Journal articles: 'Materials processing reactors'

1

Nozaki, Tomohiro, and Ken Okazaki. "Materials processing at atmospheric pressure: Nonequilibrium effects on nanotechnology and mega-industries." Pure and Applied Chemistry 78, no. 6 (January 1, 2006): 1157–72. http://dx.doi.org/10.1351/pac200678061157.

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Applications of atmospheric pressure nonequilibrium plasmas, because of their special advantages of forming reactive plasmas in a simple reactor, are spreading into various engineering fields, not only of materials processing, but also into energy and environment areas. Our group has explored new applications of both filamentary and diffuse barrier discharges, including the establishment of appropriate modeling, which enables better optimization of given plasma processes. More recently, microplasmas produced in submillimeter to micrometer reactors are also highlighted in association with atmospheric pressure nonequilibrium plasma because such small-scale plasmas frequently require high-density media to produce. This paper overviews our recent projects: (1) steam reforming of methane using filamentary barrier discharge; (2) deposition of carbon nanotubes in atmospheric pressure radio frequency discharge (APRFD); and (3) synthesis of silicon nanoparticles using microplasma.

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Yang, Guixiang, Zhongming Wang, Pratim Biswas, Wayne Bresser, and Punit Boolchand. "Processing titania based materials in flame reactors: from dopants to nano-composites." Journal of Aerosol Science 29 (September 1998): S129—S130. http://dx.doi.org/10.1016/s0021-8502(98)00189-x.

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Lin, Roger, Jiaxun Guo, Xiaojia Li, Poojan Patel, and Ali Seifitokaldani. "Electrochemical Reactors for CO2 Conversion." Catalysts 10, no. 5 (April 26, 2020): 473. http://dx.doi.org/10.3390/catal10050473.

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Increasing risks from global warming impose an urgent need to develop technologically and economically feasible means to reduce CO2 content in the atmosphere. Carbon capture and utilization technologies and carbon markets have been established for this purpose. Electrocatalytic CO2 reduction reaction (CO2RR) presents a promising solution, fulfilling carbon-neutral goals and sustainable materials production. This review aims to elaborate on various components in CO2RR reactors and relevant industrial processing. First, major performance metrics are discussed, with requirements obtained from a techno-economic analysis. Detailed discussions then emphasize on (i) technical benefits and challenges regarding different reactor types, (ii) critical features in flow cell systems that enhance CO2 diffusion compared to conventional H-cells, (iii) electrolyte and its effect on liquid phase electrolyzers, (iv) catalysts for feasible products (carbon monoxide, formic acid and multi-carbons) and (v) strategies on flow channel and anode design as next steps. Finally, specific perspectives on CO2 feeds for the reactor and downstream purification techniques are annotated as part of the CO2RR industrial processing. Overall, we focus on the component and system aspects for the design of a CO2RR reactor, while pointing out challenges and opportunities to realize the ultimate goal of viable carbon capture and utilization technology.

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Bose, Deepak, David Hash, T. R. Govindan, and M. Meyyappan. "Modelling of inductively coupled plasma processing reactors." Journal of Physics D: Applied Physics 34, no. 18 (September 5, 2001): 2742–47. http://dx.doi.org/10.1088/0022-3727/34/18/305.

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Vasiliev, Michael, Tatiana Vasilieva, and Aung Miat Hein. "Hybrid plasma chemical reactors for bio-polymers processing." Journal of Physics D: Applied Physics 52, no. 33 (June 18, 2019): 335202. http://dx.doi.org/10.1088/1361-6463/ab222a.

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Uhland, Eberhard, and Werner Wiedmann. "Perspectives in application of screw reactors in plastics processing." Macromolecular Symposia 83, no. 1 (May 1994): 59–75. http://dx.doi.org/10.1002/masy.19940830108.

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Semenina, A. V., Yu Yu Baklanova, and A. D. Vurim. "STRUCTURING EXPERIMENTAL DATA ON HIGH-TEMPERATURE INTERACTION BETWEEN CORIUM AND STRUCTURAL MATERIALS OF POWER REACTOR AS INFORMATION-ANALYTICAL SYSTEM." NNC RK Bulletin, no. 1 (May 1, 2021): 54–60. http://dx.doi.org/10.52676/1729-7885-2021-1-54-60.

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The RSE NNC RK branch “Institute of Atomic Energy” has been conducted investigations in the field of nuclear power safety since the late 1982. These investigations have recently resulted in accumulation of a vast amount of experimental data widely applied in creation, verification and validation of calculation codes intended to analyze behavior of nuclear reactors under transient and emergency modes including analysis of reactor conditions in the course of propagation of severe accident with fuel melting. However, a positive effect of application these data has drastically dropped because there is no systematic approach for solution such problems like collection, processing and storing of experimental results along with planning and conducting of the experiments to receive the data that are missed but required for complete understanding of severe accident propagation. In this connection it is obviously that data integration as information-analytical system (IAS) will make it possible to create multifunctional tool for data storing, processing and analysis as well as to get the data much more applicable useful.

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Gottscho, Richard A., Toshiki Nakano, Nader Sadeghi, Dennis J. Trevor, and T. C. Lee. "Diagnostics of high density plasma reactors used in the processing of electronic and photonic materials (invited) (abstract)." Review of Scientific Instruments 63, no. 10 (October 1992): 4920. http://dx.doi.org/10.1063/1.1143548.

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Ozhmegov, Kirill, Anna Kawalek, Dariusz Garbiec, Henryk Dyja, and Alexandr Arbuz. "Development of Alternative Method for Manufacturing Structural Zirconium Elements for Nuclear Engineering." Materials 14, no. 17 (September 2, 2021): 5006. http://dx.doi.org/10.3390/ma14175006.

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Zirconium is used as a structural material for use in aggressive environments, including the core of nuclear reactors. The traditional technology of manufacturing the structural elements of zirconium nuclear reactors is characterized by a long technological process and a significant amount of waste in the form of metal shavings. The paper presents the results of an alternative technology, spark plasma sintering, for manufacturing zirconium products. A complex of microstructural and mechanical studies of the obtained samples was carried out according to the ASTMB-351 standard. The sintering of zirconium powder and options for subsequent processing by various methods, including non-standard ones such as radial shear rolling, are justified.

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10

Rosa. "Solar Heat for Materials Processing: A Review on Recent Achievements and a Prospect on Future Trends." ChemEngineering 3, no. 4 (October 8, 2019): 83. http://dx.doi.org/10.3390/chemengineering3040083.

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Considering works published in the literature for more than a decade (period from January 2008 till June 2019), this paper provides an overview of recent applications of the so-called “solar furnaces”, their reactors, process chambers and related devices, aiming specifically at the processing of (solid) materials. Based on the author’s own experience, some prospects on future trends are also presented. The aim of this work is to demonstrate the tremendous potentialities of the usage of solar heat for materials processing, but also to reveal the necessity of further developing solar-driven high-temperature technologies (which are required to displace the use of electricity or natural gas). In particular, it is essential to improve the temperature homogeneity conditions inside reaction chambers for materials processing using solar heat. Moreover, new innovative modular systems, practical and flexible, for capture, concentration, control and conduction of concentrated solar radiation are suggested. Solar thermal technologies for the production of electricity, as well as solar thermochemical processes for production of gases or liquids, are outside the scope of this review.

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Ahn, Jung Ho, Sang Hyun Lee, and Jin Sung Jang. "Mechanical Alloying and Properties of ODS Ferritic Steels." Advanced Materials Research 15-17 (February 2006): 696–701. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.696.

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Oxide-dispersion strengthened (ODS) ferritic stainless steels have been considered as promising high-temperature materials such as interconnects for oxide-fuel cells and nuclear materials for Liquid Metal Fast Reactors or Super-Critical-Water-Cooled Reactors. In the present work, we have prepared Fe-14Cr-2Al-1Si-0.3Ta-1Y2O3 ferritic stainless steels which were dispersion-strengthened by nano-sized Y2O3 via mechanical alloying of elemental powder mixtures and subsequent hot consolidation. A comparison was made with MA 957 and DY-01 alloys. The mechanically alloying behaviour and consolidated mechanical properties of the Fe-14Cr-2Al-1Si- 0.3Ta-1Y2O3 ferritic steels were strongly influenced by processing parameters, especially milling atmosphere. The stability of yttrium oxides and oxidation resistance at high temperatures were examined. The preliminary result shows that the mechanically alloyed Fe-14Cr-2Al-1Si-0.3Ta- 1Y2O3 ferritic stainless steel exhibits interesting properties to be exploited as high temperature materials.

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Saito, N., Y. Tsuchiya, Y. Akai, H. Omura, T. Takada, and N. Hara. "Corrosion Performance of Metals for Supercritical Water, Oxidation-Utilized Organic Waste-Processing Reactors." CORROSION 62, no. 5 (May 2006): 383–94. http://dx.doi.org/10.5006/1.3278276.

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Veleva, Lyubomira, Robin Schäublin, Tomasz Plocinski, Mario Walter, and Nadine Baluc. "Processing and characterization of a W–2Y material for fusion power reactors." Fusion Engineering and Design 86, no. 9-11 (October 2011): 2450–53. http://dx.doi.org/10.1016/j.fusengdes.2011.02.011.

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Mansurov, Z. A. "Environmentally Friendly Technologies Based on Combustion Processes." Eurasian Chemico-Technological Journal 3, no. 4 (July 10, 2017): 291. http://dx.doi.org/10.18321/ectj579.

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The paper reviews some technologies basing on Combustion chemistry processes being developed in the Combustion Problems Institute (ICP), there are: • Obtaining of target products in cool flame hydrocarbon oxidation; • Catalytic methane combustion; • Sooting flames as chemical reactors; • Oil wastes processing into road-building materials; • Solid phase combustion of oxide systems.

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15

Ewing, R. C., and W. Lutze. "Materials Science of Radioactive Waste Forms." MRS Bulletin 19, no. 12 (December 1994): 16–19. http://dx.doi.org/10.1557/s0883769400048636.

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The materials science of radioactive waste forms and containment materials has long been a subject of interest to the Materials Research Society. One of the earliest (and continuing) MRS symposia, the Scientific Basis for Nuclear Waste Management, has been held 18 times since 1978. This symposium rotates abroad every third year: Berlin in 1982, Stockholm in 1985, Berlin in 1988, Strasbourg in 1991, and Kyoto this past October. Nearly 170 papers were presented at the Kyoto meeting.Materials science issues for nuclear waste disposal are unique in their scale and consequences. The wastes include an extremely wide variety of materials: spent nuclear fuel from commercial and research reactors; high-level liquid waste produced at West Valley, New York, during the reprocessing of commercial spent nuclear fuel; high-level waste (HLW) generated by the nuclear weapons program; nearly pure plutonium from the dismantling of nuclear weapons; highly enriched uranium from weapons; low-level, medium-level, and mixed waste from laboratories and medical facilities; and, finally, mill tailings from uranium mines and the residues from chemical processing, such as the radium-bearing filtrate presently in storage at Fernald, Ohio, and Niagara Falls, New York. Some material can be simply stabilized and monitored in situ, as is done for most uranium mill tailings and residues, but other materials require retrieval, processing, immobilization, and permanent disposal. The volumes of material that will require handling, immobilization, and disposal are enormous. In the United States, much of the weapons program waste is stored in tanks at Hanford, Washington and Savannah River, South Carolina.

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Khiari, Besma, Marwa Moussaoui, and Mejdi Jeguirim. "Tomato-Processing By-Product Combustion: Thermal and Kinetic Analyses." Materials 12, no. 4 (February 13, 2019): 553. http://dx.doi.org/10.3390/ma12040553.

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This paper is part of a sustainable development approach, the aim being to develop a thermochemical energy recovery path while reducing the amount of tomato waste issued from agro-industrial units. The thermal process may contribute to an environmentally friendly management and help tomato processing industries creating new economic profitable circuits in an increasingly competitive context. The adopted approach was to follow the operating conditions needed for a complete thermal degradation through a thermal and kinetic analyses. The results of the tomato waste characterization confirmed their suitability to a thermochemical processing with high volatiles and fixed carbon and interesting high heating values comparable to sawdust biomass. We were able to isolate of the decomposition domains and extract kinetic parameters. Three kinetic models were applied; Flynn–Wall–Ozawa (FWO) simulated the best the combustion process. Calculated curves were validated by the first order (n = 1) model except for the slow heating rate of 5 °C/min which was fitted by the contracted cylinder model. The conclusions of this paper could help in optimizing the combustion process in order to achieve high energy recovery from tomato residues. Obtained kinetic data would help in the design of combustion reactors.

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Akhmedov, Mansur, Abdulla Dadakhodzhaev, and Vitaliy Guro. "ANTI-ICE REAGENT ON THE BASIS OF DOLOMITE, NITROGEN ACID AND CARBAMIDE." International Journal of Engineering Technologies and Management Research 5, no. 10 (March 23, 2020): 45–52. http://dx.doi.org/10.29121/ijetmr.v5.i10.2018.301.

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For the safe operation of pavements in the cold season, especially in mountainous areas, antiicing means are required. The task was to develop the technology of their production from local raw materials. A domestic anti-icing reagent, from unbaked dolomite from Dekhkanabad deposit of Uzbekistan was offered, consisting of calcium, magnesium nitrates and carbamide. Standard chemical-analytical methods for investigating raw materials, laboratory technological methods, enlarged pilot-industrial approaches to the methods of its processing, followed by the development of technology for obtaining the required dolomite’s derivatives, as well as its implementation at JSC "Maxam-Chirchik" were used. Sulfur-hydrochloric acid’s processing of dolomite provided bischofite’s obtaining in industrial reactors. As the result, optimal conditions for obtaining anti-ice reagent were selected for its industrial production.

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Bianchini, Leonardo, Paolo Costa, Pier Paolo Dell’Omo, Andrea Colantoni, Massimo Cecchini, and Danilo Monarca. "An Industrial Scale, Mechanical Process for Improving Pellet Quality and Biogas Production from Hazelnut and Olive Pruning." Energies 14, no. 6 (March 13, 2021): 1600. http://dx.doi.org/10.3390/en14061600.

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The effects of a mechanical process on the solid fuel quality and anaerobic biodegradability of hazelnut and olive pruning were determined. The feedstock was treated using a two-stage dry milling process, followed by fractionation into four different products. The coarser products from the processing of both the raw materials, named C and M, were notable for the high reduction in both the ash and nitrogen content. Therefore, for hazelnut, they met the requirement of the EN ISO 17225-2 standard for both the industrial and residential pellets, whereas C and M from olive processing met the requirements only for the industrial pellet. The raw materials and the finest products from processing, named F1 and F2, were anaerobically digested in batch reactors under mesophilic conditions. The F2 product from hazelnut processing reached a methane yield of 118.1 Nm3 tVS−1, corresponding to a +70.1% gain over the untreated substrate, whereas F2 from olive pruning processing reached 176.5 Nm3 tVS−1, corresponding to a methane yield gain of about +93.5% over the untreated raw material. These results suggest that the investigated process could be successfully used to improve the quality of pruning and establish new markets for them.

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Valtseva, A. I., P. S. Pershin, A. V. Suzdaltsev, and Yu P. Zaikov. "Research of oxygen-conducting ceramic materials for lithium chloride melt in reactors for pyrochemical processing of spent nuclear fuel." Journal of Physics: Conference Series 1683 (December 2020): 032029. http://dx.doi.org/10.1088/1742-6596/1683/3/032029.

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Tuncev, Denis, Vitaliy Har'kov, and Maksim Kuznecov. "PROCESSING SUNFLOWER HUSK INTO HIGH STRENGTH COAL BRIQUETTES." Vestnik of Kazan State Agrarian University 14, no. 4 (April 12, 2020): 86–90. http://dx.doi.org/10.12737/2073-0462-2020-86-90.

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An urgent problem of the modern agro-industrial complex is the low efficiency of the use of secondary raw materials. On the basis of Rosstat data, in 2018 almost 13 million tons of sunflower seeds were collected in the country, which led to the accumulation of up to 1.8-3.2 million tons of husk, which is the ballast component of the technology for producing sunflower oil. Oil refineries continuously bear the costs of storage, safety, and the removal and disposal of such waste in landfills. Sunflower husk has a high calorific value, so thermochemical processing methods allow for the integrated processing of unclaimed raw materials of plant origin with moderate capital costs in energy and various chemical products. An experimental laboratory setup for conductive pyrolysis of plant materials has been developed to produce high-strength coal briquettes. The advantages of conductive heat feed pyrolysis reactors are simplicity of design and ease of maintenance. The results of a pilot study of the conductive pyrolysis process of sunflower husk showed that the obtained coal briquettes have a low ash content (6.2%), their maximum yield (29%) was achieved at a pressing pressure of 25 kg/cm2, and the maximum density of the samples was 1139 kg/cm3 (pressing pressure 153 kg/cm2). It was found that an increase in pressing pressure from 20 to 150 kg/cm2leads to an increase in the density of coal briquettes by 16%, and the maximum value of compression pressure is 566 kg/cm2. Also, at a compaction pressure of more than 50 kg/cm2, the impact resistance index during discharge reaches 100%. The developed technology provides a large mass yield of coal briquettes with high quality characteristics, which indicates the promise of utilizing sunflower husk by conductive pyrolysis in the fuel feed for the metallurgical industry.

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Isayev, A. I., J. Chen, and A. Tukachinsky. "Novel Ultrasonic Technology for Devulcanization of Waste Rubbers." Rubber Chemistry and Technology 68, no. 2 (May 1, 1995): 267–80. http://dx.doi.org/10.5254/1.3538741.

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Abstract A novel patented process and several reactors have been developed for devulcanization of waste rubbers. The technology is based on the use of the high power ultrasonics. The ultrasonic waves of certain levels in the presence of pressure and heat rapidly break up the three-dimensional network in crosslinked rubbers. The devulcanized rubber can be reprocessed, shaped and revulcanized in much the same way as a virgin rubber. The first laboratory reactor has been scaled up to pilot-plant level by the National Feedscrew and Machining, Inc. Various devulcanization experiments were carried out with model styrene-butadiene rubber (SBR) and with ground rubber tire (GRT). Curing behavior, Theological properties, and structural characteristics of rubbers devulcanized at various processing conditions were studied, as well as mechanical properties of revulcanized rubber samples. A possible mechanism of the devulcanization is discussed. The performed measurements indicate that the rubbers are partially devulcanized, and the devulcanization process is accompanied by certain degradation of the macromolecular chains. In spite of these observations, the processing conditions are identified at which the retention of the mechanical properties is found to be good. A further work is in progress to find the optimal conditions of devulcanization and to improve the selectivity of the process towards breaking up the chemical network only.

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Fia, Fátima R. L., Antonio T. Matos, Alisson C. Borges, Ronaldo Fia, and Paulo R. Cecon. "Treatment of wastewater from coffee bean processing in anaerobic fixed bed reactors with different support materials: performance and kinetic modeling." Journal of Environmental Management 108 (October 2012): 14–21. http://dx.doi.org/10.1016/j.jenvman.2012.04.033.

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Robinson, Sharon M., Dennis E. Benker, Emory D. Collins, Julie G. Ezold, Jon R. Garrison, and Susan L. Hogle. "Production of Cf-252 and other transplutonium isotopes at Oak Ridge National Laboratory." Radiochimica Acta 108, no. 9 (September 25, 2020): 737–46. http://dx.doi.org/10.1515/ract-2020-0008.

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AbstractIn 1957 Glenn T. Seaborg conceived and advocated for the construction of the High Flux Isotope Reactor (HFIR) and the Transuranium Processing Plant (since then renamed the Radiochemical Engineering Development Center, or REDC) at Oak Ridge National Laboratory. Heavily shielded hot cells, glove boxes, and laboratories allow recovery of transuranium elements produced in substantial quantities. Seaborg’s vision of HFIR and REDC producing milligram quantities of berkelium, californium, and einsteinium has been fulfilled beginning in 1966 through May 2019 with 78 production campaigns yielding a cumulative totals of 1.2 g of 249Bk, 10.2 g of 252Cf, 39 mg of 253Es, and 15 pg of 257Fm. Notably, 252Cf is a neutron source used in many industrial applications including oil exploration; process control systems for the cement industry, coal analysis, and power production; sources to start nuclear reactors and perform nondestructive materials analyses; homeland security and national defense detection devices; and medical research. Isotopes made available through transplutonium production at HFIR/REDC have enabled scientists to study the nuclear properties and reactions, chemical properties, optical properties, and solid-state properties of transplutonium elements. Long-lived isotopes have served as targets in heavy ion accelerators to produce heavier elements leading to the discovery of 104Rf, 105Db, 106Sg, 113Nh, 114Fl, 115Mc, 116Lv, 117Ts, and 118Og. This paper reviews the evolution of the processing flowsheets to produce, separate, and purify transplutonium isotopes, which have evolved over 50 years of operation at HFIR and REDC, and summarizes directions of future work to improve the efficiency of the production operations.

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Phiwluang, Worapong, and Mudjalin Poonprasit. "Potential of Using Natural Materials as Support Media in Anaerobic Filter for Tapioca Wastewater Treatment." Advanced Materials Research 931-932 (May 2014): 687–92. http://dx.doi.org/10.4028/www.scientific.net/amr.931-932.687.

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Tapioca starch manufacturing generated a large amount of wastewater containing high organic matter contents. Wastewater from tapioca starch manufacturing thus had a high potential for biogas recovery. In Thailand, biogas recovery from tapioca wastewater has been performed via a UASB system for large-scale manufacturers and a cover lagoon system for small-to medium-scale manufacturers. Settling the UASB system on a tapioca starch processing site required high investment and operation cost, whilst settling the cover lagoon system required a land area. There were a number of studies identifying that the anaerobic filter system, using natural materials as support media, had a high efficiency for treatment and biogas recovery of agro-industrial wastewater containing high organic contents. This research was begun with the idea to seek for a proper technique for treatment and biogas recovery, with high effectiveness and low cost, of wastewater from small-to medium-scale tapioca production plants. The studied materials, used as support media, were two natural materials (burnt corn cobs and charcoal) and synthesis material (plastic balls). The research experiment has been undertaken, using three laboratory-scale anaerobic filter reactors. The initial findings have showed that wastewater treatment efficiencies, as well as biogas production capacities, of the two reactors containing selected natural support media types and the one containing synthesis media type were in the same range. The COD removal efficiencies were 95.42% to 97.90%. The SS removal efficiencies were 78.12% to 85.32%. The methane contents of biogas produced were 73.45% to 75.06%.

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Dąbrowska, Sylwia, Tadeusz Chudoba, Jacek Wojnarowicz, and Witold Łojkowski. "Current Trends in the Development of Microwave Reactors for the Synthesis of Nanomaterials in Laboratories and Industries: A Review." Crystals 8, no. 10 (September 27, 2018): 379. http://dx.doi.org/10.3390/cryst8100379.

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Microwave energy has been in use for many applications for more than 50 years, from communication, food processing, and wood drying to chemical reactions and medical therapy. The areas, where microwave technology is applied, include drying, calcination, decomposition, powder synthesis, sintering, and chemical process control. Before the year 2000, microwaves were used to produce ceramics, semiconductors, polymers, and inorganic materials; in next years, some new attempts were made as well. Nowadays, it has been found that microwave sintering can also be applied to sintered powder and ceramics and is more effective than conventional sintering. Particularly interesting is its use for the synthesis of nanomaterials. This review identifies the main sources of microwave generation, the delivery mechanisms of microwave energy, and the typical designs and configurations of microwave devices, as well as the measurement and construction material problems related to microwave technology. We focus our attention on the configurations, materials, optimized geometries, and solvents used for microwave devices, providing examples of products, especially nanoparticles and other nanomaterials. The identified microwave devices are divided into four groups, depending on the scale, the maximum pressure developed, the highest temperature for sintering, or other special multi-functions. The challenges of using microwave energy for the synthesis of nanopowders have been identified as well. The desirable characteristics of microwave reactors in the synthesis of nanostructures, as well as their superiority over conventional synthetic methods, have been presented. We have also provided a review of the commercial and self-designed microwave reactors, digestors, and sintering furnaces for technology for synthesis of nanomaterials and other industries.

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Liu, H.-C., H. Tsuru, A. G. Cooper, and F. B. Prinz. "Rapid prototyping methods of silicon carbide micro heat exchangers." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 219, no. 7 (July 1, 2005): 525–38. http://dx.doi.org/10.1243/095440505x32463.

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Conventional heat exchangers are mainly constructed of metal alloys. The manufacturing process of metal alloys usually requires assembling and joining techniques such as welding and diffusion bonding. In addition, the structures are limited to simple shapes due to the restrictions of the fabrication methods. This research focused on the manufacturing of compact heat exchangers made of high thermal-conductivity ceramic material, rather than on the performance of the devices. To achieve a high surface-volume ratio in heat exchangers, a strategy was adopted that fabricates miniaturized devices with a high shape complexity. This paper discusses an approach that uses a combination of mould shape deposition manufacturing (Mould SDM) and the gelcasting process to fabricate monolithic ceramic heat exchangers. This approach not only makes one-piece heat exchangers possible but introduces materials with superior thermal properties to the heat management applications. Silicon carbide is chosen for such applications because of its high thermal conductivity, thermal resistance, and corrosion resistance. The high chemical resistance of ceramic materials also extends the use of heat exchangers to chemical processing devices such as chemical reactors. The initial investigation of the process for micro reactors is also discussed.

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González Niño, Carlos, Nikil Kapur, Marco-Felipe King, Gregory de Boer, A. John Blacker, Richard Bourne, and Harvey Thompson. "Computational fluid dynamic enabled design optimisation of miniaturised continuous oscillatory baffled reactors in chemical processing." International Journal of Computational Fluid Dynamics 33, no. 6-7 (August 9, 2019): 317–31. http://dx.doi.org/10.1080/10618562.2019.1683169.

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Lin, Guo Qing. "Characterization of Hot Deformation Behavior of Zr-4 Alloy in Material Application Area." Advanced Materials Research 578 (October 2012): 202–5. http://dx.doi.org/10.4028/www.scientific.net/amr.578.202.

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The hot deformation behavior of Zr-4 alloy was studied in the temperature range 650-900°C and strain rate range 0.005-50s-1 using processing maps. The processing maps revealed three domains: the first occurs in the temperature range 780-820°C and strain rate range 0.005-0.05s-1, and has a peak efficiency of 45% at 790°C and 0.005s-1; the mechanism is the dynamic recrystallization. The second occurs in the temperature range greater than 900°C and strain rate range 0.05-0.8s-1, and has a peak efficiency of 40% at 900°C and 0.5s-1, which are the domains of dynamic recovery. In addition, the instability zones of flow behavior can also be recognized by the maps in the temperature range 650-780°C and strain rate range 0.01-0.1s-1, which should be strictly avoided in the processing of the material. Zr-4 alloy is the material for pressure tube applications in nuclear reactors and has better strength and a lower rate of hydrogen uptake compared to other materials under similar service conditions.

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Żak, Sławomir, Teresa Rauckyte-Żak, Alfredas Laurinavičius, and Paweł Siudziński. "Research on physico-chemical pretreatment of wastewater from the production of wood coating materials." Ecological Chemistry and Engineering S 21, no. 1 (March 1, 2014): 101–12. http://dx.doi.org/10.2478/eces-2014-0009.

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Abstract This paper presents the results of the research conducted on the installation designed for physico-chemical pretreatment of technological wastewater in the volume of up to 5.0 m3/day discharged from the production of protective and decorative coating materials used for wooden surfaces. The subject-matter installation constructed on a mobile pallet, consisted of a storage-averaging tank where concentrations were equalised with the use of circulation aeration and mixing. A variant, preliminary pre-oxidation with the use of hydrogen peroxide was conducted in this tank. A substantial installation set for the wastewater treatment plant consisted of two preliminary tube reactors, one cylindrical-conical processing reactor, stations for preparing and dispensing reagents and the sediment dewatering station. Considerable reductions in main chemical indicators of water pollution were obtained in the installation: both total suspended solids (TSS) and ether extract (EE) - more than 98%, chemical oxygen demand (COD) - 46-54%, biochemical oxygen demand (BOD5) - 39-46%, and free formaldehyde (HCHO) - 14-27% due to the use of pre-oxidation and the acid - alkaine double coagulation by applying the ALCAT 105 - SAX 25 system. The use of pre-oxidation with hydrogen peroxide in doses 250.0-450.0 mg/l and then two-stage coagulation resulted in an increase in the reduction of: COD and BOD5 by ca 10-15%, and HCHO by ca 58-66% with reference to the water pretreatment without pre-oxidation. The assessment of sediments formed during the process of pretreatment was made determining the leachable forms of metals (Cu, Ni and Ti) according to methodology of TCLP in compliance with the US EPA Method 1311.

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Tosti, Silvano, and Alfonso Pozio. "Membrane Processes for the Nuclear Fusion Fuel Cycle." Membranes 8, no. 4 (October 12, 2018): 96. http://dx.doi.org/10.3390/membranes8040096.

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This paper reviews the membrane processes for the nuclear fusion fuel cycle—namely, the treatment of the plasma exhaust gases and the extraction of tritium from the breeding blankets. With respect to the traditional processes, the application of membrane reactors to the fusion fuel cycle reduces the tritium inventory and processing time, thus increasing the safety and availability of the system. As an example, self-supported Pd-alloy membrane tubes have been studied for the separation of hydrogen and its isotopes from both gas- and liquid-tritiated streams through water-gas shift and isotopic swamping reactions. Furthermore, this paper describes an innovative membrane system (Membrane Gas–Liquid Contactor) for the extraction of hydrogen isotopes from liquid LiPb blankets. Porous membranes are exposed to the liquid metal that penetrates the pores without passing through them, then realizing a gas–liquid interface through which the mass transfer of hydrogen isotopes takes place. Compared to the conventional hydrogen isotope extraction processes from LiPb that use the “permeator against vacuum” concept, the proposed process significantly reduces mass-transfer resistance by improving the efficiency of the tritium recovery system.

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Slobodyan, Mikhail. "High-energy surface processing of zirconium alloys for fuel claddings of water-cooled nuclear reactors." Nuclear Engineering and Design 382 (October 2021): 111364. http://dx.doi.org/10.1016/j.nucengdes.2021.111364.

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Pachaiyappan, R., R. Gopinath, and S. Gopalakannan. "Processing Techniques of a Silicon Carbide Heat Exchanger and its Capable Properties – A Review." Applied Mechanics and Materials 787 (August 2015): 513–17. http://dx.doi.org/10.4028/www.scientific.net/amm.787.513.

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Silicon carbides is a composite ceramic material produced from inorganic non-metallic substances, formed from the molten mass which solidifies on cooling and simultaneously matured by the action of heat. It is used in various applications such as grinding wheels, filtration of gases and water, absorption, catalyst supports, concentrated solar powers, thermoelectric conversion etc. The modern usage of silicon carbide is fabricated as a heat exchanger for high temperature applications. Leaving behind steel and aluminium, silicon carbide has an excellent temperature withstanding capability of 1425°C. It is resistant to corrosion and chemical erosion. Modern fusion reactors, Stirling cycle based gas turbines, evaporators in evaporative cooling system for air condition and generator in LiBr/H2O absorption chillers for air conditioning those systems heat transfer rate can be improved by replacing a present heat exchanger with silicon carbide heat exchanger. This review presents a detailed discussion about processing technique of such a silicon carbide. Modern known processing techniques are partial sintering, direct foaming, replica, sacrificial template and bonding techniques. The full potential of these materials can be achieved when properties are directed over specified application. While eyeing over full potential it is highly dependent on processing techniques.

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Frankman, David J., Brent W. Webb, and Matthew R. Jones. "Investigation of Lightpipe Volumetric Radiation Effects in RTP Thermometry." Journal of Heat Transfer 128, no. 2 (July 28, 2005): 132–41. http://dx.doi.org/10.1115/1.2136917.

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A major obstacle to the widespread implementation of rapid thermal processing (RTP) is the challenge of wafer temperature measurement. Frequently, lightpipe radiation thermometers are used to measure wafer temperatures in RTP reactors. While the lightpipe distorts the wafer temperature profile less than temperature measurement techniques which require physical contact, the presence of the lightpipe influences the wafer temperature profile. This paper presents the results of a theoretical study exploring that influence for an idealized RTP reactor in which the wafer is treated as a nonconducting, opaque, constant-heat-flux surface imaged by the lightpipe. The coupled radiation/conduction transport in the lightpipe measurement enclosure is solved numerically. Radiation transfer in the system is modeled with varying levels of rigor, ranging from a simple volumetrically nonparticipating treatment to a full spectral solution of the radiative transfer equation. The results reveal a rather significant effect of the lightpipe on the wafer temperature, which depends on the separation between the lightpipe tip and the wafer. The study illustrates clearly the need to model the lightpipe as a volumetrically participating, semitransparent medium, and further, the importance of accounting for spectral variation of the lightpipe properties in the prediction of the radiative transfer. Finally, two primary mechanisms are identified by which the lightpipe affects the wafer temperature distribution.

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Matějíček, Jiří, Monika Vilémová, Jakub Veverka, Jiří Kubásek, František Lukáč, Pavel Novák, Dalibor Preisler, Josef Stráský, and Zdeněk Weiss. "On the Structural and Chemical Homogeneity of Spark Plasma Sintered Tungsten." Metals 9, no. 8 (August 10, 2019): 879. http://dx.doi.org/10.3390/met9080879.

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Tungsten-based materials are the prime candidate plasma-facing materials for future fusion reactors, such as DEMO. Spark plasma sintering is a prospective fabrication technology with several advantageous features. The concurrent application of electric current, temperature and pressure enhances the sintering process, allowing for lower temperatures and shorter sintering times than traditional powder metallurgy processes. This in turn helps to avoid excessive grain growth and phase segregation in W-alloys. This study is focused on several factors that may influence the homogeneity of the sintered compacts—namely the diffusion of carbon from the graphite die, purity of the powder and sintering conditions. The following characteristics of spark plasma-sintered tungsten compacts were studied: composition (especially carbon and oxygen content), porosity, mechanical properties (hardness and fracture strength), and thermal diffusivity. The effects of the abovementioned processing factors were quantified, and local variations of selected properties were assessed.

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Castelein, Sofie M., Tom F. Aarts, Juergen Schleppi, Ruud Hendrikx, Amarante J. Böttger, Dominik Benz, Maude Marechal, et al. "Iron can be microbially extracted from Lunar and Martian regolith simulants and 3D printed into tough structural materials." PLOS ONE 16, no. 4 (April 28, 2021): e0249962. http://dx.doi.org/10.1371/journal.pone.0249962.

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In-situ resource utilization (ISRU) is increasingly acknowledged as an essential requirement for the construction of sustainable extra-terrestrial colonies. Even with decreasing launch costs, the ultimate goal of establishing colonies must be the usage of resources found at the destination of interest. Typical approaches towards ISRU are often constrained by the mass and energy requirements of transporting processing machineries, such as rovers and massive reactors, and the vast amount of consumables needed. Application of self-reproducing bacteria for the extraction of resources is a promising approach to reduce these pitfalls. In this work, the bacterium Shewanella oneidensis was used to reduce three different types of Lunar and Martian regolith simulants, allowing for the magnetic extraction of iron-rich materials. The combination of bacterial treatment and magnetic extraction resulted in a 5.8-times higher quantity of iron and 43.6% higher iron concentration compared to solely magnetic extraction. The materials were 3D printed into cylinders and the mechanical properties were tested, resulting in a 400% improvement in compressive strength in the bacterially treated samples. This work demonstrates a proof of concept for the on-demand production of construction and replacement parts in space exploration.

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Mokrova, Nataliya V. "Methods of Mathematical Modeling of the Leaching Process of Cobalt-Containing Solutions." Solid State Phenomena 316 (April 2021): 661–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.661.

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Current cobalt processing practices are described. This article discusses the advantages of the group argument accounting method for mathematical modeling of the leaching process of cobalt solutions. Identification of the mathematical model of the cascade of reactors of cobalt-producing is presented. Group method of data handling is allowing: to eliminate the need to calculate quantities of chemical kinetics; to get the opportunity to take into account the results of mixed experiments; to exclude the influence of random interference on the simulation results. The proposed model confirms the capabilities of the group method of data handling for describing multistage processes.

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Lipin, Konstantin V., and Sergey V. Fedoseev. "SEMI-INDUSTRIAL TECHNOLOGY FOR SYNTHESIS OF TETRACYANOETHYLENE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no. 6 (May 13, 2020): 72–79. http://dx.doi.org/10.6060/ivkkt.20206306.6187.

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The goal of our work is to develop a synthesis of tetracyanoethylene suitable for scaling and to design a technological scheme of the process based on it. To achieve this goal, a tetracyanoethylene synthesis method was originally developed, which consists of the following stages: obtaining sodium cyanodithioformate based on carbon disulfide and sodium cyanide using N, N-dimethylformamide as a solvent; obtaining tetracyano-1,4-dithiine by treating sodium cyanodithioformate with chlorine; obtaining tetracyanoethylene from tetracyano-1,4-dithiine by sequential interaction with sodium cyanide and chlorine. The developed method was tested in the laboratory, where it showed its suitability. Therefore, further on the base of this method, a technological scheme of the process was designed. A description of the scheme and the necessary sequence of operations are compiled. The interaction takes place in the reactors R-1, R-2, R-3. Pumps N-1–4 provided the pumping the reaction mass. Also, in the technological scheme there is an F-1 Nutsche filter for separation of the suspension. To isolate and purify the obtained tetracyanoethylene, an I-1 vacuum evaporator and a SA-1 sublimation apparatus are used. The necessary equipment was selected for the technological scheme: Р-1 reactor made of Teflon with a volume of 200 l with a stirrer and a jacket; two reactors Р-2 and Р-3 made of glass with a volume of 200 l with a stirrer and a jacket; Ф-1 Nutsche filter made of thick-walled polypropylene pipes; sublimation apparatus CA-1 continuous. The selection of the main and auxiliary equipment was carried out on the base of the chemical and physico-chemical characteristics of the reagents, technological conditions and the characteristics of the process. This method of obtaining compares favorably with the use of simple and cheap raw materials common in the chemical industry and the use of standard processing equipment.

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Kravchenko, V. V., and S. D. Tsygankova. "Effect of Corrosion of the Fuel Rod Construction Materials on the Radiation Safety of Nuclear Power Plants with PWR." ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 63, no. 1 (February 7, 2020): 89–98. http://dx.doi.org/10.21122/1029-7448-2020-63-1-89-98.

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The article considers the general concept of corrosion in accordance with GOST 5272–68 “Metal Corrosion”, the classification of the corrosion process, the stages of corrosion as energy function of the flow path of the corrosion process, the main indicators of the corrosion process. According to the forecasts of the International Monetary Fund and Focus Economics, the amount of funds that will be spent on counteracting corrosion and its consequences in selected industrialized countries has been estimated. The growth of funds invested in the counteracting the effects of metal corrosion in the Russian Federation for 2016–2019 is presented in the form of a diagram. The substantiation of the use of zirconium as a structural material for the shell of fuel rods has been fulfilled. The values of the thermal neutron absorption cross sections for various elements serving as structural elements for the core of a nuclear reactor are presented. Factors influencing the choice of alloying elements and their percentage in various alloys (Zr-2, Zr-4, ZIRLO™, M5®), which are the special development that reduce the corrosion rate, are also considered. The composition and mechanical properties of E110 and E635 alloys, which were used as materials for the fuel rods shell in the core of WWER-1200 reactors at the Belarusian NPP, are considered as well. The behavior of zirconium alloys E110 and E635 in the core is analyzed. The main factors that make a significant contribution to the corrosion process in actual operating conditions of zirconium alloys as fuel rods shell have been identified. The existing methods of preliminary special processing of fuel rods shells stored in the air for a long time before their receipt for assembly are presented. The structure of the oxide on the shells of alloys E110 and E635 oxidized in an autoclave is demonstrated.

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Prayitno, Prayitno, Sri Rulianah, Windi Zamrudy, and Sugeng Hadi Susilo. "An analysis of performance of an anaerobic fixed film biofilter (AnF2B) reactor in treatment of cassava wastewater." Eastern-European Journal of Enterprise Technologies 1, no. 10 (109) (February 23, 2021): 6–13. http://dx.doi.org/10.15587/1729-4061.2021.225324.

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The cassava starch wastewater contains organic materials (as BOD, COD) in high concentrations so it has the potential to cause pollution in the aquatic environment. Several methods of cassava starch wastewater treatment have been used to reduce the concentration of organic matter (pollutants) in cassava starch wastewater, including Activated Sludge, Stabilization Pond, Anaerobic-Aerobic filter process. However, various studies continue to be carried out to get higher processing efficiency on the factors that influence it. Several factors influence the efficiency of wastewater treatment processes, including the type and origin of decomposing microorganisms, hydraulic residence time (HRT), organic load rate (OLR), process design, pH, and temperature. The research aimed to evaluate the performance of the AnF2B reactor in treating cassava starch wastewater, in which the reactor performance is shown by changes in organic matter removal (COD removal) and biogas production. The research is conducted using 3 types of AnF2B reactors wherein each AnF2B reactor contains a bee nest-shaped bio-filter as a growth medium for the consortium of indigenous bacteria. The AnF2B reactor operates in anaerobic conditions with a set temperature of 29–30 °C and a pH of 4.5–7. In each AnF2B reactor, cassava starch wastewater is fed with different OLR so that each reactor has an HRT of 5, 6, and 7 days. The concentration of COD at the influent and effluent of the reactor was measured and the biogas was produced using the APHA standard method. The results showed that the AnF2B reactor had a satisfactory performance in COD removal and biogas production, which at HRT: 6 days and OLR of 1.72 g/L·day found that the maximum COD removal was 98 % and the volume of biogas of 4.8 L/L·day was produced on the 12th day

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Lock, Irene Sow Mei, Idris B. Ismail, Bawadi Abdullah, and Areeba Shafquet. "Evaluation of Electrical Capacitance Tomography Thresholding Techniques for Void Fraction Measurement of Gas-Liquid System." Applied Mechanics and Materials 625 (September 2014): 439–43. http://dx.doi.org/10.4028/www.scientific.net/amm.625.439.

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An analysis on the void fraction measurement for binary phase gas-liquid dielectric materials inside an Electrical Capacitance Tomography (ECT) sensor has been performed on the tomogram images by using different thresholding techniques. The analysis is pertinent to improve the accuracy of the application of thresholding technique for void fraction measurements in pipelines and reactors since the currently available information is limited in terms of accuracy. This preliminary investigation was performed to evaluate the accuracy of three different thresholding algorithms: Otsu’s, Niblack’s and Kuo’s Method based on the void fraction measurement for a binary phase oil-air system. The experimental and image processing analysis enables one to determine the optimal threshold method by selecting the threshold algorithm which produces the highest accuracy and consistency in the void fraction measurement as compared to the actual value.

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Hahn, Bradley. "PRC Nuclear Energy — Exploration & Exploitation — past developments and future trends." Energy Exploration & Exploitation 7, no. 5 (October 1989): 287–305. http://dx.doi.org/10.1177/014459878900700502.

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Since the 1950's a comprehensive nuclear development program has been in effect. Recently, and especially since 1988 when industrial restructuring brought peaceful uses of nuclear energy into the new Ministry of Energy Resources, there has been increased emphasis on its use for power generating. Proven reserves of uranium are said to be sufficient to fuel pressurized reactors with a total capacity of 15,000 MW for 30 years. By the early 90's China will have 2,100 MWinstalled electrical generating capacity from nuclear sources. Reportedly, capacity is planned to expand to 10,000 MW by the next century. An estimated 25% of the planned output will be with imported equipment. China has comprehensive programs for nuclear materials procressing, enhanced radiation development, irradiation processes, research in physics, aerospace applications and waste processing.

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Gonzalez, Zoilo, Joaquin Yus, Yessica Bravo, Antonio Javier Sanchez-Herencia, and Begoña Ferrari. "Exploitation of Lignocellulose Fiber-Based Biotemplates to Improve the Performance of an Immobilized TiO2 Photocatalyst." Catalysts 11, no. 2 (January 23, 2021): 156. http://dx.doi.org/10.3390/catal11020156.

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The performance of an immobilized photocatalyst has been successfully improved by colloidal processing of a heterostructure composed by TiO2 nanoparticles and lignocellulose nanofibers (LCNFs) obtained from biomass residues. The incorporation of 4 wt.% of biotemplate to the formulation increased the degradation rate and reduced the operating time to remove the 100% of methyl orange of a liquid solution. The reaction rate constant (k = 0.29–0.45 h−1) of the prepared photocatalytic coatings (using commercial particles and templates obtained from natural-derived resources) are competitive with other pure TiO2 materials (no composites), which were prepared through more complex methodologies. The optimization stages of deposition and sintering processes allowed us to obtain homogeneous and crack-free microstructures with controlled thickness and mass values ranging from 3 to 12 µm and 0.9 to 5.6 mg, respectively. The variation of the microstructures was achieved by varying the amount of LCNF in the formulated suspensions. The versatility of the proposed methodology would allow for implementation over the internal surface of photocatalytic reactors or as a photocatalytic layer of their membranes. In addition, the processing strategy could be applied to immobilize other synthetized semiconductors with higher intrinsic photocatalysis properties.

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Kamel, Khaled, and Eman Kamel. "PLC Batch Process Control Design and Implementation Fundamentals." September 2020 2, no. 3 (June 9, 2020): 155–61. http://dx.doi.org/10.36548/jei.2020.3.001.

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Batch process control is typically used for repeated chemical reaction tasks. It starts with a measured liquid material filling operations followed by a controlled reaction leading to the discharge or transport of processed quantities of material. The input materials is contained in vessel reactor and subjected to a sequence of processing activities over a recipe predefined duration of time. Batch systems are designed to measure, process, and discharge a varying volume of liquid from drums, tanks, reactors, or other large storage vessel using a programmable logic controller (PLC). These systems are common in pharmaceutical, chemical packaging, Beverage processing, personal care product, biotech manufacturing, dairy processing, soap manufacturing, and food processing industries. This paper briefly discusses the fundamental techniques used in specifying, designing, and implementing a PLC batch process control [1, 2]. A simplified batch process is used to illustrate key issues in designing and implementing such systems. In addition to the structured PLC ladder design; more focus is given to safety requirements, redundancy, interlocking, input data validation, and safe operation. The Allen Bradley (AB) SLC 500 PLC along with the LogixPro simulator are used to illustrate the concepts discussed in this paper. Two pumps are used to bring in material during the tank filling and a third pump is used to drain processed product. The three pumps are equipped with flow meters providing pulses proportional to the actual flow rate through the individual pipes. The tank material is heated to a predefined temperature duration followed by mixing for a set time before discharge. Batch control systems provides automated process controls, typically and universally using PLC’s networked to HMI’s and other data storage, analysis, and assessment computers. The overall system perform several tasks including recipe development and download, production scheduling, batch management and execution, equipment performance monitoring, inventory, production history and tracking functionalities. Flexible batch control systems are designed to accommodate smaller batches of products with greater requirements / recipes variation, efficiently and quickly. In addition to providing process consistency, continuous batch process control quality improvements are attained through the automatic collection and analysis of real-time reliable and accurate event performance data [3, 4].

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Gabbar, Hossam A., Lingzhi Xia, Manir U. Isham, and Vladimir Ponomarev. "Signal processing system design for improved shutdown system of CANDU® nuclear reactors in large break LOCA events." Nuclear Engineering and Design 298 (March 2016): 255–63. http://dx.doi.org/10.1016/j.nucengdes.2015.12.018.

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Svanström, M., M. Modell, and J. Tester. "Direct energy recovery from primary and secondary sludges by supercritical water oxidation." Water Science and Technology 49, no. 10 (May 1, 2004): 201–8. http://dx.doi.org/10.2166/wst.2004.0644.

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Supercritical water oxidation (SCWO) oxidizes organic and biological materials virtually completely to benign products without the need for stack gas scrubbing. Heavy metals are recovered as stabilized solid, along with the sand and clay that is present in the feed. The technology has been under development for twenty years. The major obstacle to commercialization has been developing reactors that are not clogged by inorganic solid deposits. That problem has been solved by using tubular reactors with fluid velocities that are high enough to keep solids in suspension. Recently, system designs have been created that reduce the cost of processing sewage sludges below that of incineration. At 10 wt-% dry solids, sludge can be oxidized with virtually complete recovery of the sludge heating value as hot water or high-pressure steam. Liquid carbon dioxide of high purity can be recovered from the gaseous effluent and excess oxygen can be recovered for recycle. The net effect is to reduce the stack to a harmless vent with minimal flow rate of a clean gas. Complete simulations have been developed using physical property models that accurately simulate the thermodynamic properties of sub- and supercritical water in mixtures with O2, N2, CO2, and organics. Capital and operating cost estimates are given for sewage sludge treatment, which are less costly than incineration. The scenario of direct recovery of energy from sludges has inherent benefits compared to other gasification or liquefaction options.

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Testani, Claudio, Paolo Emilio di Nunzio, and Ilaria Salvatori. "Manufacturing of ODS RAFM Steel: Mechanical and Microstructural Characterization." Materials Science Forum 879 (November 2016): 1639–44. http://dx.doi.org/10.4028/www.scientific.net/msf.879.1639.

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Ferritic ODS 14Cr steels reinforced by means of Yttrium oxide nanoclusters represent one of the options for future structural applications in nuclear Generation IV reactors. Due to their high tensile properties and resistance to irradiation damage, Oxide Dispersion Strengthened Steels (ODS-S) have been suggested for nuclear fusion applications. The present paper describes the experimental procedure of mechanical alloying, canning and hot extrusion adopted to produce ODS rods. The effect of variations in the processing parameters are also discussed. Hot extrusion has been successfully applied to produce a batch of about 10 kg of ODS steel. Full size ASTM E21 and E8 specimens have been tested from room temperature up to 800 °C. The microstructure characterization of the manufactured materials has been carried out by transmission electron microscopy. Ultimate tensile stress higher than 1350 MPa have been obtained in the as-extruded material and higher than 1100 MPa in samples annealed for 4 hours at 800 °C.

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Roosen, Andreas. "3-D Structures via Tape Casting and Lamination." Advances in Science and Technology 45 (October 2006): 397–406. http://dx.doi.org/10.4028/www.scientific.net/ast.45.397.

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Miniaturisation and multi-functionality are the driving forces in the field of many technical market segments. Ceramic multilayer technology via tape casting and lamination is one of the key technologies to generate complex, highly integrated devices for future applications. The technique offers a tremendous potential for the integration of different materials combined with the possibility to form complex 3-D structures by layered object manufacturing. The ceramic multilayer technology is based on shaping, screen-printing and stacking of individual ceramic green tapes, which are laminated and co-fired. The tapes can offer ferroelectric, piezoelectric and magnetic behaviour, insulating and semi-conducting properties, voltage-, temperature- and atmosphere-dependent resistances, high thermal conductivity, corrosion resistance, or bio inert behaviour. For the integration of additional features like reactors or sensors, the described layered manufacturing method allows to introduce simultaneously microchannels and other cavities. - New developments in processing and in materials concepts are addressed to overcome limitations and to take maximum advantage of this technique. The technique is illustrated considering e.g. microwave circulators for communication, sensors for automotive applications, and piezoelectric actuators as examples, which demonstrate the potential of the technology for the manufacture of highly integrated multifunctional systems.

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Sameh, Abdel-Hadi Ali. "Production Cycle for Large Scale Fission Mo-99 Separation by the Processing of Irradiated LEU Uranium Silicide Fuel Element Targets." Science and Technology of Nuclear Installations 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/704846.

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Uranium silicide fuels proved over decades their exceptional qualification for the operation of higher flux material testing reactors with LEU elements. The application of such fuels as target materials, particularly for the large scale fission Mo-99 producers, offers an efficient and economical solution for the related facilities. The realization of such aim demands the introduction of a suitable dissolution process for the applied U3Si2compound. Excellent results are achieved by the oxidizing dissolution of the fuel meat in hydrofluoric acid at room temperature. The resulting solution is directly behind added to an over stoichiometric amount of potassium hydroxide solution. Uranium and the bulk of fission products are precipitated together with the transuranium compounds. The filtrate contains the molybdenum and the soluble fission product species. It is further treated similar to the in-full scale proven process. The generated off gas stream is handled also as experienced before after passing through KOH washing solution. The generated alkaline fluoride containing waste solution is noncorrosive. Nevertheless fluoride can be selectively bonded as in soluble CaF2by addition of a mixture of solid calcium hydroxide calcium carbonate to the sand cement mixture used for waste solidification. The generated elevated amounts of LEU remnants can be recycled and retargeted. The related technology permits the minimization of the generated fuel waste, saving environment, and improving processing economy.

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PELZER, RAINER, SHARON FARRENS, and DENNIS LEE. "PLASMA ACTIVATED BONDING AND IMPRINTING OF POLYMER BY HOT EMBOSSING FOR PACKAGING APPLICATIONS." International Journal of Nanoscience 04, no. 04 (August 2005): 551–57. http://dx.doi.org/10.1142/s0219581x05003474.

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Hot embossing is a well-acknowledged low cost, high resolution, large area 3D patterning process for polymers. This technique allows rapid prototyping for high volume production of fully patterned substrates for a wide range of thermoplastic polymer materials. The advantages of using polymer substrates over common Micro-Electro-Mechanical System (MEMS) processing materials like glass, silicon or quartz are: bio-compatible surfaces, easy manufacturability, low cost for high volume production, suitable for use in micro- and nano-fabrication, low conductivity, wide range of optical properties just to name a few. The article will present experimental results on HE processes with PMMA, mr-I8030, mr-L6000 and NEB22 on full 8" wafer sizes. Packaging of the imprinted features is a key technology for a wide variety of optical and fluidic applications in the μm and nm-range: m-TAS, micro-mixers, micro-reactors, electrophoresis cells, switches, data storage, etc. Most packaging techniques employed today, use glue material or high temperature sintering methods to bond structured polymer wafers together. These techniques are influencing the appearance of the sub-micron structures. A promising low-temperature polymer-to-polymer direct bonding technique utilizing the cleaning and surface activating behavior of plasma should be established here.

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Maltseva, T., А. Shyshuta, and S. Lukashyn. "Modern Methods of Radiochemical Reprocessing of Spent Nuclear Fuel." Nuclear and Radiation Safety, no. 1(81) (March 12, 2019): 52–57. http://dx.doi.org/10.32918/nrs.2019.1(81).09.

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The paper is devoted to the history of development and the current state of technological and scientific advances in radiochemical reprocessing of spent nuclear fuel from water-cooled power reactors. Regarding spent nuclear fuel (SNF) of NPP power reactors, long-term energy security involves adopting a version of its radiochemical treatment, conditioning and recirculation. Recycling SNF is required for the implementation of a closed fuel cycle and the re-use of regeneration products as energy reactor fuels. The basis of modern technological schemes for the reprocessing of the spent nuclear fuel is the “Purex” process, developed since the 60s in the USA. The classic approach to the use of U and Pu nuclides contained in spent nuclear fuel is to separate them from fission products, re-enrich regenerated uranium and use plutonium for the production of mixed-oxide (MOX) fuel with depleted uranium. The modern reprocessing plants are able to deal with fuel with further increase of its main characteristics without significant changes in the initial project. In order to close the fuel cycle, it is needed to add the following technological steps: (1) removal of high-level and long-lived components and minor actinides; (2) return of actinides to the technological cycle; (3) safe disposal of unused components. Each of these areas is under investigation now. Several new promising multi-cycle hydrometallurgical processes based on the joint extraction of trivalent lanthanides and minor actinides with their subsequent separation have been developed. A number of promising materials is suggested to be potential matrices for the immobilization of high-level components of radioactive wastes. To improve the compatibility of fuel processing with the environment, non-aqueous technologies are being developed, for instance, pyro-chemical methods for the reprocessing of various types of highly active fuels based on metals, oxides, carbides, or nitrides. An important scientific and technological task under investigation is transmutation of actinides. The results of international large-scale experiments on the partitioning and transmutation of fuel with various minor actinides and long-lived fission products confirm the real possibility and expediency of closing the nuclear fuel cycle.

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Journal articles on the topic 'Materials processing reactors'

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