Self-cleaning, continuously operating filter apparatus for fluids

Abstract

The filter apparatus for an incoming liquid which includes a retentate and a permeate includes a housing with a frame and a hollow drum assembly mounted for rotation within the housing about a fixed central cylinder. The drum assembly has openings in the drum wall. An inlet assembly delivers the incoming liquid under pressure to the drum assembly. A filter assembly is mounted to the inside of the drum. A trough assembly is mounted so as to be in communication with the central cylinder and is in a fluid-tight relationship to the interior surface of the filter assembly as the drum rotates past the trough assembly. A manifold is fixedly mounted but has a substantially fluid-tight relationship with the exterior of the drum, and is configured to cover successive columns of drum openings as the drum rotates. Pressurized gas is directed to the manifold at selected times, such that as the drum turns, and retentate is collected on the interior surface of the filter as the incoming liquid is forced through the filter assembly, pressurized fluid from the manifold dislodges the retentate off into the trough and out the outlet assembly.

1 . A filter apparatus for an incoming fluid having a retentate and a permeate, comprising:
 a support frame;   a container assembly for incoming fluid mounted for rotation by the support frame and having openings therethrough;   an inlet assembly for delivering the incoming fluid to the container assembly;   a filter assembly mounted to or part of the inside of a portion of the container assembly;   an outlet assembly;   a trough assembly mounted in fluid communication with the outlet assembly and having a sealing surface contacting an interior surface of the filter assembly;   a manifold having a sealing edge for contacting an exterior surface of the container assembly; and   a source of pressurized fluid connected to the manifold, wherein, as the container assembly turns in operation, retentate is collected on the interior surface of the filter as the permeate moves through the filter and container assembly and out of the apparatus, the collected retentate being dislodged from the filter, moving into the trough assembly and from there into the outlet assembly by periodic bursts of pressurized fluid.   
     
     
         2 . The filter apparatus of  claim 1 , wherein the filter assembly includes a sealing surface which the sealing surface of the trough assembly contacts and further includes an active filter layer which is protected from wear by the sealing surface of the filter assembly. 
     
     
         3 . The filter apparatus of  claim 1 , including a housing assembly in which the container assembly is positioned, wherein the permeate moves from the container assembly into the interior of the housing assembly, the housing assembly further including an exit line therefrom for the permeate. 
     
     
         4 . The filter apparatus of  claim 1 , wherein the container assembly is a drum-configured assembly. 
     
     
         5 . The filter apparatus of  claim 1 , including a programmed controller for controlling the operation of the apparatus. 
     
     
         6 . The filter apparatus of  claim 4 , wherein the drum assembly includes two opposing end portions and an intermediate portion, wherein the intermediate portion includes a plurality of openings therein arranged into a pattern of rows and columns, the column openings extending between the end portions and the rows extending around the periphery thereof at spaced intervals. 
     
     
         7 . The filter apparatus of  claim 6 , wherein the filter apparatus further includes a central cylinder which extends through the housing and around which the drum rotates, and wherein the inlet assembly includes an inlet cylinder which surrounds and is slightly larger than the central cylinder, wherein the inlet cylinder extends through a top end portion of the drum, the inlet assembly further including a connecting line for receiving the incoming liquid, wherein the incoming liquid enters the drum between the inlet cylinder and the central cylinder in the vicinity of the top end of the drum. 
     
     
         8 . The filter apparatus of  claim 1 , wherein the inlet assembly includes a pump which delivers fluid into the container assembly under pressure, the interior of the container thus being pressurized, except for a volume defined by the trough assembly, which is not pressurized. 
     
     
         9 . The filter apparatus of  claim 8 , wherein the pressure within the container is within the range of 0-100 psi. 
     
     
         10 . The filter apparatus of  claim 9 , wherein the pressure is 10-20 psi. 
     
     
         11 . The filter apparatus of  claim 7 , wherein the trough assembly is in communication with the interior of the central cylinder, and wherein the central cylinder extends out of the housing, so that material which moves into the trough assembly and then into the central cylinder moves out of the apparatus for disposal/recovery thereof. 
     
     
         12 . The filter apparatus of  claim 7 , including cylindrical sections which extend outwardly from the respective end portions thereof, defining openings through the end portions into the interior of the drum assembly, and wherein the apparatus further includes a substantially fluid-tight seal and a bearing between the cylindrical sections, respectively, and the inlet cylinder at the top end portion and the central cylinder at the bottom end portion of the drum assembly. 
     
     
         13 . The filter apparatus of  claim 11 , wherein the trough assembly includes a box-like member which extends from the outlet assembly and is in communication therewith, a seal support member and a seal therein which extends around an upper edge of the box assembly, the seal being in physical contact with a surface of the filter assembly, and spring members arranged and mounted so as to bias the trough assembly seal against the filter surface. 
     
     
         14 . The filter apparatus of  claim 1 , wherein the incoming liquid is waste water from laundries and the retentate is primarily lint. 
     
     
         15 . The filter apparatus of  claim 1 , wherein the manifold is a box-like member with a seal around a free edge thereof which is arranged to contact the exterior surface of the container in a substantially fluid-tight manner, and wherein the manifold box member is configured to cover at least one column of the openings in the container, and wherein the box member includes means for receiving pressurized fluid from an external source thereof. 
     
     
         16 . The filter apparatus of  claim 15 , wherein the pressurized fluid is air, water or steam. 
     
     
         17 . The filter apparatus of  claim 2 , wherein the filter assembly includes an inner layer of perforated metal, a fine mesh layer, a coarse mesh layer and at least one extra coarse mesh layer. 
     
     
         18 . The filter apparatus of  claim 17 , wherein the fine mesh layer has openings on the order of  2  microns, and wherein the coarse mesh layer and the extra coarse mesh layer are several times coarser than the fine mesh layer. 
     
     
         19 . The filter apparatus of  claim 17 , including a plurality of spaced rubber strips which extend the length of the filter assembly and in the vicinity of the ends of the filter assembly and impregnate the fine, coarse and extra coarse layers, providing a substantially fluid-tight seal between adjacent rubber strips and the interior surface of the container assembly.