FLOTTWEG DISC STACK CENTRIFUGES
Disc stack centrifuges with self-cleaning bowl for solid-liquid separation are essential in many mechanical separation processes for solid-liquid separation.
The rotation speed of disc stack centrifuges is much higher than most other centrifuges in industry. The centrifugal force in a disc stack bowl is apparently stronger than for e.g. in a decanter. Hence disc stack centrifuges are predestined for processes which require high separation efficiency or the separation of micro particles. Even mixtures of liquid phases with very small difference in density can be separated.
As well as FLOTTWEG DECANTERS, also FLOTTWEG DISC STACK CENTRIFUGES offer the right solution for each customer – whether as single machines or as systems together with DECANTERS, TRICANTERS and BELT PRESSES.
Features of the FLOTTWEG DISC STACK CENTRIFUGE
The required drive power is transmitted directly to the bowl shaft using a standard three- phase AC motor with frequency drive control via a V-ripped or flat belt. The motor is controlled by a frequency drive enabling a smooth acceleration and limiting the inrush current. Furthermore, there is the possibility to vary the bowl speed. Compared with other drive systems, the FLOTTWEG drive offers lower maintenance and increased efficiency.
Materials of construction
All product-wetted parts are made of special stainless steels. Depending on the requirements, the components of the bowl are made of Cr-Ni-Steel or duplex alloys. By default, the sealing materials are made of perbunan (NBR) and polyamide. Other materials such as PEEK, Viton, EPDM, or FKM are available.
The bearings are lubricated using an internal oil lubrication system. Oil level and flow are controlled by the control system (AC1500, 2000, 2500). An oil pump provides appropriate proportioning of the lubricating oil.
The hydrohermetic seal option enables hermetic feed of the product (clarifier version). Oxygen pick-up, foaming, or gas leakage is avoided. The hydrohermetic seal consists of a stationary disc above the impeller. The disc is dipped into the fluid sealing the product from the environment. The system is quite similar to a siphon.
All FLOTTWEG SEPARATORS are in compliance with the regulations of 94/9/EG (ATEX95). They are suitable for use in explosion hazardous areas.
Inert gas purge unit
Inert gas purge units are necessary for the production of products whose vapors may contaminate the atmosphere or to prevent contact of the product with the atmosphere (oxidation). If centrifuges are used to process media whose vapors mixed with aerial oxygen generate an explosive mixture, the risk of explosion has to be eliminated by replacing air with an inert gas. Usually this operation is done using pure nitrogen. Centrifuges and system parts used for the processing of such materials have to be gastight to prevent the exit of vapors into the atmosphere as well as to avoid the entry of air into the system. Inert gas is injected into several parts of the centrifuge in order to provide optimal purging and inert gas blanketing inside the centrifuge.
Inert gas purge units are typically used in chemical, pharmaceutical, or the mineral oil industries. It is used for all systems which process highly flammable organic solvents or hazardous volatile components.
Inert gas units prevent the oxidation of products in the food and beverage industry as well as in the edible oil industry.
FLOTTWEG SEPARATORS are designed according to requirements of “Hygienic design”. They can easily be integrated into an automatic CIP-system.
All centrifuge functions and components are monitored and operated by a programmable logic controller (PLC). The control cabinet includes:
- Motor protectors and ramp-up control system using frequency drive
- Timer for automatic solid discharge
- Solid discharge controlled by turbidimeter (option)
- Control of all components of the disc stack centrifuge and (optional) secondary systems
- All necessary touch and operating controls