indian students Radio Tagged in U.S.

Indian students radio -tagged in U.S.

More than  a dozen Indian students from among  hundred who have been  scammed by dodgy university in California have been ‘Radio  Tagged “ with tracking devices in an action New Delhi described as unwarranted and asked to be removed even  an angry community activists said it is a violation of their rights and dignity.

Authorities from immigration and customs enforcement( ICE)who interrogated scores of Indian students evidently conned by Sham Tri -Valley university in Pleasanton, California  university shacked ankles of several victim’s with Radio Tracking devices. The students said officials told them that devices fitted with GPS technology were meant to monitor their movement while their cases were being examined.

Scores of students mostly from Andhra Pradesh were caught up in a scam  in which dubious university allegedly helped foreign nationals illegally acquire immigration status. Investigation by U.S. authorities found  that while students were admitted to residential and online courses of university and on paper lived in California ,in reality they worked illegally in various parts of country.

The students say they were  unaware of dodgy nature of university and they were conned. In a petition to the secretary of homeland security and director ICE the effected students said they signed up believing it was a bona fide and legitimate university that had been registered with studies exchange visitor information system (SEVIS ) database.

In deed Tri-Valley  university is among the SEVIS approved schools listed on the U.S. ICE website. But U.S. officials say some of the students obtained visas fraudulently and other are on violation of their visa and immigration status. ‘ such students have been placed under ISAP ( intensive supervision and appearance program by ICE and put in removal proceedings necessitating Radio -Tagging “ they said.


Hundreds of Indian students who have gotten scammed by a dodgy California based had it coming. Tri -Valley university ( TVU) had reputation as a “ diploma mill “ that offered a spurious route to job and immigration in the U.S.inquiring  students and professionals knew about it , discussed it in immigration forum  and warned others about it. But eager believers looking for  a short cut to immigrating to U.S. through questionable academic route ignored the red flag’s. after U.S. authorities busted the scam and estimated 1500 students, some of them gullible victims, some of them scheming immigrant hopefuls, face financial loss of time, loss of credits, loss of face, and even some case  face deportation.

Here the how the scam unfolded . India from among all countries has been sending the maximum  number of students to U.S. colleges over the past decade -some 10,000 to 15,000 try to get into the top 50 schools, which have stringent  qualification standards, including exams such as GRE and GMAT,beside TOEFL an English  proficiency test. The process involves giving admission on the basis to test scores, in view  of  which the university sends 1-20 documents to accepted students , which he or she present to embassy or consulate in home country to get F-1 student visa.

But recent years several dodgy varsities have come up which waive GRE/ GMAT requirements as long student can pay dollars up front in the form fees . More permanently there colleges dubiously facilitate optical curricular practical training (OPT) and curricular practical training (CPT) two routes to employment and at the end of college degree from the first day of enrollment.

Typically in recognized, well -regarded universities all students must be enrolled as full time studies for a year before receiving CPT/ CPT. For hundreds of thousands of Indian students who are eventually become U.S. citizens, OPT and CPT are the first steps to employment-based visa (usually HI-B) ,green card and citizenship in that order.

The Tri-Valley university and similar schools had a “well earned reputation of shortening the process by offering OPT / CPT from day one which meant ‘students could get on employment track, even they began “college” . In fact  TVU did not even have a campus in traditional use. It had solitary ,sorry looking building, bought in 2010  which housed every thing from distraction offices to class room, from which random lectures were transmitted over internet to students across the U.S.

It took January this year for U.S. authorities to cotton on the scam or look at charitably to spare the man power for a nation wide crackdown . Although TVU has based on Pleasanton, California its students scattered thought country from east coast to middle to west to deep south . Many of them illegally employed. Although it was allowed only 30 students admission pending a rendition , TVU  managed to work the system to admit 1500 students. Apparently there were companies across U.S. which used TVU F-1  visa based  CPT/ OPT to beat the H1-B visa requirements which regulate delay, insist on not replacing  American  workers.

On January 19, after raiding TVU  getting student record from school and shut it down, immigration  officials began knocking on the doors of TVU students across country or leaving NT As (notice to appear ) asking them to get in touch with local office . In some cases, officials merely made preliminary inquiries, in other students were interrogated for up to three hours. Some had their passport taken away if they decline to deposit voluntarily. And in rare cases where officials found egregious violation  visa terms on questionable visas, students were shacked with electronic monitoring devices till further  inquires.

Worried parents in Hyderabad who called up the helpline 23220603 on Sunday left frustrated a lot . The CMO opened the helpline  to provide information to parents and relatives of students stuck in U.S. but on Sunday no body answered the calls.

A major chunk of the scammed students are from A.P. , Tana  and human rights group urged chief minister Kirankumar  Reddi to speak directly to U.S. Consulate in city. Ironically several parents discovered too late that their wards had taken admission in Sham university.

‘ We were under impression that our boy was another university in California . We did not know that he had taken admission in Tri -Valley two month back . We are worried now .” a parent said.

Students are now left two options. Either a pay bond of 1500 dollars to immigration magistrate to get rid of the tracking tags and return to India or get immigration papers settled and opt for another university a relative of student informed.

Condemning the radio -tagging of Indian students in California  Tri-Valley university as in human and unacceptable. India’s minister for external affairs  Mr. S.M. Krishna on Sunday demanding action against official responsible for it.

“ the Indian students are not criminals . The radio-callers should be removed, and U.S. government should take action against official responsible for in human act .” Krishna told to reporters.

Addressing reporters  Krishna further said “ A number of scholars have got transfers from some universities and there are number of students who got necessary Visa from U.S. Consulate in India. The sudden closure need to be looked into by federal government  . “

Krishna told the parents of students not  to worry saying that government had taken up the issue with washing ton.

Overseas India’s affairs minister Vayalar Ravi on Sunday said he has asked India mission in Washington to see whether any agent in Andhra Pradesh was involved in this incident.

Do I have to own a website to use AdSense?

Do I have to own a website to use Ad-sense?

Toshiba -ABWR -light water reactors

Toshiba -ABWR -light water reactors

ABWR  enjoys a reputation for excellence in respect to safety economy, operalability and reliability. The first ABWR Kashiwazaki - Kariwa unit no.6 commercial operation in 1996,followed by unit no.7 the following year, both delivered  to Tokyo Electric Power Company since these both units have shown  stable performance.

Successively ,Toshiba took  change of nuclear reactor equipment  of Hamaoka unit no.5 of Cheibu Electric Power Co in as their third ABWR, incorporating the latest technology. Hamaoka unit no.5 commercial operation in January 2005 and emerging as a plant with electricity out put of 1380 MW one of world’s largest in out put.

Various new technologies were employed in Hamaoka unit no.5 to improve reliability and economy such as “S-FMCRD (Seal-less-Fine motion of control rod ) “ which eliminated the use of seal housing by adopting a magnetic coupling A-PODIA ( Advanced plant operation by displayed information and automation to improve repeatability with large display panel,ASD-the multiple drive power supply to reactor internal pumps’ that can drive two or three Tips with large capacity inverters.

Toshiba is currently deploying ABWRs for international market, which features are improved design and are backed by Toshiba’s  experience obtained through construction, inspection and maintenance of these domestic power plants.

Dreams come true with Toshiba’s excellent experience and high technology on nuclear power generation, it is advanced boiling water reactor (ABWR)its short construction   period  and large capacity take power generation a long step forward  in 21st century Kashiwazaki- Kariwa unit no.6 1356 Mwe  has been in commercial operation operated by TEPCO ( Tokyo Electric Power Corporation. It is world’s first ABWR.

Toshiba was representative administrator for this huge unit no.6  construction project and also 2nd ABWR Kashiwazaki -Kariwa unit no.7 same capacity as unit no.6 has been in commercial operation since July 2  1997.

ABWR -THE ADVANCED BOILING WATER REACTOR

Boiling water reactor (BWR)  provide one of the today’s  most widely used  means of nuclear power generation. In BWR plant , reactor uses low enriched  uranium as a fuel for bringing moderator and coolant water  to boil directly at the reactor core. The result steam drives turbine. Toshiba advanced boiling water reactor the culmination of years of experience in BWR construction takes  and enhance the best elements of company’s BWR  technology .

Domestic and overseas development of advanced boiling water reactor

Since Toshiba delivered the world’s  first advanced boiling water reactor (ABWR)  to TEPCO  in 1996 ,Toshiba has been  devoting continuous  efforts to construction and  operational support of ABWR  systems as a major project. Toshiba now promoting domestic  and overseas ABWR systems along with standardization of ABWRs.

Toshiba also engaged in research and development of core technologies to support further promotion of ABWRs  as a concurrent to issue of global warming and energy security for individual countries.

Global deployment of AP1000 TM -third generation plus nuclear power plant

Westinghouse Electric co (WEC) is promoting expanded global deployment of AP1000 TM pressurized water reactor (PWR)which is only third generation plus nuclear power plant to have received design certificate from U.S. NUCLEAR REGULATORY COMMISSION (NRC) based on proven performance of WEC-designed PWRs, the AP1000TM not only achieve a significant reduction in the amount of required compared to with conventional PWR systems by making use of passive safety related systems but also makes it possible to reduce construction costs and shorten the construction period by means of advanced  construction technologies such as modular construction techniques, steel -plate -reinforced concrete (SC) structures and so on. In china four AP1000 TM plants two in  Sanmen  and two in Haiyang are under construction schedule. In U.S. as well the p reconstruction of two out of six contracted plants is currently underway at Vogtle  site in Georgia and V.C. summer site in   South Carolina WEC is accelerating proposal activities in response to increase in nuclear power plant construction plans in many countries thought the world.

DEVELOPMENT OF NEXT GENERATION LIGHT WATER REACTOR

The next generation light water reactor development program, a national project in Japan was inaugurated in 2008. The primary objective of this program is meet the need of replacement of existing nuclear power plants in Japan after 2030. With the aim of setting global standard design the reactor to be developed offers greatly improved safety, reliability and economic efficiency through  several innovative technologies including a reactor core system with uranium enrichment 5 to 10 percent a seismic isolation systems, long life materials, advanced water chemistry, innovative construction techniques, optimized passive and active safety systems innovative digital technologies and so on.

In first three years, a plant design concept with innovative features is to be established and effectiveness of program will be reevaluated. The major part of the program will be coupled in2015. Toshiba is actively engaged in both design studies and technology development as funding member of this program.

IMPROVEMENT OF CAPACITY FACTOR OF OPERATING POWER PLANTS

The capacity factor is key factor indicating the performance of operating nuclear power plant. To increase economic efficiency while reducing carbon dioxide emissions, a strong need exists worldwide improvement of capacity factor of nuclear power plants. The average capacity factor in Japan  is approximately 70 percent is compared to more than 90 percent in other countries. This difference is due to both shorter operating cycles and larger duration of maintain ace in Japan, despite a decline in number of outages in recent years reflecting the abundant accumulation  of experience and introduction of new technologies, in this field. To rectify this situation Toshiba has embarked on smaller nuclear power plant plan, a new project aimed at achieving a capacity factor 95 percent more and has been developing and introducing the relevant technologies.

APPROACH TO SECURING OF  STABLE NUCLEAR FUEL SUPPLIES

Toshiba aid Westinghouse electric co (WEC) a member of Toshiba group are capable of supplying both Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) plants to satisfy a broad range of customer requirements. Further more  to meet growing demand for securing of nuclear fuel supplies, Toshiba and WEC have been promoting the strengthening and further expansion of supply chains in the field of uranium production, uranium hexafluoride  (Uf2) conversion ,uranium enrichment and fuel fabrication.

ACTIVITIES RELATED TO ESTABLISHMENT OF NUCLEAR FUEL   CYCLE 

As a total nuclear power plant supplier, Toshiba has designed and constructed  many of major components  of Rokkasho  Reprocessing Plant of Japan Nuclear Fuel Limited , Japan  first commercial reprocessing plant for establishment of a nuclear fuel cycle in Japan. To reduce the load on global environment Toshiba now engaged in design and development of new facilities for the plant including waste treatment  facility and storage facility. Toshiba also promoting research  and development of advanced reprocessing technology to realize the next generation nuclear fuel cycle, in order to secure a stable energy supply in future.

DECOMMISSIONING  TECHNOLOGIES FOR  NUCLEAR POWER PLANTS
Commercial operation of number of nuclear power plants ended and decommissioning of these plants, including dismantling facilities, decontamination of radioactivity, treatment of radioactive waste, and soon has commenced .

In response to these circumstances  Toshiba has developed a various decommissioning technologies for nuclear power plants including those for decontamination, dismantling  and waste treatment as well as radiation measuring equipment utilization of core technology for design construction , maintenance and preservation cultivated  through Toshiba  experience in   nuclear power plant development. Toshiba contributing both designing of rational decommissioning plans and accomplishment of actual decommissioning through the application of these technologies.

ACTIVITIES TOWARDS REALIZATION OF NUCLEAR FUSION REACTOR


Toshiba aim of realizing nuclear fusion reactor,experimental nuclear fusion reactors are carefully under development with international co-operation.

FUNDAMENTAL TECHNOLOGIES TO SUPPORT NUCLEAR POWER PLANTS

With aim of enhancing of safety and improving the economic performance of nuclear power plants, Toshiba has been developing the following fundamental technologies to support nuclear industry.

1. An advanced core and fuel analysis technology for next generation reactors applicable to the design of innovative fuel and core which has  more complex geometry than before

2. An advanced material technology and can contribute to longer plant life through development of durable materials that are able to withstand high radiation environment and reduce radioactive waste.

3.Maintain  technology to support high performance in daily plant operation and extended operating life.

off shore wind energy and its advantages

Offshore wind energy and its advantages

Wind is air in motion. Since earth’s surface is made of various land water formations. It absorb the sun’s radiation on evenly, wind is produced by uneven heating of earth’s surface by sun.

On shore, wind energy  has been utilized for generation for more than  two thousand years. In modern times, wind energy is mainly used to generate electricity primarily through use of wind turbines. Wind flows over the airfoil -shaped blades of wind turbines, causing lift (similar to the lifting force on air plane wings) causing turbine blades to turn. The blades are connected to a driving shaft that turn the electric generator to produce electricity.

Offshore wind energy sources

Offshore wind turbines are being used in a number of countries to harness energy of moving air over oceans and convert into electricity. Off shore wind tend to flow at higher speeds than on shore winds, thus allowing turbines to produce more electricity. Much of this potential energy is near major population (and energy load) center where energy cost are high and land based wind development opportunities are limited.

Because the potential energy produced from the wind is directly proportional to the cube of wind speed increased speeds of only few miles per hour can produce significantly larger amount of electricity. For instance a turbine at site with an average wind speed of 16 mph would produce 50 per cent more electricity than at a site  with same lab-our  and average wind speeds of 14mph.

Many offshore areas have ideal wind conditions for wind facilities , Denmark and U.K. have installed large offshore wind facilities to take advantage of consistent winds, today produce more than  600 MW of offshore wind energy in installed world wide all shallow water (,<30 meters) off coasts of Europe . Proposed off shore wind projects through 2010 amount to more than 11000 MW with 500 MW each in U.S and Canada and remainder in Europe and Asia.

Commercial-scale offshore wind facilities currently are similar to the onshore wind facilities but with modifications to prevent corrosion and protect against wave and wind Interactions. Because  roughly 90 per cent of U.S. resources are over water that are much deeper than European water where commercial facilities are currently sited, new technology are being developed (e.g strengthened tower foundation) to harness the wind in harsher condition associated with deep waters.

Offshore wind facilities today are generally developed and operated as follows . Once a suitable place for wind facility is located piles are driven into seabed. For each turbine  a support structure and tower to support turbine assembly, to house the remaining plant components, and to provide sheltered access for personnel are attached to the piles. After turbine (generally three blade rotor connected through the drive train to generator ) is assembled, wind direction sensors turn the nacelle( a shell that encloses the gearbox, generator  and blade hub) to face into wind and maximize the amount of energy collected. Wind moving over the blades make them to rotate around  horizontal hub connected to a shaft inside nacelle . This shaft, via gear box powers a generator to convert the energy into electricity.

Offshore turbines have technical needs not be required of on shore turbines due to the more demanding climate environmental exposure offshore . Offshore turbines look similar to those of onshore with several design modifications. This include strengthening towers to cope with wind-wave interactions, protecting the nacelle . Components from sea air and adding brightly colored access plat form for navigation and maintain. Offshore turbines are typically equipped with corrosion protection, internal climate control ,high grade exterior paint, and built in service cranes. To minimize expensive service, offshore turbines may have automatic greasing systems to lubricate bearings and blades and preheating and cooling systems to maintain gear oil temperature within a narrow temperature range. Lighting protection system minimize the risk of damage from lighting strikes that occurs in frequently in some location offshore. There are also navigation and aerial warning lights. Turbines and towers are typically painted in light blue or grey to help them blend into sky. The lower section of support towers may be painted bright colors  (e.g. yellow to aid navigation and high light the structure  for passing the vehicles.

Off shore wind international growth

European offshore wind power grew nicely in 2010. Europe experienced record growth in offshore wind power capacity last year 2010. They installed 308 new offshore wind turbines which represents a 51 per cent increase in installed capacity over 2009. Overall nine offshore wind firms in five Europe countries came online, yielding 883 MW of new generating capacity.

The European total 1,136 off shore turbines produce a total of almost  3 Giga watts  (2964 MW) and supply enough power for about 2.9 million households. Breaking it down by country the U.K. is in lead with total off shore wind capacity 1,341 MW ,next comes Denmark (854MW),the Netherlands (249 MW),Belgium(195 MW) ,Sweden (165MW),Germany (92 MW),Finland (26 MW) ,Ireland (25 MW)and Norway (2.3 MW).

Next year total European wind power capacity is expected to further increase between 1000 and 1500 MW and while its easy to pinpoint  fingers at the U.S. offshore wind capacity which right now is virtually nil, there are a couple of projects that are getting close-cape wind Massachusetts and Block Island in Rhode Island. One thing to keep in mind is that turbines off U.S. coast line have to deal with frequent tropical storms and hurricanes. Turbines built off U.S. coast lines are going to have to be built and installed differently.

Optimizing off shore wind farm planning, design and construction

China is giving top priority  to develop off shore wind power projects to meet ambitious energy market. Its offshore wind potential is estimated at more than 750 GW compared to 253 GW of land-based wind power potential, according to china meteorological administration. In mean time government is putting out large scale offshore wind power  concession projects to tender. The national energy administration has also asked the country’s 11 coastal provinces to report plans for offshore wind farm concession projects.

These tremendous development opportunities require the industry to be effectively equipped with the right skills, technique and technology to optimize planning, design, construction and operations of wind power projects in complex and difficult offshore operational environments.

With that said ,it is of incredible value to bring experiences and lessons learn t from successful projects all around would put together  with an in depth analysis of most pressing challenges in this spinning market
energy is pleased to present offshore wind power development ASIA -2011 and bring the key shareholders together to benefit from this carefully researched and designed off shore wind energy platform.

Sucess story of nuclear power in France

Success story of nuclear power in France

Nuclear power is primary source of energy in France. 79 percent of nuclear power contribute to the  total production of electricity. France is also world’s  net exporter of electric power 18 percent of total production of electricity to Italy, the Netherlands, Belgium , Britain and Germany as its electricity cost is among lowest in Europe. France  nuclear power industry has been called “ a success story “ that has put nation ahead of world in terms of providing cheap, co2 free energy. France nuclear reactors are mainly used in load following mode and some reactors close on week ends because there is no market for the electricity. This means that the capacity factor low by world standards which is not ideal economic situation for  nuclear power plants.

As on 2002, Electricite  De France (EDF) the country main electricity generation and distribution  company manages 59 nuclear power plants. At 2008,these plants produce 90 per cent of EDFs and 78 per cent France’s electric power production, making EDF the world leader production of nuclear power percentage.

In 2006 French government asked Areva and EDF to build next generation nuclear reactor, the EPR ( European Pressurized Reactor ) at the Flamanvile  nuclear power plant. This followed in 2008 by presidential announcement of another new EPR spurred by high oil and gas prices. A site for that unit should start in 2011.

Since France first power plant was opened in 1965 in 2001 Areva the world leading company in nuclear energy was created by merger of CEA industrie  and Cogema (now Areva NC) its main share holder is French owned company CEA, but the German government holds, through Siemens , 34 per cent share Areva subsidiary Areva NP in charge of building EPR ( third generation nuclear reactor ).

Technical over view

During such a large percentage over view electrical production from nuclear power is unique in France. This reliance has resulted in certain necessary deviations from standard design and function of other nuclear power programs. For instance, in order to meet changing demand thought the day, some plants must work as a peaking power plant, whereas most nuclear power plants in world operate as base load plants and allow  other fossil and hydro units to adjust the demand. Nuclear power in France has a total capacity factor around 77 per cent which is low due to load following. However availability is around 84 per cent including excellent overall performance of plants.

The France 8 power plants in the nation were  gas cooled reactor types ( UNGC reactor ) where development was pioneered by CEA, coinciding with uranium enrichment program, EDF developed pressurized water reactor (PWR) technology which eventually became dominant type. The gas cooled reactors located at Brennilis ,Bugey, Chinon, and Marcoule all have been shut down.

All operating plants today are PWRs with exception of Phoenix , which part of an initiative to develop sodium cooled fast breeder reactor technology. The super Phenix a larger, more ambitious version has been shut down.

The PWR plants were all developed by Framatome ( which Areva now ) from initial Westinghouse design. All PWR Plants are one of variation design having out put power of 900 Mwe.1300MWe,and 1450MWe .The repeated use of these standard variants of design has afforded France the greatest degree of nuclear power plant standardization  in the world.

900MWe class
There are total 34 of these reactors in operation most are constructed in 1970 and  early 1980s. In 2002 they uniform review and all were granted a 10 year life extension.

1300MWe

There are 20 reactors of this design  ( four steam generators and four primary circulation pumps ) operating in France.

1450 Mwe(N4)class.
There are only 4 of these reactors housed at two  separate sites Civaux and Chooz . The construction of these reactors started in1984 and 1991 but full commercialized operation did not begin until 2000 and 2002 of thermal fatigue flaws in heat removed systems requiring the redesign and replacement of parts in each N4 power site. In 2003 the station were up graded to 1500MWe. It is unlikely that more of this class will rebuilt because it is expected to be superseded by large 1650MWe EPR design.

European Pressurized Rector

The next generation design for French reactor will be European Pressurized Reactor ( EPR ) which will have a broader scope than France alone with pilot plant in Finland undergoing construction and with marketing activities extending to United States and China. The first French EPR is under construction at Flam vile nuclear power plant and should be operational in 2012. The second EPR reactor will be built at Penly  nuclear power plant with construction  starting 2012 and completion schedule for 2017.

The reactor is newest reactor design in the world. It was developed by AREVA contributing its N4 reactor technology and German company SIEMENS  contributing KONVOI reactor technology. In keeping with French approach of highly standardized plants and proven technology. It uses more traditional active safety systems and is more similar to current plant design than international competitors such as AP1000 or ESBWR.

In 2005 EDF announced plan to replace current nuclear power projects with new 1630MWe units as they reached end  of life, starting around  2020. This decision confirm that France is planning indefinitely using nuclear power as its primary electric source. In order to replace the current 50 reactors one large unit will have to be built about every year for about 40 years. 

Cooling

The majority of nuclear power plants in France are located away  from seacoasts and obtain their cooling water from rivers. These plants employing cooling towers to reduce their impact on the environment. The temperature of emitted water carrying waste heat is strictly limited  by French government and this has proved to be problematic during recent heat waves.

4 plants equaling 14 reactors are located at coast.
Grave lines nuclear power plant
Penly nuclear power plant
Paluel nuclear power plant
Flamanvile nuclear power plant

These 4 gets their cooling water directly from ocean and can thus dump heat directly back into sea, which is slightly more economical.

Fuel cycles.

France is one of the few countries in world with active nuclear reprocessing program with the COGEMA la Haque  site. Enrichment work, some MOX fuel fabrication and other activities takes place at the Tricastin nuclear power centre. Enrichment is completely domestic and is powered by 2/3 of the out put of nuclear power plant Tricastine.  Reprocessing of fuel from other countries has been done for U.S. and Japan who   have expressed the desire to develop a more closed cycle similar is what France is achieved. Mox  fuel fabrication  series have also been sold to other countries notably US. for the Megatons to Megawatt program using plutonium from dismantled nuclear weapon.

While France does not mine uranium for the front end of fuel cycle domestically. French companies have various holding in uranium market. Uranium for the French program  total 10,500 tonnes  per year coming from various location sites such as

Canada -4500 tons /year
Niger ----3200 tons /year

Final disposal of high level waste is planned to be done at Mause/ Hautemame  under ground research laboratory deep geological repository.

India should develop nuclear energy with international technology to reduce dependence on oil and gas resources just like the way France developed nuclear energy in their country.

Nuclear pwer equipent plant at VIZAG

 U.S. FIRM TO SET UP NUCLEAR POWER EQUIPMENT PLANT

A U.S. based company, Brighton group, has proposed to set up  a 600 million dollars (RS 2880 crores ) nuclear power equipment manufacturing facility near the port town of Vishakhapatnam.


Major industries minister J.Geeta Reddi informed to the media on Thursday that facility, proposed to come up at Nakkapalli, would manufacture three to four nuclear reactor units per Annam at a cost of 200 million dollars each.

It would provide direct employment to 2500 highly skilled people, including 500 engineers and indirect employment to about 10,000 Geeta Reddi added.

The minister said Brighten president & CEO Kit Kung met chief minister N.Kirankumar Reddi at camp office on Thursday and sought his support for getting natural gas allocation for proposed plant. “We will sign a memorandum of understanding (Mo U) for project in the next two weeks “ she said.

The minister said the company wanted special economic zone status for their facility, which would be ready in two years in an area of 800 acres,Geeta Reddi said.

This would be major venture for  Brighton group in the country. They have a major presence in China, apart from U.S. Over one lakh people would get employment in next five years as several ancillary units are expected to come up simultaneously  the minister said.

Interacting with the media, Kit Kung said they were currently operating a similar plant in china where large nuclear reactor units were being manufactured.

“ The system in China is not favorable for western world, hence we have come to India .the Indian plant will be similar to china plant. The upcoming facility will service not only Indian nuclear power plants, but also international markets. We will make this facility our global export base “ the Kung said.

In a reply to a query on sourcing raw material, he said they use metal scrap ,mostly ship breaking units. At least 30,000 tons of steel is  needed annually for manufacturing these nuclear reactor units  , Kung said.

Kung extended an invitation the major industries minister, Industries principal secretary B.Sam Bob  and Andhra Pradesh Industrial infrastructure corporation MD B.R. Meena  to visit Briton facility in china.

Brighton Group is heavy equipment and forged steel manufacturing company that manufacturers the largest forged steel components used in third generation nuclear power plants, besides conventional power plants, ship building and petro chemicals.

Mitsubhisi - Pressurized Water Reactor

 Mitsubishi -pressurized  water reactor

In 1970 Mitsubishi constructed  first nuclear power plant in Japan using pressurized water reactor (PWR) technology. Mitsubishi has been improving PWR plants with own  operational experience as well as through extensive research and development . With vast knowledge Mitsubishi able to supply PWR plants with unparalleled level of reliability, safety and out put capacity to their customers. PWR technology is used two-third of nuclear power plants now operating in the world.

Mitsubishi are now planning next generation plants, the Tauruga 3 and 4 using Advanced PWR (APWR) technology. These scheduled for operation by Japan Atomic Power Company beginning 2015.At over 1500 MW out put, they will have highest capacity  in the world. These units will be capable of producing 30 per cent more total energy than conventional 4 loop plant. The APWR  design will also will also incorporate a high performance core that loads (MOX) fuel and operates over longer cycles.

For four decades, Mitsubishi Heavy Industries (MHI)  has been supplying reliable products and services to utilities operating nuclear power plants using pressurized water reactor technology. Mitsubishi provides basic plans and design component manufacturing, plant construction, on going maintenance, the full nuclear fuel cycle ( from uranium enrichment to final waste disposal ) and heavy investment in research and development of new technology.

The basic design of PWR plant is simple pressurized water is used as reactor coolant and reactor turbine systems are separated by steam generators in indirect cycle system.

Mitsubishi use PWR technology in their plant because Mitsubishi believe Mitsubishi design provides and enable a compact design for entire power plant. The chief benefits are reduced generation  costs and enhanced operatically and maintainability.

The special features of Mitsubishi PWR plants include

. The higher moderator density allows minimization of rod pitch by reducing the no of fuel assemblies and reactor core size

. The absence of bulk boiling in the core limits cladding corrosion thus increasing fuel reliability.

.The open -lattice fuel assembly design contributes to efficient use of neutrons, resulting in fuel economy.

 . The inherent self controlled mechanism in design use gravity to ensure a safe shut down  capability.

. Mitsubishi PWR plants  generate extremely low quality of radioactive wastes.

. The no activated turbine system can be easily operated and maintained.

. The emergency heat -removal capability of secondary system enhances reactor safety.

. The plant design adopts a system equivalent to dry -type reactor containment systems.

.The low centre of gravity plant design provides stronger seismic resistance.

U.S. - APWR design

As a result of extensive verification and qualification testing Mitsubishi developed an Advanced Pressurized water reactor (APWR) design that is more efficient with greater out put than any previous power plant. The design slightly modified to satisfy U.S. and international quality requirements as U.S.-APWR, and it will be become design that Mitsubishi sell around globe. The US-APWR satisfy Mitsubishi customer requirements with best performance for safety, economy,operation and maintenance.
The main features of the U.S.-APWR DESIGN  reactor
. Electric power    --- 1700 Mwe
. Core thermal  power ----4,451MWt

Other features of US-APWR include
Enhanced safety
. A four tram safety system for enhanced redundancy
. An advanced accumulator
. An -in containment refueling water   storage fit
Enhanced reliability
. A steam generator with high corrosion resistance.
. A neutron reflector with improved internals.
. A 90 per cent reduction plant shut down compared other four loop PWRs.

Attractive economy
. A large core with thermal efficiency  of 39 percent
. Building volume per Mwe  that is four fifths of other four loop PWRs.

More environmental friendly
. A 28 percent reduction in spent fuel assemblies per Mwh compared to other four loop PWRs.
. Reduced Occupational radiation exposure.
. Capacity to use mixed oxide (MOX) fuel made from reprocessed nuclear fuel waste.

VVER Russian reactors

VVER  Russian reactors

The Russian abbreviation VVER  stands for water cooled water moderated energy reactor. This describe the pressurized water reactor design. The earliest VVERs were  built before  1970. The VVER 44o model V230 is the most common design, delivering 440 MW of electric power. The V230 employees six primary coolant loops each with   a horizontal steam generator.

A modified version of VVER -440 model V213 was a product of first nuclear safety standards adopted by Soviet  designs. This model includes added emergency core cooling and auxiliary feed water systems as well as up graded accident localization systems. The largest VVER 1000 was developed after 1975 and is four loop system housed in a containment type structure with a spray steam suppression systems.VVER  reactor design have been elaborated to incorporate automatic control passive safety and containment system associated with western third generation nuclear reactors.

Reactor fuel rods are fully immersed in a water kept at 15 Mpa of pressure so that it does not boil at normal (220 to over 300 degree Celsius )operating temperature. Water in the reactor serves both as a coolant and moderator which is an important safety features . Should coolant circulation fail the neutron moderation effect of water diminishes reducing reaction intensity and compensatory for loss of cooling a condition known as negative void coefficient. The whole  reactor is encased in massive steel pressure shell. Fuel is enriched 2.4 per cent to 4.4.per cent of U-235or uranium dioxide (Uo2 ) or equivalent pressed into pallets and assembled into fuel rods.

Intensity of nuclear reaction is controlled by control rods that can be inserted into reactor from above. These rods are made from neutron absorbing material and depending on the depth of insertion hinder the chain reaction. If there is an emergency, a reactor shut down can be performed by  infill insertion of control rods.

Primary cooling circuit

As stated above, water in primary circuit is kept under constant pressure to avoid boiling. Since the water transfers all heat from the core and is irradiated, integrity of this circuit is more critical .in this circuit  four sub systems, can be  distinguished .

Reactor : water from through fuel rod assemblies and is heated by nuclear chain reaction.

Volume compensator :  to keep water under consistent but  under control pressure employing self regulation of saturated steam water interface and by mean of electrical heating and relief valves.

Steam generator  :  in the steam generator, heat from primary coolant water is used to boil water in secondary circuit.

Rump  ; The pump ensures proper circulation of water to ensure safety primary components  are redundant.

Secondary circuit

The secondary circuit also consists of different sub systems.

Steam generator  : secondary water is boiled taking heat from primary circuit . Before entering the turbine remaining water is separated from steam so that steam is dry.

Turbine :  the expanding steam drives turbines, which connects to electrical generator. The turbine is spit into high and low pressure sections. To prevent condensation (water droplet at high speed damage the turbine blades) . Steam is reheated between these sections. Reactor of VVER-1000 type deliver 1 GW of electric power.

Condenser   : the steam is cooled and allowed to condense, shedding waste heat into a cooling circuit.
Deaerater  ;  Removes gasses from coolant.

Pump   :  The circulation pumps are each driven by their own steam turbine.

To increase efficiency  of process,  the steam from turbine is taken to reheat coolant before decelerator and steam generator  . Water in this circuit is not supposed to be radioactive.

Cooling circuit

The cooling circuit is open circuit diverting water from outside reservoir such as lake or river. Evaporating cooling tower, cooling basins or ponds exhaust heat from generation circuit, releasing it into environment. In addition to generating electricity most VVER s have capacity to supply heat for residential and industrial use.

Safety barriers

A typical design features of nuclear reactors is layered safety barriers preventing escape of radioactive material.VVER reactors have four layers.

Fuel pellets : Radioactive elements are retained within the crystal structure of fuel pellets.
Fuel rods     : The zirconium tubes provide a further barrier resistant to heat and high pressure.
Reactor shell  : A massive steel shell encase the whole fuel assembly hermetically.
Reactor building  : The concrete containment building that encases the whole first circuit is strong enough to resist pressure surge a breach the first circuit would cause.
Currently operating Russian VVERs are inherently safe design than RBMK reactor of Chernobyl disaster. The Soviet  union opted to construct graphite-moderated RBMK series nuclear reactors without containment structure on grounds of costs as well as relative ease of the re-fueling RBMK reactors. An RBMK reactor can be re fueled while still operational compared to VVER which needs to be shut down. Many levels of protection and containment have both been proposed and constructed for RBMK and  VVER reactors.

Operation life of VVER 1000
When first built design was intended to be operational for 35 years. Many VVER plants are now reaching and passing 35 years mark. More recent design studies have  allowed for an extension of life time up to 50 years with replacement of equipment. New VVER will be name plated with extended life time.
In 2010 the oldest VVER-1000 at Novo Voronezh was shut down for modernization  to extend life of additional 30 years . The first to undergo such an operating life extension. The works include the modernization of management protection and emergency systems and improvement of security and radiation safety systems.

VVER 1200
The VVER-1200 is an evolution of VVER 1000 being offered for domestic and export use. Specification include 1200 U.S. dollars per KW electrical capital cost, 54 month planned construction and expected 50 years life time at 90 per cent capacity factor.  The VVER 1200 will produce 1200MWe of power.

Safety features include containment building and missile shield. It will have fuel emergency systems, that include emergency core cooling systems, emergency back diesel power supply, advanced refueling machine, computerized reactor control systems back up feed water supply and reactor SCRAM system. The nuclear reactor and associated systems will be hosted in one single building and will another building for turbo generator. The main building will comprise the reactor ,refueling machine and diesel back up power supply ,steam generators and reactor control system.

If VVER 1200 experiences a loss of coolant accident or loss of power accident the turbo generator coast down for 30 seconds, during which time a shut down can be initiated using residential power  in the system. Further emergency power is available from back up set of diesel generators kept on stand by to maintain cooling flow reactor. This reactor design has been refined to optimize fuel efficiency

westinghouse AP 1000 reactors

Westinghouse AP 1000 reactor

Westinghouse Electric Company ( WEC) is a nuclear power company offering wide range of nuclear products and services to utilities thought the world, including nuclear fuel , service and maintenance, instrumentation and control and advanced nuclear plant design. Fifty years ago Westinghouse helped to build the first nuclear plants in U.S. Today  there are more than 440 nuclear reactors world wide with net generating capacity of more than 368 Giga watts with 30 nuclear projects under construction Westinghouse technology is basis for approximately half of these reactors, giving Westinghouse the world’s  largest installed base for operating plants. Westinghouse world head quarters is located Cranberry township , Pennsylvania in US. Toshiba corporation is its major owner.

Nuclear power is proven safe, plentiful and clean source of power generation Westinghouse Electric Company the pioneer and global leader in nuclear power plant design and construction is ready with the AP 1000 Pressurized Water Reactor (PWR). It is only the generation 111+ reactor design certification from U.S. nuclear regularity commission (NRC).The AP 1000 based on proven performance of Westinghouse designed  PWR s in an advanced 1154 MW e  nuclear power plant that uses forces of nature and simplicity of design  to enhance plant safety and operations and reduce construction cost.

Westinghouse electric co once again sets a new industry standard  with AP 1000TM  reactor. Historically Westinghouse  plant design and technology, have forged the cutting edge of world wide nuclear technology. Today about 50 per cent world’s  440 nuclear plants are based on Westinghouse technology.

AP 1000 is the safest and most economical nuclear power plant available in the world wide commercial market place, and is only the generation 111+  reactor to receive design certification from U.S. nuclear regularity commission. The  AP 1000 features proven technology innovative passive  safety systems  and offers
. Un equaled safety
. Economic competitiveness
. Improved and more efficient   operations
AP 1000 features proven technology of major components used in current Westinghouse -designed plant proven reliable operating experience over 50 years. These components include
. Steam generator
. Digital instrumentation and control.
. Fuel
. Pressurizes
. Reactor vessels

Simplification  was major design objective for AP1000. The simplified plant design includes overall safety systems, normal operating systems the control room, construction techniques , and instrumentation and control systems. The result is plant that is easier and less expensive in operate and maintain.

AP 1000 design saves money and time with accelerated construction time period approximately 36 months, from pouring first concrete to loading of fuel . Also innovative AP 1000 features
. 50 percent fewer safety related valves
. 80 percent less safety related piping
. 85 percent less control cables
. 35 per cent fewer pumps
. 45 per cent seismic building volume

Improved nuclear power plant performances mean more electricity for less money. The AP 1000 reactor has several design features that improve plant production and worker safety.
. Eighteen month fuel cycle for improved availability and reduced overall fuel costs
. Significantly reduced maintenance, staging and testing and inspection requirements
. Reduced radiation exposure and less plant waste
. Sixty year design life .
Operational maintenance

Operating nuclear power plants in U.S. are already competitive  producers of electricity to coal fired pants. This enhanced by the fact that fuel cost accounts for about 25 per cent of production cost for nuclear power ,while remaining 75 per cent of production cost  is the fixed cost of operation and maintenance.  That means that nuclear power production is much less sensitive to changes in fuel costs than fissile fuel proven plants, where fuel costs can account 75 per cent or more the production cost.

And because of the smaller ,simpler plant design the AP 1000 requires less equipment and infrastructure to test and maintain the plant. Lower operating and maintenance requirements also save money in the form of smaller staffs. The selection of proven components ensure a  high degree of reliability to reduce maintenance.Standardization of components reduces spare part inventories, training requirements , and shorter maintenance times are achieved. Additionally built in testing is provided for critical components.

Passive -core cooling system

Power reactors of this general type continue to produce heat from radioactive decay production even after the main reaction is shut down, so it is necessary to remove this heat to avoid melt down of reactor core and possible escape into containment or very unlikely , beyond the containment. In this design Westinghouse’s passive core cooling system (PCCS) use less than twenty explosively operated and DC operated valves which must operate within first 30 minutes. This designed to happen even if reactor operator take no action. The electrical system required for initiating  the passive systems does not rely on external or diesel power and valves don’t rely on hydraulic or compressed air systems.

If the active process to turn on the passive system works on design is intended  to passively remove heat for 72 hours, after which PCCS gravity drain water tank ,must be topped up for as long as cooling is required.

NRC  has questioned the durability of AP 1000 reactor’s shield building in face of severe external events such as earth quakes, hurricane, and airplane collisions. A  U.S. nuclear consultant engineer has criticized the AP 1000 containment design arguing that in case of design basis , accident, it would release radiation, Westinghouse has denied the claim. The NRC anticipates completing the overall design review for AP 1000 around September 2011.

General Electric nuclear reactors and advantages

General Electric nuclear reactors

In 1990, Nuclear Regularity Commission (NRC) certified GEH’s( GENERAL ELECTRIC and HITACHI) ABWR (Advanced Boiling Water Reactor) in U.S.the first  and advanced generation 111 design (a U.S. Department of Energy classification to begin operations in globally. ) Today  four ABWR plants have been completed and put into commercial operation. An  additional ABWR plants are under construction, with four more plants in planning stage . ABWR is the foundation of GEH’s advanced reactor portfolio.


GEH is the last remaining U.S. vendor of light water reactor (LWR) technology owned by a U.S. company has most current on going construction experience, is construction ready and believes in getting things right new build nuclear energy is not a splint for incentives (U.S.)but rather a more than 60 years technology commitment.

ABWR

The advanced boiling water reactor (ABWR )is foundation of GEH,s nuclear reactor portfolio. The design is available today for immediate generation needs of 1500 MW, providing technology and schedule certainly along with competitive economics.

These reactors were originally designed by Alis- Chalmers and General Electric (GE). The GE design survived, whereas all Alis -Chamres  are shut down. The first GE  U.S. commercial plant was at Humboldt Bay near Eureka in California . Others suppliers of BWR  design  world wide have included ASEA-Atom,Kraftwerk Union, Hitachi. Commercial BWR reactors may be found in Finland, Germany, Japan, Mexico ,Netherlands , Spain , Sweden, Switzerland and Taiwan. Japan and Thailand have newest BWR units.

The BWR reactor typically allows bulk boiling of water in reactor. The operating temperature of this reactor is approximately 570 F degrees producing steam at a pressure of about 1000 pounds per square inch. Current BWR reactors have electrical outputs of 570 to 1300 Mwe. These units are about 33 per cent efficiency.

ESBWR

GEH’s next evolution of advanced BWR technology is ESBWR. It utilizes more locational options, excellent economics and operational flexibility that ultimately increases plant availability.

A GEH designed generation 111+ reactor is currently in U.S. design certification process. The design control document was docketed by NRC in 2005 and referred to Combined Construction and Operating License  (COL) application was submitted in 2007.

ESBWR is an evolutionary design the latest long time of proven , GEH, BWR  reactors. ESBWR employees passive, safety design features. It includes further design evolutions that simplify the reactor, allowing faster construction and lower costs.

Primary benefits and features of ESBWR include
.simplified design features
. Passively removes decay heat, directly to heat directly to atmosphere
.. 11 systems are eliminated from previous design
. 25 per cent fewer pumps, valves and motors

Passive design features reduce the number of active systems, increasing safety .
. It is 11 times more likely for largest asteroid near the earth impact the earth over next 100 years than ESBWR operational event to result in release of fission products to the environment .

Incorporate of features used in other operational proven reactors, including passive  containment cooling ,isolation condensers,  natural circulation  and debris  resistant  fuel.

GEH is ready to support utilities looking to build an ESBWR power plant with well established  global supply chain.

Fuel cycle

Global nuclear fuel (GNF)  a joint venture of GE Hitachi  and Toshiba designs and manufacture fuel necessary to operate nuclear power plants with highest standard of performance.

GNF is dedicated to design, development and manufacturing of reliable nuclear fuel for boiling water reactors (BWR ) nuclear power plants. GNF is comprised of manufacture  of fuel service facilities to the United  States, Japan as well as Spain through its joint venture with ENUSA. GNF offers customized nuclear fuel solutions to fit the specific energy need their customers.

As increased fuel performance becomes the industry standard there are also greater expectations on fuel reliability. To meet these demands GNF is committed to driving reliability for GE’s  customers through defense in depth program. With the goal of achieving highest level fuel performance for boiling water  reactors (BWR) defense -in depth is broad based program focused on significantly reducing the criticality  important issues nuclear power plant operations face when it comes to fuel.

Superior fuel reliability through best in class filtering technology. Optimized design and performance.

The enhanced design of GNF2 fuel assembly-based on pioneering technologies developed by GNF.provides  customers with improved fuel utilization and increased performance and reliability.

In addition to increased out put and reduced fuel costs, GNF2 advanced design offers latest technology in corrosion and debris   resistance.  The advanced  debris filter , the defender TM is now standard on GNF2 fuel assembly-increases reliability and filtration to the best available in today market.

GNF2 fuel assembly has undergone  rigorous testing and is expected to be even more reliable than  other fuel designs-preventing more fuel failures than any other design- to the standard defender filters.

Increased out put, reduced fuel cost

To meet customers need in a demanding market, GE designed  GNF2 to deliver increased energy out put-while reducing overall fuel cycle costs. This enhanced design will save money by reducing the total amount of uranium and average enrichment in fuel reloads. 

india nuclear scenario

India nuclear scenario

The Indian nuclear scene has acquired a new look.

NPCIL (nuclear power corporation of India ) targeted 63000 MW of nuclear energy by 2032 which is about 35 percent of total power country’s capacity (present India power generating capacity is 1,62,000 MW) projecting nuclear power as largest ingredient.

The enlarged 2032 target achievable once planned 30,000 MW advanced light water reactors to be imported during next two decades from leading powers Russia, France,U.S. Japan and Korea.

Indigenous construction of 700 Mwe  pressurized heavy water reactors (PHWRs) mapping out by NPCIL and one chain of 500 MW fast breeder that are to follow the pro to type 500 MW of FBR under construction at Kalpakkam under implementation.

These projects are formidable challenges both light water reactors and a chain of indigenous PHWRs and FBRs. Now has 20   nuclear projects operating mostly on pressurized heavy water.

The scenario on the ground shows vibrant activity. NPCIL is pushing a head with construction of fresh chain of indigenous built PHWRS. After having up graded reactor design from 220Mwe to 500Mwe at Tarapur 3 and 4 reactors upcoming built up is  700Mwe  each construction has been launched four 700MWe reactors at two sites where some best PHWRs in the world have been  built by NPCIL in Kakrapar in Gujarat and Rawatbhata in Rajasthan . Here construction of Kakrapar 3 and 4 and Rajasthan 7 and 8 have been launched. Together there four reactors and 2800 Mwe nuclear power is added to present capacity of 4780 MWe. The four reactor expected to be operational zed in 2015-2016.

Nuclear projects under construction          rector type   capacity in MW             expected commissioning

KNPP-1 Kundankulam  Tamilnadu          LWR             1000                             March 2011
KNPP-2  Kundankulam  Tamilnadu          LWR             1000                             Dec-2011
KAPS-3  Kakrapar          Gujarat             PHWR             700                             June -2015
KAPS-4  Kakrapar          Gujarat            PHWR              700                            Dec-2015
RPAS-7  Rawatbhatla      Rajasthan        PHWR               700                            June -2016
RPAS-8 Rawatbhatla       Rajasthan        PHWR               700                            June -2016

Proposed project

Jaithapur                          Maharashtra    EPR                  3200                             2017


For faster nuclear power addition in parallel to the indigenous three stage program additional ties  based on imports ,have been included. Two light water reactors (LWR) of 1000 Mwe each are under construction at Kundankulam ( as mentioned above) in technical co-operation with Russia federation.

The possible nuclear capacity beyond 2020 has been estimated by  Department of Atomic Energy (DAE) in energy terms, the integrated energy policy of India estimates share of nuclear power in total primary energy mix to be between 4 per cent to 6.4 per cent in various scenarios in the year 2031-32. DAE estimates to be about 8.6 per cent by year 2032.

Jaithapur preliminary work at this nuclear site likely to commence shortly, meant for French company AREVA ‘s EPR ( EUROPEAN PRESSURIZED REACTOR ) each generating 1600 Mwe capacity. Environmental clearance has been for proposal.

Kovvada in Andhra Pradesh is host U.S. technology reactors possibly GE-Hitachi  ABWR or ESBWR boiling water reactors. These are among advanced 1400 Mwe reactors. Environmental clearance has been given.

Mithi Virdi   in Gujarat is host  U.S. technology Westinghouse AP 1000 reactors. Here also project activities initiated, environmental clearance has been given .

Haripur in West Bengal is host Russian WER-1200MWe units. However resistance from political parties putting doubt the future of this project.

Hectic and eventful negotiations are billed 2011 to give final shape to India’s  induction of these advanced reactors.

The progress with Westinghouse and General Electric has been much less compared to France and Russia. There internal problems in U.S. about nuclear power and democrats do not seem to be enthusiastic either . We want U.S. industry to speed up negations with India early commissioning planned projects.

There are other problems. India passed nuclear liability bill  recently . But liability issue is an elephant in a room. Russia ,Japan, South Korea ( reactor of Westinghouse or America design ) which means they two will want liability issue to be clarified before going ahead with any formal negotiations. As U.S. concerned it is not agreeable totally to liability bill.

India has finally signed a Convention that rules the financial liability of civil nuclear operators and supplier world  a step that is expected to make it easier for foreign suppliers to do business here.

The Convention on Supplementary Compensation (CSC) was signed at International Atomic Energy Agency (IAEA)head quarters Vienna recently a move that has been long sought by U.S. to reassure its supplier to enter Asian nations expanding nuclear market.

U.S. companies are believed to be wary of entering India’s 150 billion dollars nuclear power market due to India’s  enacted nuclear liability law which extends the liability in the event of accident to suppliers.

NPCIL should aggressively and optimistically negotiate in a phased manner with foreign nuclear suppliers and convince them to start negotiation  and construction of above nuclear power plants to enable to reach target 63000 MW. Nuclear power by 2032.

The following are suggested for achieving the target.

1. Renegotiation of nuclear liability bill and enacting amendment to bill to attracting nuclear reactor suppliers.
2.Enter civil nuclear energy deals with Japan and South Korea.
3.Arrangement and planning of finances phased manner for nuclear reactor purchase .
4.Adopting right latest imported reactor technology (LWR) with condition that reactor supplier must supply uranium long-term supply for reactor continuously running and producing nuclear power.
5.Development of thorium based nuclear reactors.
6.indigenous development of heavy water reactors in addition to development of fast breeder reactors.
7.Environmental site clearances by continuously negotiating with land owners by offering safe environmental protection polices and attractive compensation packages as nuclear fuel is a clean source of energy .

india thorium based fast breeder reactors

Fast breeder nuclear reactors

India developing thorium based fast breeder nuclear reactors

A team of scientists  at a premier Indian nuclear facility has made theoretically design of innovative reactor that can run on thorium-available in abundance in country- and will eventually do away with  the need for uranium.

But the project largely depend upon the U.S. playing the ball. The novel fast thorium breeder reactors (FTBR) being developed by V. Nathaniel   and his team at Bhabha Atomic Research Cent re( BARC) in Mumbai has received global attention after paper was submitted to the International Conference on Energy Nuclear Energy Systems (ICENES) at Istanbul.

Power reactors of today mostly use fissile fuel called uranium (U- 235), whose fission releases energy and “ ‘spare neutrons that maintain the chain reaction. But only seven  out of 1000 atoms naturally uranium are  of this type. The rest are “ fertile “  meaning they cannot fission but can be converted into fissionable Plutonium  by neutrons released by U-235.

Thorium is three times more abundant in earth’s crust than uranium but was never inducted into reactors because-unlike uranium-it has no fissionable atoms to start the chain reaction.

But once the world’s uranium run out, thorium and depleted uranium discharged by today’s power reactors-could form “fertile base “ for nuclear power generation, BARC scientists claim in this paper.

They believe this FTBR is one such candidate reactor that can produce energy from these two fertile materials with some help from fissionable Plutonium as “Seed “ to start fire.

By using judicious mix of “seed “ plutonium and fertile zones inside core ,the scientists show theoretically that their design can breed not one but two nuclear fuels-U-233 from thorium and plutonium from depleted  uranium-within the same reactor.

This totally novel concept of fertile-to fissionable conversion has prompted its design to christen their baby the fast “Twin ’ breeder reactor.

This calculations show the sodium cooled FTBR , while consuming 10.96 tonnes  of plutonium   to generate 1000 MW of power, breeds 11.44 tonnes plutonium  and 0.88 tonnes of U-233 in a cycle length of two years. At present there are no internal fertile blankets or fissionable breeding zones in power reactors operating in the world, the paper claims.

The concept has won praise from nuclear scientists elsewhere. “ core heterogeneously  in best way to help high conversion “ says Alexis Nulter  a French nuclear scientist at LPSC reactor physics group in Grenoble thorium based fuels and fuel cycle have been used in the past and are being developed  in a few countries but yet  to be commercialized .

France is also studying a concept of “molten salt reactor” where the fuel is in liquid form, while U.S. 
Considering a gas cooled reactor using thorium. McLean Virginia -based thorium power limited  of U.S. has been working nuclear engineers and scientists of Kurchator institute of Moscow for over decade to develop designs that can be commercialized

But BARC’s  FTBR is claimed to be first design that truly exploit’s the concept ‘breeding “ in a reactor that uses thorium. The hand fuel of fast breeder reactor (FBRs) in the world today including one in India building at Kalpak am near Chennai -use plutonium as a fuel.

These breeders have to wait until enough plutonium is accumulated through reprocessing of spent fuel discharged by thermal power reactors that run on uranium.

Herein  lies the rub

India does not have sufficient uranium  to build thermal reactors to produce  plutonium needed for more FBRs of Kalpak am type. The India -U.S.civil nuclear deal  will enable India  to import uranium fuel and reprocess spent fuel to recover plutonium for FBRs.

Jaganathann design is one way of utilizing thorium and circumventing the delay  in building plutonium -based FBRs says former BARC director P.K. Iyyengar .

Meanwhile India’ s 300,000  tonnes of thorium reserves-the largest in world-the beach sand of Kerala and Orissa states are waiting to be tapped. The BARC scientists say that thorium should  be inducted into power reactors when uranium is still available, rather  than using after it is exhausted.

But FTBR still needs an initial inventory of plutonium to kick start the thorium cycle and eventually to generate electricity.

“he US and Russia  have piles of plutonium from dismantled nuclear weapons” Iyyengar told adding                                  ‘” they should allow as to borrow this plutonium need to start our breeders. We can return material after  we breed enough.

India first fast breeders

India’s first 40 Mwt fast breeder test reactor (FBTR) attained  criticality on 18th October 1985.

India becomes the six nation having technology to build and operate FBTR beside U.S., U.K. France, Japan and USSR.

The unique features of Indian FBTR are
1. Indigenous developed U-PU carbide fuel rich in PU.
2. Design development and fabrication of all machinery, peripheral units and materials are by Indian scientists in close co-ordination with industry.

Status : Initial operational problems sorted out and reactor operates smoothly at a steady power level of 10.5MWt maximum possible power out put owing to small core.

Future plans  : Based on design setting up and operation FBTR has provided rich experience and immense information with liquid metal cooled  fast breeder reactor technology and also confidence to embark upon the design of 500 Mwe  pro to type fast breeder reactor (PFBR) at Kalpakkam .

At forefront of nuclear power research is 500 MW prototype fast breeder reactor (PFBR)being constructed at Indira  Gandhi Center for Atomic Research (IGCAR) Kalpakkam at Tamilnadu. An FBR requires high speed neutrons to produce fissionable material that can produce energy. For the development of atomic energy, India’s  reactors are based on heavy water but they use natural uranium as a fuel and India has limited uranium resources and cannot import uranium because global sanctions. So capacity expansion for heavy water restricted to 10,000 Mwe. Explains S.Balder Raj  director IGCAR “ FBRs beside fission of uranium 235, there is gain fuel conversion of 99.3 per cent uranium 238 to plutonium 239 which turn fissionable. The effective  utilization of uranium resources goes up in FBRs and India achieve respectable capacity by 2020.

But FBRs generate too much heat. To remove it liquid sodium is used, unlike conventional reactors that use water. Since sodium burns on contact with air or water  FBRs are susceptible to fires and shut downs. For instance the French Super phoenix reactor operated for less than one year in its first 10 years. But Raj confidently says that “ there is 300 years of experience in FBRs globally and India has 30 years  experience  . There is nothing to hint that technology is not doable “ if all also well the PFBR-a cost of 3492 crores will generate electricity in 2011 and supply power RS 3.20 per unit. By 2020 four  FBRS of 500 Mwe each are envisaged.

Readers of this blog may give your opinion in comment column for improving my future blogs.   

india nuclear fuel reprocessing

India nuclear fuel reprocessing

India on Friday look a giant leap into nuclear  sector , rocketing  from 10 tonne fuel  reprocessing facility to massive high tech 100 tonne unit at Tarapur which was inaugurated by Prime Minister Manmohn Singh.

Sri Kumar Banerji chair man of atomic commission described it as a land mark event. It was the first unit under a recently constituted Nuclear Recycle Board.

Known as the power reactor fuel processing plant, its role is to reprocess spent fuel from  Kakrapur Rajasthan and Narora atomic power plants. Once spent fuel reaches the plant Tarapur, it goes through a process known as chopping and dissolution , before under going chemical process and then it is stored. The first reprocessing facility was commissioned in 1975 at Tarapur Bhabha  Atomic Research Cent re officials said the process is carried out in four heavily shielded  special cells and involves the separation of Plutonium and uranium.

Present there are four reprocessing plants in country one at BARC in Trombay , another at Kalpak am near  Chennai and two at Trombay . Another unit will be commissioned at Kalpak am in 2013 an integrated facility has been planned at Tarapur, though no time frame has been laid down.

Banerji said the advantage of this integrated facility is that various activities relating to reprocessing can be carried out in a single area . It will also deal with critical issue of waste management. He said present spent fuel in vault at Tarapur, which is one -fourth size of foot ball field with a capacity to accommodate two 540 me reactors. “ we are looking for a geological repository where the waste can be permanently stored. “ he said. 

In a presentation to Prime Minister , BARC director R.K. Sin ha  said without reprocessing only 47,000 mw of nuclear energy may achieved by 2050. Official said  but with reprocessing capacity the target is nearly 60,000 MW .

“ Reprocessing  spent fuel is key to three stage indigenous nuclear power program .It is essential in the transition to the second stage of fast breeder reactors which we have begun and subsequent third stage using thorium in advanced reactors.”

Reprocessing spent fuel will also ensure that  we are better able to manage the waste which are by products of nuclear fuel cycle “ Prime Minister  said.

According to PM , atomic energy program of India represented important and significant step towards energy self reliance and energy security “

Singh said India has opted for closed fuel cycle taking account the modest resource of uranium in the country. Therefore the growth capacity nuclear power generation potentiality hinges on the growth of fast breeder reactor program  “ through the third stage of nuclear power program India will be capable of providing safe, sustainable and clean energy for several countries.”    

latest nuclear reactors

Latest nuclear reactors 

The next two generations of nuclear reactors are currently being developed in several countries .

The first ( 3rd generation  ) advanced reactors have been operating in January 1996. Late 3rd generation  designs are now being built .  Newer advanced reactors have simpler design  which reduce capital cost. They are more fuel efficient and are inherently safer. The nuclear power industry has been developing and improving reactor technology for more than five decades and starting to build the next generation of nuclear power reactors to fill technology development.

Several generation of reactors are commonly distinguished. Generation 1 rectors were developed in 1950-60 and outside U.K. none are still running today . Generation 11 reactors are typified by present U.S. and French fleets and most in operation elsewhere. Generation 111 ( and 3+) are advanced reactors. The first are in operation in Japan and other are under construction or ready to be ordered. Generation IV design are still on drawing board and will not operational before 2020 at the earliest. 

About  85% of world nuclear electricity is generated by reactors derived from designs originally developed for naval use. These and other second generation nuclear power units have been found to be safe and reliable, but they are being  superseded by better designs.

Reactor suppliers in North America, Japan, Europe Russia and elsewhere have a dozen new nuclear reactor  designs and at advanced  stages of planning, while other are at a  research and development stage.
The third generation reactors have following advantages
. Standardized design for each type to expedite licensing, reduce capital cost and reduce construction cost.
 . Simpler and more rugged design making them easier to operate and less vulnerable to operational upsets.
. Higher availability and longer operating life typically 60 years.
. Further  reduced possibility  of core melt accidents.
. Resistance to serious damage that would allow radiological release  from are air craft impact.
.Higher  turn up to reduce fuel use and the amount of waste.
.Burnable absorbs (poison) to extend fuel life.

The greatest departure from second generation design is that many incorporate passive or inherent safety features which require no active controls or operational intervention to avoid accidents in the event of  mal function and may rely on gravitated, natural  convention or resistance to high temperatures.

Another departure is that some PWR types will be designed for load following. While most French reactors to day are operated in that mode  to some extent,  the EPR design has better capabilities. It will be able to maintain its out put at 25 % and ramp up to full out put at rate of 2.5 % of rated power per minute  up to 60 % out put and 5 % rated out put per minute  up to full rated power. This means that potentially the unit  can change its out put from 25 to 100 per cent in less than 30 minutes though this may be at some expense of wear and tear.

However certification design is on a national bane , and safety based. In Europe  there are moves towards harmonized requirements for licensing. In Europe reactor may also be certified  according to compliance with European Utilities Requirements (EUR) of generating companies, which have stringent safety criteria. The EUR include Westinghouse AP 1000, Gidropress, AES -92, Areva EPR , GE’s ABWR , Areva Kerene and Westinghouse BWR 90.

European regulators are increasingly requires large reactors to have some kind of core Cather or similar device, so that in a full core melt accident is enhanced provision for cooling the bottom of reactor pressure vessel or simply catching any material that might melt though it, the EPR and WER 1200 have core Cather under the pressure vessel, the AP 1000 and APWR have provision for enhanced water cooling.
In U.S. a number of reactor types  have received design certificate and others are in process.
ESBWR   from GE-Hitachi U.S. EPR  from Areva and U.S. -APWR from Mitsubishi. The  ESBWR is on track to receive certificate about September 2017 and the U.S. EPR  in mid 2012. Early in 2008 the NRC (nuclear regularity commission ) said the beyond these three, six pre -application reviews could possibly get under way by about 2010. These include ACR from Atomic energy of Canada (AECL), IRIS from Westinghouse, PBMR from ESKOM and 4S from Toshiba as well as General  Atomic  GT-MHR apparently. However for various reasons these seems to be inactive.

Joint ventures

The major international initiatives have been launched to define future reactor and fuel cycle technology mostly looking further ahead than the main subjects of this presentation.

Generation IV international forum is a U.S. led grouping to set up 2001 which has identified six reactor concepts for further  investigation with a view to commercial deployment by 2030.   

The IAEA international project on innovation nuclear reactors and fuel cycles (INPRO ) is focused more on developing country needs, and initially involved Russia rather than U.S. though  U.S. has joined it. It is now funded through the IAEA budget.

At commercial level by end of 2006 three major western - Japanese alliances had formed to dominate much of world reactor supply market.

.  Areva  with  Mitsubishi Heavy industries (MHI) in  a major project and subsequently in fuel fabrication
. General Electric with Hitachi as a close relationship . GE Hitachi nuclear energy (GEH)
. Westinghouse had become 77 per cent owned subsidiary of Toshiba ( with SHAR group 20 %)

Details of EPR

AREVA  NP (Formerly Frame tome ANP ) has developed a large ( 4590 Mwt  typically 1750 Mwe gross and 1630 Mwe net ) European Pressurized water reactor ( EPR ) which was confirmed in mid 1995 as well as new standard design for France and received French approval in 2004. It is a  4 loop  design derived from German KONVOI types with features from French N4 and expected to provide  power about 10 per cent cheaper than N4 . It has several active safety systems, and  a core catcher under pressure vessel . It will operate flexibility to following   loads, have fuel burn up of 65 GW D/H and high thermal efficiency 37 per cent and net efficiency of 36 per cent . It is capable of using full core load of  MOX. Availability is expected to 92 per cent over 60 years service life. It has four separate redundant safety systems rather than   passive safety .

India signed agreement with French AREVA for  supplying two EPRs  for their plant to be built in Jaithapur in Maharashtra. 

China -nuclear technology

China- nuclear technology

Main land china has 13 nuclear power projects  in operation  25 under construction and more about to start construction soon.  Additional  reactors are planed ,including some of the world most advanced to give more than tenfold increase in nuclear power capacity to 80 G We by 2020 and 200 G We by 2030 and 400 G We by 2050.

china is rapidly  becoming self sufficient in reactor design and construction as well as other aspects of fuel cycle .

Technology  has been drawn from France, Canada and Russia with local development based ,largely French element from Areva. The latest  technology acquisition has been from U.S. ( VIA  Westing House owned by Japan’s Toshiba) and France. The Westing House AP 1000 is the  main basis of technology development in immediate future.

Concerning technology PWR are expected to level off at 200 G We  about 2040 and fast reactors progressively increase from 2020 to at least 200 GW by 2050 and 1400 GW BY 2100 . 

In September 2010 China daily reported that China National nuclear corporation (CNNC) alone plan to invest CNY 800 billion ( 120 billion dollars ) into nuclear energy projects by  2020. Total investment in nuclear energy projects in which CNNC will hold controlling stakes , will reach CNY 500 billion ( 75 million dollars ) by 2015 according to CNNC. In order to fund the expansion targets CNNC nuclear power co Limited 2011 to attract strategic investors.

Although China intends to become self sufficient in most aspects of fuel cycle it relies increasingly on imported uranium as well as conversion, enrichment and fabrication of  services from other countries.

Domestic  uranium mining currently supplies one -half of China’s nuclear fuel needs. Exploration and plans of new mines have increased significantly since 2000, but state owned enterprises have also entered into agreements to acquire uranium resources internationally.

China two major enrichment plants were built under agreements with Russia  in 1990 s, and under 2008 agreement,  Russia will help build additional capacity and also supply low -enrich uranium to meet future needs.

uranium resources and mining

China’ s  known uranium resources 1000,00 uranium tons are inadequate for country needs. Production  840 tons / year including that heap leach operations at several mines in Xingjian region -supplies enough for  about 4000 M We. By international standards China ore are low grade and production has been inefficient.

Increasingly  , uranium is imported from Kazakhstan, Namibia , Niger and most recently from Australia with other sources progressively added.  

China claims break though in nuclear technology

China has claimed  a break though in extracting uranium and plutonium from unspent fuel, saying this would enable country to run its nuclear power plants for three thousand years with existing uranium resources.

After decades of research , china  has made a break though in extracting uranium and plutonium, from spent fuel state run CCTV announced on Monday. It said china plan to set up  60 new nuclear power reactors mostly  1000 M.W. or more  and have nuclear power productivity of around 75 million kilo watt by 2020.

Under the current nuclear power technology only three to four per cent of nuclear fuel can be used. But spent fuel possess much more power and generates new nuclear material during its burn up, but is a bonded after its initial  use.

The new technology will make nuclear materials 60 times more efficient it said. By using the new technology, uranium materials detected in china could fuel the country’s ‘nuclear power plants for up to three-thousand years. Currently they can only fuel plants from 50-70 years the report said.

It was regarded as a significant break though as china which has 13 nuclear power plants rapidly expanding nuclear power base with 23 more mega  plants under construction.

China is also committed to build three more nuclear power plants to Pakistan including a giant Giga Watt. Reactor.

China in the past relied mostly on U.S., European and Japanese companies to build nuclear power plants last couple years more indigenous companies acquired the know how technology to build the mega projects. 

Besides  this China also constructing 23 machine sets to harness nuclear power , the largest among the 57 such sets in world.

Recent report said china is already stockpiling big quantities of uranium to meet future demand. China currently produces around 750 tons uranium  per year. The demand supply gap of uranium is expected to exceed  10,000 tons by 2015 and reach nearly 30,000 tons by 2030 according to local experts.

China is likely to double its uranium purchases to around 5000 MT to build stock piles for new reactors, according to Thomas Neft  a physicist and uranium industry analyst at Massachusetts institute of technology in Cambridge.

Also china uranium development co. limited last year acquired a majority stake in Australian miner energy metals ltd , which has access to large quantity of uranium resources.

Uranium prices have been framed up due to surge in demand and dwindling global proven resources. Add to this also the long gestation time for successfully mining uranium from new finds. 

European Pressurized reactors

European pressurized reactor

French company Areva on December 6 signed Euro 7 billion deal with  nuclear power corporation of India. (NPCIL) for construction of two nuclear reactors - the first in a series of six and supply of 25 years enriched uranium. Areva partnership  with NPCIL plan to build six nuclear EPR ( European pressurized reactor  ) of 165o M.W. each, with first one coming up at Jaithapur in Maharashtra.  Said  Areva CEO  Anne Lauvergeon. She said the financial details of  the deal were yet to be fully worked out.

The European pressurized reactor water  ( reactor PWR design ). It has been designed and developed  mainly by De  Frame tome  (now Areva NP) Electricite   De France and Siemens AG in Germany. This reactor design was called in European Pressurized reactor  and internationalized name of reactor is evolutionary power reactor but is now  supplying name EPR by Areva.

As 2010 four EPR units are under construction. The first two in Finland and  France are both facing costly construction delays. Construction commenced on two additional Chinese units in 2009 and 2010.

In July 2008 the French president announced a second would be built in France due to high oil and gas prices. Penly was chosen as the site in 20009 and  Construction should start in 2012.

The main design objectives of generation third  EPR are increased safety while providing enhanced economic competitiveness though improvements to previous PWR designs scaled up to an electrical power out put of 1650  M.W. e  with thermal power 4500 Mwt. The reactor can use  5 per cent of enriched uranium  oxide fuel, optionally  with up to 50 per cent mixed uranium Plutonium  oxide fuel. The EPR  is the  evolutionary  descendant of Frame tome N4 and Siemens power generation division on KONVOI reactors.

The EPR design have several active passive protection measures against accidents.
. Four independent emergency cooling systems , each capable of cooling down the reactor after shut down  I.e. (300 per cent redundancy.
. Leak tight containment around reactor.
. An extra container and cooling area if molten core manages to escape the reactor.
. Two -layer concrete wall with total thickness 2.6 meters ,designed to withstand impact by airplanes and internal over pressure.

The union of concerned scientists has referred to EPR as the only reactor design under consideration in United States that “ appears to have the potential to be significantly safer and more secure against attack  than today’s reactors.

As far as design concerned these reactor safe with long life  but we have yet to see these EPRs functioning successfully in any country including  China which building these reactors.

uranium and enrichment

Uranium and enrichment

History

For many years, uranium was primarily as a coolant in ceramic glazes, producing colors that   ranged from orange - red to lemon yellow. It was also used for tinting in early photography . Its radio active  properties were not recognized until 1896, and its potential for use an energy source was not realized until middle of 20th century. It is also used in weapon application , and small nuclear reactors to produce isotopes for medical and industrial purposes around world.

Origin of uranium

Small amounts of uranium are found almost every where in soil, rock and water. However  concentrated deposits are normally cover over with vegetates uranium has been mined in Canada ,the south west U.S.,Australia , part of former Soviet Union, Namibia , South Africa  Niger and elsewhere.

Properties of uranium

Uranium is a radio active element that occurs naturally in varying but small amounts in soil, rocks, water, plants, animal and all human being. It is heaviest naturally occurred element, with atomic number 92. In its pure form, uranium is a silver colored heavy metal  that is a nearly twice as dense as lead. In nature, uranium atom exists as several isotopes which are identified by total number of protons and neutrons in the nucleus : uranium U-238, uranium U-235 and uranium  U-234 (isotopes of element have same number of protons with nucleus but different number of neutrons ) . In a tipped sample of natural uranium most weight 99.27 per cent consists of atom of U-238, about 0.72 per cent U-235 and a very small amount (0.0055 per cent by weight ) is uranium U-234

Radio active isotopes of  uranium

The three naturally occurring isotopes of  uranium are each radio active, which means the nuclei spontaneously disintegrate or ‘decay’ radio activity emitted from uranium isotopes consists of Alpha  similar  to visible light except with higher energy and more penetrating power). The rate at which is the nuclei is an isotope sample decay is called activity , which is the  number disintegrated that occur for second. The activity of isotope sample decreases with the time as atoms disintegrate . Each isotope has its own -half life which is the time it takes for half of atoms in a sample of isotope decay and activity of sample to be proportionally reduced.

Uranium -235 and fission

In addition to being naturally radio active, the uranium U-235 isotopes of uranium is capable of fission, the spitting of nucleus into two parts,  triggered by absorption of neutron. When this spitting occurs , consider energy is released, which makes uranium U-235 valuable as a fuel in reactor used to generate electricity and for use in national defense. 

Enrichment process

Using uranium as fuel in the types of nuclear is common in united states requires that uranium enriched so that the percentage of the uranium U-235 isotope is increased, typically to 3 per cent to 5 per cent. Uranium enrichment is a isotopic separation process that increases the proportion of uranium -235 isotope in relation to uranium U-238 in natural uranium.

The enrichment process used in the West involves combining with fluorine to make uranium hexafluoride (UF6) followed by gaseous diffusion . The UF6 out put from gaseous diffusion is into two streams- one in increased, or enriched in its percentage of U-235 and other is reduced or depleted in its percentage of U-235. The  “deflected  UF-6”  after gaseous diffusion the enriched uranium hexafluoride is for further process, while depleted UF-6 is generally stored.

The uranium enrichment process was first developed in the year 1940 as part of Manhattan project.

Gaseous diffusion

In a gaseous diffusion , uranium hexafluoride  is divided into two separate stream and U-235 selectively diffusion s from one  stream to other.

Before processing by gaseous diffusion uranium is first converted from uranium oxide( U308) to hexafluoride (UF6). The uranium hexafluoride (UF6) is heated and converted  from solid to  a gas . This gas is then forced  though a series of compressors and converts that contain porous barriers. Because  uranium U-235 has slightly lighter isotope mass than U-238 , UF6  molecules made with uranium U-235 diffuse  though the barriers at slightly higher rate than the molecule containing uranium  U-238. At the end of process, there are two UF6 stream, with one stream having higher concentration  of U-235 than other, the steam having greater U-235 concentration is referred to as  enriched UF6  while stream that is reduced  in concentration of U-235 is referred as depleted UF6. The depleted UF6 can be converted to other chemical forms, as depleted uranium oxide or  depleted uranium metal.

Centrifuge technique  

The gas centrifuge process uses a large number of rotating cylinders in series and parallel formations. Each cylinder rotation creates a storing centrifuge force so that heavier gas molecule containing U-238 uranium move toward the out side of the cylinder and lighter gas molecule rich in U-235 collect closer to centre. It requires much less energy to achieve the same separation than older gaseous diffusion process, which it has largely replaced and so is the current method of choice and is termed second generation. It has separation factor per stage 1.3 relative to gaseous diffusion of 1.005 which translates to about one -fifth of energy requirements. Gas centrifuge technique produce about 54 per cent of world enrichment uranium.

Low enriched uranium

Low enriched uranium (LEU) has a lower than 20 per cent concentration of U-235 for use in light water reactors  in the world. Uranium is enriched 3 per cent to 5 per cent in U-235. LEU  used in research reactors is usually  enriched  12 per cent to 19.75 per cent in U-235

Highly enriched   uranium

Highly enriched uranium (HEU ) has greater than 20 per cent concentration of U-235  or U-233 . The fission  uranium in nuclear weapon usually contain 85 per cent or more U-235 known as weapon grade
though  a crude in efficient weapon 20 per cent weapon usable. For critical experiments enrich uranium to over 97 per cent has been accomplished.