Patent Number: 047553529
Section: summary

The present invention relates to a system of generating electricity by the use of a swimming pool type nuclear reactor. In particular, the invention is directed to an electricity generating system using a swimming pool type reactor which employs a forced circulation of the coolant-moderator by a pump in order to raise the operating temperature of a turbine-generator fluid. BACKGROUND OF THE INVENTION The swimming pool type nuclear reactors are well known and their uses for the purpose of producing heat have been widely proposed. IEEE Spectrum, February 1984 pp. 50-55 describes various proposals of the use of low temperature nuclear reactors for space heating. Most of the reactors described in the above article use closed circuit moderator-coolant flows which are pressurized throughout. The Canadian Slowpoke reactor which is also mentioned in the article is open circuited in that it has a pool of light water under atmospheric pressure as a part of the circuit. The present inventor co-authored a paper presented at the technical committee meeting and workshop of International Atomic Energy Agency held at Krakow, Poland on Dec. 5-9. 1983. The paper describes the prototype 2MWt Slowpoke-3 heating reactor concept. The present inventor also presented an article "Nuclear electricity from a low-temperature organic Rankine cycle engine" at the 1984 Annual Conference of the Canadian Society for Mechanical Engineering, Halifax, Nova Scotia, May 23-25, 1984. It was proposed there that a pumped Slowpoke reactor results in a higher mean temperature supplied to the Rankine engine. An intermediate water loop is used in both circuits to avoid any Freon [Trademark] entering the reactor pool. U.S. Pat. No. 3,308,032, Mar. 7, 1967 (Berthod) teaches swimming pool type reactors in which an independent cooling water circulation system is set up within the body of the swimming pool water to limit surface radioactivity from nitrogen 16. By the use of suitable guides and/or pressure distribution arrangements e.g. baffles etc in the pool, independent cooling water circulation system which includes a pump will ensure that the cooling water will flow according to a definite pattern in one direction or the other through the core and the body of the pool water. The patent fails to concern itself with increasing the mean temperature of the coolant-moderator or mention electricity generation with its associated problems. U.S. Pat. No. 3,769,789, Nov. 6, 1973 (Niggermann) discloses a power conversion system employing a Rankine cycle engine wherein an organic fluid such as toluene is used as the working medium. The system uses gas combustion at a temperature of about 3000.degree. F. which heats the toluene to produce superheated vapour of about 700.degree. F. The superheated vapour drives a turbine to produce electricity. OBJECT OF THE INVENTION It is an object of the present invention to provide a thermodynamic system which converts heat energy produced in a nuclear reactor to electricity. It is another object of the present invention to provide a thermodynamic system which converts heat energy produced by a swimming pool type nuclear reactor to electricity. It is a further object of the present invention to provide a thermodynamic system wherein a swimming pool type nuclear reactor is used for producing heat and an organic Rankine cycle engine is used for converting the heat to electricity. SUMMARY OF THE INVENTION Briefly stated, the present invention makes use of an organic fluid having a low boiling temperature contained in a Rankine cycle engine in order to take advantages of inherently safe swimming pool type nuclear reactors and thereby convert heat to electricity. According to the present invention, a thermodynamic system for converting heat produced by a swimming pool type reactor to a more useful form of energy includes a pool containing light water functioning as the moderator-coolant-shielding for the reactor and being open to the atmospheric pressure. The system further includes moderator-coolant passage means and a nuclear reactor core in the passage means. The passage means has an intake end and a discharge end and defines a flow of the moderator-coolant between the ends, both of which are positioned in the pool. Pump means are provided in the passage means at near the intake end and draws the light water from the pool and circulates it under pressure through the passage means and back to the pool by the discharge end. The system is equipped with a primary heat exchanger in the passage means between the core and the discharge end to transfer heat energy of the light water to a heat exchanger fluid contained in a secondary circuit. Boiler means are provided in the secondary circuit to heat an organic fluid contained in a turbine circuit which includes turbine means to be driven by the heated organic fluid to drive an electric generator.