GE Merlin membrane technology

[Brent]

During earlier dialog about the GE Merlin one of the members was explaining that membranes are really nanofilters. Today I discovered a more technical document that explains that the Merlin uses a new technology that GE claims is in fact is not a nanofilter membrane. In the document they do not explicitly say what it is, but I know that GE bought Xenon water treatment systems about 2 years ago and that they had a completely new membrane technology. We sold Xenon, in Oakville, Ontario some milling machines and they would not let our servicemen into certain areas of the plant. Top secret stuff.

I also know there was a big dust up between the a wing of the Canadian government and Xenon because that particular sector was part of our international disaster relief team "DART" for short and their specialty was a portable system to create safe drinking water. This system was dispatched to various areas effected by the big Christmas tsunami a few years ago. The issue was that Xenon would not reveal how they cleaned the membranes and insisted that the membranes be returned on an exchange basis. Will they ever tell me how to clean it. I doubt it.

Soooooo..... will we have any success cleaning them for use in maple syrup on a repeated basis ... who knows. I did two cleaning cycles on mine this year. One with simple dishwasher detergent. It did restore the flow rates temporarily. The second time I used sodium hydroxide and that also restored the flow rate. Did I do any damage??? Don't know. I will be putting one of them in use in our household water system, and will find a TDS meter to see what is going on. Beyond that, we'll have to wait until next year.

For bedtime reading, now that most of us can go to bed at normal times again
http://www.gewater.com/pdf/resdntl/home/merlin/1266624_Merlin_Application_Guide.pdf

[tyrod2]

Brent In your GE Merlin do you remove your carbon filter or leave it in place in the RO ? I can see one of theas RO in my future.I like reading your threads. Keep them comming Thank you tyrod2

[Brent]

HI

last year I left the pre-filters in place and that appears to be what caused such poor results last year. The residential version comes with carbon pre-filters and they plugged up badly. The commercial version comes with a sediment filter. Given that the microbes are about 1 micron, neither of the factory filters do anything.

This year put in a stardard sediment filter that takes standard 10" x 4" filters. TSC has 1 micron wound filters for $ 19. Cdn and they appear to have worked well. When the pressure drops 2 PSI across the filters, I change them. The filters that come out smell pretty foul and have changed color with the trapped microbes. This restores the flow through the Merlins.

I just did some new calculations on the pump output. "Maple Sapper" is also using the same pump and 2 Merlins and seems to be pleased and suggested the pump could support a 3rd and maybe even a 4th Merlin. The calcs I did seem to support that. That will be the focus next year. I am also playing with the idea of trying a 1 or 0.5 "absolute rated" filter that is available from McMaster-Carr. Still not sure is we really need that though.

Edit: I now leave the top stage of the Merlins empty. That is where the pre-filters sit.

[DanE.]

I'm very interested in building my own RO, Yesterday while researching, I found this document on particle sizes. look at the bottom of the page. this support your idea of filtering at a much smaller level before the RO.

http://www.advancedwaterfilters.com/reverse-osmosis-system.html

Dan...

[Brent]

Dan

Thanks for the link. Always glad to read more about RO's
the chart in the article may be accurate but some of the claims about filter canisters flooding basements are preposterous. With that kind of BS I would take everything else in the "advertisement" with a large grain of salt.

[Gary R]

Brent,

I believe in the past you spoke of possible adding a UV light and how higher sap temperature would allow for faster RO proccessing. You have the 1 micron filter now. What if you went through the .5 micron absolute instead, then heated the sap before it goes to the Merlin. You should capture all the microbes in the .5 filter. Therefore heating the sap and holding concentrate should not result in excessive microbe growth. Concentrate shouldn't spoil and syrup grade should be good. Sound good?

[Brent]

it sounds good until you see the price of a 0.5 abosolute filter. If I recall correctly about $ 170.00

There would be fewer microbes to worry about if the UV sterilizes them so the filters might last longer, but if they are dead, who cares.

So far this year I've brought in nearly 4000 US Gal of sap and put it all through the Merlins with a 1 micron nominal rated filter. Earlier in the season when the sap was cooler the filter lasted several days. With warmer temps now it seems to get a little plugged up and smells foul in 48 hours. The Merlins are still working the same as day 1 this season.
15 gallons of permeate and hour at 2 to 2.5% sugars
about 5 gallons per hour when the sugars get above 5%.

Got a load of 5.2 going through right now.

Back on the UV, if it kills / sterilizes the microbes the filters, any filter, should last longer because they will not be breeding within the filter as well as just fewer of them. So far the UV looks like it will be worth a try, along with putting one or two more Merlins on line.

As far a warming goes, the microbes apparently double in population in warm sap, every 15 minutes. So you could only warm the sap and push it straight into the evaporator. You couldn't recirculate like I do all night. But with the UV continuously running all night along with the Merlins, you could recirculate I think, .... I hope

EDIT: for anyone not following this two year long saga, the above rates are with 2 of the GE Merlins on line at once.

[Gary R]

Bummer about the price of the filter. We sell .2 micron absolute for about $90.
We're in the medical field and I figured our's were high priced.

[Brent]

what size is that filter ?

the ones I've used this year is the standard 10 x 4"

[maple sapper]

I have had great sucess with my stock sediment filter that came with my merlins. The filter is not a 1 micron but figured that something in front of the membranes is better than none. The truth will be told next season when i try to use it again. I may do like Brent and get a bag filter and keep top chamber open. That way I can swap out the bag a bit easier. I also have flushed my merlins after each use with tempered hot water at 100 deg f. and it seems to work well. I have not pushed as much sap as Brent this season but it would seem that if it was not going to work routinely, It would have happen after the third or fouth time. I managed to get a tank of approx 80 gals of 5.7% after running ro and kept adding to it to keep tank low with suger content till it was all in and let it run till it looked like it was pointless. I have managed to get my tank up to 6% at one point when I paid attention.

[Brent]

Good news. Glad it worked for you. I actually used a GE cartridge filter, with a 10" x 4" replaceable. The fitler press with the bag got relegated to the kitchen for canning

Next year I may put the bag filter in the sugar shack because a bag filter with a 1 micron absolute rating is only $ 18. vs the cartridge at about $ 170.

To cut your boiling time in half, this rig is a no brainer. I'm going to try adding one or two more to the system next year to get the concentration up to the 5% or more level with the quantities of sap we get. May even split the system and put one or two in line with the evap and run a preheat line through the hood of the the evap to wring out even more water, before going to boil.

May go the UV route which could let me warm it and store it a while before boiling and without spoiling.

[tyrod2]

Brent You lost me. Where do you put this bag filter to filter the sap?Thank you tyrod2

[Brent]

Sorry. If you think you got confused you should have seen what I did last year.

Here is what I put in this year.
http://products.geappliances.com/ApplProducts/Dispatcher?REQUEST=SPECPAGE&SKU=GXWH04F&SITEID=DER&TABID=2

You can get a less expensive one without the little timer thing on top.
It normally comes with something like a 10 micron filter, but the 10 x 4 fitler is an industry standard.
This link puts you in the middle of the McMaster Carr filter pages. Scan back and forth and you will see a lot of stuff and interesting comments about nominal micron ratings vs. absolute micron ratings.
http://www.mcmaster.com/#catalog/115/372/=19sp4a

It is a GE whole house filter. I got the 1 micron cartridges from TSC.

You can see the syrup filter on our web site under "making syrup" This one takes the the standard # 1 bags. I think it would do a great job pre-filtering the sap as well but getting it back and forth from the house to the sugar shack is a bit of an issue.

Good luck

[Greenthumb]

Brent is does your pump run on 220. that seems to be what most inverter pumps run at.

thanks. Back to plow 8 inches of snow in april and syrup season is over go figure

[Brent]

the pump can be either 110 or 220, mine is 110.
It is an inverter drive so it can be one or the other but is not field switchable.
Being inverter it is "soft" start so the inrush current on start is minimal compared to a standard motor.

[maple sapper]

Brent,

So, I come to terms that season is now over. What and how should the membranes be stored to be good for another season? I am assuming freezing them is not good. Refrigeration perhaps? Store units with water and pressure in them? Dont think you want them to dry out. Not sure got lots of ideas as you can see. We definitely got a good thing going with these units. Thanks to your work and our practice.

[Brent]

Gregg
Freezing and drying are definitely not the way to go. They ship them with some fluid in them to protect from freezing damage. You may have noticed the plastic bag had moisture in with each membrane.

Most other membranes are stored in glycerin / glycol, and I have some standing by. I have sent a message earlier today to GE support and got an automated answer. I told them we wanted to store them for 11 months. We'll see what they say.

I have put up a summary of my experience with them on our web site.

I would appreciate any additions or corrections that you could add.

[Brent]

There have been a few Traders ask about getting the same pump I have. I have confirmed the cost with our machine builder in Taiwan and we can offer the following.

Total cost $ 1,200 US$ including shipping to NE States by UPS standard service, prepaid US customs clearance, duty and insurance all included. $ 15.00 extra if shipped to a residential/farm address rather than a regular business. Delivery would about 90-100 days because I am basing the cost on packing the pumps with our next load of machines so they get here free.

Let me know by PM if any of those that enquired want to get on board.

[Brent]

Just got the following response from GE.

I guess the best thing to do is put both of them on line in the house

quote:

Brent,

In response to your question about storing your Merlin RO for 11 months. We do not recommend preserving the membranes and could not warranty the membranes after they have been preserved.

Thank You,


Lou Bennett
Tech Support
Pentair Water
262-518-4392
louis.bennett@pentair.com<mailto:louis.bennett@pentair.com (louis.bennett@pentair.com)>
________________________________
From: Technical Support, GE Water (GE Infra, Water, non-ge) [mailto:Gewater.Technicalsupport@ge.com]
Sent: Monday, April 06, 2009 4:00 PM
To: Bennett, Louis; Johnson, Howard
Subject: FW: Brent Roberts of located in Caledon, ON - CANADA has requested additional information, CaseID-8217821, CaseID-8217821

Hi guys- Would you please direct this inquiry to the right contact.

Thanks,
Clint

________________________________
From: Veltri, Eileen (GE Infra, Water)
Sent: Monday, April 06, 2009 3:10 PM
To: Technical Support, GE Water (GE Infra, Water, non-ge)
Subject: FW: Brent Roberts of located in Caledon, ON - CANADA has requested additional information, CaseID-8217821, CaseID-8217821

[Brent]

I got a further bit of info from GE about storage.

They ship the Merlins with a solution of sodium metabisulfite in them to inhibit microbe growth. They did not advise the concentration so I have asked about that. They say they have never had a request about preserving the systems before and I would have to say that they are not endorsing this.