Dry containment

Moscow State University of Civil Engineering, 26, Yaroslavskoye shosse, Moscow, 129337, Russia

¹ Corresponding author: PergamenchikBK@mgsu.ru

Abstract

The dry containment (DC) is a metal cylindrical vessel (tank) 0.6 m thick, 5 m high, which is filled with serpentine concrete and surrounds the reactor vessel. DC reduces the radiation flux to the conventional concrete of the biological shield of the PWR reactor. Generates, due to the high content of hydrogen atoms in serpentine rock, a radiation spectrum with an increased content of thermal neutrons, which is important for the operation of the ionization chambers of the reactor power control system. Traditionally, the DC is dried after concreting the metal structure at a temperature of up to 2500 °C to remove water from the concrete that is not chemically bound during the hardening process. The drying operation is not fixed by the standard instruction, it is solved according to various schemes and is associated with a long preparatory period, significant labor and financial costs. There is no evidence of the need for drying. In the present paper, based on the analysis of the DC solution, a number of projects of works on its construction, existing instructions, the conclusion is made about the possibility and expediency of refusal from drying of DC and accompanying operations on quality control with the use of radioisotope sources. The corresponding cost savings are estimated at more than 100 million rubles for the power unit.