Patent ID: 8591745

Claim:
A method of filtration comprising a. providing a source of fluid to be filtered, a source conduit connecting the source to an inlet of a filtration device, i. the filtration device comprising a housing containing one or more filter cartridges, ii. the one or more filter cartridges being normal flow filtration filter cartridges, the one or more filter cartridges being in fluid communication with a housing outlet which is in fluid communication with an outlet conduit connecting the outlet to a downstream component and to a backflushing loop, iii. the downstream component being selectively closable by a normally open downstream component valve and the backflushing loop being selectively openable by a normally closed backflushing loop valve, iv. the backflushing loop for the filtrate comprising a backflushing conduit connecting the outlet via the backflushing loop valve to a filtrate tank, the tank having a tank outlet connected to a tank conduit back to the housing outlet wherein the tank conduit is normally closed off from the housing outlet by a tank conduit valve, v. the inlet and the outlet of the housing being located at an uppermost portion of the housing and a drain being located at a lowermost portion of the housing, vi. one or more ports formed in the side of the housing adjacent the one or more filter cartridges, the one or more ports being connected to a side of the housing adjacent the one or more filter cartridges, the port(s) being connected to the source conduit by a port conduit controlled by a port valve; b. supplying the fluid to be filtered through the source conduit and into the inlet of the housing; c. passing the fluid through the one or more filter cartridges and into the outlet and into the outlet conduit and past the downstream component valve to the downstream component; d. selecting a parameter selected from the group consisting of length of time of filtration, transmembrane pressure differential of the one or more filter cartridges measured at the inlet and the outlet and flow rate reduction of the fluid measured at the inlet and the outlet; e. monitoring the selected parameter to determine when a preset value of the parameter is reached or exceeded; f. upon reaching or exceeding the preset value of the selected parameter, closing the downstream component valve, opening the drain and opening the tank conduit valve to direct filtrate back through the outlet and the one or more filter cartridges into the housing and out the drain for a period of time sufficient to backflush the filter cartridges; g. dosing the tank conduit valve and drain and opening a reequilibration valve and reequilibration conduit between the downstream component valve and the outlet conduit and the source conduit for a desired period of time to recirculate the fluid, and h. closing reequilibration valve and reequilibration conduit and reopening the downstream component valve and reinitiating the supply of the fluid from the inlet to the one or more filter cartridges to reinitiate the filtration process.