Sludge Dewatering

Forniamo sistemi chiavi in mano completi per la disidratazione dei fanghi da depurazione delle acque reflue. Il sistema a centrifugazione lo consigliamo per fanghi derivanti dalla depurazione di tipo biologica, mentre la pressa a vite per fanghi derivanti dalla depurazione di tipo chimico fisico.


Centrifuges are machines used for the continuous dewatering of sludge through the process of centrifugation, a physical process that applies the force induced by the speed of rotation of a cylindrical structure on the sludge contained in it, in order to separate the solid phase from the liquid phase due to the different density of the two phases. The centrifugal decanter consists of a rotating drum with a horizontal axis inside which is a screw conveyor that rotates with differential speed compared to the drum itself. The sludge, by means of a progressive cavity pump and after the addition of a suitable polyelectrolyte, is fed into the decanter where, with the aid of very high acceleration (over 3000 G), the separation of the water from the solid parts takes place. Through adjustable overflow openings, the clarified water (centrate), separated from the solids, is discharged to the rear of the cylinder. The sludge enters from the same discharge side as the centrate; the separated solids are transported to the discharge point on the opposite side by the differential speed of the internal screw conveyor. A subject to a higher maintenance burden, can achieve significantly higher dewatering yields, especially for sludge that is easily dewatered and without the presence of abrasive compounds; it is typically applied to biological sewage sludge.

Screw presses

The screw press consists of a draining basket with variably spaced side openings, inside which is a screw conveyor supported on one side by the geared motor and on the opposite side by a floating bearing. Cleaning of the basket is ensured by a rubber profile integral with the screw conveyor coils. At the end of the machineS is a back pressure cone driven by pneumatically actuated pistons. The machine is completely enclosed by a casing with four side inspection openings (two on each side). Compared to the centrifuge, the screw press usually has a lower yield but, working at much lower rotational speeds, is more suitable for abrasive sludge (typically from chemical-physical treatments) and difficult to dewater with centrifugation.

Complete plants

The supply of the machines is completed with all accessories such as: polyelectrolyte preparer, sludge handling pumps, hydraulic circuit, steelwork support structure, thickener tank, screw conveyor for distribution of the dewatered sludge into the tank, and electric control panel.



Supply and installation of a double sludge dewatering system consisting of a centrifuge (sludge from biological purification) and a screw press (sludge from chemical-physical purification). The machines were positioned, elevated, inside a newly built metal structure, which through a mobile screw discharges the sludge into the three containers below. The system has successfully and more efficiently replaced the pre-existing filter presses and belt presses (guaranteed dry percentage and reduced management costs).

Waste sector

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Sede legale: Via Enrico Fermi 32 – 24020 Scanzorosciate (BG)

Sede operativa, magazzino e officina: Via A. Moro 1 – 24020 Scanzorosciate (BG)

Cap. Soc. € 500.000,00 i.v.

R.I. BG, Cod. Fisc. e P.I. 02887960165

Cod. Univoco SUBM70N

REA 331280

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