Membrane Testing

[Amber Gold]

The RO machine I bought last season came with a used membrane (Mark 1) and was told it was tested and didn't pass sugar. After calc'ing how much syrup I should've made vs. what I made, I came up short. I tested the perm. during the season and didn't find it passing. Just to be safe, I want to get the membrane tested to confirm it doesn't pass. Where can I get the membrane tested...preferably from someone who doesn't sell membranes, so there's no conflict of interest? How much does it cost?

Is there a way I can do my own testing in the off season?

Thanks

[PerryFamily]

I am under the impression that it costs a couple hundred bucks to clean and test. Not sure if that includes shipping. Most likely not.

The used machine I bought last yr had a 4great yr old membrane (270) at 6000the taps per yr plus my 1100 last yr. My permeate tested 0 with the hydro but my suspicion is it was passing and was dirty.

Instead of spending a couple hundred, i am going to get a new one.

My opinion

[delivron]

Lapierre will wash and test approximately $189.00 just take it to Orleans, VT store. Washing will assure you membrane is working at peek efficiency. You should always have the membrane washed d annually. Keep a performance record daily. There is a good chart in the back of the Lapierre manual. It can be downloaded from their web site. If the membrane was previously cared for it should have another 2 to 3 years left in it. Lapierre runs a solution through the membrane if it passes to the permeate side of the RO the membrane is a failed membrane. IE you are losing sugar to the permeate. Usually a factory wash will restore a membrane to about 8 85 to 95 of peak performance.

[maple2]

we used to mix up a batch of food coloring and water and run it through the machine

[wiam]

Hydrometers are not real accurate close to zero. If you boil down some permeate and test that you can check it. I have also heard of someone that concentrated permeate and then tested that. It would have to be right after a wash.
I think H2O is cheaper to wash

[PerryFamily]

In another thread, I mentioned that the vessel on my RO smells. It was determined it is bacteria. I am not worried about the membrane since I am going to get a new one. But how about cleaning the inside plumbing of the machine?

My thinking is once it is in its permanent location, discarding the membrane and running chlorinated water through the machine for a bit. Maybe even soap. Then flushing with fresh water.

Any idea if you can run the machine with the membrane removed?

I think it will clean it just wondering about the membrane.

After this season I will remove the membrane promptly and have it cleaned.

Any advice is appreciated

[TunbridgeDave]

I would do the "concentrate the permeate" method. I use spring water to make permeate in the off season if necessary. Then I took 20 parts perm and boiled it down to 1 and tested with the hydrometer. Or buy a refactometer. That would be cheaper then having the membrane tested and is very accurate.

[DrTimPerkins]

....running chlorinated water through the machine for a bit. Maybe even soap. Then flushing with fresh water.

Don't use chlorinated water if your membrane is in the machine. Very bad for the membrane. Check with the manufacturer of your unit for specific recommended practices. There are some important differences that shouldn't be ignored.

[PerryFamily]

Dr Tim
I was going to discard the existing membrane and run it without the membrane in it with chlorinated water to clean out the vessel and piping. Then flush with clean water and drain the unit. Once I get the new membrane install it and go for it.

[DrTimPerkins]

Dr Tim
I was going to discard the existing membrane and run it without the membrane in it with chlorinated water to clean out the vessel and piping. Then flush with clean water and drain the unit. Once I get the new membrane install it and go for it.

That's probably OK, but don't overdo the chlorine, and rinse and drain fairly quickly afterward.

[PerryFamily]

Thanks Dr. TIM

[Amber Gold]

Boiling down permeate during the off-season wouldn't help now. I did this during the season, but didn't start till about halfway through and I think it came up clean each time I tried.

One thing Dow told me is to do the perm. test shortly after the RO starts running before the membrane starts to biofoul. The reason is the membrane is less likely to pass sugar once a biofilm starts building on it...makes sense, but I didn't know about this until after the season.

[TheMapleMoose]

Just a thought but when you finished concentrating for the day did you chase the sugar out of the machine before rinsing it? If not every day you ran you dumped sugar down the drain.

[Amber Gold]

Sure did.

Didn't know mapletrader required at least 10 characters when posting a response. My reply above was too short...

[maple flats]

Sure did.

Didn't know mapletrader required at least 10 characters when posting a response. My reply above was too short...
Being long winded I didn't know that for a couple of years.

[maplwrks]

I used to be very religious about sending my membranes back for cleaning and testing. The last time I sent them back, it cost me $375. Roughly $185 a membrane. I no longer send them back now, I clean the snot out of them at the end of the year, put the pickle juice to them and into the canisters they go. I'll save that $$$ and buy a new membrane every couple years instead. At $800 a membrane, it's not worth spending the $$ to clean them.

[Maplewalnut]

I used to be very religious about sending my membranes back for cleaning and testing. The last time I sent them back, it cost me $375. Roughly $185 a membrane. I no longer send them back now, I clean the snot out of them at the end of the year, put the pickle juice to them and into the canisters they go. I'll save that $$$ and buy a new membrane every couple years instead. At $800 a membrane, it's not worth spending the $$ to clean them.

Mike- Thats just where I am it in my thinking. I took mine this year to get professionally cleaned just because I snotted them up the end of last season without a great post season wash. Then forgot about them and left them in the vessel for two months before removing them from RO. I am figuring 6 years per membrane life expectancy with a professional clean (maybe) about half way. With new technology.... nf90s arent as good as nf270s which may or may not be as good as 4040s and it probably pays to get new every few years anyway.

Mike