Nuclear Safety

>> Wednesday, February 29, 2012

Now, I will explain about nuclear safety… how about you? Do you think it is safe to build nuclear power plant in Malaysia? Basically, the three primary objectives of Nuclear Safety Systems as defined by the Nuclear Regulatory Commission are to shut down the reactor, maintain it in a shutdown condition and prevent the release of radioactive material during events and accidents. There are many aspects we should consider. One from them is defense-in-depth approach. To achieve optimum safety, nuclear plants in the western world operate using a 'defense-in-depth' approach, with multiple safety systems supplementing the natural features of the reactor core. Key aspects of the approach are:
-         high-quality design & construction,
-         equipment which prevents operational disturbances or human failures and errors developing into problems,
-         comprehensive monitoring and regular testing to detect equipment or operator failures,
-         redundant and diverse systems to control damage to the fuel and preventsignificant radioactive releases,
-         provision to confine the effects of severe fuel damage (or any other problem) to the plant itself.

How about nuclear safety when earthquake occur? According to nuclear world website, we find that nuclear power plants are designed with sensors to shut them down automatically in an earthquake, and this is a vital consideration in many parts of the world. Below is the example other country take when earthquake occur:-
-         Japanese, and most other, nuclear plants are designed to withstand earthquakes, and in the event of major earth movement, to shut down safely.
-         In 1995, the closest nuclear power plants, some 110 km north of Kobe, were unaffected by the severe Kobe-Osaka earthquake, but in 2004, 2005, 2007 and 2009 Japanese reactors shut down automatically due to ground acceleration exceeding their trip settings.
-         In 1999, three nuclear reactors shut down automatically devastating Taiwan earthquake, and were restarted two days later.

Nuclear facilities are designed so that earthquakes and other external events will not jeopardize the safety of the plant. Below are the safeties that other countries take into considerations:-
-         In France for instance, nuclear plants are designed to withstand an earthquake twice as strong as the 1000-year event calculated for each site.
-         Because of the frequency and magnitude of earthquakes in Japan, particular attention is paid to seismic issues in the siting, design and construction of nuclear power plants. The seismic design of such plants is based on criteria far more stringent than those applying to non-nuclear facilities. Power reactors are also built on hard rock foundations (not sediments) to minimize seismic shaking.
-         Japanese nuclear power plants are designed to withstand specified earthquake intensities evident in ground motion. These used to be specified as S1 and S2, but now simply Ss, in Gal units. The plants are fitted with seismic detectors. If these register ground during the motions of a set level (formerly 90% of S1), systems will be activated to automatically bring the plant to an immediate safe shutdown.
-         The December 2004 tsunamis following a magnitude 9 earthquake in Indonesia reached the west coast of India and affected the Kalpakkam nuclear power plant near Madras/Chennai. When very abnormal water levels were detected in the cooling water intake, the plant shut down automatically. It was restarted six days later.

One more thing we must take into considerations about nuclear safety is passive safety system. One major feature Japan has in common (beyond safety engineering already standard in Western reactors) is passive safety systems, requiring no operator intervention in the event of a major malfunction. The main metric used to assess reactor safety is the likelihood of the core melting due to loss of coolant. These new designs are one or two orders of magnitude less likely than older ones to suffer a core melt accident, but the significance of that is more for the owner and operator than the neighbours, who - as Three Mile Island showed - are entirely safe also with older types.

Other than that, the Emergency Core Cooling System (ECCS) is one more safety thing to the nuclear. Emergency Core Cooling System (ECCS) comprises a series of systems which are designed to safely shut down a nuclear reactor during accident conditions. Under normal conditions heat is removed from a nuclear reactor by condensing steam after it passes through the turbine. These systems allow the plant to respond to a variety of accident conditions and at the same time create redundancy so that the plant can still be shut down even if one or more of the systems fails to function. In most plants ECCS is composed of the following systems; High Pressure Coolant Injection System (HPCI), Depressurization System (ADS), Low Pressure Coolant Injection System (LPCI), Isolation Cooling System and other else.

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nuclear economics

Nuclear economics

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Why we need nuclear power

>> Tuesday, February 28, 2012


By Stanford L. Levin
Nuclear power is our single most important source of clean energy. Nothing that has happened in Japan changes the necessity and desirability of nuclear power.
Here at home, nuclear power is dependable. Illinois nuclear plants generate electricity over 95 percent of the time, and Ameren's Calloway plant over 92 percent of the time. This is far better than coal or gas plants and the variability of solar and wind power, which are of no use when the sun isn't shining or the wind isn't blowing.
Nuclear-generated electricity is clean energy. Currently, nuclear power provides about 20 percent of the electricity in the U. S. Moreover, nuclear generation, unlike coal, has no carbon emissions and does not contribute to global warming.
Natural gas produces only about half of the carbon emissions as burning coal, but this is misleading. Natural gas is increasingly recovered by a process of hydraulic fracturing, or fracking. Fracking involves pumping sand, water and chemicals under very high pressure to break up underground shale, releasing trapped gas.
Fracking uses lots of water, which is often of limited availability. The chemicals used are not regulated and can be dangerous. They are a threat to water supplies. Fracking gives off methane, and, considering all aspects, using natural gas to generate electricity may actually give off more greenhouse gases than burning coal.
Solar power is losing its environmentally friendly status. Generating significant amounts of electricity requires large-scale solar installations such as those proposed for western deserts with fragile environments. These large installations take a substantial amount of usually public land that is then unavailable for other uses. The eleven major solar projects that have been approved in California and Nevada could be replaced with three or four nu-clear plants with no negative environmental consequences and a lower cost.
Large scale wind farms, those big installations of windmills that one sometimes sees, pose noise and visual pollution issues. They are also hazardous to birds and other wildlife.
Because of their cost and their variable nature, it is simply unrealistic to think that we can rely on solar and wind power to satisfy a major portion of our electricity needs.
Small modular nuclear reactors, similar to those the navy uses successfully in its ships, are being developed for commercial use. These may be less expensive than large power plants, but, more importantly, they can be installed as needed to meet the growth in demand for electricity. They may also be better suited to replacing smaller gas, oil, and coal facilities as they wear out. These modular units, by being matched more closely to increases in demand, avoid the problem of funding a large nuclear plant before all of its capacity is needed.
By most accounts, U. S. nuclear plants are built to a higher safety standard than Japanese plants, including the Fukushima Daiichi plants. The U.S. nuclear industry and the Nuclear Regulatory Commission will learn from the Japanese experience and will make U.S. nuclear facilities even safer.
It would be a mistake to slow down the development of nuclear power in the U. S. Indeed, it should be accelerated. Many sites were designed from more plants that were initially built, so it is not a difficult task to license new plants for these locations. We can contribute to our energy independence, reduce global warming, and generate environmentally friendly electricity, all at a competitive cost.
STANFORD L. LEVIN is emeritus professor of economics, Southern Illinois University Edwardsville. He has also served as a commissioner on the Illinois Commerce Commission, the utility regulatory agency in Illinois, and consults on energy issues in North America and abroad.


Read more: http://thesouthern.com/news/opinion/editorial/guest/article_730435e4-a6bd-11e0-85f5-001cc4c002e0.html#ixzz1nfkWzcRd

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nuclear trivia


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fusion and fission


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Reactor Triga Puspati(RTP)

>> Thursday, February 23, 2012


Reaktor TRIGA PUSPATI (RTP) the only nuclear research reactor in Malaysia. It came into operation in 1982 and reached its first criticality on 28 June 1982. TRIGA stands for Training, Research, Isotope Production and General Atomic. RTP is a pool type reactor, where the reactor core sits at the bottom of a 7-metre high aluminium tank and this is surrounded by a biological shield made of high density concrete. The reactor uses solid fuel elements in which the zirconium-hydride moderator is homogeneously combined with enriched uranium. Demineralised water acts both as coolant and neutron moderator, while graphite acts as a reflector.

The reactor was designed to effectively implement the various fields of basic nuclear science and education. It incorporates facilities for advanced neutron and gamma radiation studies as well as for application, including Neutron Activation Analysis (NAA), Delayed Neutron Activation Analysis (DNA), Radioisotope Production for medical, industrial and agricultural purposes, Neutron Radiography and Small Angle Neutron Scattering (SANS).

reactor
Several experimental facilities are available in the reactor:
  • Rotary Specimen Rack is used for activation analysis and isotope production (e.g. Iridium-192 for industry, Phosphorus-32 for agriculture, Iodine-131, Samarium-153  radiotheraphy agents).
  • Pneumatic Transfer System for the production of very short-lived radioisotopes.
  • Central Thimble in the centre of the core provides space for irradiation of samples at the point of maximum flux.
  • Beam Ports provide tubular penetrations through concrete shield and the reactor tank water, making beams of neutron and gamma radiation available for a variety of purposes.
  • Neutron Radiography Facility (NuR2).
  • Small Angle Neutron Scattering Facility (SANS) for the characterisation of materials on a nano scale.
Application of RTP
Nuclear Research and Development
  • Environmental Science
  • Material Science
  • Archeology and Forensic Science
  • Structural Studies of materials related to metals, ceramics, polymers and biology
  • Life Science
  • Geological Science
  • Nuclear Materials
  • Non-destructive testing
Radioisotope Production
  • Medical diagnostic studies
  • Industrial and agriculture application
  • Medical therapeutic studies
Education and Training
  • Reactor physics and engineering
  • Reactor utilization
  • Radiation source
  • Nuclear safety
  • Reactor Instrumentations
  • Nuclear materials
  • Reactor operations and maintenance
Safety, Security, Safeguards
Safety
  • Reactor Operation licensed by AELB ( www.AELB.gov.my )
  • Governed by National Act and Regulations
  • Adhere to IAEA ( www.IAEA.org ) Code of Conduct on Safety of Research Reactors
  • Internal Safety, Health and Environment Committee overseas reactor safety
  • Only licensed reactor operator allowed to operate reactor
Security
  • Reactor site gazette under Federal and State laws
  • Security measures follow national and international requirements
Safeguard
  • Malaysia party to Treaty on Non-Proliferation of Nuclear Weapons
  • Nuclear Material under International and National Control
For further information, please contact
Director General
Malaysian Nuclear Agency
(attn: Datin Zarina Masood, Manager,
Reactor Operations and Maintenance Section,
Division of Nuclear Power,
Email: Zarina@nuclearmalaysia.gov.my )

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How Nuclear Energy Works

>> Monday, February 20, 2012


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Introduction to Nuclear Technology

>> Saturday, February 18, 2012

We are students from Universiti Tenaga Nasional (UNITEN) , currently taking Introduction to Nuclear Technology (MEHB513) under Assoc. Prof Ir Dr Nasri A. Hamid. 




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About This Blog

We are students of Universiti Tenaga Nasional (UNITEN)

Currently taking Introduction to Nuclear Technology (MEHB513) under Assoc. Prof Ir Dr Nasri A. Hamid.

This blog is our project for this subject.

MEHB 513

Introduction to Nuclear Technology.
This course provides the introduction to Nuclear Technologies, beginning from the fundamental physics to its recent applications in power generation.

Course Objectives

At the end of this course, the students should be able to:
1. Understand the fundamental concepts of nuclear physics, process flow and reactor theory.
2. Explain the nuclear fuel cycle and processes.
3. Understand the applications of nuclear technology in power generation.
4. Appreciate the hazards of radiation and understand the concept of nuclear reactor safety.

  © MEHB513 Nucl3art by Jihardist 2012

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