Development of Processing Technology for Radioactively Contaminated Water at Chernobyl Nuclear Power Plant - 19656

Conference · Mon Jul 01 00:00:00 EDT 2019

OSTI ID:23005471

Voinov, Igor; Remez, Victor ^[1]; Myasnikov, Alexey; Terzi, Analoly ^[2]

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1. METOIL s.r.o. (Czech Republic)
2. Chernobyl Nuclear Power Plant (Ukraine)

During the operation of the Chernobyl Nuclear Power Plant, distillation by evaporation was the main method for processing radioactively contaminated water. When the plant was decommissioned, the evaporation facility was mothballed and floor drain treatment was suspended in 2016. At present, the existing tanks with the capacity of 26,000 m{sup 3} are more than 60% full with radioactively contaminated floor drains, which requires alternative processing methods. The current process flow for radioactive waste management at State Specialized Enterprise 'Chernobyl NPP' includes processing of accumulated liquid radioactive wastes at a liquid radioactive wastes processing plant. Under the processing technology, liquid radioactive waste is immobilized at the plant by cementation and the resulting solid radioactive waste is then buried in a near-surface storage. Key factors for the selection of alternative radioactively contaminated water processing methods are the possibility to clear the processed water (no control monitoring), which requires the same degree of processing as for drinking water, and minimization of radioactive waste generation due to the lack of free space for solid waste disposal in the near-surface storage. Floor drains that require processing contain radionuclides such as {sup 137}Cs, {sup 90}Sr, {sup 60}Co and {sup 40}K. The current level of the total beta and gamma activity is about 4*105 Bq/kg. The following criteria are set for the Chernobyl NPP site for water to be disposed to the sewerage system: - Max. 37 Bq/kg for the total beta and gamma containing radionuclide activity; - Max. 0.7 Bq/kg for the total alpha containing radionuclide activity. METOIL produces inorganic sorbents for removing radionuclides from liquids and develops sorbent-based technology for a variety of applications related to liquid radioactive waste processing. In 2017-2018, experts from the Chernobyl NPP and METOIL ran several joint laboratory tests to evaluate the efficiency of inorganic sorbents made by METOIL for processing floor drains at the Chernobyl NPP. The test procedure included treatment of radioactively contaminated water in a two-stage sorption process: static sorption (sorbents are mixed in a liquid) and dynamic sorption (the liquid is filtered through a sorbent column). NIKET and MODIKS sorbents were provided for the tests. The results of the test measurements showed that the total alpha containing radionuclide activity is less than 0.026 Bq/kg and the total beta and gamma containing radionuclide activity is 9.2 Bq/kg. The physical and chemical parameters after processing also met the water disposal criteria. High sorption capacity of the sorbents used for the tests allows processing hundreds of water volumes with just one sorbent volume. At present, preparations are underway for full-scale tests at a pilot plant with a capacity of minimum 10 m{sup 3}/day. At a later stage, spent sorbents may be immobilized by inclusion into the cement matrix, which will substantially reduce the amount of radioactive waste to be buried. (authors)

• Research Organization: WM Symposia, Inc., PO Box 27646, 85285-7646 Tempe, AZ (United States)
• OSTI ID: 23005471
• Report Number(s): INIS-US--21-WM-19656
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
CEMENTING
CEMENTS
CESIUM 137
CHERNOBYLSK-1 REACTOR
COBALT 60
DRINKING WATER
EVAPORATION
LIQUIDS
MELTDOWN
MINIMIZATION
POTASSIUM 40
RADIATION ACCIDENTS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE PROCESSING
RADIOACTIVE WASTES
SOLID WASTES
SORPTION
STRONTIUM 90
WASTE PROCESSING PLANTS