Thorium Fuel Cycle Development in India

Homi Jehangir Bhabha, an Indian physicist, who had, during a pre-World War II stay in Europe, made important discoveries about cosmic rays. Upon his returned to India at the start of the war, he began to campaign for Indian research institutions deveoted to physics and nuclear energy. He quickly established himself as a scientist politician who had the ear of Pandit Nerhu, the first Indian Prime Minister. Shortly after Indian independence in 1948, Bhabha was assigned the task of establishing the Indian Atomic Energy Commission, and developing a nuclear research program.

During the first UN Conference on the Peaceful Uses of Atomic Energy (1955), Bhabha, who was the Conference President, presented a paper on Indian Atomic development. He argued that India lacked energy resources, and in order for the Indian people to have a Western standard of living, Indian electricity must be generated by nuclear means. He noted, "the necessity of obtaining enriched or pure nuclear fuel (plutonium- or uranium-233) for use in future atomic power stations of a more advanced design required the setting up during the next decade of a few atomic power stations designed to produce these materials as well as electric power.”

Bhabha once remarked that "No energy is costlier than no energy". He was what Texans use to call a wheeler-dealer. He used his position at the The First Conference to obtain British, Canadian and American assistance for the Indian nuclear program. Soon Indian Scientists were showing up at Chalk River, Harwell, and Oak Ridge for on the job training.

In addition to training, during the 1950’s, with American support and Canadian help, India began to construct its first reactor, the heavy water Cirus. What the Americans and Canadians did not notice was that the Cirus was capable of producing weapons grade plutonium.

In early 1957, Bhabha summarized his plan for the Indian nuclear energy future,

“It is likely that in the future more advanced and efficient types of atomic power stations will use concentrated atomic fuel, such as uranium-235, uranium-233, or plutonium, rather than the naturally occurring uranium. If we are not to depend on the import of such fuel from abroad, and not to build a gaseous diffusion plant involving an enormous expenditure and technical effort, it is necessary for us to start producing this fuel now by converting natural uranium into plutonium, and thorium into uranium-233 in atomic reactors. If we are therefore, not to lose further ground in the modern world, it is necessary for us to set up some atomic power stations within the coming five years, which will produce plutonium for our future power reactors, in addition to producing electricity now."

Bhabha believed that nuclear generated electricity would play an important future role in the Indian economy, and that India possessed only limited Uranium resources. However, India possessed large thorium reserves. Thus Bhabha believed that the Indian nuclear research must be directed toward the development of the thorium fuel cycle. During the 1950’s Bhabha set out a three stage development program for Indian Nuclear technology.

In the first stage, Heavy water reactors using unenriched uranium derived from India’s limited uranium reserve, would be constructed and begin operating. The use of heavy water reactors meant that India did not need to to develop expensive and power demanding uranium enrichment facilities.

During the second stage, India was to construct Fast Breeder Reactors, which burned plutonium reprocessed from the spent fuel of the heavy water reactors as well as their depleted uranium. India needed to develop breeder technology quickly, because it had limited uranium resources. Breeders allowed India’s uranium supply to be used much more efficiently.

During the third stage thorium was to be bred, and U-233 would fuel Indian power reactors.

This plan enabled India to boot strap its limited nuclear resources, into a viable nuclear energy program. Of course, along the way, something which Pandit Nehru swore on a stack of Bhagavad Gitas would never happen, did.  India used some of Bhabha plutonium to build nuclear weapons. But remarkably fifty years later, India is still following Bhabha’s three stage plan for nuclear power development. The plan is now at the beginning of the third stage.

India has 13 heavy water reactors with 4 more under construction. These Indian reactors are smaller than western commercial power reactors. India also has fuel reprocessing facilities, and a developmental breeder reactor. A full scale fast breeder (500,000 MW), which will breed both U-238 and Th-232 in a hybrid fuel cycle, is under construction, and is expected to be completed in 2010. A second large thorium fast breeder, the ATGB is already in the planning stage. The KAMINI test reactor is used to test the use of U-233 produced by the Kalpakkam experimental breeder. A Generation 3+ Thorium fuel cycle Advanced Heavy Water Reactor is also in the planning stage. India plans, by 2020, to have reactors capable of generating 20 GWs of power, most of it using thorium fuel cycle nuclear fuel. Bu 2050, India plans to produce 30% of its electricity from thorium fuel cycle nuclear generating facilities.  The Indians believe that their thorium reserve will last them for at least 350 years.

The Indian nuclear program is remarkable in several respects.  First, is the depth of Homi Bhabha's understanding of Indian nuclear resources and the sort of nuclear program that would achieve the maximum benefit from his country. The second, was the reliance on the relatively simple CANDU technology, during the first development stage and its continued development through all three stages. Reactors were kept small, 220 MW's, limiting capitol commitment for each reactor. In addition reactor design was given a chance to develop, successive improvements were made as new reactors were designed. Operational experience gave feedback to reactor designers. During the second stage, the full plutonium - thorium - U233 fuel cycle was tested in two small reactors. 

Finally, believing that they had mastered all of the individual components of their thorium fuel cycle program, the Indians have set about to build prototypes of commercial reactors that are intended to go into serial production. They have been faithful to Bhabha's vision. They have found a way to highly efficient technology, a technology that is far more efficient in its use of nuclear fuel, than the French/American nuclear system by ingeniously mastering and organizing relatively old nuclear technologies, and leveraging them into a fuel efficient system. By doing so they will achieve EROIE's many times that achieved by Western fuel/reactor systems.  They plan to supply electricity to a huge population for at least 350 years from only 500,000 t0ns of nuclear fuel.  Indian scientists and engineers are on the brink of a significant human accomplishment, the realization of Bhabha vision of bringing nuclear generated electricity to India's vast population.

Early reactor conceptual developments

Eugene Wigner (left), Enrico Fermi (right)

Some of the best scientist of the 20th century hung around around the "Metallurgical Laboratory" of the University of Chicago. The "Metallurgical Lab" was a cover for the nuclear research establishment which Author H. Compton set up at the University of Chicago during World War II. The Metallurgical Lab was to later give birth to Argonne National Laboratory. The Lab was dominated by two extremely brilliant men, who both made undoubtably made tremendous contributions to establishing the nuclear age. They were the Italian Enrico Fermi, already the holder of a Nobel Prize in Physics, and Eugene Wigner, a Hungarian engineer/physicist who was later to receive a Nobel Prize.

Although no one speaks of a rivalry between the two men, scientist associated with Metallurgical Lab began to form networks around them. After the war Fermi was to lead Argonne National Laboratory, while Wigner took a brief stint as director of the naissant Oak Ridge National Laboratory. It was a young Wigner associate from the Metallurgical Laboratory, Alvin Weinberg, who was to Lead ORNL during its years of glory.

During the war, the atomic energy research establishment quickly expanded.  J. Robert Oppenheimer, of the University of California, organized the Los Alamos team. Fermi was clearly a player in the Los Alamos project.  Wigner focused on reactor development in Oak Ridge and Hanford.   Thus the division of labor between Fermi and Wigner thus made Fermi responsible for the bomb, and Wigner responsible for the reactors.

Weinberg was drawn to Wigner, an became his assistant at the Metallurgical Lab. Both had minds that were not compartmentalized in one discipline.  Wigner was educated as an chemical engineer, and had made significant contributions to theoretical chemistry, but although Wigner never formally studied physics, his is a great name in the history of the discipline.   Weinberg's PhD crossed the lines between physics, math, and biology, and for a brief time before he got caught up in the Manhattan Project, he appeared headed for a career in biology.   Weinberg, who had studied cell devision from the viewpoint of physics and math, was well equipped to understand nuclear fission and the chain reaction. For 35 years, Weinberg stood on the stage of history, and because he was an observant and thoughtful man, he left us an invaluable record of that history. 

It is a mark of Wigner's genius that between 1942 and 1945 Wigner headed both the theoretical-physics research and reactor-engineering and development at the Metallurgical Laboratory. Wienberg was a close Wigner associate. As a reactor developer, Wigner thought like an engineer. Both the original Stagg Field reactor and the ORNL pile reactor were air cooled. It was suggested that the larger Hanford reactors be cooled with helium. He objected to the use of helium as a reactor coolant, because the then existing reactor building materials would not tolerate the high heat found in helium cooled reactors. Wigner decided that the Hanford reactors should be water cooled. Weinberg observed, "making that proposal was a very brave thing for him to do because, at that early time, it had not yet been experimentally demonstrated that any chain reaction was possible. But Wigner had so much confidence in the accuracy of his calculations (backed, of course, by Fermi's experiments) that he insisted that, though the presence of water in the reactor would reduce the multiplication factor by perhaps 3%, enough reactivity would be left to make a reactor of modest size. Moreover, Wigner emphasized that a water-cooled machine could be built much more quickly than a helium-cooled reactor."

A.H. Compton backed Wigner's plan to build the Hanford reactors with water rather than helium cooling. And the Hanford reactors were designed and built as large, water cooled, graphite moderated piles.

The British, despite their participation in the World War II Chalk River project, which developed heavy water reactor technology, were to follow the path which Wigner rejected. Their first reactors were air cooled graphite piles. They were to pay dearly for this technological regression. The infamous Windscale fire, one of the three great reactor accidents in reactor history, was a result of the British use of this primitive technology. The British air and Helium cooled, graphite moderated Magnox reactors, have proven far less durable than American Water cooled reactors, and far more expensive to decommission.

After The Hanford reactor design project was complete. Weinberg states, "there wasn't much left for Wigner's group to contribute to the project, . . ."   In another account of the the period, Weinberg reports, 

We organized a New Piles Committee which met weekly for three months during the spring of 1944. Here the senior luminaries, such as Fermi, Wigner, Szilard, and Franck, together with a few younger assistants like myself, discussed various ideas for reactors: for power, for submarines, for production of plutonium, even for inducing endothermic chemical reactions. Our imaginations ranged widely as we considered various moderators, coolants, and configurations. Inventing a new reactor was an everyday occurrence, simply because no one else had thought about these matters. At that time we were under the impression that uranium would always be scarce.

What happened next was one of the most amazing episodes in the history of science. "Wigner obtained 37 engineering patents on various kinds of reactors: reactors moderated with heavy water, homogeneous reactors, fast reactors, air-cooled research reactors, and water-cooled compact reactors enriched with uranium-235. In all those instances, Wigner served as the spark behind the designs."

Weinberg, of coursed patented the the pressurized water reactor, the basis of naval and civilian power reactors. Farrington Daniels, a chemist in Wigner's reactors group, patented the pebble bed reactor in 1945. Among the reactors that Wigner patented, along with Harry Soodak was the liquid metal fast breeder reactor. Developing the homogeneous reactor became a Fermi project at Los Alamos.

Wigner advocated a homogeneous thorium breeder reactor over his own invention, the Liquid Metal Fast Breeder Reactor. Fermi preferred the fast breeder. The advantage of the homogeneous reactor concept was that it allowed continuous processing of nuclear fuel, and the extraction of fission products, in an environment in which nuclear breeding is possible. Wigner's background in chemical engineering played a critical role in his preference. A liquid core reactor would solve many of the chemical processing problems associated with nuclear breeding. Thorium held numerous advantages over uranium in nuclear breeding. The possibility of a shortage of Uranium was one of the Metallurgical Lab concerns, and breeders were the agreed on solution to that problem. Of course uranium turned out to be anything but in short supply.

The New Piles Committee was anything but short sighted. During a April 26, 1944 meeting, Fermi outlined the plans for a Pu-239 fast breeder that would supply fissionable fuel for other reactors, he noted, "There may be nontechnical objections to this arrangement, for example, the shipment of Pu-239 to smaller consuming plants offers the serious hazard of its falling into the wrong hands."

Weinberg also states that Fermi warned in a New Pile Committee meeting that "for the first time mankind would be confronted with enormous amounts of radioactivity; we must not assume that this will be accepted easily by society."

The devision between Fermi and Wigner about breeding technologies had long term institutional consequences. Fermi's Argonne National Lab developed and championed the LMFBR concept, while Wigner's lab, ORNL, under the leadership of his former assistant, Alvin Weinberg, experimented with homogeneous reactors until the late 1950's before abandoning the technology for the Molten Salt Reactor concept.

The idea for the Molten Salt Reactor originated with V.P. Calkins, Kermit Anderson, and Ed Bettis in about 1947. By 1950, Alvin Weinberg, Warren Grimes, R.C. Briant, and my father, C.J. Barton, Sr. were supporting the project. Although technologically more challenging, the use of liquid salt fuel solved many of the problems associated with homogeneous reactor. The MSR/LFTR concept thus is very much a part of the intellectual heritage of Eugene Wigner, even though he did not invent it.

Morning thoughts, Leukemia and German Reactors

Lee Progress

On Thursday, Duke Energy submitted a licensing application for the Lee Nuclear Station in Cherokee County, North Carolina. This must have been a moment of great satisfaction to Ruth of We Support Lee, Nuclear Australia has already extended its congratulations and I join them in the sentiment.

Leukemia and reactors

There is a considerable gap between the the known causes of leukemia and the causes of cancer clusters in a given population. A recent German report found that between 1980 and 2003, 37 children living in the vicinity of 16 reactors contracted leukemia. The report states that for the subject population, 17 cases would have been expected. More information would have been helpful. For example, news releases do not mention patterns associated with individual reactors. It is very unlikely that the cases were distributed between all reactors evenly, or that they were distributed evenly through time. I say this because it is known that a leukemia cluster occurred in the North German community of Elbmarsch between 1990 and 1996. All nine of the children involved lived within 4500 meters of the Kruemmel reactor. Five of the nine cases were reported within 18 months of each other in 1990-1991.

The other 4 were reported in 1995-1996. The first six cases could be further localized to about 20% of a 5 Km ratdius from the plant. Five more cases were reported in the same area between 1999 and 2005. The same report stated that there were several other leukemia clusters associated with reactors in Europe. However, a comparative study of the area around the Savannah River Reactor operation, and the Kruemmel revealed that childhood leukemia case levels were not elevated in the Savannah River area. Since several releases of radioactive tritium were known to have occurred from the Savannah River site, and those releases exceed those from the Kruemmel site by several orders of magnitude, it is unlikely that releases of tritium played a role in the Kruemmel cluster.

Radiation monitoring in at the Kruemmel reactor and in the surrounding area have not detected releases of radioactive material from the reactor. However, reports (for example, here) indicate the presence of 238Pu, 239,240Pu, 241Am, and 244Cm in homes in the Elbmarsch community.

There have been reported leaks of coolant water from the Kruemmel facility, but this could hardly explain the presence of transuranium elements in Elbmarsch homes. No transport vector between the Kruemmel reactor has been found, or as far as I can tell, even suggested. The transuranium element could have come from fall out from nuclear tests, or Chernobyl fallout. But this is deemed unlikely. The Elbmarsch leukemia cluster has been the subject of extensive and ongoing study. The Kruemmel facility has also been the subject of intensive study and on going monitoring. To date no source of environmental transport of reactor byproducts inside the reactor or from within the facility has been found.

Studies of an association between childhood leukemia and the proximity of reactors have been inconclusive. One 1991 study of 107 counties near 62 nuclear facilities by the American National Cancer Institute found that the childhood leukemia rate for the reported areas dropped slightly after the reactors started operating. Another report of the same study indicated that one childhood Leukemia cluster was associated with the Millstone Power Plant located in New London, Connecticut. Three of the studied facilities had significantly fewer leukemia cases than were expected. Windham County, Vermont, where the Vermont Yankee reactor is located was reported to have only 9% of expected childhood leukemia cases.

Repeated studies failed to uncover an association between The Three Mile Island accident and childhood leukemia (see here , and here. Even more remarkable, studies have failed to uncover a relationship between exposure to radiation from Chernobyl and childhood leukemia (see here, and here). In the latter study, "Childhood leukaemia in Belarus, Russia, and Ukraine following the Chernobyl power station accident: results from an international collaborative population-based case–control study," S.Davis, RW Day, KJ Kopecky, MC Mahoney, PL McCarthy, AM Michalek, KB Moysich, LE Onstad, VF Stepanenko, PG Voillequé and others, "conclude that this study provides no convincing evidence of an increased risk of childhood leukaemia as a result of exposure to Chernobyl radiation, . ." They report some evidence that suggest effects of exposure to very low levels of radiation, as a causivetive factor in leukemia, but acknowledge that "prolonged exposure to very low radiation doses may increase leukaemia risk as much as or even more than acute exposure, but are inconsistent with published literature regarding the risk of leukaemia in relation to protracted radiation doses of the very low magnitude observed in this study."

It is clear then that radiation and isotope dangers from large scale and well known incidents like Three Mile Island and Chernobyl are not correlated with increased incidents of leukemia among exposed children. To date, leukemia clusters are far more likely to be associated with the operation of European than American reactors. They do not appear to be associated with large scale radiation releases. If they are caused by low level radiation increases in the environment, it should be expected that leukemia clusters should be associated with locations know to be at higher risk for radiation exposures. One such risk would be found in mountains, but altitude seems to play less a role in mountain related cancer clusters than the presence of tungsten.

It is clear then that there have been leukemia clusters associated with a few nuclear reactors. Some have been explained and others have not. Most reactors appear to be safe. Despite extensive German investigations the Elbmarsch cluster is still unexplained. If a defect in the design or operation of the Kruemmel reactor was responsible for the leukemia cluster, it would be very useful to know. Thus the Elbmarsch leukemia cluster has not been explained and leaves us with a mystery.