Patent ID: 8128829

Claim:
A method of increasing the filtrate output in cross-flow filtration, the method comprising: providing a cross-flow filter device having a housing in which a first longitudinal filter element and a second longitudinal filter element are arranged concentrically about a longitudinal axis thereof and defining a space between the first and second longitudinal filter elements, the first and second longitudinal filter elements ensuring the increased filtrate output; defining a raw material inlet in the cross-flow filter device for raw material to be filtered, the inlet being connected to the space between the first and second longitudinal filter elements; introducing the raw material into the raw material inlet; the raw material having a flow direction through the first longitudinal filter element from the space between the first and second longitudinal elements to the outside of the first longitudinal filter element and through the second longitudinal filter element from the space between the first and second longitudinal elements to the inside of the second longitudinal filter element; defining a concentrate outlet in the cross-flow filter device, the concentrate outlet being connected to the space between the first and second longitudinal filter elements; extracting a concentrate from the concentrate outlet of the cross-flow filter device, the concentrate comprising raw material that is substantially enriched in particles; defining a first filtrate outlet in the cross-flow filter device, the first filtrate outlet being connected to the first longitudinal filter element; extracting a first filtrate from the first longitudinal filter element of the cross-flow filter device, the first filtrate comprising a medium that is substantially depleted in particles; defining a second filtrate outlet in the cross-flow filter device, the second filtrate outlet being connected to the second longitudinal filter element; extracting a second filtrate from the second filter element of the cross-flow filter device, the second filtrate comprising a medium that is substantially depleted in particles; and wherein the flow of raw material and the flow of the first and second filtrates are substantially in the same direction through the cross-flow filter device.