Steam Boiler Help a Little Operating Info

[Absinthe Pete]

I've never used a steam generator (steam boiler) before and have a few questions for those of you out there who do use one. Can they be regulated? What I mean is my boiler is rated at 150,000 BTUs and I'll be using the full amount to heat up the wash in the still, but after that do I turn down the steam pressure or volume to match what I want as output on the distillate? or do I just keep it full blast?

Thanks. I need this info as I'm building the still from scratch, lots of still building experience but never with steam so I need to know the heat input is so I can design the condenser to keep up.

Oh it'll be a maximum of 150 gallons of 40% wash at a time in a pot still.

[robertbirnecker]

Dear Pete,

First of all, you need to know the maximum operating pressure of the still you are building, I assume low pressure steam meaning 15psi or lower to put all the appropriate safety devices on.

150GAL usually require a slightly bigger boiler than the one you have available. It basically means your heat up will take a bit longer.

As for the steam regulation, you would regulate the flow of steam relatively basic with a globe valve or a ball valve, also reducing the pressure inside the still.

There are more elaborate management systems with digital measurements and automatic adjustment of steam or pressure reducers that go to certain setpoints but they are also more expensive and require some more knowledge.

Hope that helps.

Robert

Kothe Distilling Technologies Inc.

5121 N. Ravenswood Ave

Chicago, IL 60640

http://www.kothe-distilling.com

http://www.kotheconsulting.com

info@kothe-distilling.com

(312) 878 7766

[coop]

I've never used a steam generator (steam boiler) before and have a few questions for those of you out there who do use one. Can they be regulated? What I mean is my boiler is rated at 150,000 BTUs and I'll be using the full amount to heat up the wash in the still, but after that do I turn down the steam pressure or volume to match what I want as output on the distillate? or do I just keep it full blast?

Thanks. I need this info as I'm building the still from scratch, lots of still building experience but never with steam so I need to know the heat input is so I can design the condenser to keep up.

Oh it'll be a maximum of 150 gallons of 40% wash at a time in a pot still.

Pet, I use steam for my Holstein still. My boiler is rated 195,00 btu input. Not sure what to output is but it is pre set at 5 lbs of pressure output however when I run my mash kettle and still at the same time I needed a little more than the 5 lbs output. After contacting the manufacturer he advised me on how to raise the output steam pressure to 7 lbs with a simple adjustment to one of the controls. That is as high as I can safely take it. Hope this helps, Coop

[Beauport Bob]

Again I agree with Coop.

But, steam is steam.. You control the flow to control the temperature of your pot, and the bioler will shut on and off as required. I recommend speaking with a plumber. Have you thought about condesate return? New water for a bioler is life shortening. I have redundant alarms on the condensor tower of the still. If it gets too hot the boiler will shut off and a whistle will blow. If anyone remembers visiting us here in the early days you would have heard quite a slam when the water feed (Backflow preventer)closed. We solved that with a spring loaded pin rather than a flapper. Wait, are several of my comments pertinent to another ongoing thread on Steam vs Direct heat source?

[Beauport Bob]

sorry, "Boiler" not Bioler.

[Absinthe Pete]

Thanks for all the replies, Bob, what did you mean by "New water for a bioler is life shortening."

[Guest tom]

For a 150 gallon, I would not go less than a 750,000 btu. You cannot make money waiting on the still to get heated up.

[Beauport Bob]

Good morning AP,

Caveat: check everything out with a professional:

I have see some operations where there is not a full loop for the steam condensate to go back to the boiler. As the steam transfers heat to the pot or other point of use, it will cool, more if the BTU number is weak or pressure is low, that cooler steam partially is condensed to water. That water has to be bled off so there will not be a blockage (heavier material) in the way as the steam travels back to the boiler. Your home heating boilers will have an expansion tank or a bladder for this purpose. Some people bleed off the condensate, not collect it and send it back to the still, always requiring new water: 1)to be brought up to steam: new water +/- 50 degrees f, return condensate around 190+ f 2)the thermo shock of a cooler water being introduced to the hotter plates: bang bang bang, and 3) continued introduction of natural or added corrosives to the plates in your boiler: the muddy stuff when you drain to comes from somewhere. We have a condesate return tank (20 gallon?), aquired from the still manufacturer,B-H, that collects and feeds the boiler as required. If there is not enough in the tank to feed the boiler the tank has a float valve from the municipal supply. If there is too much, overflow of the tank will help clean your floor. that has only happened once to us in 4 years.

One more gem, most commercial built pots that are steam fed should have a drain on the bottom. Ours is on the condensate return line. The lowest point. Condensate return is not steam return.IF COOLBefore use, drain that section before or as starting the boiler. If not, that will act as a blockage until steam pressure pushes it through. Effeciency and pressure are your concerns.

The effects of which I speak will not show up immediately, but you'll be upset when your 20 year boiler lasts only 15 years. Surely this all is relativly more important as you go up in still and boiler size.

Again, cherk with a professional.

[Beauport Bob]

I forgot #4: There is a cost return for us besides the effeciency of the boiler. Our water here in metro and north of Boston is among the most expensive in the country. Less I use, Less I pay.

Bob

[coop]

I forgot #4: There is a cost return for us besides the effeciency of the boiler. Our water here in metro and north of Boston is among the most expensive in the country. Less I use, Less I pay.

Bob

The life time of a boiler or just a hot water heater is determined by the manufacture. His trick is he is using distilled filtered water. If you have any minerals, mud or other contaminants from using a domestic water system or worse in well water you really need to use that drain that if furnished on everything, even daily may not be often enough. We are lucky here after three years of running nothing is building up within our steam system at all. When I blow the valve on the boiler no rust, dirt or scaly build up blows out at all. Even the state boiler inspector was amazed. I have a dual cartridge system on the inlet of the water and blow once a month anyway. You must keep your boiler jackets clean. Clean jackets=clean steam= clean stills. Coop

[MarkR]

One thing that I keep seeing on distillation systems powered by steam is an almost universal lack of insulation on any steam or condensate return pipe. Unless you are trying to heat your work space with the boiler, you are just wasting energy and money without insulation on those lines. If in fact you are only wanting to heat the still, or perhaps a mash cooker, with the steam, insulating those hot pipes (touch any lately? Not real safe having 110C pipes where your hands go) will allow controlling the steam demand at the still, where you want the control to be. A couple of rules work here (1) Supply has to a fair bit more than demand, or you will have an overworked and poorly working boiler; (2) Avoid if at all possible feeding cold municipal supply water into an operating boiler, as it will drop the supply pressure immediately; (3) Keep the supply lines as short as possible and insulated to avoid losing energy to ambient cooling and slow reaction of the supply to changing demand. (4) Keep in mind that pressure equals temperature in low pressure systems, and if you are running a boiler that has the relief valve set at .4bar and is putting out saturated steam at that pressure, the temp at the start of the pipe is about 110C, and there is 100ft. of 1 in uninsulated black pipe between the boiler and the still the temp is probably closer to 102C. Not much extra energy there to heat a couple of hundred pounds of stainless steel and copper and a bunch of mash. Open the steam valve suddenly, and the supply can't keep up with demand and no wonder the system drops in temp until the boiler can catch up. At the other end of the system, the condensate return should also be insulated to avoid cooling the boiler expansion/header tank too much.

[Max Action]

For a 150 gallon, I would not go less than a 750,000 btu. You cannot make money waiting on the still to get heated up.

I'm also investigating boilers but keep hearing inconsistent advice on sizing. The above recommendation seems a bit high compared to what I've heard elsewhere, for example Vendome recommends 250K BTU of steam for a 125 gallon system, but I'd be curious to hear what size stills and boilers others are using, and how long their distillation runs are taking.

[coop]

I'm also investigating boilers but keep hearing inconsistent advice on sizing. The above recommendation seems a bit high compared to what I've heard elsewhere, for example Vendome recommends 250K BTU of steam for a 125 gallon system, but I'd be curious to hear what size stills and boilers others are using, and how long their distillation runs are taking.

The one we use is rated at 245,000 btu but that is at sea level. We are at 6100 ft and our still is a 300 ltr. It takes about 2hr 45min for the first run of the day then each run gets shorter after the still has been heated up. But remember you can never have too much steam so larger is better. Coop

[Brian]

Here is a good source for all things steam: http://www.hoffmanspecialty.com/HS-General-Catalog.asp#9

You can poke around in here and get a sense of what does what to whom.

Be careful if you are considering direct injection of steam since you will need to consider any taint added to your process.

You could gang up two or three smallish low pressure boilers and have each boiler at a different "pressuretrol" setting which would kick on more/less boilers as your heating need changes from say cooking and distilling to cooking only.

blow down is a daily task with steam to keep sediments circulating to a minimum.

If you have a "boiler feed pump" (search term for Grainger or the like) condensed steam will be re-injected into your low pressure system. If you put up a simple water treatment system form say http://www.ohiopurewater.com/shop/customer/home.php you could de-mineralize all your water for boilers, mash, RO system with a relatively cheap A/B system....one refreshing and one in service.

Look on E-bay for steam boilers if your are on the east coast...."slant fin" has a decent but "residential" boiler reseller there.....buy a couple 250K boilers (or whatever) and gang them....I got a nice boiler out of a church in Cincinnati....brought it home in pieces....got a new gasket kit and viola....trickiest thing about steam is that water flows down hill...all pipes tilt back to mama boiler....belt and suspenders, meaning pipe joint paste with teflon tape over....get the manual from the MFG for new or used systems and follow their guides for the off take (steam source) manifolds.....you will save lots o'cash and know your system inside and out...

Best,

B