Used Alfa Laval Centrifuges.
Alfawest specialises in Alfa Laval Centrifuges for different types of processes. Alfa Laval Centrifuges are all reconditioned and tested. We also offer service and sales of others brands such as: GEA, Pieralisi and Flottweg. We have more than 30 years of experience working with various types of centrifuges and we are committed to offering an excellent service. Each of our machines is disassembled and meticulously inspected and many of its parts such as bearings, gaskets, seals, springs, etc. are changed. If we don’t have the machine that you need we can find one and make sure that the quality is good. Most of the second hand centrifuges need to be checked properly before you decide to buy it. We are here to help you to find the right machine for your process. There are many different designs of centrifuges and not all of them can be used for the same process. Each machine is designed for a specific task.
Alfawest supplies used, but generally overhauled centrifugal separators made by Alfa Laval ( Tetra Pak),GEA Westfalia Separator and Flottweg for the centrifugal separation of solids and liquids.
Every separator is subjected to a comprehensive general overhaul and subsequently delivered with a mechanical guarantee. Furthermore the separators can also be fitted with new PLC systems and control panel.
The scope of the Alfawest Service includes all the separator types on the market (e.g. separators with automatic discharges, solid bowl or nozzle.
Alfawest supplies used, but refurbished disc separators made by GEA Westfalia Separator and Alfa Laval (Tetra Pak) for the most varied areas of use.
The disc separator has a drum chamber, which, in order to increase the equivalent purifying surface is fitted with a large number of conical so-called “discs”. With regards to the discharge of the purified respectively the liquid phases separated from each other all disc separators work continuously. A disc separator can be delivered in the purifying separator version (also named purifier or clarificator) as well as in the separator version (also named separator or purifier respectively concentrator). With regards to the discharge of the solid material the situation can be described as follows:
Disc Separator- Automatic Discharging
Self-discharging or also self-cleaning, self-emptying or automatic separator operate with respect the discharge of the solid material partially continuously (pseudo continuously) and are characterised by the fact that the solid material in the drum, spun off by the centrifugal force, can be periodically discharged without the disc separator having to be stopped. This is achieved by the lower part of the double coned solid material chamber being lowered hydraulically, whereby a ring gap opens, through which the sediments can be pushed out at full rotational speed. The self-cleaning disc separators (high speed separators) are thus suitable for medium solid material contents in the suspension being fed in (up to ca. 10% by volume as a guideline).
A self-cleaning (self-discharging or automatic) disc separator is, as a rule, also CIP capable. The automatic CIP cleaning is integrated by the controller. As a rule, the volume of the solid material discharge during an emptying cycle can be set. In the case of a complete emptying of the drum, one also speaks of a full emptying or total emptying; for a smaller emptying one then speaks of a partial emptying.
Solid Bowl Disc Separator
With respect to the discharge of the solid material the solid wall disc separator operates discontinuously, i.e. the high speed separator must first of all be stopped in order to remove the spun off sediments manually. The solid wall separators are thus, with respect to purification, only suitable for low solid material contents in the suspension being fed in (up to ca. 1% by volume as a guideline) or for the separation of two liquids of different density.
In the case of the nozzle the sediments spun off in the centrifugal field are continuously discharged by nozzles installed in the drum. Nozzle separators are suitable for a solid material content in the in-feed of up to 25% by volume (rough guideline).
The nozzle separator is used, above all, if a high solid material thickening with, at the same time, optimal purification is required, or, if fluids with a high solid material content are to separated at a high throughput.
A nozzle separator can be supplied with a purification drum or a separator drum. This results in new areas of application as a purifier or concentrator (e.g. in the manufacture of antibiotics, china clay, starches, yeasts, quark etc.) and as a separator (e.g. extracting oil from oil sand, oil from oil shale etc.).
Nozzle Separator Drum
The liquid to be separated is fed into the drum centrally, while passing the disc packet the solid material particles are separated from the fluid and are guided outwards into the so-called sludge chamber in the drum. There the solid materials are continuously discharged out of the drum. At this point it must be mentioned that, depending on the concrete application, different nozzles are used, that are placed in different positions in the drum (e.g. in the wall of the drum or in the bottom of the drum).
Depending of the problem, nozzle separators can also be equipped with a concentrate recirculation or a washing device.
Furthermore, nozzle separators (depending on the application) can, in addition to the nozzle discharge, also be equipped with a system for periodic solid material ejection (as on self-cleaning disc separators).
Thus there is a “tailor-made” nozzle drum type for every application.
As a rule the nozzle separator is CIP capable.
Nozzle separator drive
With regards to the drive, there are different versions of nozzle separators. The drum can be driven via helical gears as well as by a belt.
The lubrication of all bearings on the drum spindle and the gearbox is done automatically from a central oil sump. Oil level / lubricating oil circulation can be checked in an inspection glass.