Reverse Osmosis

[farmerEd]

Can someone give me a few quick tutorial on them? Don't have one, and don't need one yet, but looking down the road a bit.....

Using a specific example, if my sap takes exactly 40 gallons to make a gallon of syrup, what then is my sugar content % going in?

Now if I run those 40 gallons thru a RO machine, what is the sugar content coming out? and how much water has been removed from those 40 gallons (how many concentrated gallons do I end up with?)

I am trying to figure out how one makes the decision between bigger and bigger evaporators versus adding a RO machine and keeping a small one?

Also, if you run sap thru an RO machine and then run it thru again, does it continue to work?

[saphead]

Reverse osmosis,Jones rule of 86 and a little math= $ well spent on an RO. Let's use 43:1 which is 2% sap,86/2=43.Run that 43 gallons through an RO and bring it up just 1% and you have 28.7:1. 28.7 gal. of 3% concentrate and 16 gal. of permiate. It all depends on what you're comfortable with for % concentrate going into your evaporator, your g/hr boil off rate,gal. of sap to process,the gph of the RO,and TIME available to boil.Not to mention the fuel savings! Where I work if we can run it through the RO ahead of time we'll bring it up to 10%, that's 34.4 gals. of that 2% going bye-bye and 8.6 gals. going into the holding tank! But boiling with a 6x16 ,once we run out of whats been processed ahead of time, we adjust the output of the RO to the boil off rate of the evaporator.It's an old RO and it can't keep up with the rig @ 10%. Hope this helps a little.( now you can see why people who buy sap pay close attention to the %)

[powerdub]

This may get a little long but here goes. Please allow me to address your question from last and work them backward, sort of. I bought a 240 gallon an hour machine last year. I was boiling on a 30"X8' evap. I can process 85 GPH the way it is set up. I have 1100 taps out +/-. On a run of 1000 gallons it takes, including start up and cool down 13 hours to process that sap. Working a full time job and boiling for 13+ hours did not give me a lot of time for sleep. I went to a sugaring show to buy a larger evap. 3.5'X10'. with preheater hood and insulated arch front. $12,000.00. Leaders price with revolution pans. I wouldn't even double my out put with that kind of investment. Enter the used RO machine and I might add I was quite apprehensive of used at first. He wanted $2,500.00 for it. Now I start the RO machine when I get home from work and let it run for an hour while I have dinner with the family or walk my lines or pick my nose. You get my point. I start boiling about 5:30 and am usually done and home in bed by 11:00 at the latest. I bring the sap from 2% to 8% or whatever it is. I still process 85 GPH but now I am pouring off about 8 gallons of syrup and hour as opposed to maybe 2 gallons an hour before. My reccomendation on a size RO machine is figure the rate per hour of your evaporator and compare it to an RO machine that match it on the concentrate. The flow rate for my concentrate is 1.5 GPM for 8%. That is 90 gallons of concentrate per hour. The water coming out of it is around 4 gallons per minute. The wost thing is running out of concentrate before you finish processing the sap. Been there done that. Yes, you can run your machine longer before you start to boil but point is to process the sap in the least ammount of time. So, you ask why don't I just oversize the machine to say a 600 GPH. I guess you can but then you are increasing your cost for no reason. (my opinion) Now, to address some of your operational questions. At 40:1 your sugar is running about 2%+. With my machine and every one is a little different, I run that forty gallons of sap through at 1.5 GPM of concentrate it comes out at 8%. You have just gotten rid of about 30 gallons of water and kept 10 gallons of concentrate. That 10 gallons will now make 1 gallon of syrup. You can adjust your machine by increasing or decreasing the concentrate flow rate to whatever % sugar content you want, to a point. I know some guys that concentrate to 14% but they are buying membranes every 2 years. They should last 10 to 12 years if you take care of them. You can pass the concentrate through your machine again and get a high % out but again it is hard on the membranes. I hope I have answered all your questions and feel free to e-mail me if you want more info. I am certainly no expert on all machines but I know what mine does and let me tell you I love it. Getting sleep at night is wonderful and it brought joy back into sugaring for me. One more not of interest I may add is I use wood and the time it has saved me in the summer for putting up is nothing short of awesome. I have cut my wood consumption down by better than 2/3. If you use fuel, giving the price these days that is a great cost savings. You need to figure out your power cost but I think it is still cheaper to use the electricity.

[farmerEd]

Wow, those numbers are all pretty impressive...so in your example, taking my 2% concentrate to 10%, will reduce my 43 gallons of syrup down to 8.6 gallons, so even on my little Half-pint (which I plan on upgrading) if I started with a 430 gallons of sap, ran it thru the osmosis machine to 10%, I would end up with 86 gallons of concentrate, and that would give me about 10 gallons of syrup in about 20 hours of boiling (now in 20 hours of boiling I get about 3!)

Wow, guess I need to re-think how big an evaporator I need to upgrade to....

Is there a downside to using an RO? Is it just a cost factor?

Once you RO the sap, can you dump it into tanks and save it just like sap? i.e. run the RO everyday and just boil on the weekends to cut down on the storage tank requirements?

[Brian]

The concentrate must be boiled right off because of bacteria growth. The growth of bacteria is very rapid .

[Parker]

Hey Brian-
What if you keep it in a refridgerated bulk tank? How cold would you have to keep it? and how lond would it last at say 36 DEG.?

Parker

[Brian]

Parker, that is a good question I will ask Glen when I see him.

[powerdub]

I would talk to an RO manufacturer. I need at least 500 gallons of permeate at the end of the day to rinse the membranes. If you get a smaller machine I don't know if you need as much water. One down side is they do consume power. Mine is a small machine and take 60 amps. There are some other operational expenses like 5 micron filters, membrane soap and storage solution. I would recommend a sap refractometer to make sure you are not passing sugar. I don't know how big your set up is or how many taps you have but it sounds like you are not that big yet if you are on a half pint now. You may be better off getting a bigger rig first and then taking it from there. I bet you could get a new 30"X8' for under $8,000.00 complete. A new RO, even a small one will run you at least $4,000.00. I am price guessing here.

[Salmoneye]

You can take RO concentrate and pass it through an inline UV 'sterilizer' and then into a refrigerated bulk tank and it will keep fine if the tank was clean to begin with...

The one downside of RO IMHO...

I don't think that the syrup has the right consistancy or taste...I firmly believe that syrup needs the long boil to acquire the 'correct' carmelized colours, flavours and invert sugars for the right taste and feel on the palate...

All IMHO of course...DO what works for you...

[mapleman3]

Salmoneye.. I happen to agree with you on that point!! I think the longer heat helps the flavor.. but there are alot of RO's out there and most will disagree with us. sorry guys, not bashing your syrup at all. just think it's a little different tasting than non RO :wink:

[Salmoneye]

I was certainly not trying to bash anyone either...

I fully understand the need for RO on large operations...

I just want to personally keep myself to a size that I can sustain with wood and no need for RO...

Just my preference...

[Brian]

Glen said don't store concertrate more than 4 hours nomatter what

[wdchuck]

As to the taste of syrup of syrup made with an RO, I used to be convinced that it had a different flavor, based on the samples I've had (plenty!). After taking the plunge and buying the machine, I no longer think thats the case. I dont know what causes that change to a flatter, mellower flavor from that nice fresh bite of fancy right out of the evaporator, but from my experience, it aint the RO! We've even had our friend Frank,our official taste tester and a guy who knows what good syrup tastes like, and he says theirs no difference between the results from this years RO'd syrup and our old way of doing things. Personnally, I think the trick is to have the machine sized properly for your operation so that sap isnt sitting around for too long, either waiting to be RO'd because you dont have enough to boil, or letting the concentrate sit for too long. It's not the machine, but something else in the process.Any thoughts?

[powerdub]

I'm with you wd. I was the biggest skeptic until I compared my non RO syrup to the RO syrup I made the following year and I could not tell the two apart. You may be able to taste the difference between mine and your but I doubt you could tell which one was RO.