which membrane ?

[Brent]

Over the weekend I became the proud owner of a new (new as in I never had it before ) Airablo 180 RO system.

The system has 2 Hydranautics 4" x 40" membranes and from the date of manufacture on the system, I would say they have had 4 seasons on them.

I have no way to test them but the former owner said he had good performance from them.

The system tops out at 300 PSI ... should I be thinking about changing to a set of Filmtecs or ....??????

[Russell Lampron]

As long as the Hydranautic membranes aren't clogged and don't pass sugar use them until they need to be replaced. When they do need to be replaced you could change them over to Film Techs if you wanted.

[Justin Turco]

Russ, The film techs are pretty good? How are they diferent?

I guess diferent membrains are known for diferent characteristics?

Justin

[Brent]

I was reading on the Dow / Filmtec site this afternoon and they do some comparison between their own different membranes.

comments like much slower than our xyz but better rejection of trace minerals

And so I start wondering what those trace minerals are and what, if anything, they contribute to the differences in flavors we see.

[Acer]

http://www.dow.com/PublishedLiterature/dh_003f/0901b8038003fd0e.pdf?filepath=liquidseps/pdfs/noreg/609-00513.pdf&fromPage=GetDoc

[Russell Lampron]

Go to www.formembranes.com for answers to your membrane questions. They have listings for all brands, types and sizes of membranes. They also have price lists.

[Brent]

Russ
I checked the link you gave at foremembranes.com and could not see the PVD-1 membrane that is in the Airablo.

So I sent them and email and Joe responded
quote
"
I used to sell the PVD1 (8 x 40) at a slight markup. Then Hydranautics
gave an exclusive to Dominion Grimm in Canada, where you can but it for an arm
and a leg, and your first born.

So after protesting their disloyalty (since I am a large Hydranautics
distributor) I switch all my customers over to FilmTec NF270-400. It is
dimensionally identical and performs as well or better, at $777.00 each."
unquote.

[Russell Lampron]

Joe also gave me the low down on the Mark 1 membrane. I asked him why they don't make a 4" version. He told me this was straight from the president of Dow. The Mark 1 is an NF90 400 membrane with different end caps on it. He also told me that he has the plugs and fittings in stock to make an NF90 400 fit where a Mark 1 came out of.

This goes against what the link that Acer posted says but who are you going to believe. His NF90 400 is $781 compared to $1300 plus for a Mark 1 from a maple supplier.

I am very happy with the performance of the NF90 4040 that came with my RO but I am also pleased with the performance of the used XLE 4040 membrane that a friend gave to me to try.

The NF270 series are the fastest membranes that they have but will pass some sugar.

[Brent]

Russ

looks like we've got pretty nearly the same rigs.
similar RO machines and same size evaporators.

how many taps you got going ?
Do you find the RO keeps up with the evaporator ?
If you were buying new membranes today, which would you pick ?

[Mark]

I have bought a bunch of membranes from Joe and you can't find a nicer guy or price. Prefilters also.

[Brent]

Next question, since Mark reminded me that I meant to ask,

do any of you guys put finer pre-filters on the systems. I think mine has a 10 micron in it now and of course that is the "Nominal" rating which means it catches 60% of the 10 micron stuff.

The microbes we want to catch are about 1 micron.

[Russell Lampron]

Brent I had 538 taps this year. I increased the number of taps that I had on vacuum from 250 to 461. I used to have over 600 taps on 2 sites but now have all of them on my own property. The reduced number of taps out performed the old taps because of the vacuum. I collected almost 10,000 gallons of sap this year more than double what I got in 2008.

When I was concentrating in a single pass the RO would put out enough concentrate at 3/4 gallon per minute to keep up with the evaporator. I have since started recirculating my sap and giving the RO a head start. I was splitting all of my wood into kindling size pieces and got my evaporation rate into the mid 40's outboiling the RO. I added a blower to the evaporator late this season too. Now I don't have to split the wood so fine anymore and the evaporation rate is through the roof. I now need a 600gph RO to go back to the single pass method.

[Russell Lampron]

I use 5 micron pre filters and wrap those with a cloth to catch the slime. I don't know how many microns the cloth wraps are but I got them with the RO and use them per Lapierres instructions.

[Brent]

So far all my RO playing has been with the GE Merlin units and that taught me that pre-filtering was pretty important. It would seem to me that fine pre-filtering might extend the hours between rinses and washes, and the finer the pre-filter the better.
So somewhere there is a trade off on filter cost against time lost in rinsing and or complete wash.

I put a 1 micron nominal filter on the Merlins and after running for 2 boils, which included going all night on 1 tote (275 gallons ) I could see the filter going rusty / orange color and the pressure would drop about 2 or 3 psi going through it. That's when I would change it. But that was $ 18 a pop every other day.

When you did the cloth wrap, how often did you have to change the filter.
I have not checked the filter on mine to compare to standard sizes but I am guessing it will be aobut 2" diameter and about 20 - 24" long.

[Russell Lampron]

I forgot to add that I would probably buy another NF90 when it is time to replace it. The XLE is a low pressure membrane and my RO is capable of running at just under 500psi. I run it around 300psi now and that is 3x higher than the recommended working pressure of the XLE membrane. The XLE has a 600psi max pressure but I don't feel comfortable going over 300psi with it. The NF90 can be run at 500psi all season if need be. The XLE is tape wrapped while the NF90 is fiberglass wrapped.

[Brent]

The Airablo only goes to 300 psi and Charlie told me only ran it at 250.
500 to 600 lbs starts to sound like a potential bomb, and sugar shacks are small.

[Daren]

I have been reading this thread as I would love to get into a RO in the next three years. I have to admit that the costs are very scary.....especially on such as small scale as I would be running. I do however need to ease up on the wood my evap wants to eat and the reduction in boiling time is priceless with the "new family". Heck might even be able to visit a few friends while they boil and still triple my own output. With that said....what is the life expectancy of the membranes? At $800 a pop, those extra expenses would really jack the overall price of an RO up.....

[Russell Lampron]

Brent Lapierre has the 20" 5 micron pre filters for less than $5 each. I change the cloth wrap every time I use the RO and I used 6 pre filters the entire season.

Daren those prices are for 8" membranes. A small RO like mine uses one 4" membrane and I can buy a new NF90 4040 for $300. The XLE membrane is closer to $200. With proper use and cleaning a membrane will last for many years. You can send them to the manufacturers and have them cleaned and tested too. Lapierre and Maplepro both do it.

[maple flats]

As I was inquiring about an RO, my dealer said the life expectancy drops fast as you go higher sugar %. Don't quote me but the idea was at 6% a membrane lasts about 14 years, at 8% about 10-11 years, at 10% about 7-8 years up to 20-22% for 1 or 2 seasons. They ran their RO in 08 at 7% and went to 8% for 09. She thought this would cost them a couple of years life expectancy. Any one out there who can support or dis prove these #'s?

[Brent]

You gotta luv the nerds that write instructions for machines that they built and could run in their sleep.

I got home tonight and want to run wash cycle with the lye, ( sodium hydroxide ) The instructions call for 4 ounces per membrane. But everything else in the book is written for a machine with a single 8" membrane and mine has two 4" membranes. Everyone knows, I hope, the two 4" diameters don't make one 8". So I guess and dump some in.

Then they say to run it until the temperature gets up to 115 degrees F. Run what. The feed pump ? or both pumps ?

Then after the wash cycle they say to run acid through it. What acid ?
and what Ph ?

The unit is the Airablo 160 -180 GPH. Can anyone shed some light on this for me please ?

[Russell Lampron]

Brent disregard the oz per membrane instructions on the RO soap. Mix it with your wash water to a ph of 11.

My RO is a Lapierre and I only run the feed pump. The circulation pump on the membrane housing automatically starts when the feed pump pressure is over 20psi. If your circulation pumps don't run without the high pressure pump on you will have to run that one too. If you do have to run the high pressure pump keep the pressure very low.

For the acid wash mix it to a ph of 2. Do another Sodium Hydroxide wash after the acid wash rinsing the membranes good between all washes.

[Daren]

Hey...that sounds better than I thought it would. $300 every 10 or more years is WAY worth it! Any other good news Russ and Dave? You are on a roll in my book right now!