Need water sedimentation in separators

Good day everyone!
Trying to make CO2 total extracts from spices - coriander, black pepper, cardamom. Made some tests in lab unit, 5 liters extractor, 2*1 liters separators.
Different modes of extraction, from 150 to 300 bar, 40-60C. 50 l\hour
The question is with water.
As all of us know, water in raw materials hampers CO2 extraction, because SF CO2 could extract (dissolve) water even better and firstly, than desired es. oils and non-volatile oils from raw material (water content is 5-9% in spices)
We CAN NOT DRY our raw material, especially under high T, because our es. oils are evaporated with water as well.
Please, don't advise to make ordinary water distillation for es. oils, we'd like to obtain exactly SFE total extracts from spices (something like here http://www.flavex.com/en/naturextrakte/products/details/artikel/coriander-co2-to-extract-25-essent-oil/)
The problem is in low speed of extraction, and if water content increases, even for 1% (for ex., we had 6% water, than 7%) the speed is lowering dramatically. In separators we found small quantity of water (considering it's content in raw material and in cake after extraction), that is extracted. It seems like the water is extracted together with spices extract, small quantity is separated together with desired extract, but most of water is going together with CO2 from separators to condenser and again to cycle, again obstructing the process.
Is there a possibility to aid most of this water to settle down in separator? Some assemblies, traps?

Comments

  • Have you tried Freeze-Drying?

    I see you have raised your Extraction Vessel Temps to try to keep water out of the solution, is the water miscible in your extracts? Can you chill your extract after you collect it and pour off the water?

    Have you considered some kind of molecular sieve in your clean co2 stream to remove the moisture in solution?

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