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ITER NEWSLINE 137
Until today, the ITER website only spoke the language of Shakespeare, which is the official language of the ITER Organization. Starting today, it will also speak la langue de Molière, which is that of our Host country.
The "French web" is a mirror image of the original ITER website that went online in May 2009. Its dozens of pages, totalling 32,000 words, have all been translated and adapted to the peculiarities of the French language. We hope that in that lengthy and painstaking process, we have omitted no accent—be it grave, aigu or circonflexe.
The ITER website in French will provide the world community of francophones (some 200 million people in 70 countries) with a gateway to the ITER Project. Like its English counterpart, the "French web" will be updated on a regular basis with news, stories and press clippings. It will be of particular value to our neighbours in Aix, Manosque and the surrounding towns and villages.
Starting with A like aimant, which sounds like the gerund of the verb "to love" but means "magnet"; continuing with B like bobine, which can be used to describe either a funny face or a spool of thread, but is also French for "coil," come and discover our new ITER website in French—notre site web en français.
At the mention of "pure water," visions of sparkling mountain springs tend to appear before our mind's eye. But even in its purest natural state, water is far from being pure in a chemical sense—that is, far from containing atoms of hydrogen and oxygen only. An excellent solvent, water almost always contains dissolved minerals, salts and metals, as well as sediments and other impurities.
In ITER, where 20,000 cubic metres of water from the nearby Canal de Provence will be held in the cooling tower basins, and more than 3,000 cubic metres of purified water within ITER's cooling water systems, these extra constituents all add up to one thing—trouble.
"Dissolved salts, minerals or metals in water—what we call ionic impurities—significantly increase the electrical conductivity of water," explains Babulal Gopalapillai, Cooling Water Chemistry Engineer. "Whereas on the contrary, along with its cooling function, water should serve as an electrical insulator in our cooling loops for safety reasons—especially in the cooling loops that service high-voltage electrical systems at ITER."
Impurities can also corrode steel cooling water pipes. "Not only does corrosion translate into downtime and increased maintenance costs," says Babulal, "but the combination of corrosion products in the cooling stream and neutron radiation from the plasma results in the formation of radioactive isotopes." These "activated corrosion products" need to be kept to acceptably low levels in ITER. That's where water treatment at ITER will enter the equation.
Of the 15 cooling loops planned to remove the heat of the ITER installation, more than half are dedicated to cooling the most demanding "clients": the plasma-facing components and the systems that require the purest de-ionized, low-conductivity water. These circuits make up the ITER primary cooling loops, where heat is transferred from its primary source.
Secondary cooling loops, which receive the heat from the primary loops and other sources, have slightly lower requirements in purity. Tertiary loops circulate untreated or "raw" water to cooling towers, from which heat from the secondary loops is ultimately transferred to the environment.
"By segregating the loops according to client requirements, we are able to ensure the purity and safety in the primary loops, avoiding the inadvertent release of radioactive effluents into the environment, while using lower-cost methods elsewhere," explains Babulal.
Purity in the primary loops is ensured by on-line water treatment systems, such as the chemical and volume control systems (CVCS). In a continuous manner, two to five percent of primary loop cooling water circulates through CVCS ion exchange columns and filter units that absorb ionic impurities and filter particles, and keep conductivity and activated corrosion products low.
The CVCS also controls water chemistry, providing regular measurements of conductivity levels, pH and dissolved gases. Chemists at ITER will have a wide array of tools to adjust and control chemical parameters. Are the oxygen molecules dissociating under the influence of radiation? Add hydrogen. Is too much dissolved oxygen in the cooling stream creating oxidation? Add hydrazine.
The secondary loops will also have on-line measurement of pH and conductivity levels. To keep the general level of ionic impurities low, small quantities of water from these loops will be drained when their quality level deteriorates beyond preset limits, and de-ionized water fed back into the loop—a process that Babulal refers to as "feed and bleed."
Grab sampling will be used in all loops to cross check the accuracy of online monitoring systems and to test for impurities such as calcium, zinc, sodium, silica, copper, iron, chloride, carbonates, sulphates and phosphates that could contribute to greater corrosivity or conductivity in the water supply. In primary and secondary loops, which are closed systems, water levels will be monitored continuously and any loss due to leakages made up using de-ionized water.
In the open tertiary loops, water levels in the cooling tower basins will be maintained by a continuous supply of makeup water from the Canal de Provence. This makeup flow is needed to compensate for evaporation losses and the regular discharge of water used to control the deterioration in water quality caused by evaporation. Anti-scalant will be added to combat the raw water hardness, and a biocide (ozone) used to prevent the growth of dangerous bacteria.
"The control of water chemistry has been demonstrated to have a significant influence on materials performance," emphasizes Babulal. "During ITER operation, we'll have a chemical laboratory on site, and a chemist on duty during every operating shift." Work is currently ongoing to define the exact chemical specifications required to meet client requirements, and to establish the design of the treatment systems and the sizing of purification systems. "The challenges of ITER lie in the volume of water to be managed in the cooling water systems, and in the diversity of the clients' needs," says Babulal.
And one last thing ...
ITER chemists will have the responsibility of ensuring that water discharged from the ITER cooling water systems meets the strictest environmental standards before release into the cooling water discharge basins and, ultimately, the Durance River. Temperature, pH and chemical parameters will come under close scrutiny in the ITER laboratory and again at the CEA, which is responsible for the water's final release.
The last step in the process doesn't have much to do with chemistry or laboratories, however. Regulations stipulate that local species of fish be introduced into the cooling water basins and observed for six hours. "In the end, after all of our sophisticated means," observes Babulal, "Mother Nature will have the final word!"
One key aspect of the research program of ITER is the diagnosis of the plasma and the first wall, e.g., the plasma temperature, its density, its radiative properties, its first-wall resilience. For this purpose, a large number of diagnostics peer into the ITER vacuum vessel from many different vantage points.
The focus of the design review being held next week here in Cadarache is the generic location known as the upper port plugs. The diagnostic generic upper port plug (GUPP) design is meant to be common to all upper port-based diagnostic systems. It provides a common platform, or support/container, for a variety of diagnostics. In addition, the port plug structure must contribute to the nuclear shielding, or plugging, of the port and further contain circulated water to allow cooling during operation and heating during bakeout. The port plug must withstand disruption forces, thermal stresses and seismic events.
The design of the GUPP represents the culmination of two years of collaborative work involving the ITER Organization, most of the Domestic Agencies—including a leading role by the US-DA (Princeton Plasma Physics Lab)—and several industrial contractors.
This week it was time to say goodbye to three honorable ITER staff members. After 22 years of service to ITER, covering the various phases of the project, Vladimir Mukhovatov retired—only to be picking up a new job at the Kurchatov Institute in Moscow where he started his career in 1958 on the first tokamak ever built, the T-1. "We owe you our deepest respect," said Valery Chuyanov, the Deputy Director-General of ITER's Fusion Science and Technology Department during a little ceremony. "Not only for your modesty, but also for your devotion to the project. You taught us what we know today and you also taught us what we don't know. You are an encyclopedia on two legs."
The second farewell party this week was devoted to Yuri Balasanov, "one of the pioneers of the ITER Project," said Director-General Kaname Ikeda, expressing his respect. Nominated Head of the Division of International Organizations by the Russian Ministry for Atomic Energy, Yuri took part in the early ITER negotiations. Ever since he joined the ITER Project full time in 1994 he has been in charge of staff recruitments and secondments, and he is probably "the person best known to the fusion community around the world," Ikeda said. Having moved all over the world for the ITER Project—from Moscow, to San Diego, and on to Garching and Cadarache—Yuri and his wife are finally heading back home.
And, last but not least, ITER said farewell to the Head of the Communication, Neil Calder, who is returning to the United States. In his two-and-a-half years at ITER, Neil built up the Communication team and created the tools that have shaped ITER's public identity—the ITER logo and branding, the ITER website, and the dynamic Facebook page and Youtube channel. Convinced that the potential of fusion doesn't yet occupy the place it deserves on the energy scene, he has worked to federate fusion communicators throughout the world, both within ITER and without. Neil created the spirit of ITER Communication—fun, fast-paced, transparent and informative.