Selection of compositions for the cementation of liquid radioactive waste of Kudankulam NPP and Volgodonskaya NPP

The purpose of this work is the selection of formulations for the cementation of liquid radioactive waste of Kudankulam NPP and Volgodonskaya NPP. The simulators of the following radioactive waste have been used for the works: concentrated still bottoms (CSB) with saline content 600-800 g/l, sludge, pulps of ion-exchange resins (IER), activated carbon, titanium and ion-exchange sorbents of Kudankulam NPP and concentrated still bottoms with saline content 900 g/l, pulps of ion-exchange resins, sludge of Volgodonskaya NPP. For Kudankulam NPP there was made a separate research of the cementation of each type of waste and also joint cementation of concentrated still bottoms and ion-exchange resin. For Volgodonskaya NPP - joint cementation of CSB and IER or sludge. The properties of the compounds were determined, which are regulated by GOST R 51883-2002, spread ability and setting time of the cement grouts. The study has shown that as a main component of the combined binding material for the cementation of low level radioactive waste (LRW) of Kudankulam NPP and Volgodonskaya NPP, the usage of Portland cement is preferable. As additives for the binding materials it is better to use lime and bentonite clay powder. Maximal inclusion of LRW into the compound when using these materials will be (% of the compound weight): CSB: 30%, sludge - 14%, IER - 14%, activated carbon - 18%, titanium sorbent - 20%, ion-selective sorbent - 14%