Author Topic: oil burners  (Read 7259 times)

38ac

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Re: oil burners
« Reply #15 on: June 12, 2018, 01:26:40 PM »
Bruce, I heat my shop full time with waste oil so it has to be safe. The devices you are describing are what is built into my Lannair unit. It has an Optical flame sensor. The over fire and fan circuits are handled by a regular old type mechanical  furnace fan controller like this, not very complicated nor costly. Probably should be part of any homemade unit and controlling the flow of oil?
Collector and horder of about anything diesel

BruceM

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Re: oil burners
« Reply #16 on: June 12, 2018, 04:04:03 PM »
Optical flame sensors (using an infrared photo transistor) depend on the enclosure and fire box design to be reliable- so that other sources of stray light or heat don't fool them.  Not cooking the sensor is also critical. Once well engineered into the design, they are long lived and reliable.  I found them difficult to integrate into the modified propane stove I was retrofitting...the oven pilot light I wanted to sense was in a very hot location deep under the oven when the full oven flame was on.   I was hoping that the large (1.5mm) glass fiber would allow me to keep the sensor at a distance but alas, the propane's blue flame light spectrum was absorbed by the glass fiber.  You can get IR flame detectors for Arduinos and such for a few bucks- but best to get them and play with them very early on so you can integrate them into your design.  The commercial optical sensors also often will use a lens system to that they can see a very narrow field of view- to help keep the sensor away from the heat. they will also use IR sensors in metal cans with glass windows- specially to handle handle high temperatures. So using a commercial flame sen$or might be a good idea.  For my convenience application (just wanted an indicator
to know that the pilot got lit without having to crawl on the floor and look), I couldn't justify spending a few hundred dollars.

I don't have the stones for DIY burners myself but enjoy reading about almost any DIY projects.  Using the safety gear from existing designs sure makes good sense to me.  I would study their safety features carefully and steal as much good engineering as I could.

Buying good engineering is smart.

« Last Edit: June 12, 2018, 04:11:30 PM by BruceM »

BruceM

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Re: oil burners
« Reply #17 on: June 12, 2018, 05:34:18 PM »
Just for fun I looked at a few companies making burners for waste oils of all kinds.  There is some serious engineering here.  38AC's Lanair is a high end, well known one.  Kingbuilt also makes them. Some research might find the best reviewed one for your desired waste oil fuel, then look closely at the design features it took to achieve that level of performance and reliability.  My personal impression is to be glad for my simple DIY solar single tank drain back hot water system, as a waste oil boiler is technically daunting. 






mikenash

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Re: oil burners
« Reply #18 on: June 14, 2018, 12:49:07 AM »
Alrighty . . . .

See this bloke here - see link below:

https://www.youtube.com/watch?v=SAmHNp6fOUA

I would like to have a play with something similar

His stove is philosophically similar to mine in that it has a grate, and has its main air flow from a secondary (ashpan) door below the grate, and has a flue set back and a bit indirect

My boss was away from the workshop for a couple of hours this morning so I knocked this up - see pics?  It's mostly 5mm/8mm stuff and might take a lot to get hot initially?  I guess we'll see?

The thinking isn't sophisticated in any way.  We have pipe and flanges and stuff lying around so I cut a 70mm slice off a piece of 200mm pipe (5mm wall) and welded it onto a flange with a 90mm hole in the centre.  Then I took a bit of 80mm NB pipe, drilled a couple dozen 13mm holes in it (a pure, unadulterated guess - I can always drill more or weld some up later), welded a cap on it out of a bit of 8mm plate, and welded that onto the aforementioned flange

I'll stick it out in the yard later with a half a litre of kerosene in it & give it a burn to see what it does.  if it doesn't appear to do anything inherently dangerous then I'll clean the ash and charcoal out of the woodstove and stick it in there to see what happens . . .

In THEORY, if I plonk that on the grate, block the rest of the grate off nicely with some 3mm plate that's lying around and start a fire in it with some kerosene, open the ashpan door wide and close the firebox door tight, then maybe the draft will "draw" up through the 90mm hole in the bottom and, thence, through the holes in the little steel tower . . .

If that works OK I'll introduce a crude-but-controllable drip of oil . . .

If I'm lucky the wee tower will get hot enough to "vapourise" the oil that drips into the pan and the draft MIGHT be right enough to burn that vapour - to some extent or another . . . .

If that works - then I guess it's suck-it-and-see.  if it doesn't work - then I guess it's plan B

From my POV it doesn't have to be very good to be a "success".  If I have a winter's day pottering about the workshop, and could keep it warm & generate hot water by burning waste oil rather than firewood - well that would be good

Challenges around metering, finding a way to maintain a constant "oil pressure", safety , how much fiddling it might need IF it does work . . . .well, some of them might be fun?

Once again, there's a wealth of experience here on this site - I'd appreciate any comments or thoughts based on experience

There is a million videos on youtube of burners with a "pot", below a "diffuser, attached straight to a draft/flue, and they seem to generate a LOT of heat.  I'm not sure one would fit in my woodstove  . . . but if that's what it takes, then that might become plan B.  But for the meantime - I'll have a go with this

Cheers


ronmar

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Re: oil burners
« Reply #19 on: June 14, 2018, 06:12:19 AM »
Things I have learned in my experiments:  I am also looking for small output and simple.
I dont think overtemp is a problem, in fact you need red hot temps to completely crack the gas for a clean burn.  Particulary important if you are trying to heat water as an unclean burn will quickly condense on your heatex.  I have found the hotter the burn the less carbon also as the high temp the heavier the oil you can crack.  I believe that burning oil is basically like refining it.  The lighter portions vaporize and burn at lower temps leaving an ever thickening base that requires a higher and higher temp to completely consume.

The minimum chimney I have been able to burn consistently with is about 7’ problem is getting adequate turbulence, and it is a fine mix between getting primary air and secondary air in the right place with the right proportions. I would like to heat water also but a larger chimney might be a problem so I may shift to a fan/blower configuration to keep it copact and experiment with that.

Moisture content is the biggest variable and will really confuse things as it only takes a little moisture vaporizing to remove more heat than you can create. 

I actually have a fuel design I have built that seems to be pretty foolproof.  So far I have only configured it for batch burns of about 1qt but it solvs the inconsistencies and hazards of drip feed and it has no moving parts(except the fuel of course). Since it only feeds fuel as it is burnt, it cannot overflow if it flames out. Its only issue has been with the introduction of large ammounts of water. When it reaches the vaporizer it of course boils and can cause some oil to escape thru the air inlet.  But since it is such a small burner the catch pan it sets over easilly contained the oil, some of which burnt briefly.  If this was in a contained unit it would not be a problem as the products of combustion would be pulled right thru the burner by the draft.
PS 6/1 - ST-5.

ajaffa1

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Re: oil burners
« Reply #20 on: June 14, 2018, 09:09:17 AM »
Hey Glort, I think you and I are thinking along the same lines. Having a generator that burns WVO looks like the way forward. Utilizing the waste heat from said generator to provide hot water and heating/cooling to your home looks like a win win to me. I was wondering about building a system with a power shaft with pulleys for generator head, compressor, air conditioning, water pump, hydraulic pump and etc. I was wondering if anyone had ever tried using car wheels/tires as a means of transferring power from a flywheel on a drive shaft to a flywheel on a generator. pump and etc? I am thinking of a tire mounted on a lever with a spring to provide the required contact pressure. Might work well as a means to couple my CS to the drive shaft, might also help with the flicker a lot of people experience with single cylinder diesel generation. A tire could also be partially filled with water to provide extra flywheel mass.

Bob

ajaffa1

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Re: oil burners
« Reply #21 on: June 14, 2018, 09:41:05 AM »
Further to my last post I could build a system that would generate DC electricity to power my grid tied inverter. This would provide me with the electricity my home needs during the evening and also export any surplus to the grid. As far as I know grid tied solar systems aren`t limited to the hours of daylight. So I could end up with them having to pay me rather than the other way around. :laugh:

Bob

mikenash

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Re: oil burners
« Reply #22 on: June 14, 2018, 06:54:51 PM »
Couple of thoughts fwiw:

That tyre drive is widely used in the timber industry; but only at low low speeds - you might have balance issues at higher speeds?  Where we have used tyres to drive timber roundtables I have fitted forklift tyres for their small size and rigidity

Shaft and bearings?  Unless you get it exactly exactly right, more than two bearings on a shaft can be asking for trouble with mis-alignment and premature bearing failure.  imho a heavy shaft and just a couple of bearings might serve you better?

just my $0.02.  Cheers

ajaffa1

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Re: oil burners
« Reply #23 on: June 14, 2018, 11:18:23 PM »
Yep, I think the line shaft is a go. Used a lot of them when I worked as a maintenance fitter in a sawmill. Mike is absolutely right about having more than two bearings for two reasons first the alignment has to be spot on or you will either break the shaft or get through a lot of bearings. The second reason is that where I worked we had six meter long shafts with multiple bearings and pulleys, every time a belt broke we had to undo all the bearings to fit a new one. We took to fitting ten belts to each pulley at a time, one fitted to the pulley with nine cable tied to the frame to use as spares.

This problem was my reason for suggesting tires. The RPM of the tire is determined by the diameter of the pulley on the line shaft so for example with the shaft doing 600 rpm and a 200 mm pulley, a regular car tire would be doing less than 200 rpm.
The smaller the pulley and the larger the tire the lower the rpm.

Hydraulic pump is on my wish list to drive a press and broaching tool for cutting keyways in pulleys. It will also be connected to a log splitter, too old for that sort of sh1t now.

Probably go with your 240 volt AC suggestion and then rectify it. Been searching for a suitable head for ages. I did discover that Gasweld sell a range of generator heads in Australia, sadly no pictures just descriptions and prices.

I believe I should build the set up near to the house, this would enable harvesting of heat for hot water and etc. Not sure how to overcome the noise to keep the wife happy.

Bob

mikenash

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Re: oil burners
« Reply #24 on: June 15, 2018, 12:00:15 AM »
 +1 there Bob

I remember very well the clusters of belts all cable-tied together along the shafts, and the old pillow blocks that had craked their housings and were now held down with a bit of flat bent into an arc over the top of whatever remained of the cast block & bolted down

One thing we did that I really like, though, was we standardised the outputs of most of our reduction drives to things like conveyors and just put an A40 bet on a couple of pulleys as a fuseable link.  Often the smell of fried belt - or the puff of smoke - would alert you that some monkey had jammed a belt even before anyone had noticed the timber had stopped flowing - we got extra good at changing them in seconds.  A $4 belt was much better than a $2400 drive as a sacrifice to the Gods of Stupidity

BruceM

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Re: oil burners
« Reply #25 on: June 15, 2018, 12:16:51 AM »
Regarding sound, that has been a big issue to me because of brain damage and hyperaccusis, and it is what made me choose the Listeroid from my off grid prime mover.  I now think exhaust noise is a snap to eliminate via a "leachfield" type earth muffler that we used on my neighbor's setup.  The other noise (intake and mechanical) is much less but tougher- you need sound absorbing baffles for the engine room air.  At say 5KW and up, the use of a sound baffled squirrel cage blower (and sound baffled inlet) might be a good way to go. Avoiding a thumper would help with the subsonics.

Distance for hot water runs is expensive in foam board and spray foam; my home and shop are separated by 50 feet and that cost me a total $1500 in foam and labor to do.  After that one time expense, there is very little energy cost for moving modest volumes of water around; I originally did just fine with a 10 watt pump for the in-floor heat. (Now I use a 20 watt pump since it's no longer a closed loop.)  I made a 4" thick EPS foam box in the ditch, laid in the pipes, and then filled it with spray isocyanurate foam a bit over 6" on top.   I was serious about not loosing energy to the earth in winter and my house needs little so a smaller BTU loss would have been a significant percentage.

A generator close to the house both saves and costs in comfort and noise/vibration control.  The leach field muffler also helps with the problem of exhaust near the house- you can direct it away in the least likely wind direction; very little odor is present in the cool air leaving the leach field via perforated leach field pipe and stack.




ajaffa1

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Re: oil burners
« Reply #26 on: June 15, 2018, 09:22:34 AM »
Hey Glort, take a look at this; https://www.gasweld.com.au/catalogsearch/result/?cat=0&q=alternator

Several on offer, sadly no pictures. I suspect those labelled as "taper" will be a single bearing. there are a couple that are not "taper" including one three phase. If its just down the road go take a look and report what you find, PLEASE.
Bob

ajaffa1

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Re: oil burners
« Reply #27 on: June 15, 2018, 11:02:36 PM »
Oz Listeroids used to sell them at a very reasonable price, I wonder where he imported them from. While the website is still up I believe he has retired and is no longer trading. I emailed him, a while ago, looking for spares but got no reply. Might pay him a visit next time I go to Coffs harbour.

Bob

ajaffa1

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Re: oil burners
« Reply #28 on: June 16, 2018, 09:34:38 AM »
Hey BruceM, I`ve been giving a lot of thought to the issue of noise, where I live there isn`t any unless you count birdsong. Occasionally I get rudely awakened by my rooster or one of my few neighbours decides to mow the grass or cut some firewood with a chainsaw.

I have two 25,000 litre concrete water tanks behind my house and I am thinking to build my engine shed behind those in the hope that they will absorb/deflect a lot of the noise, while keeping the length of pipework and cable to a minimum.

I would dearly like to use the heat, from running my CS, to heat hot water for showering and etc. When I lived in the UK, domestic hot water systems came with a built in copper coil which was connected to your gas/oil fired boiler. An electric immersion heater element was also included for summer/emergency use. Here in Australia most systems are electric only, there are some that have a built in coil for evacuated tube solar heating but I doubt that would be adequate. I am also not convinced that a thermo syphon system would work given the distance to the house.

I have thought about a pumped coolant system but that just adds to the cost, complexity and is an open invitation to the f*ck up fairy, perhaps I should move the hot water storage into the generator shed and use the existing water pump to transfer hot water to the house. An extra 10 metres of pipe work, so the hot tap takes longer to run hot. I could run it on an insulated loop with a bronze pump, this is the system used in high end hotels which guarantees instant hot water at every bath, shower or tap.

Got to go, supper pending.

Bob

ajaffa1

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Re: oil burners
« Reply #29 on: June 16, 2018, 12:32:17 PM »
Hey Glort, yes I think you are right: identify the outcome required and then work backwards from there. I do not require the CoGen to heat the home, we have a wood burning stove and enough dry logs to heat a village.

I think what I require is a totally reliable system that gets me off the grid. I have a very successful solar set up that has taken my electric bill down to $300 to $350 per quarter. I also have the advantage that there are no charges for water of sewerage, the annual council levy on my property comes in at just over $800 per year. So, like yourself, I am a bit of a tight arse. I don`t like having to pay people or organisations to do what I can do for myself.

I have been building a shade house for my wife's bromeliad collection with the intention of turning her hobby into a viable business. Rare/new variety broms can cost hundreds of dollars!

There is a 20 meter deep valley behind my property which narrows at the bottom end I would like to turn this into a many mega litre dam to allow us to irrigate, produce our own food all year round and be independent of the supermarkets. catchment for that dam would be around 5 acres, when it rains here there is a river running down that valley.

I think the problem I have is that I have too many projects and only one pair of hands, compounded by my health issues.

So in summary what I am looking to build is something so simple and reliable that my wife can operate/maintain it when I am gone. We export energy to the grid during daylight hours so we only need a system that will pick up the slack during the evening, until we go to bed. The biggest loads are electric oven and electric water heating and AC on very hot days. A CS 6/1 run on WVO should be able to do this easily provided we don`t try to run all three at the same time. When we are generating solar power the primary use is heating hot water, anything after that goes to the house/workshop, whatever we don`t use gets exported.

My CS is ready to reassemble, I have about 80% of the bits to do it. I`m just not quite certain of the best set up to get the best bang for my limited bucks and life expectancy. I`ll give you an idea of the issues I am considering: an air conditioner converted to be belt driven off the primary mover is going to be much more efficient than one run off electricity generated by the PM. The same applies to pumps, compressors and etc. It`s much easier to do everything electrically but the losses are significant and as I said earlier I`m a tight arse.

Bob