Atoms for power; Pressurized water reactor

Was the law of the. Program produced by Purdue University under a grant from the Educational Television and Radio Center in cooperation with the National Association of educational broadcasters. On today's program written and produced by Bob McMahon. We'll pay a visit to the pressurized water reactor was. God. Willing. This is the man speaking. I'm in shipping port Pennsylvania where history is being made today. A small town on the Ohio River 25 miles northwest of Pittsburgh. History is being made on this spot because it's here we will find what is to be the first large scale atomic power reactor

in the United States. Here we find our nation's first full scale nuclear power plant. This power plant is being built on this spot today because we know that nuclear power is no dream of a distant future. It is a reality of our times. Already we've generated carbon here on the banks of the Ohio River just a few months from now the first reactor of any considerable size will begin to operate. It has a name. The pressurized water reactor most of the time it's referred to just as p w r. We like to tell you something of what it's like to design and build an atomic reactor that is going to turn out at least sixty thousand kilowatts of electric power. But first of all we'd probably better tell you how it all happened. The pressurized water reactor is the largest power reactor under construction in the five year reactor development program sponsored by the United States Atomic Energy Commission. The program for power a chipping thought has developed into a partnership between the

Atomic Energy Commission on the part of the government and the Duquesne Light Company on the part of private industry. The shipping port nuclear power station as designed to operate as an temporal part of the Duquesne Light Company system which serves a major part of Allegheny and Beaver counties here in Pennsylvania all of which might be considered to be a part of the Pittsburgh area. It is being built primarily to find out how a large scale power reactor will operate to provide data and experience for the further advancement and development of nuclear power the electricity it produces will be no different from that which you are using today in such great quantities in your home. Once the steam that is generated from the heat of an atomic furnace passed through the generator of the electric plant the effect is the same as it would be from any other source of heat electricity from one up Tomic reactor is certainly no different than that from any other source. Just as the Duquesne Light Company is furnishing the site for the entire project and will build

maintain and operate the new turban generator plant as well as provide operation and maintenance for the plants. Nuclear portions. The Westinghouse Corporation has been selected as a prime contractor to the Atomic Energy Commission for its design and installation. We've asked Mr. J.C. wrangled manager of the free wor project of the Westinghouse Electric Corporation to tell us something of the design and status of a shipping port plant. Perhaps First of all Mr. wrangled would take a little time out to explain to us some of the fundamentals of atomic power. I'd be glad to. The general concepts of nuclear power are easy to comprehend of course the engineering and design of an atomic power plant is complex but the broad fundamentals that you need to put things in proper perspective are quite simple. First of all there is the atomic reactor. Water circulates through the reactor. The combination of water and uranium in proper relationship produces a sustained chain reaction.

The neutrons released from one facia produce additional patients. These stations produce heat. The heat produced is proportional to the number of atoms but perception simply producing heat in the reactor will be no assurance that useful energy is being generated to accomplish this. It is necessary to add equipment to remove heat from the reactor. First we had a pipe and a pump. The pipe contains water. The pump provides the driving force to move water through the reactor. The water enters the reactor and is heated by the energy released by the uranium patients. This water called the primary coolant is contained in a closed cycle that is to say the same water circulates continuously through the system. Of course the water leaves the reactor at a higher temperature than that at which it enters. If nothing else were added to the plant this water would get hotter and hotter and still the plant would

produce mill usable energy. So we had another piece of equipment. A steam generator to remove usable energy. The steam generator in principle is nothing more than a pot surrounding a pipe. Primary could from the reactor blows through the bight secondary coolant water surrounds the by absorbing heat from the primary cooling it heats up and vaporize into saturated steam. The steam flows out through another BYB into a turban. This is the basic cycle of an atomic power plant. This is the new part the part that replaces the boiler in the conventional power plant after the steam leaves the steam generator it enters the turban which it rotates causing the electric generator to rotate in transforming heat energy into electrical energy. Mr. Rangle How does the pressurized light water reactor differ from say a heavy water ice sodium graphite reactor. Any other of the

400 or more possible types. Well let's go back to what happens when the uranium atom patients and then we'll be able gradually to work toward pressurized water as a particular means of controlling it and utilizing a chain reaction. When the uranium 235 that inflation's more than two neutrons from inside the fissioning atom itself are released these are the triggers which cause a chain reaction to be self-sustaining. They strike other uranium 235 atoms and cause them to fail. In some types of reactors when the neutron is released by fission it strikes another uranium atom without striking anything else which would cause it to give up some of its energy and thus slow down if the neutron were to strike something else. It would give up some of its energy just as one billiard ball hitting another would give up its energy to the second ball. A new turn would hit something and his slowdown is called a slow or thermal neutron

thermal neutrons are more efficient in causing uranium 235 atoms to split the BWR reactor makes use of this principle. It is a thermal reactor material which slows down the neutrons is called a moderator. The PDB our reactor uses like water as a moderator and the same light water as the primary cooling in its function as a coolant the water goes through the reactor core and absorbs part of the heat generated at the same time it is performing its task as a moderator and slowing down the new terms therefore causing atoms of uranium to fission more easily. What is the reactor vessel itself where all this activity you've been describing takes place. What is it going to look like. It's quite large from top to bottom and measures 33 feet. The inside diameter is approximately nine feet.

The walls are eight inches thick and are made of ordinary steel clad with one quarter inch of stainless steel. The water enters at the lower end flows upward through the core and goes out the top. Inside the pressure vessel the nuclear core is housed. This is an assembly of plates and rods arranged in the general shape of a cylinder six feet high and six feet in diameter. Inside the blades and runs is the uranium the patients the uranium 235 patients and heats the fuel elements which in turn heat the water. How do you start and stop the chain reaction whenever it becomes necessary or how do you slow it down if you wish. For this we have rides that move in and out to start stop and control the level of the chain reaction. These rides absorb neutrons preventing them from causing other atoms to splat and thereby re reducing the number of patients per second. Not all reactor designs need these control

rods to start limit or stop the chain reaction. Since BWR is a thermal reactor and since solid fuel elements are employed in the reactor instead of say uranium in a liquid state we have to use these control rods. Well thank you very much Mr wrangle for your very clear and concise description of atomic power and the pressurized water reactor. Up to now perhaps we made the design construction and operation of an atomic part plant sound too easy. We certainly don't want to leave you with the impression that it is all as simple as that. Here is Mr PGD hot assistant P.W. our project manager for the Westinghouse Electric Corporation. Mr. Duff What are some of the basic problems of reactor design. There are a number of things involved and probably the first of the fundamental problems involves the very speed at which we are making new scientific discoveries in the field of reactor development. They are coming so fast that although we do our best

it is difficult to keep up with them. There are very few handbooks containing data for building reactors. Almost everything we do is brand new. Often we must first of all spend great amounts of time and millions of dollars building working models to give us the information we need in regard to various applications of nuclear physics. Then there are many thermal and hydraulic problems for which surprisingly little information is available. One is how to determine the maximum amount of heat which can be transferred from the uranium fuel elements to the water without knowing the fuel elements. We have to build models to test this. Most of the time we use electricity instead of an actual Chain Reaction to create the heat we use to perform these tasks. There are problems of material many new materials such as zirconium and Hafnium for example which we previously knew next to nothing about have the basic nuclear properties to perform certain tasks in an operating reactor. We have to learn how to work with these metals. This takes great amounts of time and

extensive testing and very often before we use them we have to develop ways of manufacturing them in sufficient quantities and at a reasonable cost so that they can be used. Many materials in a reactor plant must withstand very high radiation without sustaining damaging changes in their structure or dimension. In the process of their use in the reactor they become highly radioactive and cannot be handled except by remote control. And with the use of adequate shielding sometimes through the use of remote manipulators through four foot thick concrete walls with equally thick lead glass windows to protect workers from the effects of radiation another materials problem is that of corrosion resistance are the primary system water is extremely corrosive to ordinary material and only minimal amounts of corrosion can be tolerated. Let's take an example and consider for a few moments a pump in an atomic power plant. The water in the pipe and in fact water throughout the primary system is radioactive to some degree. We must therefore

prevent leakage out of the system. We do this by using a canned pump that's the water which contains the radioactive particles cannot escape. It is hermetically sealed. The water however is hot corrosive and is not a lubricant. There have been many problems in making bearings which would run at high speeds and be satisfactory in operation of the pump without normal lubrication. Bear in mind also that the water in the pump is under 2000 pounds per square inch pressure. This means that hot water under high pressure is inside the electric motor so you can see that evaluation of new materials. Radiation Effects and corrosion resistance are all basic to reactor design. Whether a material or piece of equipment is new or old it must be surveyed in a new light. This imposes a heavy development load the newness of the field will be overcome with time and the engineering will catch up with science in its application. However until this happens advances in reactor technology are going to

require expensive investments in the tools of research. Perhaps the most difficult problem facing a reactor physicists today is that a reactor lifetime. How long will the reactor run before the chain reaction stops the reactor core itself. Is the expendable material in the BW our plant. It corresponds to the coal or oil in the conventional power plant. The longer a reactor core lasts the cheaper the unit cost of energy obtained from this car will be the lifetime of the reactor core can be limited by a number of things other than the stopping of the chain reaction. It can be limited by a mechanical and materials problems such as corrosion or mechanical deprivation resulting from intense and prolonged radiation. Either of these can make it necessary to replace the reactor core. But what we want to consider next is only the question of maintaining the chain reaction. The chain reaction is ultimately stopped in a reactor because of two things. First the fissionable fuel material is depleted and second the products formed in the

fission process. The halves of the split atom generally poison the reactor and ultimately choke off the chain reaction. The fissionable material the nuclear fuel which we start with and the people are is you 235. This is the rare isotope of uranium which occurs in the proportion of one part in one hundred forty. In normal or natural uranium the remainder of the uranium is the isotope you 238 the U 238 is not itself a fuel but is what we call a fertile material. It can be converted in a reactor to plutonium which is a nuclear fuel. Thus we have the possibility in our of making new fissionable material or nuclear fuel as we use up the original fuel on the average in the PDV are we expect to make 8 atoms of plutonium for every 10 atoms of uranium 235 which are fission from a lifetime and from a cost point of view the most desirable state of affairs would be to make the new

nuclear fuel in the reactor and then to burn it in place. This we can do in part just how far we can go today is quite uncertain. The other large uncertainty in Reactor life time is the effect of the fission products. The split halves of the uranium atoms which gradually poison the reactor and shut off the chain reaction. The degree of this poisoning is not all well known today particularly for those fission products which do not have a spectacular poisoning effect but gradually accumulate and choke off the chain reaction. This lifetime problem and the uncertainties that surround it are not peculiar to the PTB are that are coming to power reactors in general. This problem is without doubt the most difficult one in the power reactor field today. A final point in the nuclear fuel cost is the recoverable material in the reactor at the end of its life even after the poisons in the reactor accumulate to a degree after which a chain reaction will no longer sustain itself.

There is still in the reactor a substantial amount of fuel both uranium and plutonium. This fuel can be reclaimed by a chemical reprocessing of the reactor core. If the cost of the chemical reprocessing is reasonable the recovery process can lead to a reduction of nuclear fuel costs. Although we can make no statements today in this area it is expected that appropriate techniques with reasonable cost will be available by the time large scale reprocessing is required. The best statement we can make today is that we will have to build and operate power reactors before we have the necessary information on which to estimate nuclear power costs with reasonable accuracy and the P.W. our zirconium is the material used to cover the fuel and certain other parts of the reactor core. There Conium has two very valuable properties that make it an excellent core structure of material that has very low at her parents where the fashioning process and it has

good corrosion resistance and hot water at 600 to 700 degrees Fahrenheit. And possesses adequate strength at these temperatures. However it has one very serious disadvantage. It is very costly. Development costs on zirconium have actually run into millions of dollars. What is needed now is a revolution in the technology a making zirconium a contribution similar to that of Charles Hall in the aluminum industry at the end of the century making cheaper zirconium is not the only way to get less expensive reactor materials. It has been estimated that if a material such as an aluminum alloy could be used in place of zirconium 80 percent of this cost might be saved. So far no aluminum alloy has shown resistance to hot water which is at all comparable to zirconium for the temperatures encountered in the PDV are. But this is a very significant item and one well worth a great deal of developmental effort. Another expensive material is the Hafnium used for control rods. To be satisfactory for this purpose

a material must be capable of absorbing neutrons. That is its function is to slow down and stop the chain reaction in the reactor. It must also have good corrosion resistance maintain constant dimensions under operating conditions and have mechanical strength under nuclear bombardment. It so happens that Hafnium is a very good material for this purpose but it is rare and produced as a part of the zirconium process. Unfortunately not enough has name is produced by these means to satisfy the industry and the cost is high. Problems such as these are many. Some of them will be able to experience others to development and hard work but some must be conquered by the big step. The new idea or approach the road to cheaper courses well be found but the development costs in both dollars and manpower remain high. Once again name we must come to the realization that the final answer to so many of these important questions and problems of reactor design must come in the future in the

future to realize the time when electric power will be as cheaply produced from an atomic source as we can produce it today by more conventional means. But for some more information on this subject Let's bring Mr. Rangle back to the microphone. Most studies indicate that the capital investment for atomic power plants for some time to come is likely to be higher than investments for fossil fuel plants. The great hope for lower power cost from nuclear plants lies in the potential savings resulting from the use of the fissionable material such as uranium is a fuel atomic power plants are costly to build today for a number of reasons. One of them has to do with the design of the plant itself. In conventional power plants 75 years of design experience has produced a wealth of experience upon which the designer has to depend. However the designer of an atomic power plant has no such experience to draw on. He can only guess

and as a result it is not possible today to design an atomic power plant that is as economical as plants of the future will be. Another reason is that a large percentage of reactor plant cost is made up of the cost of companies that today must be specially designed to very exacting specifications. One of the basic reasons for these special designs is the fact that complements must be leak proof to prevent the release of radioactive water from the primary plant. It is especially important to prevent leaks. If the water activity has been increased by phasing products which have escaped from the reactor core therefore we have had to develop leakproof pumps valves and other types of moving mechanisms that will operate in the water of the reactor plant pumps for example may cost 50 percent more than what a conventional pump of comparable

rating would cost. Leak proof valve developed for the plant cost as much as three times what would be paid for a conventional valve which would be expected to leak a small amount in the future we will find ways to reduce the cost of these compounds. In addition as more plants are built quantity production will help reduce the price. After a reactor core has reached the end of its useful life it must be replaced the old car is highly radioactive and must be heavily shielded at all times. In addition it must be continuously cooled since it continues to produce some heat even after it is removed from the reactor vessel. The facilities required to remove and handle the PDB our reactor core consist of a water failed canal forty three feet deep 22 feet wide and 110 feet long. A large building covering the canal and a one hundred

twenty five ton crane experience in handling spent cores will be gain from this facility. The cost of the reactor plant is increased by the fact that we must because of our present lack of knowledge build it as stainless steel. Less expensive steel is used in conventional power plants because chemicals are added to the water to keep it from attacking the steel. However in reactor plants these chemicals are damaged by nuclear radiation as they circulate through the reactor. A very extensive experimental program is underway to find out how to build this type of reactor plant of lower cost steel. However for this plant stainless steel must be used at a cost penalty of at least 10 percent of the reactor plant cost. Reactor plant designers for many years to come will be ultra conservative in the design of all plant features that in any way affect safety. In the case of

BWR We are taking all necessary precautions to prevent the release of radioactive materials from the plant. We believe that such precautions will produce a plant which is perfectly safe. However to be doubly safe we are also sealing the plant inside four interconnected steel containers capable of going to containing any radioactive steam or water that might be released. It's inconceivable accident did happen. This design approach will produce a plant which is extremely safe but very expensive to build. As we learn more about reactor plants we will probably find ways of eliminating these expensive containers. However more plants must be built and operated before we will be sure that we have arrived at this point. These are just a few of the many problems to be solved before all possible cost reductions can be made. And for these reasons reactor plans are much more expensive to build

now than they will be in the future. The best way of obtaining the necessary experience and of solving these problems is through the construction and operation of more reactor plants. Thank you Mr wrangle. I think we have a very good idea by now of the work that has to be done before we have the necessary answers to all the problems that are so prevalent in the field of atomic power. Therefore these problems can be solved there is one major problem that stands out above all the rest and that is the problem of finding the manpower itself to do the job. Today both industry and government are becoming increasingly handicapped because of a lack of trained scientific and technical personnel in every line of atomic work. This lack of manpower or brainpower if you prefer can have very far reaching consequences for our nation. If we do not wake up soon and begin to take steps to alleviate our growing scarcity of trained scientific and technical personnel. Our

chief power rival Soviet Russia will one day surpass us in the important field of the atom or at the present time. But let's let Admiral a straw's chairman of the Atomic Energy Commission tell us Russia appears to be training the scientists and engineers. At a considerably faster rate than we. Missed Alan Doss the distinguished director of our Central Intelligence Agency has publicly stated. That between 1950 and 1960. Soviet Russia will have graduated. One million two hundred thousand scientists and engineers compared with about. 100000 here in the United States present program. Those figures would not be so important. If it were not for the fact that we believe that our own colleges and engineer and universities are turning out only about half the number of engineers. That we require.

Obviously a mass corrected. The third situation in a few years. Well become a national calamity. Imperiling our security and freedom. In an age of expanding dependence upon science and technology. This is a most serious subject. That demands proper consideration. And far more emphasis than I am able to give it in this. Shot John report. Well that's our story for today and atoms for power. The story of our nation's first full scale large size atomic power plant is scheduled to go into operation in late 1057. I thanks go to the management and personnel of the Canaanite company in the Westinghouse Electric Corporation for their help and cooperation in bringing this program to. Atoms for power was written and produced by Bob McMahon for radio station WBA

at Purdue University under a grant from the Educational Television and Radio Center a technical adviser to the program was Professor Donald J tend them up the Purdue Department of Physics. You're not writers where Walt Richter and Jim host and and this is John Vance always be speaking. Atoms for power is distributed by the National Association of educational broadcasters This is the Radio Network.