Patent ID: 9095794
Filing Date: 2015-08-04
Classification: B01D

Abstract:
1. A method of filtering a waste liquid comprising a suspension of waste particles using a filter apparatus comprising: (a) a housing defining an internal volume; (b) one or more liquid inlet ports defined by apertures in a wall of the housing; (c) one or more liquid outlet ports defined by apertures in a wall of the housing, the one or more liquid outlet ports disposed above the one or more liquid inlet ports; (d) a filter medium support membrane housed within the housing and disposed between at least one of the one or more liquid inlet ports and at least one of the one or more liquid outlet ports; (e) a filter medium source comprising a liquid suspension of a particulate filter medium that traps and filters waste particles from the waste liquid; (f) a filter medium charging tube comprising an inlet aperture in fluid communication with the filter medium source and an outlet aperture disposed within the housing below the filter medium support membrane; (g) a drain port defined by an aperture in a wall of the housing and configured to release liquid from the internal volume of the housing; and (h) an air vent in communication with the internal volume of the housing and configured to introduce air into the internal volume of the housing, the method comprising: introducing a liquid suspension of particulate filter medium into the internal volume of the housing through one of the one or more liquid inlet ports, wherein the liquid suspension flows upward through the support membrane, such that the suspended particulate filter medium is loaded against the lower surface of the filter medium support membrane; introducing the waste liquid into the internal volume of the housing through at least one of the one or more liquid inlet ports, wherein a liquid flow pattern is established that carries the waste liquid in an upward direction through the loaded filter medium support membrane and out of the internal volume of the housing through at least one of the one or more liquid outlet ports; and further wherein a first portion of the waste particles is carried with the waste liquid into the loaded filter medium support membrane, where they are trapped by the particulate filter medium, which filters them out of the waste liquid and prevents them from flowing out of the one or more liquid outlet ports with the waste liquid, and a second portion of the waste particles, having a higher average particle mass than the first portion of waste particles, falls to the bottom of the housing, under gravity, without being carried into the loaded filter medium support; discontinuing the introduction of the waste liquid into the internal volume of the housing; opening the drain port; replacing the flow of the waste liquid in the upward direction with a downward flow of air against the filter medium support membrane; and draining the waste liquid remaining in the internal volume of the housing and the particulate filter medium containing the filtered waste particles through the drain port; wherein the method does not include the step of backwashing water through the particulate filter medium to clean filtered waste particles from the particulate filter medium.