In this project, bentonite suspensions of different origins are recycled. For this purpose, the bentonite suspension is first buffered in a dosing buffer and then continuously fed into a 2-chamber recycling plant. While the mineral components >250 μm are discharged, the resulting process water with mineral components ≤250 μm is fed to a chamber filter press.
Bentonite suspension on deliveryBeginning situation
Material on delivery
Material Bentonite suspension
Delivery Suction truck (20 m³)
Density 1.22 kg/l
TS-content 30.0 %
Quantity max. 390 t/day
Material after recycling process
Material Process water
Density 1.07 kg/l
TS-content 10.3 %
Objective
The objective of the recycling system is to reduce disposal costs. This is done through the following steps:
- Reduction of the disposal volume through separation and discharge of the water contained (filtrate)
- Reduction of the disposal costs by generating a puncture-proof filter cake from the mineral components
Filtration process
The filtration process of the process water includes the following steps:
- Precipitation*
- Flocculation*
- Filtration
*The selection of the optimal chemical products as well as the determination of the dosage and the concentration is done in a preliminary test.
Process water light-grainyPrecipitation
During this process, the bentonite particles contained in the suspension are destabilised.
Product Polyl solution
Manufacturer SEPAR-CHEMIE
Concentration undiluted
Process water flocculatedFlockung
Nach der Fällung wird das Prozesswasser geflockt.
Dabei werden die suspendierten Bentonitpartikel zur besseren Filtration zu größeren Flocken vereint.
Produkt Wasserlösliches Polymer
Hersteller SEPAR-CHEMIE
Konzentration verdünnte Lösung
Filtration with chamber filter press
The next step is the filtration of the flocculated process water with a chamber filter press.
BIBKO® Filterpress
Membrane filter press as an alternative to the conventional chamber filter press
Compared to the conventional chamber filter press, membrane filter presses offer the possibility to further reduce the liquid remaining in the filter cake after the filtration process. This increases the dry matter content. For this purpose, the filter cloths are pressurised with air after the filtration process. The filter cloth is pressed against the filter cake, so that the filter cake is additionally dewatered.
