SAFETY EVALUATION OF THE PROCESS OF DISPOSAL OF LITHIUM CONTAINING WASTE

N.P. Starovoitov, V.A. Dudkin, V.A. Kazakov, S.V. Korenev, P. V. Kozlov

This paper discusses the issues of ensuring the explosion safety of the recycling process associated with factors leading to excessive gas release. In the course of the experiments, gas evolution was determined during the dissolution of lithium. The influence of concentrations of Li+, OH- ions, lithium temperature on the rate of interaction of metallic lithium with water under normal conditions is shown. Experimental dynamic data on changes in the specific volume and rate of gas release during the dissolution of lithium in an alkali solution with concentrations of 30 g/dm3, 15 g/dm3 and distilled water as a function of the process time have been obtained.

INSTRUMENTAL MEASUREMENTS FOR THE PURPOSE OF TESTING THE METHOD OF RESTORING THE SPECTRA OF NEUTRON FLUXES AT WORKPLACES AND PLACES OF TEMPORARY STAY IN THE RADIOACTIVE WASTES LANDFILL

А. V. Vasiliev, А. А. Ekidin, M. D. Pyshkina, D. D. Desyatov, S. A. Chugunov

Energy distribution studies of neutron radiation at workplaces and places of temporary stay in the radioactive waste storage facility (RWSF) have been carried out. Based on dose rate measurements of the neutron and gamma radiation, a cartogram of the dose rate field of neutron and gamma radiation in the storage capacity of neutron sources in the RWSF has been constructed. The estimation of the conditionally true value of the ambient dose equivalent rate and the fluence was performed. Based on the obtained data on the energy
distribution of the neutron radiation flux density, the conditionally true values of the ambient dose equivalent H*(10), the individual dose equivalent Hp(10) and the integral neutron radiation flux density were determined both from the storage capacity of neutron sources in
RWSF and from the Am-Be source.

COMPARATIVE ANALYSIS CLASSICAL KINETICS OF A NUCLEAR REACTOR AND KINETICS OF A MARKOV CHAIN FISSION REACTION

N. N. Oshkanov, Ya. O. Komarova, P. A. Mikhaylova

The purpose of the study was to establish the limits of applicability of classical nuclear reactor kinetics, which is an approximation. The representation of the nuclear chain reaction in the form of a Markov chain made it possible to use it for the development of nuclear
reactor kinetics. The equations of this kinetics composed and solved have no approximations, which made it possible to accept it as the basic one for determining the applicability limits of classical kinetics for any duration of the chain reaction. The limits of applicability of classical kinetics have been determined. They are absent for a reactivity of 0.05β. For a reactivity of 0.05β-0.15β, the limits are 2.4-0.66 s of chain reaction duration for a deviation of 1% from the basic kinetics. For a deviation of 5% they are 11-3.7 s, for a deviation of 10% they are 30-7.7 s. For a reactivity of 0.15β-0.3β the limits are 0.66-0.28 s for a deviation of 1%. For deviation 5% they are equal to 3.7-1.5 s, for deviation 10% they are equal to 7.7-3.1 s. The boundary of the input reactivity of 0.05β, below which it is possible to apply the method of separation of variables in classical kinetics to derive the basic equations of point reactor kinetics, has been established. In addition, the main reasons for approximate equations and their solutions in classical kinetics have been established.

INTERNATIONAL VALIDATION OF THE SELECTIVE DETERMINATION METHOD OF AEROSOL FORM AND GASEOUS COMPOUNDS OF RADIOACTIVE IODINE IN WWR-CM

А. А. Ekidin, А. V. Vasilyev, I. I. Sadikov, S. A. Baitelesov, F. R. Kungurov, D. D. Todzhiboev, Sh. A. Alikulov

The results of a selective assessment of the activity of aerosol form and gaseous iodine isotopes compounds in the ventilation system of the research nuclear reactor WWR CM are presented. The measurement method used is widely applied in nuclear power plants, research and industrial reactor installations in Russia. The international validation of the justification of the choice of the algorithm, means and methods of selection of the gas-air environment, methods of measuring counting samples and data processing is aimed at increasing international confidence in the safety of both applied nuclear technologies and the results of radiation exposure control. The performed experimental studies have confirmed the high efficiency of purification (at least 99.9%) of radioactive emissions of the research nuclear reactor WW-CM from aerosols 131I. Radioactive iodine compounds removed into the atmosphere are represented by ¾ difficult-to-sort organic compounds, and ¼ by easily sortable molecular iodine.

WEIGHTED WATER QUALITY INDEX IN ENVIRONMENTAL MONITORING OF A MINING ENTERPRISE INFLUENCE ZONE

A. N. Medvedev, M. A. Medvedev

The article is devoted to the issues of adaptation and testing the weighted water quality index WQI to use in the environmental monitoring of a mining enterprise influence zone. WQI is widely known in the world and is a promising tool for use in the assessment of
natural water quality for timely informing the public and interested organizations about water bodies pollution. To adapt the WQI index, it is proposed to determine the weights of individual pollution indicators in accordance with the hazard classes of substances for
humans and the environment established in the Russian Federation. It is also proposed to use the Russian values of maximum permissible concentrations as standard values. The testing of the adapted index was conducted using the data of water quality observations in the river located in the influence zone of a mining enterprise for a three-year period (2017 – 2019). It showed that the WQI can be used as a relative characteristic of water pollution to compare the results of expeditionary surveys for different testing points within one year. It can also be used to assess the dynamics of water pollution in the same site in different years. The data obtained are consistent with the conclusions of the yearbooks of Roshydromet “Quality of surface waters of the Russian Federation” for 2017–2019. To use the adapted WQI as an absolute measure of water quality, it is needed to conduct additional studies to develop an appropriate classification.