Self-cleaning scroll and screen centrifuge

A centrifuge for processing a combined liquid and solid material and separating the liquid from the solid material comprising:

• a housing having
• front and rear walls,
• an exterior wall disposed between said front and end walls, and said front and end walls and said exterior walls defining an interior surface bounding a contained volume within said housing,
• an annular first housing sealing surface directed toward and concentrically located about an axis of rotation, and
• an annular second housing sealing surface extending from a front edge of said first housing sealing surface toward said exterior wall of said housing;
• a frustoconical basket and scroll assembly mounted within said housing to rotate about said axis of rotation, said frustoconical basket and scroll assembly having
• a circumferential wall section of an outer wall cooperating with said interior surface of said housing to form an enclosure therebetween, said enclosure receiving the liquid that is separated from the solid material,
• a rear section of said outer wall cooperating with said interior surface of said housing to form a cavity therebetween,
• a plurality of rings extending radially toward said exterior wall of said housing from said circumferential section of said outer wall proximate said rear section of said outer wall, said plurality of rings being contiguous with said first housing sealing surface, and
• an annular first slinger adjacent said plurality of rings and extending from said circumferential wall section of said outer wall toward said exterior wall of said housing in a direction adjacent and parallel to said second housing sealing surface, whereby said plurality of rings, said first slinger and said first and second housing sealing surfaces cooperating to form a first noncontacting seal separating said enclosure from said cavity, thereby inhibiting the flow of liquid from said enclosure to said cavity;
• and
• a plurality of fluid passages extending through said housing and terminating at said first housing sealing surface for injecting a cleaning fluid between said first housing sealing surface and said plurality of rings.

A centrifuge for processing a combined liquid and solid material and separating the liquid from the solid material, the centrifuge including a housing having an interior surface bounding a contained volume of the housing, the centrifuge further including a frustoconical basket and scroll assembly mounted for rotation within said housing, said frustoconical basket and scroll assembly having circumferential section of an outer wall cooperating with said interior surface of said housing to form an enclosure therebetween, said enclosure receiving the liquid that is separated from the solid material, and said outer wall of said frustoconical basket and scroll assembly including a rear wall section cooperating with said interior surface of said housing to form a cavity therebetween;

• the centrifuge comprising:
• noncontacting seal means connected to the housing and the frustoconical basket and scroll assembly for separating the enclosure and the cavity, thereby restraining a flow of liquid between the enclosure and the cavity;
• and
• means connected to said housing for injecting a fluid into said noncontacting seal means between said housing and said frustoconical basket and scroll assembly for cleaning said noncontacting seal means.

A centrifuge for processing a combined liquid and solid material to separate the liquid from the solid material comprising:

• a housing having an exterior wall including a front wall and an end wall and a peripheral wall disposed therebetween and an interior surface bounding a contained volume within said housing;
• a basket member mounted within said housing to rotate about an axis of rotation, said basket member having an outer wall cooperating with said peripheral wall of said housing to form an enclosure therebetween, said enclosure receiving liquid that is separated from the solid material, and said outer wall of said basket member including a rear wall section having an opening therein and cooperating with said end wall of said housing to form a cavity therebetween, said cavity being separated from said enclosure so that fluid is inhibited from flowing into said cavity;
• a scroll member mounted within said basket member to rotate about said axis of rotation relative to said basket member, said scroll member having
• a tubular side wall,
• a rear end wall closing one end of the tubular side wall and extending outward from the tubular side wall, and
• a helical screw flight extending outward from said tubular side wall and extending between a rear end and a front end of said scroll member, one end of said helical screw flight connecting with said rear end wall;
• and
• means extending into said cavity for injecting a fluid through said opening of said rear wall section of said basket member to clean surfaces located between said rear wall section of said basket member and said rear end wall of said scroll member.

A centrifuge for processing a combined liquid and solid material into a separated liquid from the solid material comprising:

• a housing having an exterior wall including a front wall and an end wall and a peripheral wall disposed therebetween and an interior surface adjacent said front wall;
• a basket member mounted for rotation about an axis of rotation within said housing, said basket member having
• a front side,
• a screen having a front edge formed to be adjacent said front side of said basket member,
• a clamping ring having a rear surface proximate said front side of said basket member for securing said front edge of said screen to said basket member,
• a cleaning blade mounted to a front surface of said clamping ring, said cleaning blade rotating with said basket member with respect to said housing for removing solid material from said interior surface of said housing,
• a fastener passing through said cleaning blade, clamping ring and connected to said basket member, and
• a teflon gasket located between said cleaning blade and said clamping ring, said teflon gasket having a thickness in the range of from 0.005 inches to 0.020 inches;
• and
• a scroll member mounted for rotation about the axis of rotation relative to said basket member and further having
• a tubular side wall having a closed rear end adjacent said closed end of said basket member, and
• a helical screw flight extending outward from said tubular side wall and extending between said rear end and said front end of said scroll member.

A centrifuge for processing a combined liquid and solid material to separate the liquid from the solid material comprising:

• a housing having a front wall, an end wall and a peripheral wall disposed therebetween;
• a basket and scroll assembly mounted for rotation about an axis of rotation within said housing, said basket and scroll assembly having a closed rear wall and a circumferential wall, and said basket and scroll assembly discharging liquid through said circumferential wall and discharging solid material from a front end adjacent said front wall of said housing;
• and
• said housing further including an annular discharge channel located concentrically about the axis of rotation between said front wall of said housing and said front end of said basket and scroll assembly, said annular discharge channel encompassing said front end of said basket and scroll assembly and receiving the solid material separated from the liquid, said annular discharge channel intersecting a generally vertical discharge chute to form an approximately rectangular discharge opening at a lowermost point of said discharge channel, said discharge opening having a width approximately equal to a width of the annular discharge channel as measured parallel to the axis of rotation, and said discharge opening having a length substantially less than a diameter of said annular discharge channel.

A centrifuge for processing a combined liquid and solid material into a separated liquid from the solid material comprising:

• a housing having an exterior wall including a front wall and a rear wall and a peripheral wall disposed therebetween and an interior surface adjacent the front wall;
• a basket member mounted for rotation about an axis of rotation within the housing, the basket member having a front edge;
• a screen having a forward lip formed over the front edge of the basket member;
• a clamping ring proximate the basket member for securing the forward lip of the screen to the basket member;
• a first gasket located between the clamping ring and one side of the forward lip of the screen;
• and
• a scroll member mounted for rotation about the axis of rotation relative to the basket member and further having
• a tubular side wall having a closed rear end adjacent the closed end of the basket member, and
• a helical screw flight extending outward from the tubular side wall and extending between the rear end and the front end of the scroll member.