D&D Experience in VNIINM Available to Purchase

Since the mid-1960s the VNIINM has been developing decontamination techniques for a variety of materials and contaminants for Russian nuclear engineering needs. 1. Early in the development, chemical decontamination was the most commonly used method. According to the nature of contaminants and contaminated material, mineral acids, alkali, mineral and organic oxidants and reductants were used. For best results, complex forming agents were sometimes added. However, in spite of widespread use of chemical decontamination at the USSR nuclear facilities, this technique has a drawback of producing a great deal of secondary liquid radwaste. Since the early 1970s attention has focused on the reduction of radwaste. Currently, optimized electrochemical and strippable coating methods are showing the greatest promise. 2. A low-waste dry decontamination technique based on application of readily strippable polymeric (protecting, decontaminating, immobilizing) coats has been developed and tested in the laboratory and wide scale. A low-waste dry decontamination technique based on application of readily strippable polymeric (protecting, decontaminating, immobilizing) coats has been developed and tested in the laboratory and wide scale. 3. VNIINM has developed a few electrochemical decontamination procedures and equipment surface decontamination. 4. One of VNIINM’s laboratory rooms which had been put to prolonged storage after an incidental alpha-radioactivity release was chosen for tests and demonstration. At first, the radioactivity levels inside the room on all the surfaces were measured. On outer surfaces, the alpha-activity was 1–15 α-particles/min.cm², the gammaactivity varied from 720 to 2880 mkrem/s. The room was equipped with instrumentation and apparatures located in three chains of gloveboxes and hot cells for handling Pu-bearing materials. Continuous checks of the airborne radioactivity and the personnel residence time inside the room were performed. 5. Old Pu extraction facility (U-5) was decontaminated and decommissioning in VNIINM in 1999–2000. This facility is a system of interconnected working areas housing process equipment located in 4 floor building and includes more than 20 laboratories rooms, 2 “hot cells”, few sealed contaminated rooms and two extraction shaft. Industrial separation technologies have been tested on the facility for 20 years since 1947. The first USSR Pu was obtained here. Practically all rooms were contaminated with Pu, Cs, Sr etc. The experimental equipment of two hot cells (63 m² each cell) control and service rooms was decontaminated and certified. The dissolution equipment, the metering tank compartment was decommissioned and removed. 16 laboratory rooms with a total area of 300 m² were rehabilitated and certified. The amount of waste removed exceeded 12 500 kg. All rooms rehabilitated were certified and accepted by sanitary control service for further use. 6. At the time old contaminated room contains a non standard radiochemical equipment includes glove boxes is under decommissioning procedure. This project started at 2002.