System for removing liquid from slurries of liquid and particulate

Abstract

In order to separate liquids from slurries containing particulate material, and particularly from slurries of water and spent ion exchange materials which are used for water conditioning in the operation of nuclear power plants and must be disposed of without any significant volume of free standing water therein, a vessel is provided which is filled with the slurry. The bottom of the vessel is conical and defines a region for the collection of water which passes thereto radially through a structure which filters the water and supports a bed of the particulate material thereon. A discharge tube extends longitudinally of the vessel into the region. A level sensor is disposed alongside the tube. A passage into the top of the vessel is provided for blowing air through the bed to force interstitial water through the bed into the region. A system of pumps and blowers is operated in accordance with the level of liquid and solid material in the vessel so as to provide for discharge of the liquid collected in the region, the formation of a tightly packed bed of particulate material and the blowing of air through the bed after substantially all the water has been discharged so as to free additional water and enable it to be discharged, thereby removing the liquid from the slurry and de-watering the material in a relatively short period of time to the extent required by governmental regulations for the disposal of low level radioactive waste materials (radwaste), for example in eight hours, and providing efficient utilization of the volume of the vessel in preparation for storage.