The Flottwg Z Series Decanter Centrifuge

centrifuge-z8e-thumbThe Flottweg Z Series was developed specifically for robust industrial applications and is used worldwide in the following applications.  These are typical examples taken from in excess of 300 applications for which the Z Series is suitable .

Of all modern industrial centrifuges, solid bowl centrifuges have the broadest range of applications.

Vegetable/Food/Animal Chemical/Pharmaceutical Products Minerals
Algae Aluminium Hydroxide Bauxite
Animal fat Barium Sulphate Bentonite
Blood Basic dyes Calcium Carbonate
Brewers yeast Calcium fluoride Carbide sludge
Biodiesel Calcium sulphate Clay
Bioethanol Colour pigments Copper extraction
Biogas Cryolite Graphite
Casein Dimethylterephthalate (DMT) Gypsum
Cellulose derivatives Epoxy resin Iron hydroxide
Coffee Fluorescents Kaolin
Fermentation products Iron oxide Magnesium hydroxide
Fish meal Latex Mica
Fish oil Lead oxide Silica
Fish pump water Phosphate compounds Silicium
Fleshings Phosphoric acid Silicon carbide
Fruit juice Plastic derivates/additives  
Gelatin Polyethylene (HDPE) Environmental Protection /Recycling
Kieselguhr Polypropylene Drilling mud
Lactose Polystyrene Industrial wastewater
Lignin PVC Manure
Meat Salts Municipal wastewater
Molasses Silicate Organic waste
Pectin Sodium chloride Paint sludge
Potato Titanium oxide Plastic sorting
Protein Tricalcium phosphate Sand and gravel washings
Sorbose Zinc carbonate Steelwork sludge
Soy protein Zinc oxide
Spent grains Zinc sulphate Mineral Oils
Starch Tar cleaning
Stillage Oil sludge
Surimi Slop oil treatment
Vegetable extracts
Vegetable juice
Vegetable oils


The product is fed through a stationary pipe into the feed zone located in the center of the scroll. It is then accelerated circumferentially and delivered through distribution ports into the bowl.



The bowl has a cylindrical/conical shape and rotates at a pre-set speed optimally adjusted to the application. The slurry rotates with the bowl at the operating speed and forms a concentric layer at the bowl wall.

The solids contained in the product are packed firmly against the bowl wall by centrifugal force. The length of the cylindrical bowl section and the cone angle are selected to meet the specific requirements of an application.


The scroll rotates at a slightly different speed than the bowl and conveys the separated solids toward the conical end of the bowl. This differential speed determines the residence time of the solids in the bowl. Residence time is a critical factor for cake dryness. It can be adjusted by changing the differential speed of the scroll thus providing optimal separation. If the physical properties of the product change, FLOTTWEG DECANTERS can be supplied with a different scroll design or by modifying an existing scroll.

Scroll pitch and single or multiple lead configurations are important design variables

Solids Discharge

Settled solids are ejected through ports at the conical end of the bowl into the solids housing and fall through the discharge chute.



FLOTTWEG uses high-quality stainless steel for all product wetted areas.

The bowl and scroll body are made of high-strength centrifugal Duplex stainless steel castings.

Rotor Bearings

A special selection and arrangement of bearings provides for long life and exceptional reliability. There are various lubrication systems to utilise either grease or oil to bearings depending on the model and the application.

Overview Weirs

The clarified liquids flow to the cylindrical end of the bowl where they exit over weir plates. Easily adjustable weir plates allow for precise adjustment of the pond depth in the bowl.

The liquid overflow is then collected in a centrate chamber and discharged by gravity.

Fully Adjustable Impeller (Skimmer)

The clarified liquid can also be decanted with an impeller and discharged from the bowl under pressure. This eliminates the need for a separate chamber pump. The FLOTTWEG adjustable impeller is an engineering refinement that permits quick and precise adjustment of the pond depth during operation to accommodate for changing process conditions.