Improved dewatering characteristics of uranium-industry leach pulp using flocculants and surfactants

The filter cake from the vacuum drum filters of a uranium ore processing pl ant still contains some leach solution. If the filter cake is not efficient ly washed the associated leach solution is lost. Therefore, it is necessary to produce a filter cake that is permeable enough to allow efficient washi ng. The dewatering characteristics of the solid-liquid system must be impro ved to obtain flocs with sufficient strength to withstand the suction press ure of the filtration system. To facilitate efficient filtration with minim um cake moisture, studies were undertaken to improve the dewatering charact eristics of the cake using different types of flocculants and surfactants. In these studies,flocs were formed with anionic, cationic or nonionic flocc ulants. The best performance was obtained with a low cationic high molecula r weight flocculant. The filtration parameters, namely, capillary suction t ime, cake resistance, cake permeability and final moisture content of the f ilter cake, are improved by using a combination of flocculant and nonionic surfactant.