METHOD AND DEVICE FOR DECONTAMINATING NUCLEAR POWER PLANTS Russian patent published in 1997 - IPC

FIELD: nuclear power engineering. SUBSTANCE: contaminated unit is placed in pressurized chamber, spaces of chamber and unit ate connected to vacuum installation, flexible container with conducting external layer is inserted in unit space and filled with chemically active decontaminating solution. Decontamination is carried out by using electrochemical method; flexible container functions as one of electrodes and walls of nuclear power unit, as other electrode. Electrolysis is performed while solution is circulating doped in the process with gas-filled destructable-wall bodies. Dirty decontaminating solution is discharged to radionuclide compartment for further burial; fresh portions of solution are introduced in remaining quantity. Procedure is made until MPC norms are complied with. Decontaminating device is equipped with instrumentation and numeric-control unit, chamber for decontaminating nuclear power plant units connected in series with coarse and fine liquid-phase cleaning chambers. Coarse cleaning chamber is of variable sectional area and has diaphragms and separator placed at its outlet and provided with two pipes for discharging liquid to fine cleaning chamber and for supplying gas to remove radionuclides. Fine cleaning chamber has three chambers separated by membranes with cavities. Walls of one of them (central one) have cavities and depressions. Shaft installed along central chamber axis carries cup on its end with mushroom-shaped swirler and conical splitter to separate liquid from gases and solid admixtures. Aerosol collector is placed at outlet of three chambers. EFFECT: improved efficiency and capacity of decontamination process, reduced amount of wastes subject to storage, improved reliability, facilitated procedure. 5 cl, 10 dwg