Steam powered

[325abn]

I have acess to a 20KW steam generator for free. Bascoms evaporator is powered by steam so I am wondering if I could use this small steam generator to power my 2x4.

The one at bascoms looks like they just have steam circulation pipes running the lenght of the pan.

I sopose if this was a good idea it would have been done already. Has anybody seen a steam powered evaporator other than Bascoms?

Any input on this idea?

[DS Maple]

There is a section in the North American Maple Producers Manual about the use of high pressure steam in maple systems. The section is somewhat informative on its own, but it also makes reference to another book; The Use of High Pressure Steam in the Production of Maple Products by D. Chapeskie. This sounds like it would probably be the best source for this type of information.

[mapleman3]

if you had the time to play with it a bit it may be interesting... make your electricity too !!

[802maple]

We have atleast 4 producers here in Vermont that use steam.

[Maple Restoration]

Hi DS there is a maple producer not far from me he was one of the first to run with high pressure steam here in Ontario you can check out his web site www.matthewsmaple.com , He has had some of the larger producer from Quebec to check it out. For they need to be licensed over their. His boiler is oil fired and he run it at 100 psi of steam, it really seams to be very cost effective and he just added a steam-a-way to his rig this year, it was the first time that leader had ever seen a rig like this. I hope this helps you on some info.

[Toblerone]

I don't understand. What is the point of boiling water to make steam to boil water? Why not just take the oil burner from your boiler and put it on your evaporator? What am I missing?

Dave

[NH Maplemaker]

The first BIG thing that comes to mind is ,you don't have to worry about burning your pans!!! It would also be much cleaner!!

[325abn]

I don't understand. What is the point of boiling water to make steam to boil water? Why not just take the oil burner from your boiler and put it on your evaporator? What am I missing?

Dave

The steam generator is electric powered.

[Toblerone]

Just for fun, I did some calculations for using electricity vs wood. I assume that the efficiencies of burning wood directly under the pans to heating steam that would then heat the pans to be similar. Maybe I am wrong about that, so adjust the numbers accordingly if you think otherwise.

For electricity:
20kWh*$0.08/kWh = $1.60/hr (my guesstimate on electricity cost)
20kWh*3412Btu/kWh = 68420 Btu = 0.06842 MBtu
$1.60/0.06842MBtu = $23.38/MBtu

For wood:
15MBtu/cord for mixed hardwood (my guesstimate from the wood charts)
1 cord = $150 (guesstimate)
$150/15MBtu = $10/MBtu

So electricity is more than twice as expensive as wood (at $150 per cord) in terms of heat content. Efficiencies could make them more or less the same but I don't have any data on that.

Dave

[325abn]

I havent got that far at all. I just got word of this steam generator and thought of Bascoms rig and got to thinking of ways to use this steam generator. Maybe steam is only ecoonmical at the size Bascoms is.

I think it would be some sort of high pressure closed system with the steam circulating though the oan via circulating pipes then back to the steam generator.

[Maple Restoration]

The rig that is down the road from me is a closed system that runs and oil fired boiler to create 100 psi of steam to run via long “u” shape coils that sit inside the pans ½” off the bottom to boil the sap. You can go from cold sap to full boil in about 30 seconds the nice thing is you can never burn you pans or the syrup with this system, when you run out of sap it acts as a big heater till you shut the boiler down. He averages about ½ gallon of oil use for every gallon of syrup made, his back pan is around 4’ by 12’ with two coils and his front pan is 4’ by 5’ with 4 coils one for each gate. He just added a steam-a-way this year and it should greatly reduce his oil cost. And this is all on 12% concentrate to start from.

I hope this explains things a bit.

[Toblerone]

Ok I get it. It must be that the boiler is really efficient and the sap is boiled in what amounts to a giant heat-exchanger so all of the heat generated by the boiler is transferred to the sap.

[TomE]

Mike,

The rig you describe sounds pretty neat! Can you estimate the diameter of tubing he is using for the U-coils?

On the subject of never burning your pan or syrup--do you know if they ever see scorching on the coils (especially as they become un-submerged)? 100 psi steam has a temperature of ~328 F.

What does the boil look like--does it boil throughout the pan, or mostly just around the coils?

Thanks,
Tom

[Gary R]

I work on electric powered steam generators from 20kw to 120kw all the time. The 20kw we use have a heat loss of 850btu/hr. It could be insulated even better. I don't know the efficeincy of a wood fired but I bet it's less than 40%. Seems like most guys have stack temps of 700F just to keep the back of the pan boiling. Huge amounts of waste, but it's needed because the heats moving. All the generators I work on are 3phase. You could operate elements on 240 single phase. You would need to know what your doing. I've never seen a steam evaporator, but we heat water to 200F all the time. A thermostatic trap is placed in the outlet of the evaporator. When the steam cools it condenses and is released through the trap, maintaining the heat in the pan. At 80psi steam is around 300F. A few other things would be needed.

Sounds like a good idea. I think you would want to do a good cost analysis before you jumped into that one though.

[325abn]

Gary
Maybe I could pick your brain when / if I get going on this. The steam generator I am getting is a old Amsco unit used in a hospital to generate steam for the sterlizers.

I will get more data on the generator.

[Gary R]

That's who I work for. What would you like to know;)

[TomE]

It is a cool idea, but may not be too practical for home use (unless you have a dedicated electrical service to your sugar house)--20kW of power would need ~83 Amps @ 240V. Most home users have either 100 or 200A, 240V services to their homes, and the average outlet (such as a dryer) is only 30A.

You may be able to de-rate the unit to run at less than 20kW to get the amperage down, but you probably won't be satisfied with the evap rate. According to my calculations (which could be flawed), I estimate a theoretical max evap rate of ~8.4 gal/hr at 20kW--these calcs assume 100% efficiency. The real story is there are a lot of other losses in the system that may knock off 10% or more (even though the generator appears to be 98% or 99% efficient).

If you are serious with this project, you need to figure out what Voltage/service the unit needs (480V, 208V, 240V??? and whether it is single phase or three phase--not a common service for a homeowner), and the cost of making the generator compatible with your electrical service. You then need to find out if the output power of the generator will be de-rated as a result of your electrical service, and finally make the decision whether or not you will be happy with the boil rate.

Hope I didn't confuse things too much...

Tom

[325abn]

That's who I work for. What would you like to know;)

Are you a sterlizer guy? I am a Biomed in a small hospital in VT.

[325abn]

I am not to serious at this point. I am just thinking of things to do with this generator.

I will be focusing more on getting my hobby RO upand goingfor next year.

[Maple Restoration]

Mike,

The rig you describe sounds pretty neat! Can you estimate the diameter of tubing he is using for the U-coils?

On the subject of never burning your pan or syrup--do you know if they ever see scorching on the coils (especially as they become un-submerged)? 100 psi steam has a temperature of ~328 F.

What does the boil look like--does it boil throughout the pan, or mostly just around the coils?

Thanks,
Tom

Tom the coils are ¾” tubs and the boil is the full of each channel it is really really neat.

[Gary R]

Yes I am. 14 years in the field servicing. Amsco was bought by Steris about 12 years ago. As others have mentioned, it takes alot of electricity to run generators. If you lived in town near the east coast and had cheap electricity it might work out. Around here if you look hard enough you can get wood for $100 a cord. Mines all free and unlimited:) . We use and discard a lot of handy items for the tinkering mapler. My pan, 304, 18ga stainless. Side panel off cabinet enclosed sterilzer. When we remove these from service this type of stuff gets thrown away.

[325abn]

Small world isnt it?

I worked for Kinetic Biomedical Services which was born form Amsco back in 1990 or so. A few years ago Kinetic was bought by Crothall service group and is now Crothall Clinical Equipment Services.

[Gary R]

Yep! small world. I have worked with 8 different Kinetic Biomeds over the years. There are only 3 left in NW PA. John Truran, Doug Miller and Chuck Shettler. Crothall has lost a lot in this area.

A few years ago my father and I were moose hunting in beautiful Maine. We looked at a map and said lets try here. Anyways when I got back I was telling my story to a Biology Professor at a local college. We started talking towns, roads ..... houses. He was born and raised on the ground we had been on. The land is vacant and own by big timber now. He still goes up at least once a year to visit family.

Let me know if you have questions about our equipment.

[Maple Hill Sugarhouse]

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[325abn]

325abn- I'd take the steam generator and sell it to someone that has a system (boiler) that will run it-Certainly it wouldn't even be cost effective for you to even thing or try and get it running for yourself/better off to stick with the small evaporator or what ever you have for a boiling sap rig now.

Having ran boiler rooms for about 14 years now and ran the 400Kw steam turbine that used to be working at the mill many moons ago=you'll have more headache's trying to set up a system with the menagerie of pumps,pipes,traps, Da tank and chemical feeds and chemical test that tell you what to add for additives if you want the thing to last/need to be check daily and all the safety's and permits for operation it would cost you 1/2 a brinks truck to set-up/never mind telling you how the whole system is suspose to work=thats another book in itself. Usually there are not many problems/but if a serious one arises you need to react fast in the proper way or boomski.

I certainly don't have enough time in a day to tell you what you need to know/you could always snoop around and see what others systems look like. but you'll probably find out it's not $ feesable for the adventure.

You are probley right. Chances are the thing will sit in my barn unused till I get rid of it. :)

[Gary R]

Those units are only the size of a 2ft. cube. The unit it came from had all the check valves and traps you would need. Pump and all the controls and safety devices are on it. I have some customers that have done nothing but drain them (cool) once awhile. They have been running every day for years with no maintenance. A good point the Govenor mentioned is that these are pressure vessels that are supposed to be permitted and inspected by the state. If you had a major catastrophy and it wasn't, you would be in DEEP CRAP.

Best stick with wood:)

Sorry one last thing on this. As the OEM representative for that generator, if you haven't been trained by us, Don't touch it:)

[Maple Hill Sugarhouse]

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