Cross-flow filtration device with filtrate flow conduits and method of forming same

A method of forming filtrate conduits in a monolith of porous material having a plurality of passageways extending from an upstream end to a downstream end of the monolith, comprising:

• selecting one or more of the passageways as filtrate conduit passageways for carrying filtrate from within the monolith to a filtrate collection zone, disposed along at least one side of the monolith, to distribute the filtrate conduit passageways among the non-selected passageways to provide low pressure drop flow paths from the non-selected passageways through the porous material to nearby filtrate conduit passageways, the surface area of the passageways being at least 100 square feet per cubic foot of the structure;
• establishing one or more channels to connect the filtrate conduit passageways to the filtrate collection zone;
• and
• sealing the filtrate conduit passageways to inhibit direct passage of fluid into the filtrate conduit passageways and the filtrate collection zone.

A cross-flow filtration device for receiving a feed stock at a feed end and for separating the feed stock into filtrate and retentate, comprising:

• a single monolith of porous material defining a plurality of passageways extending longitudinally from the feed end to a retentate end of the monolith through which the feed stock flows to pass retentate from the device;
• a filtrate collection zone disposed along at least one side of the monolith;
• a plurality of filtrate conduits formed within the monolith for carrying filtrate from within the monolith toward the filtrate collection zone, the filtrate conduits providing flow paths of lower flow resistance than that of alternative flow paths through the porous material;
• the filtrate conduits being distributed among the passageways to provide low pressure drop flow paths for filtrate flow through the porous material from the passageways to nearby filtrate conduits;
• the surface area of the passageways being at least 100 square feet per cubic foot of the monolith;
• and
• means for isolating the filtrate collection zone from the feed and retentate ends of the monolith.