TWINCONE decanter centrifuge
TWINCONE decanter centrifuge
Optimum washing in the decanter
The SIEBTECHNIK TWINCONE decanter centrifuge is a decanter centrifuge with a second bowl cone fitted downstream.
The solid matter is separated and concentrated by sedimentation in the first bowl cone. The second bowl cone has a larger diameter, so a lower head of solid matter forms ahead of the worm channel. On this second bowl cone the product can be washed and the washing liquid drained off separately from the mother liquor.
Because of the larger diameter great centrifugal forces are exerted on the second bowl cone, and these help dewatering.
All SIEBTECHNIK TWINCONE decanters are adapted individually to the product conditions and system requirements.
Operational behaviour and mechanical characteristics
The suspension fed in through the inlet pipe is accelerated in a relatively small bowl diameter designed to suit clarification requirements.
The solid matter that has settled in the clarification bowl is pre-thickened by means of a short cone. Here the filling volume of the bowl and therefore the length of the dewatering section can be steplessly adjusted by means of a weir plate.
The pre-thickened solid matter is discharged over the discharge rim at the end of the clarification bowl and into a considerably larger dimensioned drying cone downstream.
Here the solids cake is broken up and redistributed with a lower head of material ahead of the worm channel to match the larger cone volume and accordingly smaller filling volumes between channels.
At the same time the larger diameter of the drying cone guarantees high xg numbers at relatively low rotor speeds. The residual liquid is drained off through a separate liquid outlet in the centrifuge housing.
The solid matter carry-overs in the redewatering centrate are small and because of recirculation into the centrifuge are not to be rated as a loss or a load.
Product washing is also possible with the downstream drying cone, the wash fluid then being drained off separately from the mother liquor.
Drives for centrifuges
The solution to a separation task depends very decisively on the centrifuge drive. The centrifugal force required for solid-liquid separation is determined by the bowl or screen speed. To achieve the right speed for optimum separating results, it is frequently necessary to keep the speeds variable. The drive control needed for this is designed by our specialists specifically to fit your application.
Furthermore, on screen worm centrifuges and in decanters the speed differential between the solid-conveying worm and the bowl is decisive. It determines the time which the solid spends in the centrifuge and so the quality of the drying. The correct speed differential for your separation task is determined by the correct choice of gear unit. The speed differential here may be constant, but may also be variable. In the latter case the back-drive, where the otherwise fixed gear input shaft is also driven, is used. If the worm speed is required to be kept completely independent of the drum speed, hydraulic drives (viscotherms) or two-stage gear units with an upstream differential planetary stage are used.
To guarantee the operational reliability of your centrifuge, the drive system is continuously monitored. Excessive speeds, overcurrent and slip are identified and reported to the machine control system and there processed.
Only a drive system specially designed for your separating task will give optimum separating results.
Explosion protection / inertising
Inertisation of our machines and systems may be necessary for various reasons. In many industrial processes it is necessary for safety reasons to reliably prevent the build-up of an explosive atmosphere through dust or gases (ATEX).
It may also be necessary to seal and overlay the product spaces with inert gas, e.g. nitrogen (N2) or carbon dioxide (CO2), to prevent oxidation and maintain product quality.
Use SIEBTECHNIK specialialists’ many decades of experience in all areas of industry to help seal and inertise the process spaces in your centrifuges.
We will be pleased to work with our customers to draw up an inertising concept for the integration of our machines into existing or scheduled plant systems.
Hygienic Design / CIP
The name SIEBTECHNIK is inseparably associated with dewatering tasks to meet the most stringent hygiene requirements. The separation of batter from frying oil at temperatures of approx. 200°C with the SHORTBOWL decanter centrifuge, the centrifuging of lactose crystals with the SHORTBOWL decanter centrifuge and the CONTURBEX screen worm centrifuge for the manufacture of baby food or the manufacture of extremely pure inorganic salts with our CONTURBEX and pusher centrifuges are some examples. Design features for this are the technical separation of the drive and processing sections of the centrifuge and highly developed sealing systems that are easy to clean by CIP.
For the optimisation of centrifuges in the hygiene sector and/or in areas where e.g. cross-contamination has to be prevented by CIP we use riboflavin tests to examine and optimise cleaning results.
Our self-developed and USDA-certified CIP nozzles, self-developed hygienic screw connections, special hygiene surfaces or our highly developed USDA-conformant sealing technology make many dewatering tasks possible only with our centriguges.
Our reliable service enables optimum operation of your machines and systems. We offer energy optimisation, machine monitoring, an on-site maintenance and & repair service, OEM spare parts, damage cause analysis, maintenance & repair kits, stock inventory analysis, machine history management, personal technical consultation, training & workshops, 24 hr service, retrofitting & upgrades and used & loan machines.
Ask us, we’re there for you.
SIEBTECHNIK TEMA has consistently developed itself into one of the world’s most innovative manufacturer of continuous centrifuges and suppliers of system solutions in the field of mechanical and thermal solid-liquid separation since the early 1940s. SIEBTECHNIK/TEMA is your reliable partner for customer-focused, custom-built machines and system solutions.
SIEBTECHNIK TEMA centrifuge and drier systems offer you the latest technology, customer- and product-specific special fittings and individual consultation at the pre-sales stage and reliable support in the after-sales process. For mechanical liquid separation continuously operating centrifuges are often the technically and economically best solution. They separate large volumes in closed housings with little space requirement and low energy and time costs. Also drying on the fluidised bed with fluidised bed driers and coolers has established itself in numerous branches of industry and applications.
- Continuous operation
- Washing with separate separation of mother liquor and washing liquid
- Wide range of applications in all areas of industry
- Flexible drive concept
- High machine availability
- Minimum maintenance
- Long service life
- Optimum adjustment of clarification and dewatering