Reducing radioactive contamination by sorption on impregnated water works sand

The feasibility was studied of using a sand filter bed for the deactivation of waste waters. This procedure is mainly suitable for the treatment of water into potable water. The advantage of the method is in that it allows partial regeneration of the sand fill. Results of pilot plant trials show that the effectiveness of the deactivation method depends on the composition of the sand fill, mainly on the MnO2 content, and increases with the increased content of this substance. It has also been proved that sands with a higher CaCO3 content are not only less effective but also more difficult to regenerate. The trapping of radium in the sand bed is not even and it was proved that the upper layers have a higher activity than corresponds to computations. (Z.M.)