DIY RO - Need suggestions and direction

What would be the theoretical concentration factor and flow of the two options:

1. 2x150 in parallel then 2x150 in series...

or

2. 4x150 is series

All assuming the 8852 pump with a 5 micron pre filter.

Thanks.

Bryan

Hey Bryan,

The 2x150gpd membranes will get you about 5gph on a single 50/50 pass (taking 2% sap to 4% sap, at 40 degrees fahrenheit). Series and parallel are going to give you virtually the same performance. The membranes will last longer in series and I would suggest plumbing in series. (The reason is that each membrane is subjected to a higher flow rate).

4 x 150gpd membranes in series should get you around 10gph on a single 50/50 pass (taking 2% sap to 4% sap, at 40 degrees fahrenheit). You could run a higher restriction with four membranes in series (like 75% permeate and 25% concentrate) and get a single pass concentration of 6 to 8% sugar (however the flow rate would be closer to 5gph).

You would be pretty close to the limit of an 8852 with 4 membranes (unless you use a low pressure feed pump or have a tank with head pressure). The 8855 is a better option and they aren't that much more expensive. You would want something close to a 400gpd rating once you get up to (or over) 4 150gpd membranes.

Hope this helps!

Carl
The RO Bucket LLC

Parallel will process the sap faster, but require recirculation and a close eye on regulator. As sap % builds you lose efficiency which is why you can do more in parallel. In series you'll pull less water out per minute but it will be a one shot deal. Pm me if youd like more info. Assuming you are building your own from the mattatuck madness plans? That's great info and easy to build saving you alot of money over the RO Bucket. I did that way 1st year and then expanded to a parallel-ish piping setup. I now have a 4x40 setup going.

Bigger membranes increase volume.