Scroll discharge centrifuge

Centrifuge. Scroll discharge centrifugal sedimentor/filter, bowl diam. 32 in, stainless steel, 60 hp. 

In a scroll discharge machine, the solids deposited on the wall of the bowl are removed by a scroll (a helical screw conveyer), which revolves at a slightly different speed from the bowl. Scroll discharge centrifuges can be designed so that solids can be washed and relatively dry solids be discharged. 

To recover liquid and solids in order of preference of settlers. Section 5.8, CCD, Section 5.11 and sedimentation centrifuges. Section 5.12 continuous countercurrent decanter circuit CCD, horizontal solid bowl centrifuge with scroll discharge. 

Figure 8.4 Three common sedimenting centrifuge designs. A) Scroll discharge decanter, B) Tubular bond C) Disc stack, no solids discharge [Courtesy of Alpha Laval Separation Ltd.]...

The solid-bowl scroll-discharge centrifuge — now almost universally known as the decanter centrifuge — has, indeed, become the workhorse of a wide range of liquid/solid separation activities. Its application to the dewatering of waste sludges has made it a most valuable tool in combating environmental pollution. This has made the decanter a well-known and widely appreciated piece of equipment. 

Decanter centrifuges, for process applications, are typically solid bowl scroll-discharge machines, capable of continuous sohd and centrate discharge. They are ideally suited to handling high feed solids concentrations and delivering dry solid products. They are generally able to convey the soft solids often encountered in the pharmaceutical and fermentation industries. 

Disk machines having nozzles to discharge the solids phase through small backward-pointing nozzles must have this power included in the calculations. Some thickening scroll centrifuges also use such nozzles, usually with an intermittent flow. Pp] is the nozzle power ... 

Scroll centrifuges discharge solids continuously and usually drier than disk and imperforate batch types. Generally disk centrifuges have the highest values of Z or KQ for a given size and therefore the best ability to collect fine particles at a high rate. 

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