Brunswick Nuclear Power Plant Infrastructure, Research Paper Example

Located in Brunswick County of North Carolina, the nuclear power plant called Brunswick is operating to provide a virtually limitless supply of energy to its surrounding areas. The Brunswick Nuclear Power Plant was first commissioned back in 1975 by the Duke Energy Progress where they currently maintain 82% ownership. The remaining 18% of ownership is claimed by the North Carolina Eastern Municipal Power Agency. However, despite already being a majority shareholder, Duke Energy Progress is presently running negotiations about buying the remaining 18% from the North Carolina Eastern Municipal Power Agency.

The nuclear power plant currently operates on two units which run on 990 megawatts (MW). These units are labeled as general electric boiling water reactors. These reactors are cooled off by the water which flows from the Cape Fear River, where it is then released into the Atlantic Ocean. The reactors are equipped with a filter system that screens out any fish or marine life that may get caught in the water cooling system. This is the reason for the Brunswick Nuclear Power Plant’s geographic location as it is easily accessible to the waters of the Atlantic Ocean off the coast of North Carolina.

Back in 2011, the Brunswick Nuclear Power Plant was the cause of a declared emergency due to a nuclear leak. The situation was serious enough to the point that the Federal Bureau of Investigation (FBI) was forced to investigate the events that may have been the cause for the nuclear reactor leak at Brunswick. It was on November 16 of that year that the emergency was declared because of the leak at the Brunswick nuclear plant. The Nuclear plant had been undergoing a process of maintenance at the time. The Brunswick nuclear reactors had dropped to 7% of their power while the sleek continued to deteriorate. The operators working at the Brunswick Nuclear Power Plant decided that they should manually shut down the nuclear reactors completely to avoid a nuclear disaster. Unfortunately, the manual shutting down of any nuclear reactor in the event of a panic can be extremely dangerous. It was later discovered that the reason behind what caused the reactor to malfunction in the first place was because the reactor pressure vessels or (RPV) were not fully pressurized. The media conveyed to the general public that this malfunction was simply a result of incompetence on the operators’ part due to failures in quality control, policy control, standard procedures, and testing. The Nuclear Regulatory Commission or (NRC) had sent out a special investigative team to investigate how or why these nuclear reactors at Brunswick leaked nuclear radiation.

They found that radioactive water was leaking from the top of the vessels of the nuclear reactors. It is foreseeable that something like this may occur at a nuclear power plant such a Brunswick with it consisting of boiling water reactors. This was a significant finding because the boiling water travels directly through the reactor core. This is similar to the Fukushima Nuclear Power Plant in Japan which is also a Mark 1 boiling water reactor. This means that any releases of water from these types of nuclear reactors means that it is highly radioactive.

What the operators at Brunswick needed to do to determine exactly what the source of this problem was, was take the entire reactor vessel apart which is referred to as a required reactor vessel disassembly. While this disassembly of the reactor vessels was being conducted, the operators found that the reactor vessel head had not been installed properly; leading to the un-tensioned RPVs.

In an academic research journal on the Brunswick Nuclear Plant, it was noted that new mitigations and strategies for monitoring the reactors were integrated into the operations plan. Nuclear reactors are necessary for the global economy to function. They can supply the global economy with a virtually limitless source of energy as nuclear reactors do not need to be refueled for twenty plus years. Nuclear energy or atomic energy is that energy which is obtained from nuclear reactions, i.e. from reactions of particles and atomic nuclei. These reactions can occur spontaneously or can be caused by the human being. This type of energy is very efficient, but there are risks that we need to know. (Williams, Varnam, and Morgan, 2015)

Nuclear energy is the energy that is obtained to manipulate the internal structure of atoms. It can be obtained through the division of the nucleus (nuclear fission) or the union of two atoms (nuclear fusion) as demonstrated at the Brunswick Power Plant. Nuclear energy is mainly used to produce general electric energy; this energy (that is obtained in the form of heat) is used to generate electricity in nuclear power plants, although there are many other applications of nuclear energy. Physics defines a nuclear reactor as an installation capable to initiate, maintain and monitor the reactions of fission chain that takes place in the reactor core, composed of the fuel, coolant, the control elements, structural materials and the moderator in the case of thermal nuclear reactors.

There are two ways to design a nuclear reactor, either by slowing (tempering) neutrons or fast increasing the proportion of fissile atoms. For the task of slowing down the neutrons are used a moderator (light water, heavy water and graphite) and the slow neutrons resulting are called thermal, so that the reactors based on this technique is known as thermal reactors, unlike those who employ fast neutrons (fast), called Fast Reactors. This is the detailed reasoning behind the necessary water source for the Brunswick reactors.

Physicist Patrick Huber notes in his academic journal on nuclear reactors that at the time of constructing any reactor, it is necessary to have a critical mass of fuel, that is, enough fissile material, in an optimum arrangement of the fuel and the rest of the core materials, to keep the chain-reaction. The layout of the absorbent of neutrons and the control rods allow you to maintain the criticality in operation and the process of shutdown and start up. The core is the part of the reactor where it produces and maintains the nuclear chain reaction. Its objective is to heat the water in the primary circuit. It is designed to operate in a safe and controlled manner, so as to maximize the amount of energy extracted from the fuel. Each component of the Brunswick reactor cores plays an important role in the generation of heat. (Huber 2011)

The fuel of a nuclear reactor is a material fission in such quantities as to reach the critical mass, and placed in such a way that it will be possible to extract rapid heat that occurs in its interior due to the nuclear chain reaction. Fuels used in the nuclear power plants like that of Brunswick are in solid form, although they vary from the ceramic uranium dioxide slightly enriched uranium in tubes, magnesium alloy dioxide until natural or enriched uranium in tubes of zirconium alloy, everything depends on the type of the reactor.

In general, a fuel element is made up of a provision of the quad of the fuel rods, although the provision of the Russian reactor hex of water-water energetic reactor or (VVER) pressurized water should be mentioned; meaning Vodyanoi Energetichesky Reaktor in Russian. Holding the guide tubes to the racks of fuel it will get the centers of the fuel rods and the guide tubes are the same distance. All the fuel elements have the same mechanical design. Some contain bundles of control rods contain poisons and other consumables or neutron sources.

To ensure the quality of fuel elements, there are numerous inspections and testing of both raw materials and the finished product that the Brunswick plant produces. Bundles of control rods provide a rapid means for the control of the nuclear reaction, allowing quick changes of power of the reactor and its eventual stop in case of emergency. They are manufactured with absorbent materials of neutrons (boron carbide or alloys of silver, indium and cadmium, among others) and generally have the same dimensions as the fuel elements. The reactivity of the core increases or decreases by raising or lowering the control rods, that is to say, by modifying the presence of neutron-absorbent material contained within them in the kernel.

For the Brunswick reactors to run for a period of time you have to have an excess of reactivity, which is maximum with the fresh fuel and with decreasing the life of the same until it is canceled, at which time the fuel is recharged.

In normal operation, the Brunswick Power Plant reactors have the control rods or partially removed from the core, but the design of nuclear power plants is such that in the event of a failure in your security system or reactor control, always acts in the sense of security of reactor introduced fully all the control rods into the core and bringing the reactors to safe stop in few seconds.

In nuclear reactions the variation of mass produces a large amount of energy at the rate of the equation E=mc².  To understand how this energy is necessary to know the concept of nuclear binding energy, the energy required to unbundle a nucleon (protons and neutrons that make up a nucleus).  ?E = ??m?c² ; where ?E is the nuclear binding energy, while ?m is the absolute value of the change in mass, expressed in kilograms for that energy is expressed in joules. The atoms are held together by the interaction of two major forces: the nuclear force, which holds together the nucleon and the electrical force, produced by the charge of the protons and it tends to separate them. When the core reaches radios over the electrical force destabilizes the atom to a greater extent.

This is the most frequent kind, with over 230 reactors for power development and in more than a hundred uses for propulsion of navy ships. These reactors use water as coolant. The design is unique in carrying on it a main cooling system that generate throughout the core to great pressure levels as well as a secondary cooling circuit where the evaporation is made to move the turbines for propulsion.

In a pressurized water reactor or (PWR) such as the Brunswick reactors, there are the so called fuel structures, which are not more than 200 or 300 bars, positioned vertical in the kernel, for informational purposes, a reactor considered as “large” will have some 150-250 structures with 80 -100 tons of uranium. This design saves great similarities with the PWR, except that there is a single circuit where the water is to a lower pressure (about 75 atmospheres) so that boils within the core to 285 °C.  The reactor has been designed to operate with the 12 to 15% of the water in the upper part of the core in the form of steam, thus taking less moderating effect and efficiency there. The frame of the BWR fuel comprises about 90-100 fuel rods, and there are reactors with up to 750 frames in the reactor core, with 140 tons of uranium.

The design of the Brunswick reactors uses natural uranium oxide (0.7 % U-235) as fuel, so a more efficient moderator is required, in this case the heavy water (D2O). With the Brunswick system, the moderator is enriched (e.g. water) instead of the fuel.

The moderator is in a big tank called Calandria, crossed by hundreds of pressure pipes that horizontal form channels for the fuel, cooled by a flow of heavy water to an enormous pressure within the primary cooling circuit, reaching 290 °C.  As in the Brunswick PWR, the primary coolant generates steam in a secondary circuit to move the turbines. The design of the pressure pipe allows the reactor would be refueled progressively without having to turn it off, isolating the individual pressure pipes of the cooling circuit. The frame of the Brunswick fuels consists of 37 bunches of 0.5 meters in length (uranium pellets in ceramic zircaloy tubes) plus a support structure, with 12 bunches resting stop to stop in a fuel channel.

These reactors are the 2^nd generation of European gas cooled reactor vessels. These reactors use a graphite-moderated with CO2 carbon dioxide as a refrigerant. The fuel are pills of uranium oxide (enriched to 2.5 -3.5 % ), contained in stainless steel tubes. The carbon dioxide flows throughout the core of the reactor up to 650 °C. It then goes through the tubes of steam generators, which are still inside of the pressure of steel and cement, but outside the core. The control rods go through the moderator as well as a secondary shut-off module which includes the injection of nitrogen based gasses to the coolant-gas.

The advanced gas-cooled reactor or (AGR) was created from what is referred to as the “Magnox” nuclear reactor, as well as the graphite-moderation and cooled down with CO2 and that use natural uranium as fuel, in metallic form. There are still some of these reactors operating in Great Britain. Adversely from the Brunswick design, this is a design from the Soviets, which was originally developed from the plutonium reactors. It employs long vertical pressure pipes (7 meters) that pass through the graphite-moderated, and is then cooled down by H2O, which boils within its core to a temperature of 290 °C, as BWR. The oxide is combustible of low-leveled uranium with bunches of 3 and a half meters long. With the moderation due in large part wth the graphite, the excess of boiling water eventually decreases the neutron absorption while avoiding the inhibition of a fission-reaction.

It is about getting trigger the process of nuclear fusion for a few nanoseconds by means of powerful lasers launched against some milligram of atoms of deuterium and tritium. This is the objective pursued by two gigantic centers of experimentation that are built in California (USA) and Bordeaux (France), the National Ignition Facility (NIF) and the Mega joule Laser (LMJ), respectively.

When both magnetic fields are generated by foreign wraps, is called a stellarator configuration. When it is just the toroidal magnetic field which is generated by the external magnets, and the poloidal is generated by the own electrical current that form the plasma in its path toroidal, the configuration is called Tokamak. In the case of the ITER, the configuration adopted is the Tokamak. This system has been developed mainly in the United States, Sweden and Germany.

As is in the Brunswick Plant, the heat generated by the chain reactions is used to boil water. The steam produced is entered into a turbine that drives an electric generator. The steam leaving the turbine passes through a condenser, where it is transformed back into liquid water. Subsequently returns to the reactor to be driven by a suitable pump.

In The Journal of Nuclear Materials by Oono, Ukai, Kondo, Hashitomi, and Kimura, water pressure is greatly emphasized in how it is integrated with BWR Mark 1 reactors such as Brunswick. The coolant is water under high pressure while the moderator may be water or graphite. Its fuel is also Uranium-238 enriched in uranium-235. The reactor is based on the principle that water subjected to great pressure can evaporate without reaching the boiling point, i.e. at temperatures greater than 100 °C.  The vapor is produced at 600 °C, which is passed to a heat exchanger where it is cooled and condensed back to liquid form in the reactor. In the exchange there is transfer of heat to a secondary circuit of water. Basically consists of the control rods and by diverse instrumentation monitoring. (Oono, Ukai, Kondo, Hashitomi, and Kimura, 2015)

Control rods are driven by a series of mechanical systems, electrical or electronic, in such a way as to ensure the rapid extinction of the nuclear reactions. The instrumentation for monitoring is located on the inside or outside of the reactor core and its purpose is to maintain constant surveillance of those parameters that are required for security: pressure, temperature, level of radiation, etc.

The nuclear contamination is a radioactive dust that is generated when a nuclear weapon explodes. This explosion destroys any material into a ball of fire; in the water, the minerals become radioactive due to neutrons from the core of the pump.

As written in the academic journal of discharged nuclear materials by Ibaraki Tokai, nuclear contamination is caused primarily by nuclear waste. This is the case with the incident at the Brunswick Power Plant and an even more severe case at the Fukushima plant in Japan following the 2011 tsunami. (Nagai, Chino, Terada, and Katanta, 2012)

Consequences of nuclear contamination can involve,

• human disease: cancer, malformations of the fetus,
• Deficiencies of the immune system, neurological kidney and liver.
• Deterioration of the flora and fauna
• profound changes in the atmosphere
• pollution of farmland and drinking water
• favors the development of pests and
• diseases transmitted by insects or animals
• food shortage

This is different from radioactive contamination which is not a primary type of contamination at the Brunswick Plant. Radioactive Contamination is produced mainly by the use of radioactive substances natural or artificial, the use of nuclear energy and invention of the atomic bomb is a great danger of contamination for nature and humanity; many remnants of the polluting materials that are used to carry out nuclear tests have been spread over the whole earth, as well as the waste that are also in the water that is used to cool the reactors. The most dangerous tests are conducted in the atmosphere and make the force produced by the explosion causes a significant increase in temperature and the production of gas and other products that are released into the atmosphere; then with the action of the wind and rain these are dragged into other places affecting the earth, when they fall to the ground, since crops and pollute the waters of the lakes, rivers, and seas.

Chemical pollution can occur with use of nuclear reactors such as the ones at Brunswick. This type of pollution is caused by the manufacture of electronic products that generate waste that cannot be treated as normal trash, because they contain substances hazardous to health and the environment. Examples of these substances are lead, mercury, cadmium, PVC, hexavalent chromium, and brominated flame retardants, among other toxic substances.

Nuclear Contamination is a serious problem, and a way to fix this is aware of the serious damage that the radiation cause on our planet; we have to find alternate means to replace the use of nuclear energy, as leakage in nuclear power plants are sincerely harmful, not only for humanity, but for the entire world.

While the Brunswick Nuclear Power Plant will always carry a high risk for contamination, it is necessary to maintain its operations until technology can provide a safer and more effective alternative to energy. Until that new source of energy is discovered, it will be necessary to operate the Brunswick Power Plant with extreme precautions so that there is not another nuclear spill as seen in 2011.

References

Williams, S., Varnam, J., & Morgan, D. (2015, May). Brunswick Nuclear Plant IGSCC Mitigation Strategy and Monitoring. In CORROSION 2015. NACE International.

Huber, P. (2011). Determination of antineutrino spectra from nuclear reactors.Physical Review C, 84(2), 024617.

Oono, N., Ukai, S., Kondo, S., Hashitomi, O., & Kimura, A. (2015). Irradiation effects in oxide dispersion strengthened (ODS) Ni-base alloys for Gen. IV nuclear reactors. Journal of Nuclear Materials.

Nagai, H., Chino, M., Terada, H., & Katata, G. (2012). Atmospheric dispersion simulations of radioactive materials discharged from the Fukushima Daiichi Nuclear Power Plant due to accident. Consideration of deposition process.