Sealing Roofs of Radioactive Waste Storage Facilities and Other Radiation-Hazardous Facilities Using Polymer Compositions

The article examines the use of protective polymer coatings (PPCs) for the long-term protection of various surfaces from radioactive contamination at nuclear power plants and other radiation-hazardous facilities. Regulatory documents governing the procedure for confirming that newly developed technologies comply with safety requirements in the field of atomic energy use are analyzed. The insufficiency of available solutions and the inadequate effectiveness of polymer compositions, which adversely affect their applicability for sealing roofs of near-surface radioactive waste storage facilities, are demonstrated. An original technology for sealing the storage roof and a formulation for preparing a protective polymer composition are developed and tested under the conditions of near-surface solid radioactive waste storage facilities at the Novovoronezh NPP. The method for sealing the roofs of radioactive waste storage facilities and other radiation-hazardous facilities includes pretreating the surface to be sealed by applying two protective layers of different compositions (the first layer is a primer, i.e., insulating layer based on a water‑dispersion paint with localizing additives, and the second layer is an easily decontaminated layer based on nitro‑epoxy enamel) and coating the surface with the EGAiB protective sealing composition. In order to apply and form the first preparatory layer, a composition based on a water‑dispersion paint with additives, carboxylic acid and piperazine, is used. In order to form the second pretreatment layer, EP‑51 nitro‑epoxy enamel is used. The EGAiB sealing composition based on the VD EPEP‑72 epoxy‑diane resin is used to form the main protective layer, the modifier is a glycidyl ether of polyhydric alcohols, the flame retardant is HP‑110 chloroparaffin, the hardener is tertiary aminophenol, and the solvent is acetone according to GOST (State Standard) 2768‑84. The test results confirmed high performance characteristics and the promise of further research in this area. On the basis of the results of tests and verification of the operational and technological properties of composite materials (based on PVB and epoxy resins), it was found that polymer compositions based on polyvinyl butyral and epoxy resins with specific additives and resin properties can be recommended for use on roofs with concrete–asphalt coatings of near‑surface solid radioactive waste storage facilities.