Saturday, September 1, 2018

A Generation IV Nuclear Reactor

Our current nuclear reactors are 50 years old and face retirement or expensive outlays to extend their lives. Moreover, they also have the capability of going critical, emitting radiation to the population and atmosphere if damaged or sabotaged. Since nuclear energy is the cleanest and represents about all electrical power produced, we have a cuirent problem..
There are many reactor concepts and these are classified as Generation IV nuclear reactors. However, all have serious problems,  delaying their construction. Estimation, at present, is that these reactors will not be on stream until the 2020s. Yet if these problems are resolved, there are many benefits. The reactors are light weight and meant to be transportable on flat beds to remote places such as bogs or other areas contaminated with organic waste  preventing public usage or usage for water or carbonaceous recovery or  as power plants to satisfy electrical requirments of small cities or factories.These reactors are cooled by liquid salts and can operate at temperatures ranging from 500 to 1000 C. Therein lies the problem because the molten salt is corrosive, especially when creating radioactive energy; and corrosion increases as the temperature increases.However. the higher the temperature the greater the efficiency, translating to lower cost, rendering the electreicity produced from the nuclear energy .competitive with traditional carbonaceous fuels.
One of the problems that require resolution before the reactors enter service is materials. Traditionally these have been steels. However as the temperature increases, accompanied with corrosion from radiation produxcts and temperature, newer more corrosion resistant steel are required.If operated at 1000C, the material selection becomes more difficult, because of the active molten salt and the radiation products created under the operating conditions.
One of the reactors considered was used to power submarines by the Soviet Union in the late 1990s. it was a reactor that used a lead-bismuth salt for cooling the nuclear fuel contained within the bed. This reactor has the advantage of operating at 500C, the low end of the reactor types competing to serve the market.  however the efficiency is not touted to be as good , rendering it more difficult to compete with traditional fuels.However, the material problem is more managable.because of the lower operating temperature. However corrosion still remains as the problem because of the activated corrosive salt serving as coolant. Therefore what is needed is something rto prevent the coolant from corroding the surface of the material of choice. There are many materials that can serve as coatings for corrosive protection.. These are generally sprayed onto the surface. Unfortunately at the surface an interface occurs because of the diffence between the coating deposited and the base alloy. This results because the alloys used for coating are brittle or may contain pores or debris that can result in crack formation rendering the coating to provide a path to the alloy.thereby not protecting it from corrosion. magnaTech has an idea which uses an activated atomic deposit on the surface to react with alloying elements within the steel to form stable intermetallic compounds that do not corrode and furthermore forming no interface that is brittle or defective but blends dirrectly to the traditional microstructure of the steel. If you have a severe corrosion occuring in your application, MagnaTech may have the solution improving performamce and ilowering cost and reducing contamination of the atmosphere.