Nuclear Reactors

Uranium is a common radioactive element used in nuclear power stations to generate energy through a process known as nuclear fission. It provides a sustainable and efficient source of power by splitting atoms and releasing heat energy. Proper handling and containment measures are essential due to its radioactive properties.

Some of the consequences of nuclear leaks and meltowns include radioactive contamination in areas surrounding the leaks. Loss of life, pollution, and even long term damage to the land is also caused by nuclear leaks.

Well, scientists have been researching fusion reactors for over 50 years, but nuclear fusion is much more difficult to achieve than nuclear fission, which is what current nuclear power technology is based on. There are many reasons for this, but while there have been tests and advancements in the field, scientists have yet to a) create a sustainable and stable nuclear fusion reaction and b) create a reaction that has a greater output than input.

If we were to perfect the technology and use it commercially, it would probably give the earth unlimited technology as it would have an energy output similar to that of a star.

This condition is called a meltdown (or core meltdown or nuclear meltdown). The fuel becomes too hot (quite probably due to a loss of coolant accident - LOCA) and it melts, melting its way in turn through the cladding or "protective layer" of metal around the fuel pellets themselves. This dumps highly radioactive spent fuel (and all those nasty radioactive byproducts of fission - the fission fragments) into the primary coolant to be circulated around the plant. This is a major accident, and emergency shutdown procedures - and emergency cooling - will probably have to be initiated to cool the core enough to keep the problem from getting completely out of control and resulting in the so-called China syndrome. In this accident scenario, the superheated core melts its way through the reactor vessel and through the thick concrete floor of the reactor building and into the ground spreading the radioactive contamination outside the containment building itself. Note that the core continues to generate huge quantities of heat for hours after shutdown (even in a melted condition), so failure of the primary cooling system will result in a disaster if emergency cooling isn't effective.

The nuclear reactor of a nuclear power plant is usually considered to be the core and the pressure vessel in which it is encased. The control rods, which are in the core (and pulled some or all of the way out to run the reactor) have their associated rod drive motors on top of the pressure vessel. Instrumentation ports are up there, too. All of these things are generally considered to be the "nuclear reactor" portion of the primary system in the plant. A link is provided to a picture posted at Wikipedia. It has a portion of it colored to show the reactor core, but the pressure vessel is "cut away" to view the core. The control rods (#1 in the drawing) are shown as being on top. That's incorrect. The rod drive motors and control rod lead ("leed" and not "led") screws are up there. (The lead screws connect the control rods, which are down in among the fuel bundles, to the rod drive motors, which are up on top of the pressure vessel's cap.) The rods belong in the core, or in the area above the core when they are pulled out. The whole thing, the core, the vessel, and the rod drive motors as well as the instrumentation on top are considered to be the "nuclear reactor" in a power plant. If asked to identify the picture, the most correct response is probably, "It's a cut-away drawing of a nuclear reactor." That means everything in the picture is part of the nuclear reactor.

India primarily uses uranium and thorium as radioactive elements for its nuclear reactors. Uranium is the primary fuel for Pressurized Heavy Water Reactors (PHWRs), while thorium is used in some reactors as a fertile material for breeding fissile uranium-233.

Usually Uranium 235 but sometimes Plutonium 239

The KAMINI (Kalpakkam Mini) reactor is a Uranium-233 fueled, demineralized light water moderated and cooled, beryllium oxide reflected, low power nuclear research reactor. It is located in the post irradiation examination facility of Radio Metallurgy Laboratory, Indira Gandhi Centre for Atomic Research, Kalpakkam, India. A link is provided to the Wikipedia article.

There are no hazards from nuclear power stations. However, these stations need careful design, good quality during installation, skillful operators, good maintenance, and application of good safety rules during operation and when dealing with nuclear waste.

The Three Mile Island incident in 1979 was a partial meltdown resulting from equipment malfunctions and operator errors, with no immediate fatalities and limited off-site impact. In contrast, the Chernobyl disaster in 1986 was a full-scale meltdown caused by a flawed reactor design and operator errors, resulting in immediate deaths, widespread radioactive contamination, and long-term health and environmental consequences.

In brief, both accidents involve gross failure of a nuclear reactor. The two reactors are of different types, so there are some things that are unique to each plant. Both had the reactor cores damaged catastrophically. And in both cases, radiation was released ourside fuel element cladding and outside containment barriers. What is different is that in the Chernobyl disaster, the atomic pile caught fire. I was built using graphite blocks for moderators. At Three Mile Island (TMI), there was no fire. The radiation released at TMI was some nasty stuff including fission fragments from failed fuel element cladding, but it was released in limited quantities. TMI was an accident. In Russia, things were different. It was a disaster. At Chernobyl, as the core burned, massive clouds of highly radioactive fission byproducts (from the failed fuel elements) were caught up in the fire column and swept aloft with the smoke and heat. This caused the surrounding area to have to be evacuated and some of it was actually abandoned. The small city of Pripyat became a ghost town. This newly constructed community of about 50,000 or so was abandoned. People just walked away. They literally left everything behind and departed with just the clothes on their backs. There were a number of fatalities at Chernobyl, and none at TMI. Some reactor workers and a number of emergency personnel responding to the fire died of radiation sickness. And a number of civilians lost their lives within a few weeks of the accident. One account logged by a helicopter pilot (several choppers dumped water on the fire from aloft) said that in the night, the column of smoke and debris from the fire glowed in the darkness due to the radioactivity. Helicopter pilots were among those who died as a result of their heroic efforts to douse the flames. Links are provided to relevant Wikipedia articles.

The "nuclear reactor time bomb" theory was popularized by author and scientist Amory Lovins in the 1970s. Lovins argued that nuclear reactors posed safety risks and could lead to catastrophic accidents or intentional sabotage, likening them to a ticking time bomb.

Not from nuclear effects, though any large industrial plant built in a rural area must have some effect just due to the buildings where previously it was open country

First you have to better define working. If "working" means having nuclear material that can actually do something then you don't. If you try you'll probably at best end up in jail and at worst giving yourself radiation poisoning. However if what we define as working gets some play room then there are a few designs out there that work. Most involve some way to boil water (preferably electrical, like a cheap espresso machine as they have safeties) and then turning a turbine to make electricity. You just have the boiler hidden inside a containment structure like a real reactor and print off a picture on what a core should look like.

I'm currently looking into this for outreach programs and will post my findings.

No, most of India's reactors are PHWR (Candu type) reactors. There were two GE BWR's before this. Russia is supplying a new station based on PWR reactors, and a fast reactor is also under construction. No Chernobyl type reactors exist or are planned (RBMK type).

Probable USA has the most plutonium.

Yes, they are man-made.

fission

Probable you think to a breeder reactor; this type of nuclear reactor produce more fissile material than it consumes.

Tianwan Nuclear Power Plant was created in 2006.

Although they have the nuclear material that could be deviated for nuclear weapon production but Ukraine has neither the motivation nor the political/economical will to make nuclear weapons.