RO/DI unit pressure

[StirCrazy]

The R/O's being sold by kent, reefpur ect.. are all based off a domestic membraine. the intended use is for drinking water in your home. this is oposed to comercial models (like the kind we use on the ships) that make 230gph of ultra pure water. the main differnce being that a domestic unit will run off of standard house hold water pressures 40 to 80 psi. acording to AMI, there resadentual membrains are recomended to be operated at
Maximum Operating Pressure 125 psi (0.86 MPa)
Maximum Feed Flow Rate 2 gpm
Maximum Operating Temperature 113°F (45°C)

whare the RECOMMENDED OPERATION CONDITIONS for there comercial thin film membraine are
maximum operation pressure 300 psi
maximum feed flow rate - 2" elements: 3 gpm
2.5" elements: 6 gpm
4" elements: 17 gpm
maximum operating temperature 113° F (45° C)

this is the filmtec/dow specs for resadentual thin film membrains (probably the most commen one)
Operating Limits
Maximum Operating Pressure 125 psi (0.86 MPa)
Maximum Feed Flow rate 2 gpm (7.5 lpm)
Minimum Concentrate Flow Rate 4 x permeate flow

there comercial model like the ASI is a 300psi one. another thing that seams commen is domestic tap water membrains seam to be 98% rejection, whare the comercial ones are mostly 99%

if you want to see the kind I work with on a daily basis HERE is a link to the specs.. I am curently working at setting up a fully working trainer at the school (when i go back to work that is) so I will be able to make about a ton of water / hour with a 99.6% rejection rate.

I hope this answered yyour question Jamie

Steve