A method and device for dewatering most liquid/solid solutions and slurries is described. A dewatering device having a dewatering pump in fluid communication with a filter rack with vertically arrayed filter elements that is carried by a container. To begin the dewatering process, the filter rack is lowered to the bottom of the container and the liquid/solid slurry is introduced. Next, the dewatering pump draws the liquid from the slurry into the filter rack and then to the pump. When dewatering efficiency decreases, the dewatering operation is momentarily stopped and the filter elements of the filter rack are backpulsed with air and raised to dislodge the filter cakes that have formed. The filter rack is then relowered and the dewatering operation continues. These steps of dewatering, backpulsing, raising the filter rack, and lowering filter rack are continued until the container is full of dewatered solids. Alternatively, the filter rack is affixed to the top of the container and the liquid/solid slurries are introduced until the container is mostly full. Next dewatering operations commence and continue until the container is full of dewatered solids.