Wood-fired Steam Heating

WoodSteam_life

I am from cold Canada and find it surprising that your "Wood fired steam heat" discussion has been discontinued as if there is nothing to discuss, yet firewood is not a fossil fuel, the pollution argument is nonsensical as well.

Wood is a carbon-neutral renewable resource that can be burnt cleanly (mostly steam output) now with 2-stage combustion and much higher efficiency using preheated air in a well-insulated wood-drying sheds 100 feet from the house & 130 feet from the property line, tall stack eliminating breathing hazard and condensing options for even higher efficiency (reaching 90%).

But where are these wood-fired steam boilers as opposed to just wood-fired water heaters for plastic tubes? Or would I have to fabricate one myself?

Jamie Hall

You'd probably have to fabricate one yourself. I have no personal beef with wood heat -- for a number of years it's what I used. At the time I lived in a very rural setting and was much younger. The vast majority of the population would find it difficult, at best, to utilize wood for heat...

WoodSteam_life

I keep hearing that argument and it doesn't make much sense to me. The logs can be brought to the drying shed on a trailer, then thrown into a hole on the side of a wall. Then you grab a few logs per day and put them in the firebox, look at the gauge, check water level and then go harvest some tomatoes from your warm greenhouse.

Steamhead

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

hot_rod

I have installed a handful of gasification wood burners, had an EKO at my own shop.
It does take some work to get them and keep them gasifying. The type and moisture content of the wood, how you load them, wood bridges sometimes and needs a poke.they take some pretty regular attention to keep them burning clean.

When they aren’t gasifying they are not so clean burning. I tried to measure that burn once and it took my combustion analyzer off the chart! I had to send it in for a new sensor and calibration.

Residential steam is not very common in Europe, and that is where most of the gasification wood burners come from. Coal would be a better fuel for steam, and some of the gasification boilers are rated for coal use.

Grallert

I'm sure this conversation is still going on over at Hearth.com.

Jamie Hall

WoodSteam_life said:

I keep hearing that argument and it doesn't make much sense to me. The logs can be brought to the drying shed on a trailer, then thrown into a hole on the side of a wall. Then you grab a few logs per day and put them in the firebox, look at the gauge, check water level and then go harvest some tomatoes from your warm greenhouse.

It is a charming image. you are also hopelessly out of touch with about 90 plus percentage of the population of this country. Sorry. But for those who can, it is lovely.

ChrisJ

Steamhead said:

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

You'd need some kind of mechanical or electric setup that shuts the dampers to put the fire out.
The 1977 Fisher (air tight stove) I have from my grandfather will put the fire out pretty fast if you shut the air damper, so I have to assume such equipment could be made.

I had a pellet stove that could adjust it's blowers via a thermostat, so I'm assuming that could be adapted to throttle pressure etc as well.

leonz

WoodSteam_life said:

I am from cold Canada and find it surprising that your "Wood fired steam heat" discussion has been discontinued as if there is nothing to discuss, yet firewood is not a fossil fuel, the pollution argument is nonsensical as well.

Wood is a carbon-neutral renewable resource that can be burnt cleanly (mostly steam output) now with 2-stage combustion and much higher efficiency using preheated air in a well-insulated wood-drying sheds 100 feet from the house & 130 feet from the property line, tall stack eliminating breathing hazard and condensing options for even higher efficiency (reaching 90%).

But where are these wood-fired steam boilers as opposed to just wood-fired water heaters for plastic tubes? Or would I have to fabricate one myself?

================================================================

The folks from AHS/Alternate Heating Systems in the State of Pennsylvania have atmospheric draft hand fired wood and coal boilers that can be used for residential steam heating.

The issue is one of having a large enough boiler sump that would require less heat energy to raise it 10-15 degrees to reach the boiling point to make useable wet steam that would pass through a double drop header to allow it to expand twice and then travel to the risers at high speed to fill the radiators quickly with dry steam.

A wood pellet burning stoker would work but you would need a large flat grate stoker with forced draft combustion to do it well but if you have a supply of short 12 inch softwood cord wood and the firebox is lined with standard firebrick.

None of the forest eaters made down here are useable to make steam that is why I mentioned the hand fed AHS wood and coal boilers that could make steam.

As a former wood burner that burns the magic black rocks for his only fuel to provide hot water heat and domestic hot water I can offer a great deal of insight to your question.

PEX tubing has become a dominant method of delivering heat to the cold feet down here in the lower 48 because steam gas gone out of favor which one definition of insanity and in many former steam heated homes the steam heat is ripped out for whole house air conditioning and extremely expensive heat pumps that can suffer electrical failures that are very expensive to repair when room air conditioners can be adequate.

No one down here in the lower 48 willingly builds homes with top fed steam or bottom fed steam unless the homeowner or contractor wants steam heat as it is a whole house heating method.

The post WW2 introduction of natural gas from the gulf coast made massive inroads into the heating fuel market filling the pockets of utility stockholders and eliminated the mess of burning firewood and coal for home heating in both old homes and new tract homes in massive housing subdivisions that were close to the new pipelines that allowed utilities to buy "transportation gas" inexpensively to sell to homeowners to make hot water heat and domestic hot water with "stand alone" water heaters power by natural gas.

I grew up with bottom fed steam and I wish I had top fed steam heat here for its simplicity when using a very small coal stoker boiler equipped for steam making.
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Wood fired steam heat needs massive thermal mass to store heat energy and the amount of wood fuel needed to generate useable steam tonnage for the end user comes to the front of this excellent question before it hits a rail car bumper that locks the coupler.

Down here in the lower 48 wood for heating fuel in cordwood lengths and wood pellets has become an expensive cottage industry of sorts unless it is feeding a wood fired steam power plant or a hardwood wood pellet making plant using hardwood wood waste for extrusion of wood pellets for heating fuel for the domestic pellet boiler market and for the export in bulk by dry bulk carrier ship to Europe.

If all we were blessed with was Coniferous forests it may have been different but the Spindletop oil field outside of Beaumont, Texas changed the world in 1901 when the first exploratory well blew out and the world changed then and there forever gradually eliminating cordwood and coal for steam locomotive fuel.

I stopped buying and burning hardwood wood from a long term supplier because he was marking his retail price of "poorly split seasoned in the log" firewood 700-800% when he is paying $35.00 a ton for
sub-standard hardwood logs that are not sawmill quality hardwood logs or they are immature 2 second growth hardwood that has to be cleared by using a tracked or rubber tired boom mounted wood shear or boom mounted chain saw cutting head to access and reclaim harvestable hardwood for sawlogs.

When I first started burning wood and coal in 1982 I was burning 15 full cords of unsplit hemlock right out of a local sawmill that quartered the hemlock logs to sell as dimensional rough cut hemlock waste.
It burned hot and when I split the living daylights out of it to smaller dimensions it made a great deal of heat.

If you live in British Columbia, Alberta, Manitoba, New Brunswick or Nova Scotia a coal stoker boiler used to make steam would benefit from the coal in the western Provinces or Scotia Coal as it is less costly per ton and you would have a much lower amount of ash to dispose of too.
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Jamie Hall

Someone up there posted a comment complaining about the cost of firewood. Full disclosure here: my son-in-law is a forester and logger. "Cut, split and delivered seasoned hardwood" is not quite as simple -- or as cheap to create -- as might be assumed. Logging and forestry isn't jolly lumberjacks heading into the woods, singing songs, anymore. it is hedged around by literal books of regulations. You can't get help to work in the woods (we've tried to hire helpers who aren't positively dangerous and they don't exist at less than close to a grand a day). The equipment isn't cheap, either. Then the price of wood is wildly variable, and anything decent will sell for well over the quoted figure up there for firewood. Firewood is made from stuff you can't sell for timber or veneer, and is usually sold at a loss -- and only because you have to clean up the woodlot. Then you have to saw it to stove length (and a cutoff saw is one of the most dangerous gadgets in the world). Then you have to split it. Then store it for a year or more. Then truck it to the customer. Or you can chip it and sell it to someone to pelletize it, and then they have to market that (and one of the big pelletizers down south just went bust).

By the time you're done, you may -- if the market holds up and nothing breaks -- have broken even on expenses with enough left over to feed the family some beans.

And anything less than 50 acres isn't even worth looking at, never mind moving the equipment onto to do the job.

If you have your own woodlot, and if you have your own chainsaw and safety equipment, and if you have a good splitter, and a truck or forwarder to move it to your cabin in the woods... and are young enough and strong enough, yeah, great stuff. For the average bloke on a suburban lot somewhere, maybe not so much.

WoodSteam_life

Steamhead said:

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

The water cut-off on wood gasifiers blocks air intake and lets make-up water in.

leonz

Jamie, the fellow I mentioned in passing has a has a firewood processor.
He delivers in 2 1/2 or 5 thrown cord lots of 14"-18" hardwood firewood.

One of the reasons I stopped buying from him was that he buried his
10 wheel dump truck up to the axles in my yard and never offered to pay
to repair the damage to my lawn.

Folks fail to realize that it is entirely legal to sell firewood by the ton so that is another
issue. This is where selling firewood in 12 inch lengths makes money and saves
the firewood buyer money at the same time as there is no arguing about face cords
or full cords or the wood species. As long as there is a county or city certified scale ticket
there is no arguing. and the weight is the same whether it is wet or dry wood.

WoodSteam_life

Jamie Hall said:

WoodSteam_life said:

I keep hearing that argument and it doesn't make much sense to me. The logs can be brought to the drying shed on a trailer, then thrown into a hole on the side of a wall. Then you grab a few logs per day and put them in the firebox, look at the gauge, check water level and then go harvest some tomatoes from your warm greenhouse.

It is a charming image. you are also hopelessly out of touch with about 90 plus percentage of the population of this country. Sorry. But for those who can, it is lovely.

I am not claiming to be looking for a universal heating solution, you know.

Many people own acreage and have tons of firewood they’d love to burn for heat at almost no cost to them, but they need serious heat output because electricity isn’t an option for people in need of low-cost BTUs. This is where the rising cost of electricity due to forced electrification is going to apply even to the 90% you think would afford to have their heat pumps on.

Entire logs can be tossed in the box without needing to split them. What’s the big deal about having the load the box three times a day? I’d be happy to load it 5 times a day if need be, that’s the whole point of living a rural lifestyle so that there is always something to do. Rural populations aren't insignificant.

I know farmers up here in Canada who cry over the amount of conventional energy they must purchase in some particularly harsh winters to save their livestock from freezing. They too need representation.

I understand that the demand for wood-fired steam boilers is statistically insignificant, considering the economies of scale needed for warranties and replacement parts, but I bet it’s because people aren’t aware of the latent heat potential of steam for rural living, farming, domestic and small commercial applications.

WoodSteam_life

leonz said:

WoodSteam_life said:

Coal as it is less costly per ton and you would have a much lower amount of ash to dispose of too.

Once again, why so much emphasis on the costs for people who can't obviously afford it? I am well aware of the fact that fuel weight per BTU output makes firewood twice as costly as natural gas. But is this forum limited to universal solutions involving the vast majority of people?

I opened discussion with talking about acreage and wood gasifying steamers for people who strangely enough have no access to such an elegant heating solution precisely because the vast majority tends to dictate common solutions for all.

Here in Canada 11% of the land is privately owned, a lot of which is acreage. It's a large rural community with more than enough of its own free firewood if there was a bit more info on how to make it work. Not everybody wants PEX tubing and countless pumps. Steam puts out 5.3 times more latent heat than near boiling water inside tubes, so long as wood keeps burning cleanly, this is a renewable resource!

leonz

A wood fired horizontal firetube boiler like the ones used on steam powered locomotives with 3 pass fire tubes submerged in water would work for sure the only thing would be designing the firebox in the best way to allow easier loading of pulp wood lengths as long as a smoke bypass diverter is used to prevent smoke and flame from coming out of the loading door.

=================================================================

The Garn wood boiler would be a good example of a submerged fire tube boiler that does make up to 3,200 gallons of hot water in several small loadings with its induced draft burner system using soft wood pulpwood lengths.

The wood has to be very dry(20% moisture or less and one could dry the firewood using a garage heater
creating a kiln to dry the wood with the cooler water returning to the boiler sump.

www.garn.com

hot_rod

ChrisJ said:

Steamhead said:

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

You'd need some kind of mechanical or electric setup that shuts the dampers to put the fire out.
The 1977 Fisher (air tight stove) I have from my grandfather will put the fire out pretty fast if you shut the air damper, so I have to assume such equipment could be made.

I had a pellet stove that could adjust it's blowers via a thermostat, so I'm assuming that could be adapted to throttle pressure etc as well.

Two things about shutting the air off tightly, the fire quickly dies and starts an oxygen starved condition and they smoke like crazy. Creosote forms quickly also. Same when the damper opens again, they belch black smoke like an worn out diesel engine. The biggest problem happens when you close the damper on a full firebox roaring fire, not a pretty condition.

That happens a lot with OWF, owners like to load them up for a day long burn, and leave for work. Weather warms, that close off air and they can smolder all day long. An entire neighborhood is under a cloud of stinky black smoke. Which is why the EPA stepped in and told the industry to clean them up or get rid of them. Many OWF now have some portion of gasification going on, to get them to burn cleaner.

Jamie Hall

I'm not saying that heating with wood -- whether steam or water or air or direct -- isn't a viable solution. For some people. I did it myself for a number of years in Vermont. What I am saying, as I say so often, is that it is one option which can, and should, be considered when evaluating how to accomplish the goal, which is adequate and feasible comfort -- and that there are considerations involved which limit its applicability.

On the other hand (where is my soapbox? Ah... there it is), unless you have a large woodlot and know, understand, and practice sustainable forestry, it is NOT a sustainable jolly green option. Somewhere around 1 cord per acre is about what is feasible for sustained yield in the more northern climates -- including Canada.

ChrisJ

hot_rod said:

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

You'd need some kind of mechanical or electric setup that shuts the dampers to put the fire out. The 1977 Fisher (air tight stove) I have from my grandfather will put the fire out pretty fast if you shut the air damper, so I have to assume such equipment could be made. I had a pellet stove that could adjust it's blowers via a thermostat, so I'm assuming that could be adapted to throttle pressure etc as well.

Two things about shutting the air off tightly, the fire quickly dies and starts an oxygen starved condition and they smoke like crazy. Creosote forms quickly also. Same when the damper opens again, they belch black smoke like an worn out diesel engine. The biggest problem happens when you close the damper on a full firebox roaring fire, not a pretty condition. That happens a lot with OWF, owners like to load them up for a day long burn, and leave for work. Weather warms, that close off air and they can smolder all day long. An entire neighborhood is under a cloud of stinky black smoke. Which is why the EPA stepped in and told the industry to clean them up or get rid of them. Many OWF now have some portion of gasification going on, to get them to burn cleaner.

I was talking specifically about a low water situation.

SlamDunk

After experencing Canadian smoke from forest fires 1000 miles North of me all last summer, I'm surprised there are any trees left.

leonz

You would pipe in the LWCO in series as the first electric control to shut down the boiler.
The BX 2 conductor with ground power wiring would be routed through the first LWCO in an open tapping below the water line and then the BX 2 conductor with ground would be wired into the second LWCO that is in another tapping below the water line and then the next run of BX 2 conductor with ground would be run to the triple aquastat.

According to B+G you could place one of thier LWCO units in the pressure side of the water flow if desired.

ChrisJ

SlamDunk said:

After experencing Canadian smoke from forest fires 1000 miles North of me all last summer, I'm surprised there are any trees left.

I forgot about that.

That stunk.

WoodSteam_life

leonz said:

You would pipe in the LWCO in series as the first electric control to shut down the boiler.
The BX 2 conductor with ground power wiring would be routed through the first LWCO in an open tapping below the water line and then the BX 2 conductor with ground would be wired into the second LWCO that is in another tapping below the water line and then the next run of BX 2 conductor with ground would be run to the triple aquastat.

According to B+G you could place one of thier LWCO units in the pressure side of the water flow if desired.

It'd be great to see a schematic for that, thanks for sharing.

WoodSteam_life

SlamDunk said:

After experencing Canadian smoke from forest fires 1000 miles North of me all last summer, I'm surprised there are any trees left.

It's true that under liberals our firefighting has been underfunded for years but that's about to change due to what happened last summer and future projections of increased heat. Most fires were successfully contained. Most of the timber volume was lost on Crown Land, which is the same as federal land in the United States. Do people not realize the size of this country?

142 million acres of the British Columbian land surface area is forested terrain. That's just one province for you out of 10 provinces and 3 territories.

leonz

It is easier for me to provide you with the owners manual and installation instructions as my hen scratching diagrams are not good.

Enjoy

Jamie Hall

I hate to sound fanatical (well, I sometimes am...) but... any solid fuel fired boiler, steam or hot water, should, in my humble opinion, have two safeties on it in addition to the usual ones. First, a thermal link on the dampers so that if the unit overheats the thermal link melts and the dampers close completely. Second, if is steam, if it is at all possible a gravity water supply sufficient to feed the boiler for the duration of the largest load with no condensate return (as well as a Hartford Loop of course).

Consider. With a gas or oil fired boiler, if the electrical supply fails or is cut off by one of the safeties, the boiler stops -- right now. With solid fuel... it just keeps right on going.

But that's just me.

WoodSteam_life

Here’s one idea,

Let's consider a wood-fired stage-2 boiler (condensing with preheated air). The built-in boiler vessel in that outdoor unit isn't designed to pump out dry heat per se, so how about we add heavily insulated buffer tank (pressure vessel) next to it to behave like a steam boiler up to 2 psi of pressure for the 3" one-pipe counter-flow run put underground but pitched 1" for every 10' to allow condensate to flow back into a separate smaller buffer tank as not to mix with the hottest steaming water in the primary tank.

I can build a basement just for that from scratch accounting for the needed pitch, so yes, the boiler setup would be attached to the greenhouse and the rest of the pipe would go underground for domestic use at a higher elevation.

Can a buffer tank be an effective thermal boiler to coerce enough dry steam out of the system without turning on an electric element inside the buffer tank to get enough steam output?

P.S Please stay on topic, I insist on using steam for heating both the greenhouse and the house where I intend to put steam radiators instead of in floor heat.

Any thoughts?

reggi

WoodSteam_life said:

Here’s one idea, Let's consider a wood-fired stage-2 boiler (condensing with preheated air). The built-in boiler vessel in that outdoor unit isn't designed to pump out dry heat per se, so how about we add heavily insulated buffer tank (pressure vessel) next to it to behave like a steam boiler up to 2 psi of pressure for the 3" one-pipe counter-flow run put underground but pitched 1" for every 10' to allow condensate to flow back into a separate smaller buffer tank as not to mix with the hottest steaming water in the primary tank. I can build a basement just for that from scratch accounting for the needed pitch, so yes, the boiler setup would be attached to the greenhouse and the rest of the pipe would go underground for domestic use at a higher elevation. Can a buffer tank be an effective thermal boiler to coerce enough dry steam out of the system without turning on an electric element inside the buffer tank to get enough steam output? P.S Please stay on topic, I insist on using steam for heating both the greenhouse and the house where I intend to put steam radiators instead of in floor heat. Any thoughts?

It'd be great to see a schematic diagram for that, thanks

leonz

Jamie Hall said:

I hate to sound fanatical (well, I sometimes am...) but... any solid fuel fired boiler, steam or hot water, should, in my humble opinion, have two safeties on it in addition to the usual ones. First, a thermal link on the dampers so that if the unit overheats the thermal link melts and the dampers close completely. Second, if is steam, if it is at all possible a gravity water supply sufficient to feed the boiler for the duration of the largest load with no condensate return (as well as a Hartford Loop of course).

Consider. With a gas or oil fired boiler, if the electrical supply fails or is cut off by one of the safeties, the boiler stops -- right now. With solid fuel... it just keeps right on going.

But that's just me.

=================================================================

No, Jamie you are correct about this for sure. A thermal fusible link like the type used for overhead roll up
corrugated steel doors is a sure and proven fail safe.

You are also correct in saying a water gravity water supply feeding the boiler sump is also warranted. Several folks have used surplus insulated tank cars for a hot water buffer tank for wood burning boilers of their own design that are piped to the tank cars.

A surplus insulated railroad tank car could be used easily with the correct elevation in its setting on a concrete support or wooden cribbing to prevent flooding the steam chest where "I believe" the correct elevation of the water supply in the tank car would be equivalent where the top of the tank car is perhaps level or one foot below the working water level in the steam chest when the boiler is shut down after firing and the water is half way up the sight glass.

The Hartford Loop would continue to work correctly as the water level would be maintained at all times and
continue to absorb heat and if a drop header is used the wet steam would be dried and the condensate would fall back to the boiler or preferably to the tank car as the thermal expansion would be absorbed faster by the open to air blanket-(top space) of the tank car if it is only filled 80% full or 6,400 gallons of make up water.

leonz

WoodSteam_life said:

Steamhead said:

My question would be- how would one apply a low-water cutoff to a wood-fired boiler? I'm pretty sure Codes in most or all 50 states require one...............

The water cut-off on wood gasifiers blocks air intake and lets make-up water in.

------------------------------------------------------------------------------------------

The low water cut off would be installed in a surplus tapping in the water tank if one is available.

These forest eaters have a 110 volt solenoid-controlled damper that controls a sheet metal plate that drops down on the horizontally mounted squirrel cage fans air inlet to stop intake air from entering the firebox when the high limit water temperature is satisfied.

Wood-Steam_Life perhaps the road to follow with this is to use a Garn boiler and additional hot water storage using top fed hot water heat for the new home and green house as you would have the benefit of a huge thermal mass in the open to air hot water tank to heat the home and the green house.

The smallest atmospheric 3 pass Garn boiler is 500 gallons in capacity. Perhaps one of the fully insulated 425 gallon rectangular storage tanks from New Horizons could be a viable option where the New Horizons hot water storage tank could be tied in to the Garn boiler with a small circulator where the hot water would be pumped from the Garn boiler to the 425 gallon fully insulated New Horizons hot water storage tank using it as a nurse tank to add 425 gallons of hot water back to the Garn Boiler with a second circulator for the heating load in the home and a third circulator feeding hot water to the green house.

I have read where hot water is circulated to a livestock watering tank in older homes feeding hot water radiators in Great Britain where the hot water is pumped up into the tank and the water level is controlled by a float valve to start and stop the circulator.

JDHW

Don't steam locos have a lead plug in the boiler? If the water level gets too low the lead plug melts and drops the remaining contents of the boiler onto to the fire putting it out. That is another fail-safe on two levels, either the fire is extinguished, or there is now a hole in the boiler that prevents pressure build up.

John

ChrisJ

JDHW said:

Don't steam locos have a lead plug in the boiler? If the water level gets too low the lead plug melts and drops the remaining contents of the boiler onto to the fire putting it out. That is another fail-safe on two levels, either the fire is extinguished, or there is now a hole in the boiler that prevents pressure build up.

John

I thought they dumped the fire onto the tracks.

Jamie Hall

Steam locomotives are a very different beast -- since they run at more than 100 psig in most cases (sometimes much more!). The threat there isn't so much a runaway fire; the oil fired ones, like any liquid fuel boiler, can be turned off very quickly although they still make some steam from the heat in the firebox brick. Wood and coal fired could be dumped, though in general there's never more than a few minutes of fuel in the firebox at any given time.

The big problem with them is low water. There is a reason for the multiple water gauges on the boiler backhead, and one of the primary jobs of the fireman is to keep an eye on those gauges. The threat is that the water level will drop below the crown sheet, allowing it to overheat and fail -- which is spectacular, but will almost surely destroy the boiler and, sadly, likely the engine crew as well. That's also why there are always at least two feed pumps for larger engines -- and sometimes more.

About the last thing you want is to blow off pressure into the firebox, as it will then blow the fire back onto the deck and the crew, and this can ruin their whole day...

The primary safeties are the safety valves (multiple in all but the smallest engines) and the vigilance of the train crew. The engines can be left overnight with a very small fire (in service engines always are, as firing a stone cold engine is really tricky), just literally simmering, with the pressure relieved -- but any time they are operating there's somebody on deck.

leonz

ChrisJ said:

JDHW said:

Don't steam locos have a lead plug in the boiler? If the water level gets too low the lead plug melts and drops the remaining contents of the boiler onto to the fire putting it out. That is another fail-safe on two levels, either the fire is extinguished, or there is now a hole in the boiler that prevents pressure build up.

John
=================================================================

I thought they dumped the fire onto the tracks.

=================================================================

The excess wood and coal ash that is not blown out of the stack
is dumped from the fire box by manually pulling a lever to dump
the dead ash ash in an ash pit at the water stop and coaling station.

The ash pit at a coaling station has either a plow conveyor or bucket
elevator to empty the pit of ash and dump it in a gondola car to dispose
of the ash later.

A coaling tower usually had a water tank and sanding tower with it on the
fueling track siding in most cases to top off the water in the coal tenders
as well.

The newer steam locomotives had a coal stoker that had a steam powered auger
that had a reduction gearbox to power the auger.

The coal hopper in the tender if it was a big one had a hopper that tilted up to push
the coal forward to continue feeding the fire box when needed.

The hopper lift on the stoker tenders were either powered with a worm that was
rotated using a steam driven motor or a compressed air cylinder or motor if the
locomotive had air brakes-sorry my memory about them is not exact.




They would avoid dumping the fire in the rail gauge as that would start
a forest fire and....... nasty.

WoodSteam_life

I don't know if it's reasonable to expect 212°F inside the thermal storage unit (at extra pressure to overcome 100+ feet of run friction), I might need a smaller tank right after the big one just for that steam, don't know yet, here's the preliminary schematic:

Jamie Hall

I see no benefit to having an independent unfired steam generator tank. If the water temperature in the boiler is high enough to make steam at your system pressure, it will boil... in the boiler. The scheme might work if you had a heat exchanger in your unfired steam generator tank which operated at a much higher pressure and contained circulating very hot (30 psi/230 plus F at least) water from the boiler which would, in turn, boil the water in the steam generator tank. You will also need a pretty good flow of water in that loop At which point, why bother?

WoodSteam_life

Jamie Hall said:

why bother?

Jamie, what do you mean by why bother? And why do I need 30 psi? The higher the pressure the slower the steam travels in the main and the more energy would take me to maintain the system. Steam travels faster at 2 psi than it does at 30 psi.

What I am proposing here is a simple no delivery pump one-pipe counterflow piping system for condensate to return back into recirculation via the same thick main, but since the water would be colder than 180F, I am thinking adding a smaller tank and recirculation pump to take that condensate back into the boiler and premix it if need be to avoid thermal shock. That condensate could be as low as 100F or less.

What do you guys think? How can I guarantee enough steam in the thermal storage unit? (since I obviously can't draw directly from the gasification boiler)

P.S I would load the firebox no more than 3 times a day precisely so that enough thermal storage is built over a 48 hour cycle and system temps maintained uniformly.

ChrisJ

I've never understood comments like "Steam travels faster at 2 psi than it does at 30 psi."

It seems like it's an incomplete statement.

To me, the pressure differential between the condenser and the boiler is what determines the speed of the steam. 30 PSI at the boiler and 0 PSI at the condenser makes for some fast steam.

Jamie Hall

Perhaps I am misreading your diagram, so please correct me if I am wrong. What I am seeing is a "boiler" -- actually a water heater -- on the far left side. The output at the top goes to a T, one leg of which goes down to a mixing valve output (from the diagram). The other leg of which goes through a check valve and into a pressurized bulk tank. The inlet to the "boiler" appears to be intended to be from the pressurized bulk tank, through the mixing valve, and into the "boiler". I see no pumps.

If the output from the "boiler" is hot water, there is nothing to cause circulation. If it is hot enough to flash into steam on entering the bulk tank, it would also be hot enough to boil in the "boiler", unless there is a mechanism to keep the boiler pressure higher than that in the bulk tank.

Now -- is it intended that the output from the "boiler" is, in fact, steam? If so, the check valve will reduce the pressure of the steam and cause a good bit of it to condense, although some will likely get by into the bulk tank. There is nothing I can see to cause steam to condense and move to the mixing valve -- no matter which way it is oriented.

Now this is not to say that you couldn't use the bulk tank to provide additional total water volume in the system. You would take steam from the boiler through a normal or drop header, with an equalizer line to the top of the bulk tank and a pipe from the bottom of the tank to the inlet to the boiler, and your steam main running to the greenhouse and house (note, by the way, that this line would have to be very heavily insulated to avoid unacceptable losses in the pipe). Arranged that way, with the boiler providing steam and an equalized tank the system would run.

As drawn, at least as I interpret the drawing it won't.

neilc

maybe in the absence of air,
but it's easier to push air out at 2psi, than it is at 30, right?

leonz

How close are you to the Alberta coal fields WoodSteam_life?

Perhaps a coal fired steam boiler like the EFM DF520 with an H stamp or
an AHS S260 with an H stamp for steam heating would be a better option?

The western Sub Bituminous coal in Montana and Wyoming burn down to a
very low dead ash volume. The Sub Bituminous coal mined in Alberta would
work well in a pot stoker or a rolling grate type of coal stoker.

WoodSteam_life

Jamie Hall said:

As drawn, at least as I interpret the drawing it won't.

Yes Jamie, I am talking about steam, not hot water! I am not interested in radiant heat, I need to put steam radiators in the greenhouse as well as the house and without steam traps if it's a one-pipe system.

Why do you need a pump if I want steam to build up in the buffer tank? That tank is my battery, thermal deep cycle battery so that the boiler doesn't have to run around the clock wearing itself out. The idea is to generate enough steam to sustain the system. Yes the big tank would also hold hot water, but that water would be the condensate that returns from the main, not from the boiler. What is the point of pumping hot water into buffer tank if I need it to flash into steam? I cannot have my main run directly from a boiler riser, these boilers aren't designed for that, these are hot water boilers for radiant heat, but I do need to generate steam, and I need your help make it happen guys.

ChrisJ, the fast traveling dry steam has enough space in a 2-3" diam pipe to whistle around and yes it travels at 60 miles an hour at 0 psi, the higher the pressure, the slower it goes and the condensate gravitates towards the tank so long as vents are present and no micro bubbles are impeding every turn of the steam seeking the lowest pressure point.

leonz, I am not interested in coal, this is a firewood thread, a steam heating problem in need of a solution. I either modify an existing wood-fired system to flash into steam or I fabricate an actual steam boiler from scratch and hope I don't cause an explosion later.