Abstract: Claimed embodiments of the integral nuclear reactor relate to nuclear technology and can be used in reactors with different types of heat transfer fluids with a high boiling point, such as, for example, liquid metals, molten salts, etc. Design features of the invention embodiments claimed which have a coil heat exchanger sectioned along the secondary heat carrier circuit provides for an improvement in technical and economic features due to a decrease in metal consumption of the reactor; efficient use of the internal volume of the reactor; improved safety in case of the heat exchanger tube leaks; enabling the removal of residual heat during the time after removal of the protective plug before fuel discharge operations.

Abstract: This invention relates to nuclear power engineering and may be used in power plants with liquid metal lead containing coolants, particularly in fast neutron reactors. The invention helps improve the safety of nuclear power plants.

Abstract: The method and system for control of oxygen concentration in the coolant of a reactor plant including a reactor, coolant in the reactor, gas system, mass-exchange apparatus, disperser and an oxygen sensor in the coolant have been disclosed. The method includes the following steps implemented by the system: estimation of the oxygen concentration; comparison of the oxygen concentration with the permissible value; if the oxygen concentration is reduced, comparison of the reduction value and\or rate with the corresponding threshold value; if the reduction value and\or rate of oxygen concentration is below the threshold value, activation of the mass-exchange apparatus; if the reduction value and/or rate of oxygen concentration is above the corresponding threshold value, supply of oxygen-containing gas from the gas system to the near-coolant space and/or activation of the disperser.

Abstract: A nuclear reactor comprising a housing having disposed therein an active region that contains a bundle of rod-type fuel elements enclosed in a tubular shell and submerged in a primary coolant that circulates between the active region and at least one heat exchanger. In order to reduce the level of pressure of gaseous fission fragments accumulating below the fuel element shell and to enable the most uniform possible distribution of the velocity field of the primary coolant at the inlet to the active part of the fuel elements, said fuel elements are provided in their upper parts with active portions, which are filled with fuel, and hollow working portions, which are situated below said active portions.