초록 ▼

Rotary disc filtration devices and filtration processes using those devices are disclosed. The devices have one or more fluid filtration gaps into which fluid to be filtered into permeate and retentate is placed. Each fluid filtration gap is defined by a disc and a filter, one of which rotates with

Rotary disc filtration devices and filtration processes using those devices are disclosed. The devices have one or more fluid filtration gaps into which fluid to be filtered into permeate and retentate is placed. Each fluid filtration gap is defined by a disc and a filter, one of which rotates with respect to the other. The filter is carried on a filter support member. Fresh feed is introduced to each fluid filtration gap near the longitudinal axis of the shaft on which the discs are rotated. Holes through the disc in the active area of the disc, which is the area opposite the filter, counteract the tendency of the disc and filter to move towards one another.

대표청구항 ▼

[ We claim:] [44.] A method for reducing the tendency for a rotary disc and a filter defining a fluid filtration gap in a rotary disc filtration device to be forced together by the pumping action caused by the rotation of the disc during the filtration process, the rotary disc filtration device comp

[ We claim:] [44.] A method for reducing the tendency for a rotary disc and a filter defining a fluid filtration gap in a rotary disc filtration device to be forced together by the pumping action caused by the rotation of the disc during the filtration process, the rotary disc filtration device comprising: (a) one or more filter support members each having first and second oppositely disposed major faces, each major face having a filter with (i) an active filtration area, (ii) a peripheral region, and (iii) a longitudinal axis substantially perpendicular to the active filtration area; (b) one or more discs mounted on a rotatable shaft and in alternating interleaved relationship with the filter support members to define a plurality of fluid filtration gaps, each disc having first and second oppositely disposed major faces, each major face having an active area and a peripheral region, the shaft having a longitudinal axis of rotation; each fluid filtration gap being defined by the active area of one of the discs and the active filtration area of the adjacent filter, the active area of the second major face of each of the one or more discs having at least one spiral groove in fluid communication with the fluid when fluid is in the fluid filtration gap defined by the second major face, the spiral groove subtending an angle Y in polar coordinates of at least ten degrees on the second major face of the disc; (c) rotation means for rotating the shaft so that the one or more discs rotate with respect to the filters and a pumping action is created that tends to move fluid in the fluid filtration gaps in a direction away from the longitudinal axis of the shaft; and (d) first feed means for feeding feed fluid to each of the fluid filtration gaps near the longitudinal axis of the shaft; the method comprising providing second feed means in at least one of the one or more discs having a spiral groove for feeding fluid adjacent the active area of the first major face of the disc through the active area of the second major face of the disc to the fluid filtration gap defined by that second major face.