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Reverse Osmosis

Reverse Osmosis

Reverse Osmosis


We are designing a processes of Reverse Osmosis (RO) to spererate milk solids and water.  

This process must be able to seperate 50% of water from milk.  I am having trouble finding the calculations for the size, temperature, pressure differences, etc.  

Can anyone here help me with giving me some calculations.

Thanks! smile

RE: Reverse Osmosis

I'm guessing you wouldn't use RO for that.  

I'd start with looking at the size of the colloidal partical you want to remove and then select a membrane.

Possibly UF followed by RO?

RE: Reverse Osmosis

Thanks for the tip. I thought of doing a Centrifugation of milk then proceeding it to RO. any thoughts on that?

I'm having a bit of trouble with the calculations aswell

RE: Reverse Osmosis

What do you want to use the permeate for? And were can you send the reject?

1.  Call someone who has experience designing these systems.  An off the self R.O. system from Siemens/GE/Aquatech can be headaches down the road.  In dairy plants organics will be your main problem and you will be cleaning all the time if not designed properly.  I would recommend calling Ken Pandya from AWTS.  He's a strong engineer.

2.  Consult the Dow R.O. manual chapter 3. p. 70 - 99.

3.  Obtain a particle analysis down to .2 micron, a water analysis (most COW water/dairy water is low in hardness), several SDI (15 min) test.

4.  Then determine your flow rates.  Also design for low flux rates of 10 gfd and plan for high feed spacer membranes.

If you don't understand these terms; you probably shouldn't be designing the system.

RE: Reverse Osmosis

Hello madchemist11.
The RO of milk is a common application, and has been applied for many years in the dairy industry. One needs to use the appropriate system design as well as the right sanitary membrane design.

Please bear in mind that the membranes need to be cleaned every 10 hours, and that the life of the membranes are about 2 years. The best way to run this is cold.

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