Best results cleaning NF270

[trackerguy]

OK...looks like it's time to clean the NF270-4040.

Instructions say:

77F pH12
95F pH11
113f pH10

max temp 113F

So... what combination works best? the pH's are a full point lower than the XLE4040 and the max temp is 10 degrees lower also.

Using the same Airablo soap as I did for the XLE, have thermometer and pH paper.

Russ, do you have some experience in this area??

-Wes

[royalmaple]

I've been having great results washing mine this year as follows:

Rinse machine after concentrating to get sugar out
recirculate wash tank till 43 C
Let is soak all night
next morning bring same wash water back up to 43 C
then rinse with perm. With (2) NF270-4040 I rinse with 400-600 gallons of perm since I have 1500 on hand seems like all the time.

Works for me for sure. Last night I was putting out 5 gpm perm out of the hole at 200 psi and concentrate valve was wide open recirculating

[sapmaple]

I just got a NF 270 and was told to bring wash tank up to ph of 9.5 then rinse with prem. So Matt do you use any soap??? are you concerned with ph???
by the way I love the flow rates of the NF 270 compared to the Mark I I was using before

[royalmaple]

Yeah, I use the regular soap from Lapierre, it is 10-11 ph.

I have / had a ph meter. Lent it out and still have yet to get it back.

I don't use a ton of soap, maybe a shot glass full in 15 or so gallon wash tank.

The soap is buffered so you only need the amount to maintain the ph, which could be a shotglass, so even if you put in the whole plastic tub it won't get higher ph.

Those"specially formulated" maple membranes with all the magic inside are POS. If you want flow rates at low pressure and not passing sugar buy a nf270. I had two NF90's which are the same as the Magic Membranes and couldn't get any flow rates, now with two new 270's water is leaving in a hurry. same machine and much lower pressure and works like a swiss watch.

[trackerguy]

Good info Matt. Last night I brought it up to 95 degrees (35C) and added about 1 tablespoon Airablo soap into the 5 gallon bucket. Ph came up to nearly 12, well past the 11 I was shooting for. Quiclky added a little water, ended up cleaning at about 11.5 and 95F. Water turned very light green, so at least they're clean. Sounds like I should make a quick run up to Swanton and get some of that buffered soap that holds PH under 11. Hopefully the membranes are OK, will find out when I run the next batch.

[Russell Lampron]

The higher ph shouldn't hurt the membrane. If you read the instructions on the container of Lapierre soap you would be putting half of the container into the wash tank to do a wash. It only takes a couple of tablespoons to get it to ph 11.

My wash water gets heated as the RO runs through the wash cycle and shuts itself off at 43c which is about 113f. I do one wash cycle with soap then rince with about 300 gallons of permeate. I haven't used any membrane soap other than the Lapierre soap.

Like Matts my RO came to life when I switched to the NF 270 membrane. Much higher flow rates at much lower pressure and no sugar passage if I don't slow down the concentrate flow at higher concentration levels. I normally concentrate to 16% plus by recirculating my sap.

[royalmaple]

I think you'll find the soap does not actually "activate" until somewhere around 105-110F, so you need to get to that point to do much of anything.

[danno]

Does continuing to re-circ your wash get your wash solution hot enough, or is anybody using a seperate heating element?

[Russell Lampron]

My RO heats the water enough but others don't. If you have a brand that doesn't you will have to heat the water.

[maplwrks]

Matt---How high of a concentration are you running through your 270?

[PATheron]

Mike- Im running the 270's in my seprotech. Im recircing with both machines till I get up around 15%. Thats what I kind of shoot for becouse thats what dad likes in the evap. I have taken batches to 18. Recirced them the whole way. Never really pinched it down much under 5 gallons a minute on the concentrate. Been watching very carefully for sugar passage and havent been able to read anything yet on my refractometer. I think it must be becouse I never pinch it down. Thats my thought anyway. Real happy with them the way Im doing things so far. Theron

[royalmaple]

Mike -

I've gone up to 14% only because I haven't had enough sap to go much higher and still have 200 gallons so I can boil for an hour or so.

When you start with 1% you don't have much to work with.

[maplwrks]

I've always been told that they will pass sugar if run to high concentrations. This year, I've been running the concentrate flow real high trying to keep pressures low. When I push up to 20%+, I still get 450 psi on the membranes, I would like to try some 270s to try to keep pressure down if I can do it without passing sugar. I would like to hear from someome that pushes these membranes to see if they are for me. I know from the flow rates I'm hearing, they could work for me!!

[royalmaple]

Mike-

When I was at Theron's in early Feb we hooked up his new RO with two 8" NF270's and he like a hawk watched the permeate. Just about wore a trench in his concrete slab from the ro, to the tanks out behind the sugarhouse.

We went up to 18% that night and no trace of sugar being passed. I think the trick is the pressure.

For example, I am able to recirculate at 200-250 psi and get 4.5-5 gallons permeate out of the hole on fresh sap with my concentrate valve wide open, no restriction on it at all. It does certainly slow down as the mix gets higher but I am dumping some serious amounts of water in a hurry. And that is with 2 4" membranes. Even when it is up to 10%, I'm still in the 180-200 gph on the permeate side and concentrate valve never gets touched, I leave it wide open. I typically shoot for 200psi and leave it right there.

I haven't been able to measure any sugar in the perm with my digital hannah refractometer.

[maplwrks]

Thanks Matt! I may need to give couple 270s a try!

[Thompson's Tree Farm]

You guys have definitely got me thinking....And the wife says we need another RO. Might get some sleep next year...nah, just tap more:D

[Russell Lampron]

Mike what Theron and Matt are telling you is what I am seeing here too. I was up to 22% once and still no sugar in the permeate. The pressure was at 200 and the concentrate flow was cranked wide open. I have done some experimenting and when I "pinch" the concentrate flow as Theron says I will see some sugar in the permeate when I am up in the teens. As soon as I open the concentrate valve back up the sugar in the permeate goes back to 0%. The trick is to keep the high pressure low and concentrate flow high. I start out at 250psi and back it down to 200 or less as the sap gets sweeter.

The NF270 has turned my little single 4" membrane RO into a permeate flowing monster. I am seeing much higher flow rates when the NF270 is dirty than what I saw when my NF90 was clean. The NF270 cleans up nice too it doesn't take much to get the flow back.

[trackerguy]

Filmtec nf270 cleaning bulletin says there is a 40% boost in flow after cleaning above pH9 due to membrane expansion, back to normal after 3 days. Hmmmm... wonder if there's some way to take advantage of that??

[Russell Lampron]

That explains why I got 1gpm more concentrate and permeate flow after I washed it the first time. It hasn't sat for 3 days without being used since. I don't know if that expansion is bad but it doesn't pass sugar so I don't think that it is falling apart.