Hope this catches some eyes. I dont know if anyone has tried this but its a thought. Steam jacketed storage. A 500 gallon lp tank for the jacket and a 120 for the storage. Pipe inside of pipe.Im not trying to reinvent the wheel but im wondering how efficient that would be. Im new here and I have some ideas but not sure how much sense they make.I posted earlier asking if the tank being horiz-vs.-vert had any bearing on effeciency. I know this would entail lots of fab but im thinking it just might be worth a shot.Any comments or ideas would be HUGE-Thanks Eric
An idea-the difference between being insane and genius is success
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There is an ENORMOUS amount of heat energy involved in making the transition from water to steam and back. That makes steam a very efficient medium for transporting heat. Interesting that there are no real steam wood boiler out there - at least none that I know of.
Indeed they do. I have one-e 180. Just got finished pipen a tarm 40 for a friend. In conjuction with a fossil fuel boiler.Tig welded system-zero screwed pipe. All stab ins are weldolets-ZERO leaks on start up.Not tooting my horn but ive been a pipe welder for 22 years-Hell if you do something long enough-umm-well u better get good at it-LOL! Anyhow this sight is great and I enjoy it lots. No carrying on and what not. Using the hydronic system(hotwater) you feed from the top and return through the bottom.(storage wise)You could feed steam the same way-condensate on the bottom-only makes sense.I know lots about jacketed pipe and I know what makes them fail.If anyone has questions on here about welding or any piping related matters umm Ill give it my best.I know a little and I am into bartering.Like I said I purchased this WG a short time ago.Its in my barn. My friend who I installed the boiler for is a carpenter. My barn is a hundred years old.Well its currently insulated and being sheet rocked. Like I said-to barter is best its like free wood. Anyhow im just curious as too why no one has done this. Eric G<<<<<<<<<<<<<seeks enlightenment.
My guess (and it's just a guess) is that it probably has a great deal to do with the extra safety concerns and gov't regulations that are involved with doing steam rather than hot water - It is bad enough dealing with hot water, at least here in MA where the ASME operates the boiler safety rules people and believes in screwing over the consumer in order to peddle their certifications... Steam is yet another layer of headaches on top of that.... More permitting, more inspections, more fees....
Gooserider
Gooserider
I thought that the idea of storage is mass, the more mass the more btu's. Wouldn't you be reducing your btu storage by having that much area taken up by steam? or is the energy density of steam higher than water per volume? if the density is higher then why would you bother with the 120 inside the 500?
curious
curious
Gooserider said:
Pretty much hits the nail on the head Goose. ASME has its place but it's not in residential equipment. The new CSD-1 standard for testing is nothing but an meaningless financial burden for 90% of the boiler owners I have to do it for. I think that ASME should stick to stuff operating at over 30 PSI and let everything below that alone. Heck, here in Michigan a homeowner can't even pull a permit to install a boiler in his/her own residence, ASME or not. That runs crossways to my libertarian streak pretty hard. Seems like this country had a small uprising in the late 1700's over similar matters.............Maybe it's time for another one.
I think the main reason for the lack of steam/wood combos is that the issue of sizing becomes even more critical in a steam environment and it adds another dimension to the whole process . For instance, in the scenario suggested above, the boiler output should be sized closely to the ability of the storage to soak up the heat (condense the steam) rather than being sized to the actual heat load of the structure. True, the same could be said of a hot water based system but the added step of the vapor cycle involved in evaporating and then condensing brings a bit more complexity to the table from my way of thinking. But hey.....whatever turns a guys knobs..... Not saying it couldn't be done.
heaterman said:
You'd get no argument from me on that one... (FWIW, I am a long time LP member, former LP-Mass. State Committee member, delegate to most of the past National conventions, and so on - I was even a potential "Presidential Elector" last election, assuming the LP had carried the state (not likely...)) Far as I'm concerned, we would have been far better off if the Whiskey Rebellion had succeeded, not to mention some of the other efforts over the years to take back control over our government...
IMHO there is some evidence that our "leaders" are also worried about that - note the frequent attempts to do away with the 2nd Amendment, and remember the first uprising occurred when an effort was made to take away people's "assault rifles"...
Getting back to the main subject -
I don't think the idea is to store "steam" as such - rather to use the boiler to make steam, and then use the steam to heat the storage - in theory one can move more BTU's faster this way... Potentially if one raises the system pressure, one can also hit storage temps well over 212°F although this can be very risky as a leak can lead to the stored water all turning to steam at once (i.e. BOOM
) In general, steam is a very good way to transport heat, but it has a limited value as a storage medium because it can condense. The other issue is that steam CAN be more fussy about being handled properly - if it isn't, the results can potentially be much more dangerous, essentially because of it's greater energy capacity... If you mess up with a hydronic system, the failure modes can be messy, as in floods, or you get no heat, but the risks of catastrophic property damage are relatively low... Steam can potentially cause building leveling explosions, so it is more like dealing with a propane / natural gas system...
Gooserider
I think it usually turns to mass but it's really BTU's. If you can find a material that does a state change in your operating temperature range then you have a way to "pack in " more energy. 212°F H2O Liquid to Vapor (change of state = Latent Heat of Vaporization) requires 1000 BTU of energy (960 for 1 pound water ) so the "magic is in the state change. The temperature is still 212 but you have added 1000 Btu's to your storage.
Some other popular thermal storage that I'm sure must have been discussed before: Glaubers Salts, Paraffin wax are both in the discussion because they do state changes in the "right" temperature ranges --All of which come with their own hassle water is some cool stuff.
Anyone out there using a PCM salt ? I was thinking about filling up some bottles with it and dumping it in my water tank as a way to extend the storage time in the same volume like the solar folks do. They fill PVC pipes with the stuff and cap them then use water to transport the heat. I did find some that work at 118 , 150 or 160 would be better.
Gooserider I agree. Steam can be a nasty bit of business. My thoughts on the temp in the storage would be below the flashpoint though. Im familiar with it and I know it can be deadly. 1 gallon of water can make 1500 sq ft of steam in a split second(flashing) when over 212 dagrees and exposed too the atmosphere. Umm I could be wrong but I think A.S.M.E. was started when they started racing riverboats. It was developed to protect lives. They used too evrdrive those things till the point of explosion and ppl died. The welds in the piping sytems were not up too snuff (BOOM!). In a residential system the pressures are relatively low and as long as your not heating storage beyond 190 I'd think youd be relatively safe. The thought of having 500 gallons above 212 is pretty creepy.If the vessel did fail it would be roughly 750000.00 sq ft of steam instantly. Youd here the BA but not the ANG! and your roof would probably land on mars somewhere. Maybe a lone pipe sticking out of the ground where your house once stood. Im just curious as too how fast or how much more effecient the volume could be heated VS's water. The jacketed vessel is probably not a good idea as far as volume and space goes. If you were to build a jacketd coil(pipe inside of pipe) with 180 dagree tube turns you could fit that into a relatively small space. Have your storage water circulating into the bottom and out the top and back too the top of the storage-with the steam in a reverse flow obviously. Maybe have a throtteling valve too get the best possible exchange. Keep the water ,water and the steam ,steam.
I recall that there was a high performance 18th century boat (I think in the Adirondacks) that burned solid fuel and had an engine that ran on the same concept as a steam engine, except it used a different volatile compound, in a closed condensing system
-- pretty sure it was actually benzene (gotta hope there were no leaks of hot liquid or vapor)- which stands out in my mind because the whole idea of highly heated pressurized volatile hydrocarbons anywhere near a fire made me think that the designers and operators must've had a death wish.
By the way, if you like steam- or just for fun, anyway, rent the Anime film "Steamboy"
-- pretty sure it was actually benzene (gotta hope there were no leaks of hot liquid or vapor)- which stands out in my mind because the whole idea of highly heated pressurized volatile hydrocarbons anywhere near a fire made me think that the designers and operators must've had a death wish.
By the way, if you like steam- or just for fun, anyway, rent the Anime film "Steamboy"
Thanks mwk1000,
I wasn't sure what the purpose steam was. Water is hard to beat as a heat transfer medium. Maybe Eric is on to something though, steam might allow you to get away with an open storage tank with a relatively small 1/2" copper coil heat exchanger, that would lose relatively little on efficiency compared to hot water.
Not something I'll try anytime soon.
I've got some calcium chloride hexahydrate cans that survived the seventies intact, kinda cool but I'm afraid to use them as they start leaking sometimes. I wouldn't want that stuff anywhere near something as valuable as a heating system. I don't even like it in tires, it always rots the rims out.
I wasn't sure what the purpose steam was. Water is hard to beat as a heat transfer medium. Maybe Eric is on to something though, steam might allow you to get away with an open storage tank with a relatively small 1/2" copper coil heat exchanger, that would lose relatively little on efficiency compared to hot water.
Not something I'll try anytime soon.
I've got some calcium chloride hexahydrate cans that survived the seventies intact, kinda cool but I'm afraid to use them as they start leaking sometimes. I wouldn't want that stuff anywhere near something as valuable as a heating system. I don't even like it in tires, it always rots the rims out.
To get back to the original question: using steam in any form is expensive and even more pricey if you try to store it or use it for a storage scheme.
Given the issues with condensation and the amount of energy required to generate steam, I think this one should have a quiet demise.
My 2 cents worth as one who tries to store heat. "Regular" insulation, in any form, is a LOT less expensive and a lot more effective.
Given the issues with condensation and the amount of energy required to generate steam, I think this one should have a quiet demise.
My 2 cents worth as one who tries to store heat. "Regular" insulation, in any form, is a LOT less expensive and a lot more effective.
I guess my original question was considering a jacketed vessel. I have seen them insulated with regular insulation and they do hold heat once the steam has the medium too temp. It would be a task to build but its nothing I havent done on a commercial level. The overall dimensions would be a bit of a problem though. On the other hand the jacketed pipe heat exchanger isnt that far fetched. They use them all the time to heat polymer and keep it in liquid form. Why cant you just use it to heat water instead of polymer? Producing steam with a WG doesnt cost anymore and possibly less than it would to heat 500 or 750 gallons of water than if it was done the conventional way.There is a person on this forumn using a WG as a steam boiler in a pitched pipe system and he seems to like it.Steam is pretty hard to beat as far as heating things quickly. So if you have a regular insulated pressurized storage tank being heated by a steam jacketed exchanger maybe you could put less charge in the boiler too acheive your desired temp.I guess im putting this out there cause its an attempt too get every oz. of effeciency that I possibly can. Oh yah and emissions would also be reduced too. Im not laying this concept too rest cause I know it can be done. Hell I might attempt it and fail horribly but I'd rather try cause I think its very possible
I agree it can be done, but I really don't think it would gain an awful lot... Aside from legacy applications like steam heat where it is done that way because it was the best available approach at the time (i.e. pre-reliable and cheap circs) the applications of steam that I'm aware of are ones where the temperatures / energy content of steam is NEEDED for the application - i.e. you have to heat stuff to a certain temperature, or spin a turbine, etc...
The general rule that I've always seen suggested is to use the lowest energy form available, that will do the job, which would be hot water in this case... With hot water you maximize the heat xfer from the boiler to the water (transfer efficiency goes up as the temperature differential increases) have a medium that transports well (pumps are easy...) and does a pretty good job of transferring it's heat on the other end.
Steam is a little harder to generate, a little harder to transport, (must either be plumbed just right, or have pump to return condensate) and doesn't transfer the heat on the other end that much better over a long term. (Yes, it's faster to heat, but what's the hurry?)
You can't get more energy out of the system than is already there, so I don't see it providing that much of an improvement over the already pretty good efficiency of a hot water system - and even if it did, I am not convinced that it would be enough of a benefit for most of us to justify the added hassles of dealing with it....
Given that you have relevant expertise, it would be interesting to see how you did with it, but I wouldn't have a lot of hope for getting radical performance benefits...
Gooserider
The general rule that I've always seen suggested is to use the lowest energy form available, that will do the job, which would be hot water in this case... With hot water you maximize the heat xfer from the boiler to the water (transfer efficiency goes up as the temperature differential increases) have a medium that transports well (pumps are easy...) and does a pretty good job of transferring it's heat on the other end.
Steam is a little harder to generate, a little harder to transport, (must either be plumbed just right, or have pump to return condensate) and doesn't transfer the heat on the other end that much better over a long term. (Yes, it's faster to heat, but what's the hurry?)
You can't get more energy out of the system than is already there, so I don't see it providing that much of an improvement over the already pretty good efficiency of a hot water system - and even if it did, I am not convinced that it would be enough of a benefit for most of us to justify the added hassles of dealing with it....
Given that you have relevant expertise, it would be interesting to see how you did with it, but I wouldn't have a lot of hope for getting radical performance benefits...
Gooserider
Well thanks for being open minded about the whole thing Gooserider.I know it would involve perhaps a pumptrap receiver or a homegrown flashtank or maybe a combination of the two.Spirex sarco make some pretty neat gadgets too but there pricey as well. I was going for the Nuclear submarine look. Oh well I could always through up some show pipe and pretend-lOl! I guess I was getting wrapped around a wheel so too speak. Any how I gotta get this bundle through the ground before it gets too cold. My masonary chimney has come too a screeching halt because of temperature. I really have too much to do -why am I thinking about this in the first place? Maybe the other tasks are menial I dunno.I think I need a beer.Oh yah after the trench-heavy equipment and alcohol is a no no.
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