Large scale buffer material test: Mock-up experiment at CIEMAT

2005 ◽  
Vol 81 (3) ◽  
pp. 298-316 ◽  
Author(s):  
P.L. Martín ◽  
J.M. Barcala
Keyword(s):  
Large Scale ◽  
Material Test ◽  
Buffer Material

Mineralogical investigations of the first package of the alternative buffer material test – II. Exchangeable cation population rearrangement

Clay Minerals ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 215-233 ◽  
Author(s):  
R. Dohrmann ◽  
S. Olsson ◽  
S. Kaufhold ◽  
P. Sellin
Keyword(s):  
Cation Exchange ◽  
Large Scale ◽  
Vertical Direction ◽  
Exchange Capacity ◽  
Maximum Temperature ◽  
Exchangeable Cation ◽  
Water Tank ◽  
Material Test ◽  
Buffer Material ◽  
Iron Tube

AbstractBentonites are candidate materials for the encapsulation of radioactive waste. In the ‘Alternative Buffer Material test’ (ABM), compacted ring-shaped blocks of eleven different buffer materials (mainly bentonites) were packed vertically on top of each other with an iron tube as heater in the centre. These buffer materials started with various exchangeable cation populations (ECpopulation). The first ‘ABM package’ was terminated 28 months after installation and the bentonites had been exposed to the maximum temperature (130°C) for about one year. The aim of the present study is first: to describe modification of the cation exchange population, and second to understand the influence of the groundwater on cation exchange at different scales. No significant horizontal variation of any exchangeable cation (EC) was detected between 1 and 7 cm distance from contact with the iron tube. Large total differences of the ECpopulations, however, were observed for the individual blocks after the field experiment (n = 21 blocks) with respect to the composition of the reference materials. The average cation exchange capacity (CEC) values of the analysed bentonites (n = 9 blocks) decreased by 5.5 meq/100 (1.1 – 8.8 meq/100 g) after the experiment. Exchangeable Na+ and Mg2+ decreased on average, whereas Ca2+ increased. This trend was pronounced in the top region of the parcel (upper seven blocks). Although most changes occurred on the large scale of the whole test parcel, small but important changes were also recorded in the vertical direction on the centimetre scale. The observed differences cannot be explained assuming simply that a bentonite reacts only with neighbouring blocks, which would mean that the system was more or less closed. The differences are much larger and the only conclusion from this observation is that the whole package seems to be influenced by the groundwater which was added from a water tank at the experiment site, enabling at least partial equilibration between the different blocks.

Mineralogical investigations of the first package of the alternative buffer material test – I. Alteration of bentonites

Clay Minerals ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 199-213 ◽  
Author(s):  
S. Kaufhold ◽  
R. Dohrmann ◽  
T. Sandén ◽  
P. Sellin ◽  
D. Svensson
Keyword(s):  
Large Scale ◽  
Carbon Accumulation ◽  
Maximum Temperature ◽  
Material Test ◽  
Buffer Material ◽  
Set Up ◽  
One Year ◽  
The Stability ◽  
Iron Tube ◽  
Almost All

AbstractBentonite, which is envisaged as a promising engineered barrier material for the safe disposal of highly radioactive waste, was and is investigated in different large scale tests. The main focus was and is on the stability (or durability) of the bentonite. However, most countries concentrated on one or a few different bentonites only, regardless of the fact that bentonite performance in different applications is highly variable. Therefore, SKB (Svensk Kärnbränslehantering) set up the first large scale test which aimed at a direct comparison of different bentonites. This test was termed the ‘alternative buffer material test’ and considers eleven different clays which were either compacted (blocks) or put into cages to keep the material together. One so-called package consisted of thirty different blocks placed on top of each other. These blocks surrounded a heated iron tube 10 cm in diameter. Altogether three packages were installed in the underground test laboratory Äspö, Sweden. The first package was terminated 28 months after installation and the bentonite had been exposed for the maximum temperature (130°C) for about one year.Almost all geochemical and mineralogical alterations of the different bentonites (apart from exchangeable cations) were restricted to the contact between iron and bentonite. The increase of the Fe2O3 content was attributed to corrosion of the tube. However, the typical 7 or 14 Å smectite alteration product was not found. At the contact of one sample, siderite was precipitated. Some samples showed anhydrite and organic carbon accumulation and some showed dissolution of clinoptilolite and cristobalite. IR spectroscopy, XRD, and XRF data indicated the formation of trioctahedral minerals/domains in the case of some bentonites. Even more data has to be collected before unambiguous conclusions concerning both alteration mechanisms and bentonite differences can be drawn.

Manufacturing and Handling Techniques of the Monolithic Buffer Material for HLW Disposal

2001 ◽  
Author(s):  
Toshihiko Awano ◽  
Takeshi Kanno ◽  
Susumu Kawakami ◽  
Hiroyoshi Ueda ◽  
Takahiro Kimoto
Keyword(s):  
Radioactive Waste ◽  
Large Scale ◽  
Cold Isostatic Pressing ◽  
Large Block ◽  
Technical Feasibility ◽  
Geological Disposal ◽  
Buffer Material ◽  
Manufacturing Tests ◽  
High Level ◽  
Large Scale Tests

Abstract Small and large scale tests were performed to evaluate technical feasibility of the monolithic buffer material, defined as a large block of bentonite formed by the cold isostatic pressing, for geological disposal of high-level radioactive waste. Trial manufacturing tests up to approximately 70 [%]-scale of a Japanese disposal concept were carried out and emplacement tests were carried out by vacuum lifting and forklift-type methods for vertical and horizontal emplacement concepts, respectively. Based on the large engineering-scale tests, technical feasibility of the monolithic buffer was demonstrated.

Modelling coupled processes in bentonite: recent results from the UK's contribution to the Äspö EBS Task Force

2012 ◽  
Vol 76 (8) ◽  
pp. 3033-3043 ◽  
Author(s):  
D. Holton ◽  
S. Baxter ◽  
A. R. Hoch
Keyword(s):  
Large Scale ◽  
Task Force ◽  
Fractured Rock ◽  
Coupled Processes ◽  
Spent Fuel ◽  
Rock Interaction ◽  
Waste Container ◽  
Buffer Material ◽  
The Uk

AbstractA range of potential concepts for the geological disposal of high level wastes and spent fuel are being studied and considered in the UK. These include concepts that use bentonite as a buffer material around the waste containers. The bentonite will be required to fulfil certain safety functions, the most important being (1) to protect the waste containers from detrimental thermal, hydraulic, mechanical and chemical processes; and (2) to retard the release of radionuclides from any waste container that fails. The bentonite should have a low permeability and a high sorption capacity.These safety functions could be challenged by certain features, events and processes (FEPs) that may occur during the evolution of the disposal system. A consideration of how these FEPs may affect the safety functions can be used to identify and to prioritize the important areas for research on bentonite. We identify these important areas (which include hydration of compacted bentonite, illitization and erosion of bentonite), and describe how they are being investigated in current international research on bentonite.The Äspö EBS Task Force is a collaborative international project designed to carry out research on bentonite. In 2011, the Nuclear Decommissioning Authority Radioactive Waste Management Directorate joined the EBS Task Force partly to benefit from its collective experience. The work of the EBS Task Force is split into two research subareas: (1) the THM subarea, which includes tasks to understand homogenization of bentonite as it resaturates, to investigate the hydraulic interaction between bentonite and fractured rock, and to model in situ experiments; and (2) the THC subarea, which includes tasks to investigate the issue of understanding transport through bentonite, and to model in situ experiments. In particular, the bentonite rock interaction experiment is a large-scale in situ experiment concerned with understanding groundwater exchange across bentonite rock interfaces, with the objective of establishing better understanding of bentonite wetting. In this paper, we describe our work to model the spatial and temporal resaturation of bentonite buffer in a fractured host rock.

Developments for in Situ Tests on Compacted Bentonite-Based Buffer Material

1990 ◽  
Vol 212 ◽  
Author(s):  
B. H. Kjartanson ◽  
M. N. Gray ◽  
B.C.M. Pulles
Keyword(s):  
Large Scale ◽  
Large Diameter ◽  
Full Scale ◽  
In Situ Tests ◽  
Buffer Material ◽  
In Situ Experiments ◽  
Buffer Mixture ◽  
Underground Research Laboratory ◽  
Nuclear Fuel Waste

ABSTRACTAECL Research is carrying out large-scale in situ experiments at its Underground Research Laboratory (URL). The Buffer/Container Experiment is designed principally to investigate the full scale, in situ performance of bentonite-based buffer material in a single emplacement borehole environment. In addition, the response of the rock to excavation and heating will be investigated. The experiment also allows for the development of the technologies needed to demonstrate some of the vault engineering activities proposed in the Canadian nuclear fuel waste disposal concept. These include excavation of large diameter boreholes for waste emplacement and in situ compaction of a bentonite/sand buffer mixture. Although these methodologies developed for the URL have not been optimized for the commercial, full-scale operations needed for a disposal vault, results show that the equipment and methodologies needed for vault operations are a reasonable extrapolation of existing technology.

scholarly journals PEMBUATAN MEDIA KARTU SOAL PERHITUNGAN pH PADA MATERI POKOK LARUTAN PENYANGGA Di SMAN 1 JENAMAS

2019 ◽  
Vol 6 (1) ◽  
pp. 77
Author(s):  
Novrian Dony ◽  
Jurniah J ◽  
Herlina Apriani
Keyword(s):  
Research And Development ◽  
Large Scale ◽  
Major Product ◽  
Average Score ◽  
Small Scale ◽  
Public High School ◽  
Research Information ◽  
Initial Product ◽  
Average Value ◽  
Buffer Material

Abstract This study aims to produce learning media in form question card for calculating pH on buffer material in Jenamas 1 Public High School. The media card of this question was made with the Research and Development method through Borg and Gall process steps (R & D) consisting of preliminary research information, planning, initial product development, initial product testing, major product revisions, main product trials, operational product revisions, final product revisions. The results of the feasibility test of the card about the feasibility of content, language, graphics, and presentation by the validator get an average value of 98.6% with a very feasible ratio. In just a small scale trial the average score is 16.9 with a very good category, while for large scale the average score is 19.6 with a very good category. Use it from the search for the situation above so that card media from abroad can be represented as learning media. Keywords: Learning Media; Question Card; Media Feasibility Abstrak Penelitian ini bertujuan untuk menghasilkan media pembelajaran kimia berupa kartu soal untuk perhitungan pH pada materi larutan penyangga di SMA Negeri 1 Jenamas. Media kartu soal ini dihasilkan dengan metode Penelitian dan Pengembangan (Research and Development) menurut Borg and Gall melalui langkah – langkah proses ( R & D ) terdiri dari penelitian awal pengumpulan informasi, perencanaan, pengembangan produk awal, uji coba produk awal, revisi produk utama, uji coba produk utama, revisi produk operasional, revisi produk final. Hasil uji kelayakan media kartu soal kelayakan isi, bahasa, kegrafisan, dan penyajian oleh validator mendapatkan skor rata – rata sebesar 98,6% dengan kriteria sangat layak. Pada uji coba skala kecil mendapatkan rata – rata skor sebesar 16,9 dengan kategori sangat baik, sedangkan untuk skala besar mendapatkan rata – rata skor sebesar 19,6 dengan kategori sangat baik. Berdasarkan dari hasil penelitian diatas maka dapat disimpulkan media kartu soal layak digunakan sebagai media pembelajaran. Kata Kunci : Media Pembelajaran; Kartu Soal;Kelayakan Media

Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1

1999 ◽  
Vol 173 ◽  
pp. 243-248
Author(s):  
D. Kubáček ◽  
A. Galád ◽  
A. Pravda
Keyword(s):  
Image Processing ◽  
Large Scale ◽  
Harvard College ◽  
Oak Ridge ◽  
Large Scale Structures ◽  
Short Period Comet ◽  
Short Period ◽  
Scale Structures ◽  
Harvard College Observatory ◽  
Period Comet

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

Evolution of Large-Scale Coronal Structures

1994 ◽  
Vol 144 ◽  
pp. 29-33
Author(s):  
P. Ambrož
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Large Scale ◽  
Coronal Magnetic Field ◽  
Source Surface ◽  
Solar Cycles ◽  
Characteristic Relationship ◽  
The Magnetic Field ◽  
Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

Large-scale Motion of Solar Filaments

2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll
Keyword(s):  
Magnetic Flux ◽  
Proper Motion ◽  
Time Scale ◽  
Large Scale ◽  
Accuracy Of Measurements ◽  
Solar Filaments ◽  
General Movement ◽  
Scale Motion ◽  
Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

Some applications of electron beam microanalysis techniques in VLSI process evaluation

1983 ◽  
Vol 41 ◽  
pp. 160-161
Author(s):  
Simon Thomas
Keyword(s):  
Integrated Circuits ◽  
Process Evaluation ◽  
Large Scale ◽  
Technology Development ◽  
Analytical Techniques ◽  
Successful Implementation ◽  
Analysis Of Failures ◽  
Characterization Of Materials ◽  
Circuits Vlsi

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.

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