I have an idea for a boiler...what do you guys think

I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Sat Feb 22, 2014 6:43 pm

I've been tossing around this idea for a boiler the last couple days and decided to draw up some preliminary sketches to get your guy's oppinions. Let me add this disclaimer I didnt go to art school so don't pick on my sketches to much and I'm not trying to redesign the wheel just alter it a little bit to suit my needs. I got the idea from burning in my clayton furnace If I got a real hot bed of coals I could mostly bury them with wood chips/debris even being wet off my firewood processor and after a brief bit of intense smoke it would light up and eventually turn the whole bed into hot coals and give off a lot of heat but it wouldn't last but maybe a half hour and then would need refill. So I started thinking off how I could refill it automatically. I knew a auger wouldn't really work because you need a consistent size and wood chips are rarely that so I came up with this idea. The storage hopper sits above and to one side of the main chamber and has a chute that comes down and dumps onto the top of the bed of coals. It will have two electric actuators to open a flap on the bottom of the hopper and dump some wood chips on the fire. There will be a second spring loaded flapper in the chute that the wood chips will push past and then will close to keep smoke and sparks from going up to the hopper. The main part of the stove will be similar to my clayton only bigger and wrapped in a water jacket. It will have a shaker grate system and im contemplating hooking to another actuator so it will shake itself every so often into the ash pan below. The hopper actuators would either be a on a timer to open every so often or if I can figure out how on a thermostat. Let me know what you think?

This is the side view
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this is the front view
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Re: I have an idea for a boiler...what do you guys think

PostBy: franco b On: Sat Feb 22, 2014 10:03 pm

I like the idea that you want to design something. I don't like the intense smoke. As in a pellet stove wood burns best if fed in very small batches and frequently. Your feed will have to be a measured small quantity like a cup full timed to burn well before the next cup full. I don't think it easy to design the feed and stop part without jamming on the chips.
franco b
 
Hand Fed Coal Stove: V ermont Castings 2310, Franco Belge 262
Baseburners & Antiques: Glenwood Modern Oak 114
Coal Size/Type: nut and pea

Re: I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Sat Feb 22, 2014 10:29 pm

franco b wrote:I like the idea that you want to design something. I don't like the intense smoke. As in a pellet stove wood burns best if fed in very small batches and frequently. Your feed will have to be a measured small quantity like a cup full timed to burn well before the next cup full. I don't think it easy to design the feed and stop part without jamming on the chips.


Where I live the smoke wouldn't be much of an issue pretty rural and the neighbors burn wood so I don't have to worry about making anyone mad or smothering someone in smoke. But even that clayton if it was good and hot would only smoke intense for 5-10 minutes and then it would clear up. It would burn across the top layer and then once that burned up it would start coaling up nice and hot red coals and put off some immense heat and it was using a waste product which is what I really like. And I can get wood chips and material to make wood chips by the hundreds of tons for free or almost free( lots of logger and sawmill friends) so efficiency isnt so much of a concern( burning twice as much free stuff is cheaper then half as much of something I have to pay for). The wood chips jamming the flapper open was also a concern because I didn't want the fire getting into the storage hopper that's why I came up with the second flapper I figured even if it jammed open slightly the chances of a spark getting past two flappers without cooling off was minimal. Its definatly going to need some refinement thats why I was looking for opinions so I thank you for your input. The control is something I have to figure out because wood chips are kind of an all or nothing deal cant really let the fire die down to much or there wont be enough to start the next batch so I was thinking of just putting it on a timer opening the flapper every 5 or 10 minutes and dumping some. What do you think?
Justify008
 


Re: I have an idea for a boiler...what do you guys think

PostBy: franco b On: Sun Feb 23, 2014 12:14 am

Yes. A timer is the only way to go but it must be a measured amount.

If the wood in the hopper is subject to heat for too long it could start to burn without any sparks, as long as it has some air. Even without air it could start to give off gas.

Rather than just dumping chips on a coal fire why not design a chips only boiler. Burning clean means more than no annoyance from smoke. There is also creosote danger in the chimney and added maintenance to the boiler to keep it and smoke pipe clean.
franco b
 
Hand Fed Coal Stove: V ermont Castings 2310, Franco Belge 262
Baseburners & Antiques: Glenwood Modern Oak 114
Coal Size/Type: nut and pea

Re: I have an idea for a boiler...what do you guys think

PostBy: Freddy On: Sun Feb 23, 2014 6:18 am

Justify008 wrote:the chances of a spark getting past two flappers without cooling off was minimal.


The chances must be ZERO. I think having the hopper above the fire is a bad idea. The hopper should be below the fire and the chips pushed up over a ledge to drop into the fire.

The idea of burning green..... only if you are desperate. Always dry wood before it's burned. It doesn't cost a thing to dry it, other than time. Dry wood burns with efficiency, wet wood doesn't. Dry wood makes much less creosote, wet wood makes a dangerous mess.
Freddy
 
Stoker Coal Boiler: Axeman Anderson 130 (pea)
Hot Air Coal Stoker Stove: Reading piece o' junk in the barn (rice)
Coal Size/Type: Pea size, Superior, deep mined

Re: I have an idea for a boiler...what do you guys think

PostBy: titleist1 On: Sun Feb 23, 2014 8:59 am

what is the range in size of the wood chips? the immediate thought i had was to make sure the fuel is dry because if it is damp it will bridge.

if you are using a timer to open the flaps, then set them up to open at different times by a few minutes. Then the spark cant get any further up the feed than the area past the bottom flap since the bottom flap never opens until there is fuel behind it and the upper flap stays closed for a few minutes after the bottom flap closes.
titleist1
 
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite

Re: I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Mon Feb 24, 2014 3:06 pm

So maybe something like this. Quick sketch the hopper would probably be closer to the stove since I can only find max 24" actuators with a quick search. But in this plan the chute would be at an upward angle towards the stove and the actuators would be in like a shielded box so when they push up it closes the hopper off and pushes the chips up and into the burn chamber. Have a flapper on the top of the chute that pushes open. And then would just close when the ram retracts. And benefit of this is it would be more controllable and measurable since only so many chips can fit in the chute. And no heat or sparks travelling up to the chip box. What do you guys think?
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Re: I have an idea for a boiler...what do you guys think

PostBy: titleist1 On: Mon Feb 24, 2014 5:23 pm

It kinda reminds me of the verti-flow stoker on the harman's. The stoker operation starts about 40 seconds into the vid.

http://www.youtube.com/watch?v=SQOkiS9Peq0
titleist1
 
Hot Air Coal Stoker Stove: Harman Mag Stoker (old style) one in basement, one in workshop
Hand Fed Coal Stove: Harman Mark III on standby for long power outages
Coal Size/Type: Rice/Anthracite; Nut/Anthracite

Re: I have an idea for a boiler...what do you guys think

PostBy: franco b On: Mon Feb 24, 2014 8:16 pm

Justify008 wrote:So maybe something like this. Quick sketch the hopper would probably be closer to the stove since I can only find max 24" actuators with a quick search. But in this plan the chute would be at an upward angle towards the stove and the actuators would be in like a shielded box so when they push up it closes the hopper off and pushes the chips up and into the burn chamber. Have a flapper on the top of the chute that pushes open. And then would just close when the ram retracts. And benefit of this is it would be more controllable and measurable since only so many chips can fit in the chute. And no heat or sparks travelling up to the chip box. What do you guys think?
I like it. You still have to design a proper burn chamber and like Freddy says, no green wood.
franco b
 
Hand Fed Coal Stove: V ermont Castings 2310, Franco Belge 262
Baseburners & Antiques: Glenwood Modern Oak 114
Coal Size/Type: nut and pea

Re: I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Mon Feb 24, 2014 10:10 pm

I like versatility of being able to still burn firewood or coal if I run out of chips. Plus I know I can get an 10+ hour burn on wood, the chips are limited to the size of the hopper so if im going to be gone for a long time and the hopper isn't big enough to last I can burn wood and set the chips to kick on x amount of hours after leaving?. It's going to be a lot of trial and error but the design of the clayton firebox burns all those things well so I was starting my design from there instead of from scratch. If I get a chance ill get a video of the clayton burning chips. And I wouldn't burn green wood it would be seasoned but I've never dug into a pile of wood chips that wasn't wet on the inside. If I can get it to work maybe a chip dryer would be the next build :gee:
Justify008
 

Re: I have an idea for a boiler...what do you guys think

PostBy: Sting On: Tue Feb 25, 2014 8:53 am

Install a Garn for the wood - a coal boiler for the Magic black rock - and a resistance boiler for freeze burst protection

Pipe it all together with proper isolation and control

Send the energy to the load

Done!
Sting
 
Other Heating: BurnHAM=NG-gas

Re: I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Tue Feb 25, 2014 4:37 pm

Sting wrote:Install a Garn for the wood - a coal boiler for the Magic black rock - and a resistance boiler for freeze burst protection

Pipe it all together with proper isolation and control

Send the energy to the load

Done!


I thought about getting a thermo control wood boiler and an efm coal stoker but that's 2 boilers to maintain and pay for upfront. Plus I sell firewood so if I'm burning firewood thats money out of my pocket if I can burn a waste product that normally just rots away that saves money. Plus I need a project to occupy my spare time or I start getting into trouble :D
Justify008
 

Re: I have an idea for a boiler...what do you guys think

PostBy: Bhvacr On: Tue Feb 25, 2014 5:36 pm

I think Hardy had an OWB similar to what you are looking to do... I know they definitely made one that runs on sawdust... It had a small 3 or 4" auger that fed the sawdust into the burn chamber... I don't remember if it would do the chips you are looking at using or not... it has been a long time since I worked on it last. Just a thought. Might try some internet searches on it.
Bhvacr
 
Stoker Coal Boiler: Looking at Alt Htg S260

Re: I have an idea for a boiler...what do you guys think

PostBy: Justify008 On: Thu Feb 27, 2014 6:17 pm

Bhvacr wrote:Might try some internet searches on it.


I've been researching them for a while but there are very few out there. All the ones I found were overly complicated or very expensive. What thickness steel do you guys think should be used for the burn chamber and for the water jacket? Maybe 1/2" for the chamber and 1/4" for the jacket hows that sound? I'd rather spend the extra now and build something that will last then try and skimp on steel and have to rebuild it. Is there any negative effects from going with thicker metal like if 1/4" was sufficient on the chamber would 1/2" be a bad thing like effect heat transfer?
Justify008
 

Re: I have an idea for a boiler...what do you guys think

PostBy: Sting On: Fri Feb 28, 2014 6:02 pm

10 gauge will work -- for a while :D

opps - I bet you now understand what I think of your idea

Kind Regards
Sting
Sting
 
Other Heating: BurnHAM=NG-gas