Copper Reactor Research Articles

Enhanced Disinfection Efficiency Using Cu Vortex Diode for Providing Safe Drinking Water: Devising Newer Methodologies

ABSTRACTThe present research aims to refine the hydrodynamic cavitation technique with traditional knowledgebase of Ayurveda for more efficient water disinfection and that has huge potential for implementation in real life, especially for substituting the existing chlorination method for drinking water treatment. The study incorporates use of newer copper reactor configuration, employing vortex flow for generating cavitation for the disinfection of water. Elimination of model contaminant, Escherichia coli, with initial concentration of ∼105 CFU/mL of bacteria was used for the disinfection study. Copper vortex diode with a capacity of 1 m3/h was employed as a cavitating device. The cavitation using copper vortex diode gave significantly higher disinfection, over 30%, compared that with conventional vortex diode, with aluminum as material of construction, under similar conditions. Remarkably, the addition of 0.1% betel leaf oil led to an extraordinary 260‐fold increase in the rate of disinfection, requiring only a single pass to achieve complete bacteria elimination. Furthermore, a notably high synergistic index of 246.96 was achieved for the process intensification approach using the Cu vortex diode. The cost was substantially reduced by approximately three times to 0.011 $/m3 using the Cu vortex diode compared to the conventional vortex diode. The developed strategy offers significantly enhanced performance, as well as a techno‐economical and sustainable solution for drinking water treatment to ensure the provision of safe drinking water. Moreover, the newer methodology can have the advantage of producing no harmful carcinogenic disinfection by‐products compared to chemical disinfection processes apart from sustainable alternative to chlorination.

Numerical simulation of inductively coupled Ar/O<sub>2</sub> plasma

In the inductively coupled plasma (ICP) discharge, surface processes, such as reflection, de-excitation, and recombination, can occur when active species arrive at material surfaces, which accordingly influences the plasma properties. In this work, a fluid model is used to study the Ar/O<sub>2</sub> plasma generated by ICP reactors made of different materials. In simulation, sticking coefficient is employed to estimate the surface reactions on different materials. As the reactor material changes from stainless steel to anodized aluminum to Cu, the sticking coefficient of surface reaction O→1/2O<sub>2</sub> decreases accordingly. It is found that the reactor material has a great effect on species density. In the stainless steel reactor, the density of O atoms at grounded state and excited state are much lower because more O<sub>2</sub> molecules are generated from the surface reaction, yielding a much higher density of <inline-formula><tex-math id="M5">\begin{document}$ {\text{O}}_2^ + $\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M5.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M5.png"/></alternatives></inline-formula> molecular ions which are mainly created from the ionization process of O<sub>2</sub> molecules. Similarly, the high density of O<sub>2</sub> molecules also enhances the production of <inline-formula><tex-math id="M6">\begin{document}${{{\mathrm{O}}} _2}\left( {{{\mathrm{a}}^1}{\Delta _{\mathrm{g}}}} \right)$\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M6.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M6.png"/></alternatives></inline-formula> molecules through the excitation process and O<sup>–</sup> ions through the dissociation attachment reaction. On the contrary, more electrons are consumed via the collisions between electrons and O<sub>2</sub> molecules or <inline-formula><tex-math id="M7">\begin{document}$ {\text{O}}_2^ + $\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M7.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M7.png"/></alternatives></inline-formula> molecular ions. Therefore, the electron density obtained in the Cu reactor is highest. The density of Ar<sup>+</sup> ions and Ar<sub>m</sub> atoms also increase with sticking coefficient decreasing. The density of O<sup>+</sup> ions and <inline-formula><tex-math id="M8">\begin{document}$ {\text{O}}_2^ + $\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M8.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M8.png"/></alternatives></inline-formula> molecular ions peak below the coil in the stainless steel reactor, whereas the radial uniformities are improved in the Cu reactor. In the three reactors, the electrons distribute evenly at the reactor center region. The O density and <inline-formula><tex-math id="M9">\begin{document}${{{\mathrm{O}}} _2}\left( {{{\mathrm{a}}^1}{\Delta _{\mathrm{g}}}} \right)$\end{document}</tex-math><alternatives><graphic specific-use="online" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M9.jpg"/><graphic specific-use="print" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="13-20240436_M9.png"/></alternatives></inline-formula> density significantly peak at the reactor center, while the maximum value of Ar<sup>+</sup> density and Ar<sub>m</sub> density are below the coil. As for O(<sup>1</sup>D), the maximum density below the coil region moves toward the reactor center as the reactor material changes from stainless steel to Cu. Finally, the effect of sticking coefficient of O→1/2O<sub>2</sub> is studied. The results show that the O atom density decreases with the sticking coefficient increasing, but the opposite trend is observed in O<sub>2</sub> molecular density. It is noticed that the sticking coefficient has little effect on species density when it is higher than 0.5.

Effect of the concentration of the starting reagents and the design of the reaction chamber on the morphology and phase composition of the CuxOy@SiO2 nanocomposite synthesized by the pulsed plasma-chemical method

The CuxOy@SiO2 nanocomposite was prepared using a pulsed plasma-chemical method. The regularities of the influence of the concentration of the starting reagents and the design of the reaction chamber on the morphology, phase composition of the CuxOy@SiO2 nanocomposite were revealed. With varying the concentration of the starting reagents, the agglomeration of particles decreased, the particle morphology (particles acquired a spherical shape) and phase composition (the predominant crystalline phases were CuCl2, CuCl, Si, CuO, Cu) changed. Two types of reaction chambers (quartz/copper) were used for the synthesis of the CuxOy@SiO2 nanocomposite. The change in the design of the reaction chamber had an insignificant effect on the phase composition of the CuxOy@SiO2 composites, but had a strong effect on the morphology and average size of the synthesized particles. The morphology of the composite particles prepared in a copper reactor is represented by particles of a fine fraction of an irregular shape.

Design, Construction, and Testing of a Desktop Superconducting Series Reactor Toward the Grid Installation of a Prototype Unit

A desktop superconducting series core reactor (SSR), made from Yttrium barium copper oxide (YBCO) tape, serves as a precursor to a scaled-up, grid-connected prototype unit. The SSR is intended as an alternative to the traditionally employed technologies, including superconducting fault current limiters, when managing fault levels on the electrical power grid. The philosophy of connecting a prototype SSR at a grid-connected research site is first presented before the focus shifts to the desktop SSR. The desktop SSR is a development step before the prototype unit, as it will confirm design construction methodologies and functionality. The desktop SSR is compared to both the fault limiting performance and power consumption of a copper reactor of similar geometry. It was found that the SSR reduced the impact of the applied fault, comparably to the air core reactor (5.9% variance), and was more than four times more energy efficient. Another significant advantage of the SSR would be the significantly reduced footprint required in a typical substation yard.

The novel design of an energy efficient superconductor-based series reactor for installation at a grid connected research site

This paper proposes the development of a superconducting series reactor (SSR) as an alternative to traditionally employed technologies and superconducting fault current limiters when managing fault levels on the electrical power grid. By utilizing superconducting tape, which has negligible resistance, in the construction of a series reactor, it is proposed that fault level mitigation could be achieved in a more energy efficient manner. Once constructed the SSR will be installed and tested at a grid-connected power engineering research site, and the proposed impact of this installation is firstly simulated using Reticmaster® power system simulation software. Design parameters for the prototype SSR are then calculated enabling the total cost of the modifications and prototype SSR to be determined. A desktop SSR was also constructed and tested as a pre-cursor to the prototype construction to confirm functionality and design and was found to be up to four times more energy efficient as the equivalent copper reactor. Finally, the calorimetric method of power loss determination was investigated and experimentally shown to be a viable alternative to the traditional electrical method of power loss determination. In the past, the relatively cheap cost of electricity in South Africa had favoured the installation of poor power efficiency devices that required a lower initial capital investment. With increasing energy costs and a focus on carbon emission reductions, the development of the SSR augurs a new era in power system engineering in which designs are proposed considering both total lifecycle costs and energy efficiency.
 
 Design proposal for the first superconducting power device in Africa
 Alternative to less efficient fault current management technologies currently employed
 Construction and testing of a desktop superconducting series reactor
 Verification of the calorimetric method for power loss determination.

Metallographic Comparison of Copper and Brass Plasma Reactor Electrodes After a Month of Operation

Metallographic Comparison of Copper and Brass Plasma Reactor Electrodes After a Month of Operation

Study of microwave heating of reference liquids in a coaxial waveguide reactor using the experimental, semi-analytical and numerical means

In this work, a new application of coaxial waveguides for microwave heating of individual liquid substances and reaction mixtures is considered. The studied reactor is a small hollow coaxial waveguide in which liquids (methanol or ethanol) are exposed to microwaves generated by a miniature semiconductor source of 2.45-GHz frequency. The temperature of a liquid in the coaxial chamber is measured using an IR temperature sensor, thermocouple and optic fiber probes through non-radiating (in microwave range) openings in the thick copper reactor's wall, with the satisfactory accord between their readings at the medium-level power (10 W). The dynamics of microwave heating is studied using the semi-analytical and numerical simulations, which prove to be in good agreement with the experimental data. Two semi-analytical models of microwave heating in the coaxial waveguide as particular cases of the general electromagnetic-thermal problem are developed. One of them is the lumped system model in which uniformity of the temperature field is assumed. It gives good agreement with the measurements and is physically justified at late heating times. Another one is a simplified non-uniform heating model which is based on consideration of a convective turbulent boundary layer in a short horizontal coaxial waveguide. This model furnishes a quantitative explanation of the measured temperature difference at opposite ends of this waveguide over the entire heating period. The results of this study are interesting for development of miniature reactors for on-demand chemistry and pharmacy.

Experimental and numerical analysis of the biomass innovativ solar pyrolysis process

Paper present the experimental and numerical analysis of biomass photopyrolysis process. The experimental tests is performed on the solar pyrolysis installation, designed in Institute of Thermal Technology, Gliwice. It consist of the copper reactor powered by artificial light simulating sun. The paper shows the result of the solar pyrolysis of wood. The yield of the main fraction as a function of the process temperature is presented. Additionally the gas composition is determined. The numerical model is prepared in the Ansys Fluent 18.2 software, which allow at the same time for capturing geometry of the real system and easy change of input data. The results indicate that both the product yields (liquid, solid and gaseous) and gas components shares are strongly influenced by pyrolysis parameters and feedstock composition.

Continuous Flow Chlorination of Alkenyl Iodides Promoted by Copper Tubing

A simple continuous flow synthesis of alkenyl chlorides from the corresponding readily available alkenyl iodides in copper reactor tubing is described. A variety of alkenyl chlorides were obtained in good to excellent yields with full retention of the double bond geometry. The reaction time was reduced by a factor of 24–48 compared to the batch process.

Design and Analysis of a kA-Class Superconducting Reactor

Abstract —This paper presents the designs of kiloampere-classreactors with high temperature superconducting (HTS) BSCCOtapes. The HTS solenoidal windings of the 100 A-class andkiloampere-class reactors consist of 34 coil layers and 136 coilturns in total. The structural design and performance evaluations,including critical current and ac loss calculations are discussedfor a single-phase grounding fault case and compared with a con-ventional copper reactor. The method to apply the HTS tapes andthe principal features of the HTS reactors have been theoreticallyidentified. Index Terms — AC loss, BSCCO, current limiting reactor, neu-tral grounding reactor, superconducting reactor. I. I NTRODUCTION R EACTORS ARE widely used in modern power systems,which provide functions such as limiting currents, com-pensation of power, and inductive connection to ground. Powerquality and reliability problems are normally caused by theabnormal operations of large-scale equipments and the short-circuit faults caused by the power system itself. High tempera-ture superconductors (HTSs) have been successfully applied inthe advanced reactor developments. As an example, a numberofreactor-basedsuperconductingfaultcurrentlimiters(SFCLs)including the saturated iron-core type [1], [2], transformer type[3], [4] reactor type [5], [6], and non-inductive type [7] aremadeavailabletoreducethefaultcurrentlevelsontransmissionand distribution networks.The power system faults mainly include three-phase shortcircuit, two-phase short circuit, two-phase grounding short cir-cuit and single-phase grounding short circuit. The single-phasegrounding faults, for example, account for about 91.23% of thetotal number of power system faults in the 6434 power trans-mission lines of 220 kV Chinese power grid in 2008. It meansthat single-phase grounding faults need to be solved urgently toimprove the whole power system quality and reliability [8].In the neutral indirectly grounded power systems, the single-phase grounding fault occurs most frequently. The three-phaseline voltages still keep symmetrical states and have negligibleimpact to the local power equipments. Therefore, the powersystem is allowed to continue running up to few hours before

On the Cu precipitation behavior in thermo-mechanically embrittlement processed low copper reactor pressure vessel model steel

Cu precipitation behavior in 30% pre-deformed reactor pressure vessel model steel has been investigated during thermal ageing. In this work, a thermo-mechanical treatment based embrittlement process, including high temperature quenching, pre-deformation and thermal ageing, has been applied to a low-Cu (0.17wt.%) RPV model steel to produce Cu-rich precipitates. Ultrafine Cu-rich precipitates were observed by transmission electron microscope (TEM) and energy dispersive X-ray microanalysis following this embrittlement process. Moreover, differential scanning calorimetry was used to study the structure transformation of Cu precipitates during long-term thermal ageing. It is noted that for dilute Cu containing steel, high temperature quenching and pre-deformation was found to promote the production of high density of vacancies in calculation, which may facilitate the formation of the fine Cu-rich precipitation. As a result, it leads to a significant hardness peak in the initial stage of thermal ageing. The results were discussed to link with the thermo-mechanical embrittlement process, which provides a method for studying the Cu-rich precipitates formation mechanism in steels containing less concentration of impurity Cu.

Verification of a Design Technique of an SFCL System With a Copper Bypass Reactor

This paper presents a study on design technique of superconducting fault current limiters (SFCLs) with a bypass reactor. The SFCL system consists of a non-inductive superconducting coil and a copper coil as a bypass reactor. Since typical resistive SFCL impedance is too high to adopt the existing grid protection scheme, a bypass reactor is required to adjust the impedance. The superconducting coil is a current-driven passive element; hence, connecting a bypass reactor in parallel affects the current sharing between the superconducting coil and the copper reactor. We proposed a design technique to estimate the generated impedance considering the current sharing. The technique is based on a SPICE simulation and thermal finite element analysis (FEA). By comparing to the test result with two kinds of bypass reactors, it is confirmed that the proposed method can simulate all currents and voltages properly. As a result, a case study was conducted on the design of the SFCL system, rated on 13.2 kV/2.5 kA was being considered as a new distribution grid in Korean metropolitan areas.

Ultrasound-assisted click chemistry in continuous flow

We present a study on ultrasound-promoted click chemistry reactions in a meso-flow reactor synthesis system with a copper reactor and a custom sonication piezoelectric transducer. Copper catalyzed Huisgen 1,3-dipolar cycloadditions were studied in flow with this system. Our results demonstrate that 1,4-disubstituted 1,2,3-triazole products can be generated at low temperatures and with short reaction time in good yield, due to the rate enhancement effect of sonication.

Nitrification and potential control mechanisms in simulated premises plumbing

Indigenous drinking water organisms were used to establish nitrification in glass reactors containing copper or polyvinyl chloride (PVC) surfaces. The reactors were fed soil-derived humics as the organic carbon source and ammonium sulfate as the nitrogen source in biologically treated tap water. Water in the reactors was stagnant for 8 h and then flowed for 5 min to simulate conditions in household plumbing. Following the establishment of complete nitrification (conversion of ammonia to nitrate) in both reactor types, various inhibitors of nitrification were tested followed by a period where recovery of nitrification was observed. In one PVC reactor, copper was gradually introduced up to 1.3 ppm. To ensure that most of the copper was in the ionic form, the pH of the influent was then gradually lowered to 6.6. No significant change in nitrification was observed in the presence of copper. Chlorite was introduced into copper and PVC reactors at doses increasing from 0.2 ppm to 20 ppm. There was limited effect on the PVC system and inhibition in the copper reactor only at 20 ppm. Chloramine was tested at chlorine to ammonia ratios ranging from 0.5:1 to 5:1. Nitrification activity was impacted significantly at a 5:1 ratio and ultimately stopped, with the fastest response being in the copper system. Whenever a control mechanism was tested, there was increased release of copper from the reactors with copper coupons. In all cases, nitrification recovered when inhibitors were removed but the rates of recovery differed depending on the treatment method and coupon surface.

Continuous Controlled Radical Polymerization of Methyl Acrylate in a Copper Tubular Reactor

The use of copper tubing as both the reactor and as a catalyst source is demonstrated for continuous controlled radical polymerization of methyl acrylate at ambient temperature and at low solvent content of 30%. The high surface area provided by the copper walls mediates the reaction via the single electron transfer-living radical polymerization (SET-LRP) mechanism. The polymerizations proceeded quickly, reaching 67% conversion at a residence time of 16 min. Ligand concentration could also be reduced without a sharp drop in polymerization rate, demonstrating the potential for decreased raw material and post-process purification costs. Chain extension experiments conducted using synthesized polymer showed high livingness. The combination of living polymer produced at high polymerization rates at ambient temperature and low volatile organic solvent content demonstrate the potential of a copper reactor for scale up of SET-LRP.

Atom Probe Tomography characterization of the microstructural evolution of a low copper reactor pressure vessel steel under neutron irradiation

AbstractA low copper reactor pressure vessel steel was characterised by atom probe tomography after neutron irradiation at different fluences. The specimens were irradiated within the frame of the Surveillance Program of a production reactor. Roughly spherical clusters enriched in nickel, manganese, silicon and, in a lesser extent, phosphorus and copper were observed at all fluences. The chemical composition of these clusters shows no evolution with fluence, as well as their diameter, close to 3 nm. Their number density increases linearly with the neutron fluence. A continuous segregation of the elements found in the clusters is also observed along dislocation lines, with similar enrichments.

Test of Resonance-Type Superconducting Fault Current Limiter

A resonance-type superconducting fault current limiter (FCL) using Bi-2223 superconducting coils was developed and tested in order to demonstrate its actual operation. Over-current tests of the FCL were carried out for 50 Hz steady-state current of up to 120 A with relevant combinations of a superconducting reactor, an arrester, a capacitance and a copper reactor. The test results showed that the currents during faults were controlled within low levels. It was also demonstrated that the FCL could promptly recover to the steady state after the faults were cleared

Preparation and characterization of iron aluminide based intermetallic alloy from titaniferous magnetite ore

Intermetallic alloys such as iron aluminide (Fe 3Al) display an attractive combination of physical and mechanical properties. It is a potential candidate for application demanding high strength, superior oxidation, sulphidation and corrosion resistance. However, the utilization of this alloy is limited owing to problems of its preparation by conventional techniques and poor room temperature ductility. The present paper is, therefore, an attempt to prepare an Fe 3Al-based alloy (iron aluminide alloy) of composition Fe–17.24Al–5.54Cr–1V–0.05C (wt%) by a non-conventional non-furnace process. The process essentially involves the use of cheap, indigenously available titaniferous magnetite ore containing oxides of iron and vanadium and oxide of chromium that are subsequently co-reduced by aluminium in the presence of excess aluminium and a requisite amount of carbon in a specially designed water-cooled copper reactor. The charge composition is judiciously adjusted to attain the alloy composition by utilizing the exothermicity of the overall reactions. The alloy is further characterized with respect to composition, phases and microstructure and properties such as fabricability, hardness, strength and oxidation resistance were studied to indicate its suitability for high temperature applications.

The effect of non-metallic inclusions on the fracture toughness master curve in high copper reactor pressure vessel welds

The fracture toughness of two high copper reactor pressure vessel welds having low upper shelf energy was evaluated in accordance with the master curve method of ASTM E1921. The resultant data were correlated to the metallurgical factors involved in the brittle fracture initiation to provide a metallurgical-based understanding of the master curve. The tests were performed using pre-cracked Charpy V-notched specimens and the master curve was made with an average of T 0 values determined at different temperatures. In all specimens, the cleavage fracture initiated at non-metallic inclusion ranging from 0.7 to 3.5 μm in diameter showing a scatter with the specimens and testing temperatures. Temperature dependency of the triggering particle size was not found. The fracture toughness ( K J C ) was inversely proportional to the square root of the triggering inclusion diameter ( d i ) at respective temperatures. From this relationship, we determined median K J C values which correspond to the average value of triggering inclusion diameter of all tested specimens and defined them as a modified median K J C ( K ′ J C(med) ). The obtained K ′ J C(med) values showed quite smaller deviation from the master curve at different temperatures than the experimental median K J C values. This suggests that the master curve is on the premise of a constant dimension of key microstructural factor in a material regardless of the testing temperature. But the inclusion size at trigger point played an important role in the absolute position of the master curve with temperature and the consequent T 0 value.

Studies on preparation, characterisation and evaluation of properties of Fe 3Al-based intermetallic alloy of composition Fe–16Al–5.44Cr–1Nb–0.5C

Efforts on preparation of iron aluminide-based (Fe 3Al) alloys by various techniques are being explored worldwide in view of their excellent combination of metallurgical properties suitable for high temperature applications. So far no process has yet emerged suitable for its commercial exploitation. In the present investigation, an attempt has been made to prepare Fe 3Al-based alloy (iron aluminide alloy) of composition Fe–16Al–5.44Cr–1Nb–0.5C (wt.%) by non-conventional non-furnace process. The process essentially involves the use of cheap, indigenously available oxides of iron, chromium and niobium for their co-reduction with large excess of aluminium, in presence of carbon under flowing argon atmosphere in a specially designed water cooled copper reactor. The charge composition is judiciously adjusted to fulfil two functions simultaneously. Firstly, to attain the alloy composition and secondly, to utilise exothermicity of the overall reactions for their successful completion. A typical charge constituting Al 10 wt.% over stoichiometric amount, Cr 2O 3 stoichiometric amount, Nb 2O 5 and C, double the requisite theoretical amount and lime (CaO) 10 wt.% of total charge (specific heat, 2930 kJ kg −1) resulted in an alloy of nearly targeted composition with about 98 wt.% yield. The alloy formation by the above technique is substantiated by studies on alloy characterisation with respect to composition, phases and microstructure and property evaluation by strength, hardness, rolling and oxidation resistance to indicate its suitability for high temperature applications.