May, 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Contents:

Topics: What’s New in the World of Superconductivity
Feature Article: Advancements in Superconducting Industrial Equipment
Technology-Trends in Superconducting Industrial Equipment Technology-High-Temperature Superconducting Motors for Ship Propulsion Systems-Decontamination Technology for Naturally Occurring Soil Contamination Using
Superconducting Magnets-Development of Superconducting Magnets Designed for Magnetic Field Characteristic
Measurements-The Current Status of Superconducting Heating Furnace

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Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan
Tel:+81-44-850-1612, Fax:+81-44-850-1613
Top of Superconductivity Web21: http://www.istec.or.jp/web21/web21-E.html
This work was subsidized by JKA using promotion funds fromKEIRIN RACE
http://ringring-keirin.jp

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

What’s New in the World of Superconductivity초전도 뉴스 –세계의 동향超电导新闻-世界的动向-chāo diàn dǎo xīnwén

- shìjiè de dòngxiàng-

Yutaka Yamada, Principal Research Fellow
Superconductivity Research Laboratory, ISTEC★News sources and related areas in this issue►Power Application

전력응용电力应用 [diànlì yìngyòng]RWE and Nexans Form Agreement for the Superconductor System
Nexans (12 March, 2015)
Nexans, RWE Deutschland AG and RWE Netzservice GmbH signed an agreement to exclusively market acost-effective and innovative solution to meet the rising demand for electricity by selling superconducting
power equipment system concept in Germany and other countries. The joint agreement between Nexans
and RWE is made under a common project named “AmpaCity”, which is funded by the German Federal
Ministry for Economic Affairs and Energy. The system allows large high-voltage substations be removed
from city centres and replaced with more compact medium-voltage systems, thus freeing up spaces forother urban developments.
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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
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KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Frank Schmidt, Head of the Nexans Superconductor Activity is quoted as saying, “The rising demand forenergy in urban areas, combined with the fact that space is an expensive asset in these locations, forces
the move to powerful, space-saving electricity transportation.” The technology has been developed andindustrialised by Nexans over the last 15 years and thus the aim is to exploit the technological knowledge
attained to advance customer projects in order to optimise the superconductor system as a whole.
Klaus Engelbertz, Managing Director of RWE Netzservice GmbH, states, “We have shown that thesuperconductor system concept is an innovative technology that has proven its practicality and suitability fordaily use. From an economic perspective too, the superconductor can also represent a genuine alternative
to conventional grid expansion. RWE and Nexans combine the necessary areas of expertise andexperience to offer customers a suitable solution portfolio. These customers may require anything from acustomised feasibility study right up to an entire superconductor system.”
Source:”RWE and Nexans form exclusive joint agreement to promote the superconductor system concept
to supply more energy to densely populated urban areas”(12 March, 2015)
Press Release
http://www.nexans.de/eservice/Germany-en/navigatepub_148782_-34273/RWE_and_Nexans_form_exclu
sive_joint_agreement.html
Contact: Jutta van Bühl, jutta.van_Buehl@nexans.com

SFCL in Augsburg Grid
Siemens (31 January, 2015)
Siemens is to install it’s first single three-phase resistive superconducting fault current limiter (SFCL) in
Stadwerke Ausburg’s medium-voltage power grid, under a project called ASSiST, which is sponsored by
the Bavarian State Ministry for Economic Affairs and Media, Energy, and Technology, as part of the German
government’s Innovative Energy Technologies and Energy Efficiency (BayINVENT) Program.
The SFCL will have a rated current of 817A, incorporating 2G HTS tape provided by AMSC, and providing
a connection between Stadtwerke Augsburg’s grid and an industrial company. An energy load with amaximum feed-in power of 15 MWt will be fed from the company’s grid into Stadwerke’s grid. Development
and installation are to be completed by the fall of 2015. Siemens aims for a permanent installation after theformal completion of the project.
In normal operation, up to 1,100 MWt of electricity are lost worldwide due to the use of SCLRs, which havebeen the standard industry method for handling short circuits. Siemens notes that these losses could be
reduced by 50 % or more through the use of SFCLs, even considering the energy they require for cooling
purposes.
Source: ”Siemens to Install SFCL in Augsburg Grid”
Superconductor Week (31 January, 2015)

MgB2 Wind Turbine in Australia
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May 2015

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University of Wollongong (31 December, 2014)
A research group based at University of Wollongong (UOW), in collaboration with Hyper Tech Research,
Inc., is developing offshore wind turbines using MgB2 coils for a direct drive generator that they anticipatedwill offer greater efficiencies at approximately one-third of the price of other proposed superconducting
models, eliminating the need of a turbine gearbox. This superconducting technology would reduce the size
and weight of the generator by 40 %.
The aim of the project is to construct offshore superconducting 10 MW wind turbine systems (tower,
generator, blades, and power electronics) for less than AU$15 million ($12.4 million). The project is fundedby the Australian Research Council under the Discovery Early Career Researcher Award (DECRA)
program.
Shahriar Hossain, leading researcher at the Institute for Superconducting and Electronic Materials at UOW
is quoted as saying, “Hyper Tech is a longstanding partner and they are happy to work with us. We are also
negotiating with the Korea Basic Science Institute (KBSI) and Korean industry. If government and industry
support is available, then it will be possible to install machines within five years.” He also commented, “Thefuture projected cost of AU$1 to AU$2/meter ($0.80 to $1.6/meter) for MgB2 can be compared to the future
projected cost of AU$20 to AU$25/meter ($16 to $20/meter) for HTS. Nb-based low temperature
superconductors might be a good option but cannot operate without liquid helium, which is becoming
costly.”The UOW team plans to sell the generators at AU$3 to AU$5 million ($2.5 to $4.1 million) each. The
approximate amount of superconductor wire required for the rotor coils of a direct drive 10 MW generator
ranges between 50 to 200 km depending upon the wire or tape size and Ic capabilities. Estimating a
projected requirement of 200 km of YBCO-type conductor, the cost maybe as high as AU$4 to AU$5 million($3.2 to $4.1 million). Hyper Tech projects that the same 200 km length of MgB2 superconducting wire will
cost about AU$200,000 to AU$400,000 ($164,000 to $328,000) within five years.
Source: ”UOW Designing Inexpensive MgB2 Wind Turbine”
Superconductor Week (31 December, 2014)►Basics기초 基础[jīchǔ]High Magnetic Fields to Probe HTSC Theory
Los Alamos National Laboratory (26 March, 2015)
Researchers based at Los Alamos National Laboratory are exposing high-temperature doped copper-oxide
superconductors to very strong magnetic fields in excess of 90 T, modifying the superconducting transition
temperature. An unresolved problem in the field of high-Tc superconductors has been to understand what
drives the high-Tc’s in these materials and whether this occurs at a quantum critical point, where quantum
fluctuations lead to strong electron-electron interactions.

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May 2015

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Brad Ramshaw, the lead researcher on the project, is using the world-record high magnetic fields available
at the National High Magnetic Field Laboratory (NHMFL) Pulsed Field Facility, based in Los Alamos in orderto “pave the way to a new theory of superconductivity.”
High-temperature superconductors, such as yttrium barium copper oxide (YBa2Cu3O6+x), cannot be
explained with BCS theory. By optimally doping YBa2Cu3O6+x, the researchers found that the electrons
move around in a correlated way. “This tells us that the electrons are interacting very strongly when thematerial is an optimal superconductor,” said Ramshaw. Proof of a quantum critical point has yet to be found,but if it can be shown then this would constitute a significant milestone toward resolving thesuperconducting pairing mechanism. The Los Alamos team measured magnetic quantum oscillations as afunction of hole doping under strong magnetic fields in excess of 90 T, enabling quantum oscillations to bemeasured very close to the maximum in the transition temperature Tc ~ 94 K. The research findings showthat there is a strong enhancement of the effective mass at the optimal doping point, which signifies
increasing electron interaction and potentially the quantum critical point. The broken symmetry responsible
for this point has yet to be pinned down, although a connection with charge ordering appears to be likely,
Ramshaw notes.

Source: ”Using magnetic fields to understand high-temperature superconductivity”(26 March, 2015) Press Release
http://www.lanl.gov/discover/news-release-archive/2015/March/03.26-high-temperature-superconductivity.p
hp
Contact: Nancy Ambrosiano, nwa@lanl.gov►Management and Finance 경영정보经营信息[jīngyíng xìnxī]HTS Customer Increased to 31
Superconductor Technologies Inc. (11 March, 2015)
Superconductor Technologies Inc. (STI) reported results for the quarter and year ended December 31,
2014. Jeff Quiram, STI's president and chief executive officer, stated, "During 2014, we achieved key
milestones in wire performance, customer development and deployment of high capacity production
equipment. These important accomplishments position STI to complete the customer qualification activities
necessary to secure commercial customer agreements and to then produce Conductus® wire on acommercial scale in the coming months."
STI's fourth quarter 2014 net revenues were $82,000 compared to $86,000 in the third quarter of 2014 and$150,000 in the fourth quarter of 2013. Revenue for all periods was mainly from legacy wireless products.
Net loss for the fourth quarter 2014 was $2.8 million, compared to a net loss of $2.4 million in the third
quarter of 2014, and a net loss of $3.9 million, in the fourth quarter of 2013. Net revenues for 2014 were$632,000, compared to $1.7 million for 2013. The net loss for 2014 was $8.3 million, compared to $12.2
million for 2013. As of December 31, 2014, STI had $1.2 million in cash and cash equivalents.

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May 2015

Date of Issue: May 15, 2015

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During the quarter STI shipped Conductus wire to nine customers: four new and five existing. Of thesecustomers, six are in Stage 1 evaluation, which includes wire characterization and performance testing, andthree are in Stage 2, which involves significantly more rigorous testing to simulate devices for commercial
deployment. At the beginning of March 2015, STI successfully shipped 500 Amp Conductus wire as part of
the high power superconducting cable demonstration project, which aims to utilize many strands ofConductus wire in a live test environment. Global electrical equipment companies are selling SFCLs topower utilities. The transition from pilot production to full production will enable STI to meet the industry
challenges of price, performance and availability facing the HTS wire market today. Doubling customer
count from 15 to 31 during 2014 expanded the company’s customer base.

Source:”STI Reports 2014 Fourth Quarter and Year-End Results”(11 March, 2015) Press Release
http://phx.corporate-ir.net/phoenix.zhtml?c=70847&p=irol-newsArticle&ID=2024521
Contact: Cathy Mattison or Kirsten Chapman, invest@suptech.com

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Feature Article: Advancements in Superconducting Industrial
Equipment Technology-Trends in Superconducting Industrial Equipment Technology
Yutaka Yamada, Principal Research Fellow
Superconductivity Research Center/ISTEC
The on-going development of a variety of superconducting equipment designed for industrial applications
has led to some noteworthy achievements. For example, JR Tokai has made commercial operational plansof maglev trains travelling between Tokyo and Nagoya from 2027. The media has reported that construction
has already started and steady progress has been made towards commercial operation. For clinicalapplications, trials utilizing superconductor technology have been focused on heavy-ion cancer therapy
systems in addition to conventional MRIs. The author herewith introduces some recent progress ofindustrial equipment, omitting those that are published as feature articles in this Web21 issue.
High temperature superconducting motors feature as a promising technology that can reduce motor losses,
which account for more than 60 % of the electrical power consumed by industrial sectors. Initially, researchand development was mainly advanced by the USA and aimed at large scale motors for industrial use.
Later, the focus shifted towards low speed, high torque motors for ship propulsion systems with thedevelopment and experiments for large-scale motors undertaken in USA, Germany, Japan and Korea. In
Japan, Kawasaki Heavy Industries and the Tokyo University of Marine Science and Technology haveactively led R&D for ship propulsion motors over the past few years. For such particular applications, a
prototype superconducting motor utilizing Bi-based wires has been fabricated and tested, successfully
realizing a high efficiency of 98 % and with specifications of 3 MW of output power and 160 rpms 1).
Professor Nakamura, based at Kyoto University and Sumitomo Electric Industries, has been also working
on superconducting motors for the next-generation electric vehicles.
Whilst the above-mentioned maglev train employs low temperature superconductors for its operation, theRailway Technical Research Institute has been investigating coils fabricated from Y-based wires for maglev,
DC power feeder and flywheel applications. Furukawa Electric has successfully fabricated a Y-based coilapplicable to the flywheel 2). Future plans involve integration trials with a mega solar power plant, which will
be newly constructed at Komekurayama, Yamanashi prefecture in 2015.
Industrial applications involving renewable energies have been actively pursued by Europe and USA in
particular over the past few years. The application of superconductor technology in this field has beenstudied as a route for large power generation by utilizing large-scale wind turbines. Large-scale windturbines exceeding 10 MW (2 MW max of current commercial wind turbines) have a detrimental
mechanical drawback in their design and operation since they have to support the weight of a generator
mounted at the top of the turbine, which can be over several hundred tons. The use of superconductor
technology would significantly reduce the weight of the generator and therefore make it more compact. In
Europe, the development of superconducting wind turbines have been launched under projects named,
SupraPower and InnWind, (10-20MW-class superconducting wind turbines have been investigated, withparticipation by Siemens etc). In Japan also, in 2013, NEDO led a project entitled “Advanced PracticalMay, 2015© ISTEC 2015 All rights reserved.

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Research and Development of Wind Power Generation/Research on Over 10MW-Class Wind Turbines
Generators (AIST etc)” 3). The project aims to fabricate a power generator comprising Y-based wires andthe utilization of iron core can reduce the volume of wires required. Future potential points to a 50 %reduction in size/weight compared to a normal conducting generator and costs reduced to more practicallevels 3).
A new concept of renewable energy applications has also arisen, referred to as wind heat power. For further
details of this technology please refer to the article by Okazaki, ISTEC, in latter part of this Web21 issue.
Wind heat power systems stores the energy derived from wind power by transforming energy to heat. By
exploiting superconductor technology in the heat storage tank of the system, a superconducting coil could
enable greater heat storage at high temperatures in excess of 600 °C, leading to a significant efficiency
enhancement.
Professor Nishijima based at Osaka University, has studied superconducting magnetic separation. During
the past several years, on site demonstration trials have been conducted to verify the effectiveness ofmagnetic separation technology in actual contaminated sludge in Fukushima.
As mentioned in this article, the range of superconductor applications has broadened remarkably leading togreater anticipation for their effectiveness in potential industrial applications. In particular, the utilization ofrenewable energies is currently an issue imposed upon us. The author believes that superconductor
technology has significant potential to contribute to the future society.
References:
1) NEDO Research Outcome for the Development of Ship Propulsion Motor System
http://www.nedo.go.jp/library/seika/shosai_201405/20140000000056.html
2) Furukawa Electric Press Release “Successful Development of a High Temperature Superconducting
Magnet for Next Generation Flywheels”
https://www.furukawa.co.jp/what/2014/kenkai_140310.htm
3) AIST R&D on High Temperature Superconducting Large-scale Wind Turbines
https://unit.aist.go.jp/energy/event/20140305/proc/B2.pdf
http://semrl.t.u-tokyo.ac.jp/supercom/128/128-2.html

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May 2015

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Feature Article: Advancements in Superconducting Industrial
Equipment Technology-High-Temperature Superconducting Motors for Ship Propulsion
Systems
Mitsuru Izumi, Professor
Department of Marine Electronics and Mechanical Engineering
Tokyo University of Marine Science and Technology
Electric propulsion ships offer superior advantages including reduced environmental impact, better
economic prospects, ship maneuverability, safety, less vibration and greater energy savings. Thesebeneficial characteristics have been actively applied to research vessels, tankers and cruise ships, and theirmarket diffusion has been trialed in Japan. Prospective electric motor ship propulsion systems haveconceptually been DC motors and unipolar machines, in addition to induction and synchronous machines.
Here, key technological developments have dedicated at constructing compact and lightweight motors withhigh torque densities, power output densities and greater efficiencies at low-load operations, all attained byelemental development in high temperature superconducting field poles 1).
A 36.5 MW synchronous motor designed for ship propulsion systems, developed by AMSC in USA and a 4
MW-class ship propulsion motor (HTS III) developed by SIEMENS in Europe, have both led in full powersystem/load testing and long-term durability testing trials.
With recent heightened interest in ocean development engineering, the expectation has again focused onsuperconducting motors which can deliver energy savings and also compact propulsion systems that canbe utilized for work/offshore vessels and icebreakers used in offshore oil and gas development. Kawasaki
Heavy Industries have developed racetrack coils employing bismuth-based wires, producing a 3 MW,
160-rpm radial-gap superconducting synchronous motor 2). Present efforts are focused on practicalapplications, undertaking trials using ground-based facilities, determining performance characteristics forcoil applications and establishing power output performance attributes 3). Research on the fabrication of a
prototype system with large-scale output characteristics is necessary to demonstrate the remarkableadvantages afforded by superconducting motors for ship propulsion systems. In Japan, research has
progressed towards systems having greater outputs, and JST’s Strategic Promotion of Innovative
Research and Development (S-innovation) program has led the way with demonstration studies conducted
for key technological components to establish 20 MW-class large output superconducting synchronousmachine. The key technological components demonstrated in the program include robust high-temperature
superconducting coils and their associated protection measures and thermosiphon-type rotor coolingsystems 4). As mentioned above, the numbers of developmental cases undertaken by both Japan andoverseas have increased. The author believes that R&D will become more influential in defining thereliability and safety of large-output propulsion systems, whilst further research is continuously dedicatedtowards the design of high temperature superconducting motors and associated technologicalcomponents.

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References:
1. Mitsuru Izumi, Progress in Technology Development for Superconducting Motors Designed for Ship
Propulsion Systems
http://www.istec.or.jp/web21/pdf/13_03/all.pdf
2. Kawasaki Heavy Industries, Ltd.(2013)
http://www.khi.co.jp/english/pressrelease/detail/20130529_1e.html
3. Tamami Oryu, Current Development of Superconducting Motors for Ship Propulsion Systems, “Electrical
Propulsion Ship; Present Status and Future Technological Trends” at the Tobu Branch Workshop, The
Japan Society of Naval Architects and Ocean Engineers, 10 Dec, 2014
4. Osami Tsukamoto, Development of Key Hardware For Large-scale Superconducting Rotating Machines,
JST Symposium for Strategic Promotion of Innovative Research and Development Program, Creation ofAdvanced Energy/Electronics Industry by Superconducting Systems”, 15 Dec, 2014

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Feature Article: Advancements in Superconducting Industrial
Equipment Technology-Decontamination Technology for Naturally Occurring Soil
Contamination Using Superconducting Magnets
Shigehiro Nishijima, Professor
Graduate School of Engineering, Osaka University
Kajima Corporation has established a novel decontamination technology employing a superconducting
magnetic separation system, able to segregate naturally occurring arsenic contaminant in wasted soil at theshield tunneling construction. The author regards this technology as significant and is therefore introduced
herewith.
Recent years has seen problematic pollution due to naturally occurring heavy metal contaminants in
wasted soil at construction sites. Future construction plans expected to get underway include undergroundrailways/roads and the Tokyo Olympics taking place in the capital city, in addition to large-scale construction
projects such as the Chuo maglev in the near future. It is therefore projected that naturally occurring
contaminated soils will pose challenging problems for environmental remediation in the future. Here, heavy
metals are defined in the Environment Quality Standards for Soil Pollution as cadmium, lead, hexavalentchromium, arsenic, mercury, copper, selenium, fluorine, boron etc. Arsenic, fluorine, and boron are
categorized as heavy metals even though they are not chemically metals as such 1). So where do theseheavy metals originate? Compared with the elemental composition of the entire continental crust, the meanvalue measured at the upper crust of the Japanese islands is mainly lead and arsenic. However, zinc, leadand arsenic dominate the mean values measured from river sediments 2). The Japanese islands havevolcanoes/hot springs and mine/ore deposits signifying the potential existence of naturally occurring heavy
metals. The mines generate arsenic, cadmium, lead etc., whilst hot springs generate boron and arsenic.
Granite and serpentine generate fluorine and chromium, respectively. Seawater generates boron andfluorine, whilst marine sediments generate arsenic, lead, and fluorine 3). Thus, the possibility exists for theentire Japanese archipelago to be potentially contaminated with naturally occurring heavy metals.
Reference 2 shows the vital fact of how arsenic, lead, mercury, cadmium and chromium are dispersed
throughout Japan, proving that it is fundamentally widespread 2).
There were 31 out of 78 actual cases where heavy metal contamination was deemed as naturally occurring(case studies taken in October 2002) 4), with arsenic as the majority contaminant, followed by lead, fluorineand mercury. These results may not reflect the entire situation of Japan since the four types of contaminants
namely; arsenic, lead, fluorine and mercury are common and occur naturally. Based on the numbers of
districts requiring action and categorized by specific toxic substances in FY2012 5), which includes
anthropogenic cases, the numbers of unacceptable (pollution) heavy metal contamination cases (type 2),
includes cadmium, lead and mercury making up over 80 % of the total pollutants. It is therefore understoodthat the high frequency of soil contamination is due to heavy metals.
There are two kinds of Environment Quality Standards for Soil Pollution, namely, soil elution standards andMay, 2015© ISTEC 2015 All rights reserved.

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soil content standards. Naturally occurring heavy metal contaminated soils actually exceed the soil elution
standards 6). Some cases involving arsenic exceed the soil elution standards when measured in
sedimentary rocks, alluvium coastlines and diluvial plains, where the arsenic contamination level is notconsidered high (less than soil contents standard) 2). The Japan Soil Treatment Association estimates thatby 2022 the volume of naturally occurring heavy metal contaminated soil required to be decontaminated will
be around 3~5 million tons annually 7). The author summarizes the above mentioned herewith, i) potential
problems associated with naturally occurring heavy metal contaminated soil in Japan nationwide, ii) arsenic,
lead, fluorine and mercury can be problematic, iii) it is necessary for construction works to meet soil elution
standards, and iv) the expected large volumes of potentially contaminated soils to be remedied.
With these issues in mind, Kajima Corporation and MS Engineering have jointly developed asuperconducting magnetic separation system designed to decontaminate naturally occurring arsenic 8). The
technique extracts arsenic (and lead) contained within industrial sludge at construction sites by a shield
method. Conventionally, this waste goes through a decontamination process utilizing coagulation methodby precipitating out the contaminated soil and heavy metal as a dehydration cake. Cleaning contaminatedsoils by this method is extremely expensive, because of large volumes of contaminated soil to be treated.
Additionally, there are demand constraints issues with intermediate treatment plants such as controlled
landfill sites and cement factories. The new method developed here is able to address such shortfalls. The
method involves mixing the sludge with Fe powder, which acts as an arsenic absorbent, and thenmagnetically separating the arsenic-iron powder using superconducting technology. The Fe powder(particle diameter about 120 ), which is injected into the sludge absorbs the eluted heavy metal ions fromthe soil. The mechanism is explained as follows. The oxidized arsenic close to the ground surface becomespentavalent arsenic ions 9). These ions are anionic H2AsO4- or HAsSO42- in the pore water with a soil pH of
4~8 1). The understanding is that Fe powder dissolved in water forms Fe ions, which reattach to the surfaceof the Fe powder as a hydroxide, thereby capturing arsenic ions in the process. Soil decontamination using
this method has actually confirmed that soil elution standards were met in 150 m3 contaminated soil.
Next, an important issue is to recover the Fe
powder that is absorbed by this heavy metal ion.
Here, superconducting magnetic separation
was employed to effectively recover the Fe
powder from the sludge. When the Fe powder
was suspended at approximately 30 % of thesoil weight, with the As elution density reduced
to around 1/10, with actual measurements
confirmed to be 0.092 mg/L max before
treatment and <0.005 mg/L after treatment.
(Environmental elution standard of As and As
compounds are set as 0.01 mg/L.) However, a
key technological requirement of this novel
method was to enhance the recovery rate of the
Fe powder because of the large volumes of Fe
powder required. Figure 1 shows an outline
view of the system. The installation of aMay, 2015

Fig. 1 The Superconducting Magnetic Separation
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magnetic filter outside of superconducting magnet is required for the purpose of high volume remediation.
The magnetic field domain close to the magnetic filter therefore broadens although the magnetic fieldstrength is low at around 0.2 T. Favorable recovery rates (over 99.9 %) and high throughput (over 60 m3/h)
are realized. The recovery rate was realized with 10~20 mnts of contact time of the Fe powder with thesludge. Also, it was confirmed that the Fe powder did not experience degradation in performance even after
recycling it 75-times. The author sees that the results could vary depending on the density of the targetedsludge. However, it is clear that the Fe powder can be recycled several times in case of naturally occurring
arsenic elution density. (The saturation of Fe absorbent is considered as around 0.5~1.0 g/kg).
In addition to this technique other competing technologies have been proposed and include a centrifugal
separator to recover Fe powder and magnetic separation by permanent magnets etc. Whilst we shouldclosely watch these emerging technologies and whether they become mainstream techniques of the future,
the author highlights the considerable advantages afforded by utilizing superconductor technology, which
can process large volumes of contaminated soils.
References:
1. Shin-Ichiro Wada, Dynamics of Heavy Metals in Soils and its Global Environment 15 (2010)15-21
2. Homepage on Recycling by Ministry of Land, Infrastructure, Transport and Tourism – Press release,standards, manuals, Countermeasures act manual for naturally derived heavy metal contaminant rock/soils
during construction works
3. Japan Gas Appliances Inspection Association HP, Investigation of Soil contamination and the necessary
countermeasures
4. Ministry of the Environment HP, Methods and justification to determine whether or not soil contaminationis specified as naturally occurring poisonous material. Appendix-3
5. Ministry of the Environment HP, Implementation of soil contamination countermeasures acts, soil
contaminant studies and results from countermeasure cases undertaken in FY2012
6. Chihiro Inoue, Elucidation of Form Change of Naturally Derived Heavy Metal Soil Contaminants in theEnvironment, Research conclusions of the Environment Research and Technology Development Fund
FY2013 5B-1107
7. Environmental News 2014/10/22
8. Keijiro Ito, Junichi Kawabata, Takefumi Niki, Application of Iron Powder and Magnetic Separation to
Extract Arsenic from Muddy Water, The 20th Research Meeting on the groundwater/soil contamination andtheir protection measures (2014)S1－03
9. Chemicals Evaluation and Research Institute, Japan, CERI Hazard Assessment Reports: Arsenic and its
inorganic compounds (2008)

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Feature Article: Advancements in Superconducting Industrial
Equipment Technology-Development of Superconducting Magnets Designed for Magnetic Field
Characteristic Measurements
Takeshi Kato, General Manager
Superconductivity Technology Division,
Sumitomo Electric Industries, Ltd.
B-H curve tracers 1) and vibrating sample magnetometers (VSM) 2) are currently employed for scaling
magnetization characteristics. There are several issues associated with such conventional systems andinclude, ① an iron-core type normal conducting coil cannot measure a high-coercive magnet, ②measurements utilizing pulsed magnetic fields are significantly influenced by eddy currents, and ③ theextensive measurement time taken by conventional superconducting magnets.
To address such issues, the author and his research team have developed a cryocooled superconducting
magnet system 3) that utilizes DI-BSCCO wires. The weight of the system has been successfully reduced to
1/4 that of a conventional system, and also the dimensions have been significantly downsized by 1/5,
having 0.8 m depth, 0.3 m width, and 0.3 m height. Furthermore, greater magnetization/demagnetization
speeds of 6T/30 seconds have been attained, which is around a 20 % improvement from the current recordof 5T/30 seconds realized by a conventional system. The system has been developed taking into accountpotential applications where magnetic characteristic measurements are performed as part of the inspection
process of a permanent magnet. Other prospective applications include hard disk inspection systems andmanufacturing lines such as in-field heating furnaces.

【Summary of a superconducting magnet system】
Model
Field Strength
Room temperature bore diameter
Magnetization/demagnetization
speedsOperating current
InductanceField homogeneity
Dimension
WeightMay, 2015

DI-BSCCO-MS 6 T-70
±6 T
Φ70 mm
6 T/30 sec.
250 A
About 1 H
0.3 %/10 mmDSV
0.8 m×0.3 m×0.3 m
About 100 kg© ISTEC 2015 All rights reserved.

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Figure 1 shows the data attained by repeated high-speed magnetization/demagnetization process.
Although AC losses due to repeated magnetization/demagnetization increases the coil temperature, stable
operation is confirmed since the large temperature margins due to high critical temperatures do not trigger
superconducting quenching, a typical characteristic of a high temperature superconductor. Additionally,various operations can be realized here for example when the cryocooler stops operation; there is novibration due to the cryocooler during the magnetization/demagnetization process. Initial cooling of themagnet developed takes around 14 hours. If this was switched on before going home on the previous day,the operation will be ready the following morning. The short time cooling makes possible for coolingwhenever required.

Magnetization (emu)Figure 2 shows an example of a VSM measurement, demonstrating the clear BH loop trace for a small
sample such as a pencil tip. Precise measurements were successfully made in around 6 minutes ofmeasuring time, which is remarkably quicker compared to the conventional systems.

Magnetic field (O e)Fig. 1

Fig. 2 An example of a VSM measurement
performed at Toei Industry Co., Ltd.
(SmCo micro piece)

Reference:(1) http://www.j-ndk.co.jp/product/jikisokutei/bh_curve_tracer.html#sub_03(2) http://www.toeikogyo.co.jp/products/sei-01/vsm-5hsc.html(3) http://www.sei.co.jp/super/magnet_coil/system.html#6t

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

Feature Article: Advancements in Superconducting Industrial
Equipment Technology-The Current Status of Superconducting Heating Furnace
Toru Okazaki, Director
Public Relations Division/International Affairs Division
ISTEC
1. Induction heating furnace
There are superconductor technology and heating furnace. A high-temperature heating furnace employing
superconductor technology requires cryogenic cooling, and current thinking automatically assumes thatsuch furnaces are not compatible even with “high-temperature superconductors (-200 °C)”. However, thistechnology has actually reached a stage prior to potential industrial commercialization. The author provides
a summary and the current status herewith.
Aluminum extrusion manufacturing requires a columnar aluminum block as the raw material. The block isinserted into an extruding machine and shaped similar to extruding pasta. The block however, solidifies atroom temperature and therefore a huge extruding machine is required. Here, heating to the necessary
temperature before melting makes the block softer, thus making extrusion easier. A conventional heatingprocess employs either gas or induction heating. Whilst gas-heating facilities are relatively cheap, thedownside is the long time it takes to heat and therefore running costs are higher due to poor energy
efficiencies.
Induction heating utilizes the electromagnetic induction phenomenon, similar principle to an IH cooking
heater that you find in homes. An IH cooking heater is heated using AC field generated from the coil,“typically” achieving high heat efficiencies. However, just like an aluminum frying pan is not suitable for IH
cooling heater, industrial induction heating is not compatible with heating aluminum. Aluminum and copper
exhibits a similar level of resistance as the coil, and thus the same degree of heating as the metal blockwithin the coil. The theoretical efficiency is therefore less than 50 %.
2. Superconducting furnaceContrary to an induction furnace, asuperconducting inductance furnace has adifferent approach. A constant magnetic field isgenerated instead of an AC-generated field using
coils. Adoption of a permanent magnet with aconstant magnetic field is suitable, but even lower
power consumptions can be realized using
electromagnets. A metal block can be forcefully
rotated in this constant magnetic field. Eddy
current flow leads to heating when the conductor
moves in a magnetic field. This is also describedas rotational induction heating (Figure 1).
May, 2015

Magnetic Field
Forced Rotation
Eddy Current

Fig. 1 Rotational induction heating© ISTEC 2015 All rights reserved.

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613

If the heated metal block has magnetic properties, the block is then attracted by the magnetic field (this is
not shown in Figure 1) either top or bottom of the magnetic poles. This method has been known for sometime. In the case of non-magnetic aluminum, the system efficiency deteriorates due to the higher powers
consumed to form the magnetic field in a large space. This has prolonged the realization of a system forpractical use.
Now, superconductor technology can address this issue. Superconductor technology, which is well known
in MRI applications, can generate strong magnetic fields in large spaces with little power consumption. A
factory furnace requires robust heating properties since the furnace is installed close to the metal blockrotating at 500 revolution/minute. A superconducting furnace for practical use, utilizing high temperature
superconducting technology was realized for the first time. Figure 2 shows the superconducting furnace inoperation. The power consumption was halved compared to conventional induction heating, and wastherefore highly anticipated for further market diffusion because of its advantageous energy saving
attributes. Several unit systems are currently in operation mainly in Europe, however, it is unfortunate thatthe systems are not more widespread than this. One of the possible reasons behind this could be due to adecrease in aluminum extrusion demand. In Japan, peak demand was around 2000, but is now decreasing
gradually (Figure 3). The situation now with surplus facilities, has put off new system installation, eventhough employing a superconducting furnace can attain lower running costs. However, China is significantly
increasing their aluminum demand, but they currently struggle since the high initial facility investments are
not in their favor.

Fig. 2 Superconducting furnace in operation. Unaware of the underlying high-tech superconductivity.

May, 2015© ISTEC 2015 All rights reserved.

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May 2015

Date of Issue: May 15, 2015

Superconductivity Web21
Published by International Superconductivity Technology Center
KSP, Kawasaki, Kanagawa 213-0012 Japan Tel:+81-44-850-1612, Fax:+81-44-850-1613(Unit : ton)

Shipping volume trends of aluminum fabricated products (plate/extrusion)■ Extrusion■ Plate(Year)

Fig. 3 Shipping volume trends of aluminum fabricated products (plate/extrusion).
From Japan Aluminum Association HP

3. Wind Heat Power Applications
The current proposal is to apply this superconducting furnace technology to renewable energy applications.
This is called Wind powered Thermal Energy System (WTES. Renamed from WHP), and aims for utilizing
a cheap heat storage system in order to safeguard a stable supply of power. However, heat to electric
conversion rates are currently low at around 40 %, which compares to around 70 % for conventional battery
storage. However, from the viewpoint of cheaper construction costs, power generation costs can be halved
compared to power plants utilizing battery storage. Here, employment of a superconducting furnace canrealize operations at such high temperatures where magnetism does not exist. An efficiency of 60 % isforeseeable for gas turbines that are driven at over 1000 °C. Economic projections become important as
facility costs increase. Although not essential for this article, gas turbines can be classified into either internaland external combustion types. A supercritical CO2 gas turbine is now under development, aiming for 50 %efficiency at 700 °C and having a 10 MW power output.

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