Abstract: A multiple hydrocyclone separator comprises a pair of spaced concentric standpipes mounting a series of mono hydrocyclones each having a body containing a separating chamber and provided with first and second cylindrical external parts on opposite ends of the body. The body has a tangential inlet to the chamber and a first axial outlet formed by a third part screwed into the larger end of the body, the body forming a second axial outlet at its smaller end. Sealing rings are located in grooves in the respective cylindrical parts and seal against the walls defining openings in the respective standpipes. To secure the body, a nut on its smaller end clamps the adjacent standpipe against a collar of the body. Thus, the cylindrical part at the larger end of the body can slide with its sealing ring in the hole of the corresponding standpipe, thereby accommodating thermal expansion and contraction of the body while maintaining the sealing action of the sealing rings.

Abstract: A multiple hydrocyclone assembly comprises a housing, a plurality of groups of radially extending cyclones provided at different levels in said housing, and inlet and outlet conduits connected to the bottom portion of the assembly. In order to avoid collection of air in the housing the outlet conduit comprises a central tube extending vertically through the housing to the top portion thereof.

Abstract: Each group of conical cyclone separators is arranged in an annular block with their longitudinal axes in a common plane, each side of each block having concentric sealing surfaces coacting with corresponding sealing surfaces of an adjacent similar block to seal against leakage from an inlet opening for supplying the separators. Preferably, the stack of blocks surrounds a central shaft for clamping the blocks together and forming a discharge path for the heavier constituent from the separators, the lighter constituent discharging from the separators at the outer periphery of the stack into a chamber surrounding the stack.