A screw centrifuge has a rotating, cylindrical drum (11) with openings (14,15) for discharge of settleable solids (16), floating solids (17), and separating liquid (18). A rotatable shaft (12) has openings (22) for infeed of the solids to be separated, and two sections of screw flights (13,13′,13″,23,23′) working in opposite directions. A baffle disc (20) is arranged on the shaft between the infeed opening (22) and the discharge opening (14) for the settleable solids (16). The flight (13′,13″) of the screw for the settleable solids (16) surrounds the flight (23,23′) of the screw for the floating solids (17), and also work in opposite directions. The screw section for the floating solids (17) is designed as a multi-channel screw. The outer flight (13′,13″) of the screw for the settleable solids (16) can also have several channels.

A decanter centrifuge that carries out solid-liquid separation by centrifugal force on an object to be processed that is fed into a rotating bowl and designed from a solid and a saturated solution wherein that solid is dissolved, and discharges solid phase components from a solid discharge opening and discharges liquid phase components from a solvent discharge opening thereof by rotationally operating a screw conveyor disposed within the rotating bowl, said decanter centrifuge being provided with a dilution solvent supply unit for supplying, during centrifuging of the object to be processed, dilution solvent that reduces the concentration of the saturated solution to a discharge path, which is a discharge path for saturated solution moving within the rotating bowl, and which is designed closer to the solvent discharge opening side—than a chamber for supplying the object to be processed.

A decanter centrifuge that carries out solid-liquid separation by centrifugal force on an object to be processed that is fed into a rotating bowl and designed from a solid and a saturated solution wherein that solid is dissolved, and discharges solid phase components from a solid discharge opening and discharges liquid phase components from a solvent discharge opening thereof by rotationally operating a screw conveyor disposed within the rotating bowl, said decanter centrifuge being provided with a dilution solvent supply unit for supplying, during centrifuging of the object to be processed, dilution solvent that reduces the concentration of the saturated solution to a discharge path, which is a discharge path for saturated solution moving within the rotating bowl, and which is designed closer to the solvent discharge opening side—than a chamber for supplying the object to be processed.

Provided is a method for producing a toner particle including a step of condensing a raw slurry by using a decanter-type centrifugal separator, in an aqueous medium. The step of condensing the raw slurry is carried out under following conditions: a centrifugal force is at least 500 G and less than 4000 G and a temperature is at least Tg−10° C. and not more than Tg+10° C. And a ratio of a colored particles in condensed slurry is within a prescribed range.

Provided is a method for producing a toner particle including a step of condensing a raw slurry by using a decanter-type centrifugal separator, in an aqueous medium. The step of condensing the raw slurry is carried out under following conditions: a centrifugal force is at least 500 G and less than 4000 G and a temperature is at least Tg−10° C. and not more than Tg+10° C. And a ratio of a colored particles in condensed slurry is within a prescribed range.

A solid bowl screw centrifuge includes a housing and a rotor rotatably mounted in the housing. The centrifuge has a rotatable drum having an axis of rotation, the drum having a cylindrical section having a length L.sub.1 and a conical section having a length L.sub.2. The centrifuge also has a first inlet for feeding a suspension to be processed into the drum and a liquid outlet arranged in the cylindrical section of the drum and a solids outlet arranged in the conical section of the drum. A screw is arranged in the drum and rotatable at a differential speed relative to the rotatable drum, the drum and the screw together forming the rotor. The centrifuge also a second inlet for supplying an additive to a solid phase within the drum.

A solid bowl screw centrifuge includes a housing and a rotor rotatably mounted in the housing. The centrifuge has a rotatable drum having an axis of rotation, the drum having a cylindrical section having a length L.sub.1 and a conical section having a length L.sub.2. The centrifuge also has a first inlet for feeding a suspension to be processed into the drum and a liquid outlet arranged in the cylindrical section of the drum and a solids outlet arranged in the conical section of the drum. A screw is arranged in the drum and rotatable at a differential speed relative to the rotatable drum, the drum and the screw together forming the rotor. The centrifuge also a second inlet for supplying an additive to a solid phase within the drum.

A decanter centrifuge includes one or more nozzles through which a slurry may be discharged from a feed chamber into a separation zone within a centrifuge bowl. A scroll conveyor may be coaxially aligned in the separation zone within the centrifuge bowl around the circumference of the feed chamber. In the separation zone, the slurry can be separated into at least a light phase and a heavy phase by centrifugal acceleration generated by rotation of the centrifuge bowl, the feed chamber, and/or the scroll conveyor. Each separated phase can discharge from the centrifuge bowl via respective discharge ports. Each nozzle may include a rectangular aperture and differentiated profiles of its leading edge and trailing edge. In some embodiments, the leading edge of the aperture comprises a rounded profile, while the trailing edge comprises an abrupt edge or a less-rounded edge.

A decanter centrifuge includes one or more nozzles through which a slurry may be discharged from a feed chamber into a separation zone within a centrifuge bowl. A scroll conveyor may be coaxially aligned in the separation zone within the centrifuge bowl around the circumference of the feed chamber. In the separation zone, the slurry can be separated into at least a light phase and a heavy phase by centrifugal acceleration generated by rotation of the centrifuge bowl, the feed chamber, and/or the scroll conveyor. Each separated phase can discharge from the centrifuge bowl via respective discharge ports. Each nozzle may include a rectangular aperture and differentiated profiles of its leading edge and trailing edge. In some embodiments, the leading edge of the aperture comprises a rounded profile, while the trailing edge comprises an abrupt edge or a less-rounded edge.

A hermetically sealed horizontal washing decanter centrifuge for enhanced drilling fluid recovery and drilled solids washing. A process and apparatus for liquid phase-solid phase separation of oil based drilling mud-containing drill cuttings is described including flowing the drilling mud-containing drill cuttings into a horizontal washing decanter wherein the stresses imposed within the decanter act as a wash as the diluent and oil based drilling mud move away from the drill cuttings. Diluent is added prior to flowing the drilling mud containing drill cutting to the hermetically sealed horizontal washing decanter centrifuge. The entire process is performed in a gas-tight environment preventing escape of diluent from the process into the external atmosphere and preventing introduction of gases into the process from the external atmosphere.