Scroll decanter centrifuge

Theoretical studies (30) comparing the ability to dewater compressible solids by sedimenting and filtering centrifuges to pressure filters, have shown that at high G levels, scroll decanters produce drier cakes than pressure filtration. 

Decanter Centrifuges The decanter centrifuge (also known as the solid-bowl or scroll centrifuge) consists of a solid exterior bowl with... 

Scroll/decanter Continuous 5-50,000 200 1. Continuous solid discharge 2. High-feed solid concentration 1. Turbulence created by scroll 2. Low centrifugal force Antibiotic production... 

Solid bowl scroll decanter centrifuges have also been built vertically. The pendulum-type construction allows the bowl to expand more easily when operating at higher temperatures and makes mechanical sealing for elevated pressures less cumbersome. Although these units have been designed for operation up to 10 bars, they often operate at 5 bars or less. 

Figure 1.14 Schematic diagram of a horizontal axis scroll decanter centrifuge. The motor drive for the bowl and the gearbox required to produce the differential rotation speed between the bowl and screw conveyor are omitted for clarity.

Figure 4.14. Separation of cell lysates containing pharmaceutical products, employing large-capacity centrifuges that are configured with tubular bowl (A), multi-chamber bowl (B), disc stack bowl (C), or decanter (scroll) bowl (D).

Figure 3.5 Clarifying decanter (horizontal scroll centrifuge). Source Courtesy of Westfalia Separator Ltd.

The Sorticanter has a scroll with reversing pitch on one side, which skims a floating solids layer off the top of the carrier hquid, usually an aqueous brine of intermediate density. Sinking solids are scrolled out similarly to normal decanter centrifuges, and liquid is discharged under pressure via a stationary but variable impeller. The Sorticanter is utihzed in the plastics recycling industry. 

As in a decanter, an accelerated feed is introduced to the separation pool. The denser solids settle toward the bowl wall and the effluent escapes through the ports at the large end of the machine. The sediment is scrolled toward the beach, typically with a steeper angle compared to the decanter centrifuge. As the solids are conveyed to the... 

Laboratory test tube centrifuges can determine if there is a sufficient density difference between the two phases to consider sedimentation as an alternative. If there is a sharp separation, one can anticipate the same in the field. One can also answer the following questions. Do the solids settle or float Is the solid phase granular or amorphous What is the moisture content The characteristics of the solids indicate the solids discharge design required, i.e., scroll in decanters, or in disk centrifuges, flow-through nozzles or wall valves. 

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