We begin with the atom. Basic unit of all substance in the known universe. It's a happy little guy, just floatin' through life. Nuclear substances contain special "heavy" atoms such as Uranium (power plants) or Plutonium (bombs). These elements are naturally unstable because of the number of sub-atomic particles they contain. Remember from science class that the atoms are made of postitive neutrons and neutral neutrons in the nucleus, which is surrounded by orbiting negative electrons. When a happy (but naturally unstable) atom of Uranium is hit by a free neutron, it can have several reactions, the most important of which is fission. Fission is when an atom is violently broken apart, releasing tremendous amounts of energy in the form of heat. When the atom is split, its neutrons go onto split other atoms, repeating the process. When fission is not controlled, it creates an explosion, which is how nuclear bombs work. When it is controlled, it simply creates a lot of heat, and is the basis of nuclear power.
Here is our model reactor. Nice, isn't it? Hope it is clear enough for those of you at home. In the center is the reactor core itself. This is where our happy little atoms live. The green things on the side are the reactor coolant pumps, the silver things behind them are the steam generators, and the silver thing above and behind the core is the pressurizer. In the core is the Uranium nuclear fuel, surrounded by the reactor, or primary, coolant. The primary coolant is heated by fission to a very high temperature and pressure (well in the hundreds, the actual numbers are classified though.) Remember that water only boils at 0 degrees (212 degrees Farenheit) when it is at atmospheric pressure. It is imprtant to keep the primary coolant pressure much higher to prevent the water from boiling. Boiling makes steam, and steam does not transfer heat well. The high pressure is maintained by the pressurizer, which has a steam bubble inside it, and allows the Reactor Operator to control pressure by use of electric heaters. The primary coolant is pumped through the core by the reactor coolant pumps through the steam generators to the reactor. In addition to the primary coolant flowing through the steam generators, they also contain secondary coolant, which is boiled into steam. The primary and secondary liquid never physically touch, and heat is transferred from the primary to the secondary through pipes in the generator. Now the primary, which has been cooled by transfering its heat to the secondary liquid, returns to the reactor to repeat the process. The water also acts as a moderator, helping the nuclear process to continue, and the cooler it is, the more the process continues. The core also contains control rods, operated by the Reactor Operator. These contain a neutron absorbing material in order to control the amount of fissions occuring. This prevents the number of fissions or the coolant temperature from reaching a dangerous point.
This diagram shows how the primary and secondary systems interelate. The green on the left is the reactor, flanked by yellow steam generators. The steam exits the top of the generators and goes to the turbines (white, center). The steam spins the turbines, which rotates a generator. Electricity is generated by a conductive metal rotating inside magnetic lines of flux. The turbine generator (red, right) is effectively that. The spinning turbine rotates conductive wires inside a magnet creating electric current, which is then sent to a distribution network to be sent where it is needed. After the steam exits the turbine, it is sent to a condenser, which is cooled by a third system of water. The condenser turns the steam back into water, and drops it down to the feed pumps, which then send it back to the steam generator to repeat the process. And that is nuclear power. Simple, huh?
This is the electrical disribution center for the Oconee Plant. Public Service announcment: Despite what everyone wants you to believe, nuclear power is safe! All reactors in the United States (Chernobyl was Soviet, remember?) have exteremelly strong controls on equipment quality, operator training, routine and emergency procedures, and radiation controls. These are what prevented Three Mile Island from becoming an actual problem, and the controls have only gotten more strict since then. Conventional plants have accidents all the time. Not nuclear plants. They are inherently safe, and are a strong, reliable source of clean energy for many, many, many years.
Ok, so our next stop was the World of Energy museum, located near the Oconee Nuclear Station, seen above. I wasn't really sure about going here since it is a kids museum and we had no kid at the moment, but as it turned out, most of the museum focused on nuclear power and the displays helped me explain (for the first time!!!) to my wife just what it is I do on the sub, without her falling asleep. I will now try to recreate this euphoria for anyone who is interested. And BTW, if anyone from NCIS or whoever reads this, before you give me any s**t, NOTHING on this post is classified. It is basic information that anyone can find, and most of it is from the museum. So I don't want to hear about how this blog is some "security issue." That's bull and we both know it. Ah-HEM. Moving on...
We begin with the atom. Basic unit of all substance in the known universe. It's a happy little guy, just floatin' through life. Nuclear substances contain special "heavy" atoms such as Uranium (power plants) or Plutonium (bombs). These elements are naturally unstable because of the number of sub-atomic particles they contain. Remember from science class that the atoms are made of postitive neutrons and neutral neutrons in the nucleus, which is surrounded by orbiting negative electrons. When a happy (but naturally unstable) atom of Uranium is hit by a free neutron, it can have several reactions, the most important of which is fission. Fission is when an atom is violently broken apart, releasing tremendous amounts of energy in the form of heat. When the atom is split, its neutrons go onto split other atoms, repeating the process. When fission is not controlled, it creates an explosion, which is how nuclear bombs work. When it is controlled, it simply creates a lot of heat, and is the basis of nuclear power.
Here is our model reactor. Nice, isn't it? Hope it is clear enough for those of you at home. In the center is the reactor core itself. This is where our happy little atoms live. The green things on the side are the reactor coolant pumps, the silver things behind them are the steam generators, and the silver thing above and behind the core is the pressurizer. In the core is the Uranium nuclear fuel, surrounded by the reactor, or primary, coolant. The primary coolant is heated by fission to a very high temperature and pressure (well in the hundreds, the actual numbers are classified though.) Remember that water only boils at 0 degrees (212 degrees Farenheit) when it is at atmospheric pressure. It is imprtant to keep the primary coolant pressure much higher to prevent the water from boiling. Boiling makes steam, and steam does not transfer heat well. The high pressure is maintained by the pressurizer, which has a steam bubble inside it, and allows the Reactor Operator to control pressure by use of electric heaters. The primary coolant is pumped through the core by the reactor coolant pumps through the steam generators to the reactor. In addition to the primary coolant flowing through the steam generators, they also contain secondary coolant, which is boiled into steam. The primary and secondary liquid never physically touch, and heat is transferred from the primary to the secondary through pipes in the generator. Now the primary, which has been cooled by transfering its heat to the secondary liquid, returns to the reactor to repeat the process. The water also acts as a moderator, helping the nuclear process to continue, and the cooler it is, the more the process continues. The core also contains control rods, operated by the Reactor Operator. These contain a neutron absorbing material in order to control the amount of fissions occuring. This prevents the number of fissions or the coolant temperature from reaching a dangerous point.
This diagram shows how the primary and secondary systems interelate. The green on the left is the reactor, flanked by yellow steam generators. The steam exits the top of the generators and goes to the turbines (white, center). The steam spins the turbines, which rotates a generator. Electricity is generated by a conductive metal rotating inside magnetic lines of flux. The turbine generator (red, right) is effectively that. The spinning turbine rotates conductive wires inside a magnet creating electric current, which is then sent to a distribution network to be sent where it is needed. After the steam exits the turbine, it is sent to a condenser, which is cooled by a third system of water. The condenser turns the steam back into water, and drops it down to the feed pumps, which then send it back to the steam generator to repeat the process. And that is nuclear power. Simple, huh?
This is the electrical disribution center for the Oconee Plant. Public Service announcment: Despite what everyone wants you to believe, nuclear power is safe! All reactors in the United States (Chernobyl was Soviet, remember?) have exteremelly strong controls on equipment quality, operator training, routine and emergency procedures, and radiation controls. These are what prevented Three Mile Island from becoming an actual problem, and the controls have only gotten more strict since then. Conventional plants have accidents all the time. Not nuclear plants. They are inherently safe, and are a strong, reliable source of clean energy for many, many, many years.
1 comment:
You haven't convinced me on the nuclear stuff.
But thanks for the history.
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