was recorded by using a high-speed camera. The distribution of the temperature profile at the cooled reactor wall was investigated. The electrical potential difference inside the reactor was also investigated. To better understand the behavioral properties of the electric arc when the reactor is filled with treated material, hydroquinone-contaminated clay was used. In this case, the movement of the electric arc, as well as the probability of its formation, is the greatest at the location where the thinnest layer of the material to be processed is located. In addition, it has been observed that the use of a graphite anode poses problems because, over time, the anode of such a design deforms due to interactions with the electric arc. While analyzing research results, it can be observed that these types of reactors are very suitable for the treatment of electrically conductive materials and for the treatment of small amounts of nonconductive materials when the material occupies a relatively small part of the reactor. A further development of these studies in the future is planned in order to make the reactors as versatile as possible and as suitable as possible for handling the widest range of materials possible. [ABSTRACT FROM AUTHOR]

To develop the latest energy-saving technologies, it is necessary to use effective and affordable thermal insulation materials. For a long time, and most importantly with great success, materials made from rock melts – basalts – have been used abroad. Basalt is the most acceptable raw material for producing environmentally friendly and most importantly inexpensive products. In Russia, there is an increasing interest in products based on basalt fiber, due to the rapid development of construction. At the moment, more than 300 deposits of basalt rocks have been discovered on the territory of Russia. And in the strategy of socio-economic development of the North Caucasus Federal district until 2025, the production of building materials from basalt is designated as a priority industry. However, there are also a number of problems that hinder the development of production capacities for processing igneous rocks into continuous basalt fiber, such as maintaining a constant temperature.

Understanding of extreme weather conditions at the site of interest is essentially required in the design of engineering structures so that the structures can withstand weather stresses. This paper presents an analysis of extreme values of meteorological elements observed at Narora site for the last three decades (1989–2019). The elements considered are extreme air temperature (°C), minimum relative humidity (%), extreme wind gust (km/h), maximum rainfall (mm) in a day and a month, and annual rainfall. The extreme value analysis reveals that the maximum air temperature, maximum wind gust at 30 m, maximum monthly rainfall, and maximum annual rainfall obey Fisher-Tippett Type-1/Gumbel extreme value distribution, whereas minimum air temperature, minimum relative humidity (%), annual daily maximum rainfall (mm), and annual minimum rainfall (mm) obey Fisher-Tippett Type-2/Frechet extreme value distribution function. Distribution function parameters, i.e., location, scale, and shape parameter for each variable, have been determined. Extreme values corresponding to return periods of 50, 100, and 1000 years are worked out using best fit linear regression curve as a compliance of the Atomic Energy Regulatory Board Safety Guide Recommendations. The derived extreme values are particularly useful to designer for arriving at suitable design basis values of different elements to ensure the safety of the reactors and other civil structures in Narora region, with respect to stresses due to weather conditions. Extreme values corresponding to return periods of 50 and 100 years at Narora are compared with corresponding values at other three nuclear reactor sites in India, namely, Tarapur, Kalpakkam, and Trombay. In addition, the time series pattern analysis of rainfall for 31 years at the Narora site closely following the 2-year moving average rainfall data pattern. These results can be used for water harvesting, irrigation, and floods management plans in the future.

Telecommunications companies in Nigeria have formulated policies that could enable them to cope with the global challenges. However, most of them have not really employed strategic options that could enable them to cope with the changing condition. The main objective of this study is to examine the effect of Miles and Snows strategies which is considered the major approach that could promote competitiveness in the industry to enable them manage and survive challenges. The study adopted survey research design and population is 7,567 staff of four major service providers MTN, Airtel, Globacom and 9Mobile with sample size of 380. Judgemental and stratified random sampling techniques were used to select participants for the study. Out of the 380 distributed questionnaires, 369 were retrieved. The study reaffirmed the efficacy of Mile and Snow’s competitive strategy. It was recommended that Telecom Company should adopt prospector, analyzer, and defender strategies to improve their performances.

The new design of the photocatalytic reactor is crucial to study for improving compatibility and scaling up the operation. A compatible loop photocatalytic reactor has been designed and used for rhodamine B decomposition. The photocatalysts were either ZnO or Fe-ZnO immobilized onto fiberglass cloth. The ZnO catalyst exhibited high crystallinity with or without Fe as the dopant. The crystallite size increased with the presence of Fe in the lattices. Most of the crystal parameters matched the standard ZnO data, and the cluster size was comparable to most reported studies. Diffuse Reflectance Spectroscopy (DRS) analysis confirmed the photon absorption shifted to the visible light range. The Fe dopant decreased the ZnO bandgap, and SEM-EDS confirmed the catalysts adhered to the fiberglass surface. The volume, thickness of the substrate solution, and reaction temperature influenced the photocatalytic-degradation rate. The photocatalytic degradation rate was higher under sunlight than ultraviolet irradiation. The reaction rate was lower in the batch reactor than in the loop reactor. The photocatalytic reaction almost completely mineralized RhB and changed the red solution to colorless. The immobilized photocatalyst has been reused more than 50 times without significantly decreasing the catalytic activity.

This work describes the design, construction, and evaluation of a sequential discontinuous reactor with recirculation and aeration through a Herschel-type Venturi tube made of high-density polyethylene, coupled to a centrifugal pump. Four laboratory-scale prototypes were built, each with a volume of 8 L and a characteristic distance for venturi discharge. During the evaluation, temperature, pH, and dissolved oxygen were monitored. Also, the chemical oxygen demand (COD), the biological oxygen demand (BOD5), and the total suspended solids (TSS) in the clarified discharge liquid were determined. The BOD5 reduction efficiency registered values higher than 80%, while the COD reduction efficiency was around 60%. Thus, the action of microorganisms reduced the biodegradability factor, the BOD5, and contributed to the DQO through soluble microbial products. Besides, the increase of solids retention time (SRT) evidenced the increase in biomass settleability, which positively contributed to SBR operation. The results obtained support the implementation of the sequential batch reactor with mixing and aeration by recirculation through a Venturi as a technology for wastewater treatment.

The Daya Bay experiment was the first to report simultaneous measurements of reactor antineutrinos at multiple baselines leading to the discovery of ν¯e oscillations over km-baselines. Subsequent data has provided the world's most precise measurement of sin22θ13 and the effective mass splitting Δmee2. The experiment is located in Daya Bay, China where the cluster of six nuclear reactors is among the world's most prolific sources of electron antineutrinos. Multiple antineutrino detectors are deployed in three underground water pools at different distances from the reactor cores to search for deviations in the antineutrino rate and energy spectrum due to neutrino mixing. Instrumented with photomultiplier tubes, the water pools serve as shielding against natural radioactivity from the surrounding rock and provide efficient muon tagging. Arrays of resistive plate chambers over the top of each pool provide additional muon detection. The antineutrino detectors were specifically designed for measurements of the antineutrino flux with minimal systematic uncertainty. Relative detector efficiencies between the near and far detectors are known to better than 0.2%. With the unblinding of the final two detectors' baselines and target masses, a complete description and comparison of the eight antineutrino detectors can now be presented. This paper describes the Daya Bay detector systems, consisting of eight antineutrino detectors in three instrumented water pools in three underground halls, and their operation through the first year of eight detector data-taking.

The dc reactor is an important part of the Comprehensive Research Facility for Fusion Technology (CRAFT), which can improve the current quality and reduce the probability of faults. In this article, several common inductance calculation methods are compared, and the more effective row mutual inductance method is selected as the final calculation method of the dc reactor. Using the existing conductor size, the electromagnetic design of the reactor is carried out, and the structural size is determined. The finite-element method (FEM) is used to verify the correctness of the calculation. On the premise of the completion of the electromagnetic structure, to ensure that the temperature rise during the operation of the equipment meets the requirements, a cooling system is needed. The structure and parameters of the waterway are determined by formula calculation, and FEM is used to verify the data. This article provides a preliminary scheme for the related reactor. [ABSTRACT FROM AUTHOR]

This paper describes the regeneration mechanism of electrochemical regeneration technology, and emphatically introduces the effects of current density, regeneration time, electrolyte, electrolyte mass concentration, pH value and regeneration position on GAC regeneration efficiency, and the reactor for electrochemical regeneration of GAC. Finally, the development trend of electrochemical regeneration method is discussed, and it is pointed out that optimizing mechanism, developing other technologies based on electricity, and exploring the combination of electrochemistry and other technologies are the future research focuses of electrochemical regeneration of granular activated carbon. [ABSTRACT FROM AUTHOR]

Soil contaminated with hydrophobic organic hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), pose a serious threat to the ecosystem and human health. Moreover, the sorption and desorption of the PAHs, due to the interaction with the soil organic matter (SOM) and other contaminants, greatly affect the fate and mycoremediation efficiency of the contaminated soil. On the other hand, the application of surfactants with or without additives for the mobilization of PAHs from contaminated soil has garnered increasing attention for soil remediation. In this context, several commercial surfactants and biosurfactants were reported either as soil flushing agents or soil additives, followed by either in situ or ex situ mycoremediation of the PAHs from contaminated soil. Hence, for a successful implementation of surfactants for mycoremediation of contaminated soil, a comprehensive introspection on its chemistry and mechanism is necessary. Thus, this review focuses primarily on understanding the effect of surfactants and the mechanism of desorption of PAHs from the soil. This work also emphasizes the effect of surfactants on the efficiency of mycoremediation of contaminated soil. Further, the review summarizes various surfactant‐assisted mycoremediation strategies of contaminated soil. Finally, the limitations of surfactant‐assisted mycoremediation, precipitative, and partitioning loss, along with toxicity of the surfactants, were reviewed. Thus, this review will aid in understanding the underlying mechanism and efficiency of surfactant‐assisted mycoremediation and it also proposes current research trends to improve the efficiency and enhance the bioremediation of PAHs‐contaminated soil. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

A nonlinear boundary value problem is considered that describes the operation of a flow-through biochemical reactor with allowance for the relaxation of the substance flow. A logistic law is adopted as the source of the substance. Nontrivial solutions are sought under homogeneous boundary conditions. The analysis is based on the limiting form of the equations of the relaxation model (RM). The change of operating modes of reactors is analyzed in the presence of two solutions of the equations of the process. [ABSTRACT FROM AUTHOR]

Coupling the hydrodynamic and biokinetic models, was done on a lab‐scale oxidation ditch as the bioreactor of the activated sludge process and validated against the available experimental data. The simulation was carried out in three‐phase, three‐dimensional conditions with k‐є and Eulerian–Eulerian methods. A simplified activated sludge model No.1 (ASM1) has been added to transport terms to account for the biokinetic model. Rotatory speed for surface aerator was initially increased and its corresponding effects on solid volume fraction, dissolved oxygen, and velocity profile and values were observed. A 150 rpm increase in the rotational velocity resulted in 36% higher average liquid phase velocity for the one‐aerator arrangement, which was 3% more than that of the two‐aerator oxidation ditch. The 150% increase in the solid volume fraction led to a 10% reduction in the maximum liquid phase velocity. The effect of aerators number has been considered explicitly on baffle performance and liquid phase velocity profile. Finally, a new design for the aerator has been offered that provides an ordered flow field and optimal conditions for the performance of the baffle and oxidation process. [ABSTRACT FROM AUTHOR]

Background: Caprine tuberculosis (TB) is a zoonosis caused by members of the Mycobacterium tuberculosis complex (MTBC). Caprine TB control and eradication programmes have traditionally been based on intradermal tuberculin tests and slaughterhouse surveillance. However, this strategy has limitations in terms of sensitivity and specificity. Different factors may affect the performance of the TB diagnostic tests used in goats and, subsequently, the detection of TB-infected animals. In the present study, the effect of two of the factors that may affect the performance of the techniques used to diagnose TB in goats, the topical administration of corticosteroids and a recent pre-sensitisation with tuberculin, was analysed. Methods: The animals (n = 151) were distributed into three groups: (1) a group topically treated with corticosteroids 48 h after intradermal tuberculin tests (n = 53); (2) a group pre-sensitised with bovine and avian purified protein derivatives (PPDs) 3 days before the intradermal tuberculin test used for TB diagnosis (n = 48); and (3) a control group (n = 50). All the animals were tested using single and comparative intradermal tuberculin (SIT and CIT, respectively) tests, an interferon-gamma release assay (IGRA) and a P22 ELISA. Results: The number of SIT test reactors was significantly lower in the group treated with corticosteroids when compared to the pre-sensitised (p < 0.001) and control (p = 0.036) groups. In contrast, pre-sensitisation with bovine and avian PPDs did not cause a significant reduction in the number of SIT and CIT test reactors compared with the control group. In fact, a higher number of reactors was observed after the prior tuberculin injection in the pre-sensitised group (p > 0.05). No significant effect was observed on IGRA and P22 ELISA due to corticosteroids administration. Nevertheless, a previous PPD injection affected the IGRA performance in some groups. Conclusions: The application of topical corticosteroid 24 h before reading the SIT and CIT tests can reduce the increase in skin fold thickness and subsequently significantly decrease the number of positive reactors. Corticosteroids used can be detected in hair samples. A previous pre-sensitisation with bovine and avian PPDs does not lead to a significant reduction in the number of intradermal tests reactors. These results are valuable in order to improve diagnosis of caprine TB and detect fraudulent activities in the context of eradication programs. [ABSTRACT FROM AUTHOR]

A hybrid system of a sequential oxic-anoxic bioreactor and a fluidized immobilized cell carbon oxidation with Kaldnes K1 as supporting material and activated carbon were used to evaluate the removal efficiencies for biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) from domestic wastewater collected at the entrance of the biological reactor from a municipal wastewater treatment plant. The laboratory-scale hybrid biofilm treatment system was fabricated with 5 mm acrylic sheets, the effective volume of the system was 31.6 L. The operation of the treatment system was carried out with an optimal hydraulic retention time of 31.33 h and flow rate of 15 mL/min for 170 d at a mean temperature of 20°C, the pH of the wastewater was between 6.54 and 7.50, and a variable organic loading rate from 0.077 to 1.13 kg BOD5 /(m³d) depending on the daily influent wastewater to the wastewater treatment plant. The means removal efficiencies in the 170 d of operation achieved for BOD5, COD, TN, TP were between 84%–99%, 80%–97%, 24%–97% and 21%–94%, respectively. [ABSTRACT FROM AUTHOR]

The chemical-looping hydrogen generation technology can efficiently produce hydrogen from fossil fuels and separate carbon dioxide. Due to the lack of reactor model suitable for chemical-looping hydrogen generation in commercial process simulation software, which restricts the process simulation and industrial application. A three-fluid bed reactor model for hydrogen generation by chemical-looping process based on axial diffusion equation is established, and the reactor model is embedded in the commercial process simulation software to realize the whole process simulation and optimization. The operation conditions of the three-fluid bed reactor are analyzed. The results show that the steam reactor can produce hydrogen efficiently under the operation temperature of 850 °C and the ratio of steam input flux to natural gas input flux of 2.6, the ratio of hydrogen to methane is 263. 86%. Under the operating temperature of 800 °C and the ratio of Fe2O3 flux to natural gas input flux of 3.82, the CO2 could be separated efficiently and the CO2 capture rate can reach 99.21%. [ABSTRACT FROM AUTHOR]

A novel continuous rapid thermal nucleation method was proposed to prepare hydrolysis seed crystal. The hydrolysis activity, particle size distribution, rutile crystal transformation and pigment properties of the seed were systematically investigated. The results show that the continuous rapid thermal nucleation seed exhibit high hydrolysis activity (reaching 96% with 2% seed addition). The obtained metatitanic acid presents a smaller particle size and more uniform distribution. Moreover, the rutile transformation properties of metatitanic acid from continuous rapid thermal nucleation seed is better without calcined seed. The addition of calcined seed can significantly improve the pigment properties of titanium dioxide product. In order to meet the practical application in the factory, a new shell-tube seed preparation reactor was designed by using Aspen EDR, and the corresponding hydrolysis process was optimized and redesigned. [ABSTRACT FROM AUTHOR]

There are many factors affecting the long-term operation of fixed-bed residue hydrotreating unit, including the rapid rise of pressure drop, hot spot in catalyst bed, scaling of high-pressure heat exchanger, and mismatch between catalyst gradation and operation cycle, etc. In order to extend the running period of the residue hydrotreating unit, refineries can take measures such as strengthening the control of feedstock, using catalysts grading system with high capacity/deprivation ability of metal, using high-performance components, as well as applicating the technology combining rotating upward reactor protection with fixed-bed and the technology combining ebullated bed and fixed-bed to extend the operation cycle of fixed-bed residue hydrogenation unit and improve the economic efficiency of enterprises. [ABSTRACT FROM AUTHOR]

The development of diagnostic methods in medicine as well as the progress in the synthesis of biologically active compounds allows the use of selected radioisotopes for the simultaneous diagnosis and treatment of diseases, especially cancerous ones, in patients. This approach is called theranostic. This review article includes chemical and physical characterization of chosen theranostic radioisotopes and their compounds that are or could be useful in nuclear medicine. [ABSTRACT FROM AUTHOR]

This research utilized a combined hydrodynamic cavitation reactor to produce biodiesel. The reactor worked automatically with the help of a controller designed by LabVIEW. For this purpose, rapeseed oil (0.5 L per experiment) and methanol alcohol with the sodium hydroxide catalyst were used for biodiesel production. The important factors of the study were: 1.pump flow rate (three levels of 1.4, 2 and 2.6 L/min); 2.the molar ratio of methanol to oil (4:1, 6:1 and 8:1); 3.the rotational speed of the reactor (8000, 12000 and 16000 rpm), and 4.circulation time (2, 4 and 6 min). The study analyzed the energy ratio (output energy/input energy) of the produced biodiesel to evaluate the system and modeled the performance of the system to obtain the best-operating conditions of the reactor. In this respect the adaptive neuro-fuzzy inference system (ANFIS), artificial neural network (ANN) and response surface methodology (RSM) methods were employed. The average energy ratio was obtained 1.205, and the R2 of the best ANFIS, ANN and RSM models were 0.989, 0.966, and 0.990, respectively, and MSE was calculated at 0.0005, 0.0015 and 0.00003. The results revealed that the RSM and ANFIS models were preferred to the neural network model in terms of better performance, simplicity, and high processing speed. In general, the RSM model functioned better than the ANFIS model. Accordingly, the best reactor settings to obtain the maximum energy ratio (1.35) and biodiesel yield (91.87 %) was when the circulation time, the rotational speed, the pump flow rate and the molar ratio were set at 2 min, 8000 rpm, 1.4 L/min and 4, respectively.

The relevance the research is caused by the need to ensure uniform heating of the acid solution at the injection rates created by the units onto the thermoacid samples. A solution to this problem will improve the efficiency of acid and thermal acid treatments of highly drained wells with low reservoir pressure. The main aim of the research is to develop and propose a method of acid and thermoacid impulse, a methodology for its application and to create structures for underground and surface equipment of wells for implementation of the developed method. Objects. The volume of the solution poured into the tubing during thermo-acid treatment by the pulsing method depends on their length and inner diameter. Usually it is taken equal to 1,2–2 m3. If the filter or some its part turned out to be blocked with a sand plug in the well, scheduled for thermal acid treatment by the pulsing method, then they were preliminarily cleaned with a thief without opening the sump. A special perforated tip and a special filling head are used as well. Methods. Thermal acid (as well as acidic) treatment of a well by the pulsing method is carried out without the use of a pump unit, which can significantly reduce costs. Accelerating the movement of the acid solution, heating the entire volume to the desired temperature and creating pressure (due to the weight of the solution column) contribute to an increase in the depth of penetration and the effectiveness of the action of the acid on the formation. Results. The most suitable acid solution for thermoacid impulse is 15 % HCl, inhibited by unicol. Good results were obtained by introduction of the acid impulse method, which involves the use of a special tip, in which the nozzle channel is completely closed with a magnesium rod. As a result of the reaction, the magnesium rod dissolves in the acid solution, after which the latter rushes through the vacated choke channel and the perforated pipe into the filter, creating the so-called acid pulse, i. e. increase in the injection rate is achieved under the action of hydrostatic pressure.

The paper presents the results of reactor tests of fuel assemblies with cladding made of zirconium alloy grade СTZ-110 at the material testing reactor of National Research Center (NRC) "Kurchatov Institute" at Novovoronezh and Leningrad NPP under various nuclear fuel burnups. It was shown that after all test cycles, the parts from zirconium in the fuel assemblies were in good condition, which was confirmed by metal research of the samples cut out from the fuel elements. The mechanical properties of the fuel cladding made of СTZ-110 alloy are stable and satisfactory. Maximum burn-outs were achieved in the VVER-1000 mode of 67.4 MW·day/kg of uranium and the RBMK-1000 mode – 76.0 MW·day/kg of uranium.

Lignin depolymerization is a very promising process which can generate value-added products from lignin raw materials. The main objective of lignin depolymerization is to convert the complex molecules of lignin into small molecules. Nevertheless, lignin is natural polymer which the molecules of lignin are extremely complicated due to their natural variability, and it will be a big challenge to depolymerize lignin, particularly high water yield. The various technology and methods are developed to depolymerize lignin into biofuels or bio chemical products including acid/base/metallic catalyzed lignin depolymerization, pyrolysis of lignin, hydroprocessing, and gasification. The distribution and yield of chemical products depend on the reaction operation condition, type of lignin and kind of catalyst. The reactor type, product distributions and specific chemicals (benzene, toluene, xylene, terephthalic acid) production of lignin depolymerization are intensive discussed in this review. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

China is a major agricultural country, and the production of agricultural waste is increasing year by year. However, the utilization rate of resources is still low. Anaerobic dry fermentation technology is mainly used to treat solid organic matter with a total solid content of 20%~40%(wt). It is an effective way to recycle agricultural waste resources, which has the advantages of low water consumption and high volumetric gas production rate. Due to the high solid content, there are still some problems in the anaerobic dry fermentation technology, such as slower reactor start-up, difficulty in mixing materials, and poor heat and mass transfer. Therefore, the innovation of anaerobic dry fermentation equipment and optimization of process parameters will directly affect the further promotion and application of this technology. The research and application status of anaerobic dry fermentation technology at home and abroad in recent years were summarized, the operating characteristics of typical batch and continuous anaerobic dry fermentation reactors were compared, and the effects of main process parameters on anaerobic dry fermentation were analyzed. The shortcomings of the current anaerobic dry fermentation technology were presented, and the future development trend of the technology was prospected in terms of technical equipment and process research, which is to develop design methods for key links in anaerobic dry fermentation equipment, and to carry out in-depth research on mechanisms, such as biogas residue rheological properties and microbial dynamic changes, etc.

Past studies have shown that phosphate recovery in the form of struvite is relatively a simple process, which can be achieved by adding a magnesium source in stored urine. However, struvite recovery process at a decentralised level becomes uneconomical due to high input cost of magnesium salts and operational cost. While use of cheaper alternative magnesium sources such as bittern, low-grade MgO and wood ash could lead to partial cost reduction, it is also important to reduce the overall operational costs to make struvite recovery process economically viable and sustainable. In this study, a continuous flow reactor was developed for low-cost struvite recovery from stored urine at decentralised community scale operations. Our study revealed that over 81.2% of phosphate present in urine can be recovered in the form of struvite. Comparison of results from stirred and unstirred experiments shows that higher recovery efficiency is obtained due to minimal loss of fines. Operation and financial assessment of the process shows that struvite recovery can be profitable due to continuous operation of the reactor requiring minimal process control and manpower requirement.

The depletion of fossil fuels has led to a search for new methods of fuel and chemical production from biomass. One of the methods of converting biomass into valuable products is the process of pyrolysis. This process has been extensively researched in recent years due to the rising prices of energy and chemicals. This work contains basic information on the pyrolysis process concerning the individual components present in the biomass and the types of biomass used in the pyrolysis process. Particular attention was paid to sewage sludge, the management of which is a big challenge. The influence of the most important process parameters (temperature, heating rate, residence time of the solid and vapor, reaction atmosphere) on the pyrolysis products (char, oil, and gas) was presented. The paper presents an overview of the reactors used in the pyrolysis process, from slow to fast pyrolysis, together with their efficiency, advantages, and disadvantages. The analysis of the application of other thermochemical processes for producing the energy used in the process of pyrolysis and in the drying of the biomass was carried out. Two industrial-scale installations for the pyrolysis of sewage sludge were presented.

Stellarator magnetic configurations need to be optimized in order to meet all the required properties of a fusion reactor. In this work, it is shown that a flat-mirror quasi-isodynamic (QI) configuration (i.e. a QI configuration with sufficiently small radial variation of the mirror term) can achieve small radial transport of energy and good confinement of bulk and fast ions even if it is not very close to perfect omnigeneity, and for a wide range of plasma scenarios, including low β and small radial electric field. This opens the door to constructing better stellarator reactors. On the one hand, they would be easier to design, as they would be robust against error fields. On the other hand, they would be easier to operate since, both during startup and steady-state operation, they would require less auxiliary power, and the heat loads on plasma-facing components caused by fast ion losses would be reduced to acceptable levels.

Actually, the quality of water is one of the most important indicators of the human environmental impact, the control of which is crucial to avoiding irreversible damage in the future. Nowadays, in parallel to the growth of the chemical industry, new chemical compounds have been developed, such as dyes and medicines. The increasing use of these products has led to the appearance of recalcitrant pollutants in industrial wastewater, and even in the drinking water circuit of our populations. The current work presents a photoreactor prototype that allows the performance of experiments for the decomposition of coloured pollutants using photocatalysis at the laboratory scale. The design of this device included the study of the photometric technique for light emission and the development of a software that allows monitoring the dye degradation process. Open-source hardware platforms, such as Arduino, were used for the monitoring system, which have the advantages of being low-cost platforms. A software application that manages the communication of the reactor with the computer and graphically displays the data read by the sensor was also developed. The results obtained demonstrated that this device can accelerate the photodegradation reaction in addition to monitoring the changes throughout the process.

During the inactivation of various organic wastes by conventional thermal methods (distillation, desorption), the process temperature is lower than 1300-15000 C. However, this is not sufficient for proper decomposition of waste materials. For the complete decomposition of such materials, the reaction temperature should be raised to 18000 C. This article aims to determine the temperature and velocity profile distributions of the high-temperature gas flow inside the plasma reactor. According to the study, the plasma-chemical method for decomposition of sewage sludge is quite effective. The efficiency of the gas-phase sludge decomposition depends on the plasma flow parameters (temperature, velocity, etc.).

Biofilm reactors, known for utilizing biofilm formation for cell immobilization, offer enhanced biomass concentration and operational stability over traditional planktonic systems. However, the dense nature of biofilms poses challenges for substrate accessibility to cells and the efficient release of products, making mass transfer efficiency a critical issue in these systems. Recent advancements have unveiled the intricate, heterogeneous architecture of biofilms, contradicting the earlier view of them as uniform, porous structures with consistent mass transfer properties. In this review, we explore six biofilm reactor configurations and their potential combinations, emphasizing how the spatial arrangement of biofilms within reactors influences mass transfer efficiency and overall reactor performance. Furthermore, we discuss how to apply artificial intelligence in processing biofilm measurement data and predicting reactor performance. This review highlights the role of biofilm reactors in environmental and energy sectors, paving the way for future innovations in biofilm-based technologies and their broader applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Bacteria in natural ecosystems such as soil, dirt, or debris preferentially reside in the biofilm phenotype. When a traumatic injury, such as an open fracture, occurs, these naturally dwelling biofilms and accompanying foreign material can contaminate the injury site. Given their high tolerance of systemic levels of antibiotics that may be administered prophylactically, biofilms may contribute to difficult-to-treat infections. In most animal models, planktonic bacteria are used as initial inocula to cause infection, and this might not accurately mimic clinically relevant contamination and infection scenarios. Further, few approaches and systems utilize the same biofilm and accompanying substrate throughout the experimental continuum. In this study, we designed a unique reactor to grow bacterial biofilms on up to 50 silica beads that modeled environmental wound contaminants. The data obtained indicated that the reactor system repeatably produced mature Staphylococcus aureus and Pseudomonas aeruginosa biofilms on the silica beads, with an average of 5.53 and 6.21 log 10 colony-forming units per mm 2 , respectively. The bead substrates are easily manipulable for in vitro or in vivo applications, thus improving translatability. Taken together, the bead biofilm reactor presented herein may be a useful system for repeatably growing established biofilms on silica beads that could be used for susceptibility testing and as initial inocula in future animal models of trauma-related injuries.

This study presents an innovative double-walled borosilicate glass reactor system for the efficient treatment of liquid and gaseous wastewater. This reactor system allows precise temperature control, continuous pH monitoring, and controlled dosing of reagents to optimize reaction conditions. Detailed characterization was carried out by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), BET (specific surface area) analysis, point of zero charge (PZC), and scanning electron microscopy (SEM) for the SCR, SCRT, and 5%Fe@SCRT materials. For Malachite Green adsorption, SRCT demonstrated a maximum adsorption capacity of 39.78 ± 0.5 mg/g using the Langmuir isotherm model and followed pseudo-second-order kinetics. Optimum conditions for adsorption were found to be: an initial concentration of 50 ppm, an adsorbent dosage of 1 g/l, a pH of 8.5, and a temperature of 50°C. For the catalytic oxidation of phenol, 5%Fe@SRCT achieved a remarkable removal rate of 99.9 ± 0.1% under optimum conditions (50 ppm phenol, 1 g/l catalyst dosage, pH 3.5, H 2 O 2 concentration 8.7 mM, and temperature 70°C). Intermediates identified during the reaction included hydroquinone, benzoquinone, catechol, and resorcinol, with degradation occurring over a 60-minute reaction period. The 5%Fe@SCRT material showed excellent reusability in the removal of phenol by catalytic oxidation, with no significant loss of efficiency over three cycles, while the SRCT underwent three cycles of regeneration for the adsorption of Malachite Green. Scavenger tests confirmed the involvement of hydroxyl radicals in the catalytic oxidation process. In addition, fish survival tests after catalytic oxidation of phenol by 5%Fe@SRCT showed no impact on fish, underlining the environmental safety of this process. In addition, germination tests after decolorization of MG by SRCT demonstrated a good effect with no negative impact, reinforcing the ecological value of this innovative technology. These results highlight the innovative use of SCRT and 5%Fe@SCRT as versatile materials for environmental remediation, exploiting their effective adsorption capacities and efficient catalytic oxidation performance within the proposed double-walled borosilicate glass reactor system. PRACTITIONER POINTS: The study demonstrates the effectiveness of an innovative reactor system employing SRCT adsorbent and Fe@SRCT catalyst for efficient removal of malachite green and phenol from wastewater. Environmental impact assessment, including seed germination and fish survival evaluation, validates the method's eco-friendly potential. Implementation of this approach could significantly contribute to sustainable water treatment practices., (© 2024 Water Environment Federation.)

Ecosystem destruction is one of today’s significant challenges due to fast industrialisation and an increasing population. It takes several years for solid trash, such as plastic bottles and super-market bags, to decompose in nature. In addition, plastic disposal techniques such as landfilling, reuse, and incineration pose significant threats to human health and the environment. In this paper, we investigated whether the impact of mixing biodiesel with waste oil from recycled plastic on the resulting fuel mixture’s yields better physical and chemical properties. Consequently, pyrolysis is one of the most advantageous and practical waste disposal methods as it is both environmentally benign and efficient. Pyrolysis is the high-temperature thermal breakdown of solid waste to produce pyrolytic oil. The pyrolytic (plastic) oil produced is converted to a hydrocarbon-rich pyrolytic fuel. Similar to diesel and gasoline, pyrolytic fuel has the same calorific value. Internal combustion engines may operate on pyrolytic fuel without suffering a performance reduction. Researchers examined engine performance and exhaust pollutants. The research discovered that the engine could operate on plastic pyrolysis fuel at full load, enhance brake thermal efficiency by 6–8%, and lower UBHC and CO emissions; however, nitrous oxide (NOx) emissions were noticeably higher. The findings demonstrated the possibility of using plastic pyrolysis fuel as a diesel substitute.

This review critically discussed recent developments in hydrothermal carbonization (HTC) of food waste and its valorization to solid fuel. Food waste properties and fundamentals of the HTC reactor were also covered. The review further discussed the effect of temperature, contact time, pressure, water–biomass ratio, and heating rate on the HTC of food waste on the physiochemical properties of hydrochar. Literature review of the properties of the hydrochar produced from food waste in different studies shows that it possesses elemental, proximate, and energy properties that are comparable to sub-bituminous coal and may be used directly as fuel or co-combusted with coal. This work conclusively identified the existing research gaps and provided recommendation for future investigations.