quote:

John Galt writes:
That sludge is a valuable resource for me, as useful as the clear top oil. It's pumped out and mixed with sawdust from chainsawing fuel wood and packed into 1/2 gallon milk cartons. One of those in the woodstove first thing in the morning quickly warms the house right up to comfortable temperature, especially when it's 30 below. There's a lot of BTUs in a half gallon of transfat oil/fat soaked sawdust.

John and others doing this, do you find any difference in stove or flew cleaning after a season of burning WVO soaked sawdust or logs when compared to a season of regular wood burning.

John, are you taking about cardboard milk cartons or plastic ones?

I've been running these in my stove since the beginning of the season and there doesn't seem to be any more or less build up at this point and boy do they heat up the house fast and free, I haven't actually mixed the oil with saw dust yet but have taken all the food particles that fall to the bottom and packed them into the large half and half cardbord containers and in they go, thanx John, great idea, happy veggin'

Definitely wax coated cardboard milk cartons. Eight of them fit nicely in an empty cubie box [the cardboard part]. I use one sawdust/oil sludge brick on top of a well developed fire, and burn it with lots of combustion air. The design of the stove introduces combustion air through the baffle, and the fuel burns like a gas jet [point 4 on the drawing] with minimal chimney deposits. With this stove I found no increase in chimney deposits when I started burning oil bricks.
Pacific Energy Woodstove

DO NOT BURN VO WASTE IN A FIREPLACE

This message has been edited. Last edited by: john galt,

I burnt one of these 'bricks' made to Johns design in my slow combustion fire. It burnt so strong for so long I vowed to make them only half as big next winter.

I put them on the hot coals in the middle between two logs and them a log on top and they burn for a long time and hot, hot, hot!!!

This message has been edited. Last edited by: veggedout,

I use one sawdust/oil sludge brick on top of a well developed fire, and burn it with lots of combustion air. The stove does not get dangerously hot. About 600°F + on the single layer top, and about 300°F on the double layer sides and back, and a lot more than 600°F at the glass door. [My IR thermometer only goes to 600°F.] The top ranges from 550°F to over 600°F, and the door instantly maxes over 600°F. The single layer stack is 400°F at the stove and 200°F where it goes through the ceiling. These are normal temperatures for this stove with a well developed pine wood fire. I only recommend oil soaked sawdust bricks in an efficient air tight firebrick lined firebox stove with combustion air control. I heat the house with this stove, and an 'oil brick' in the morning brings the house temperature back to 70°F quickly.
Outdoor temperatures at this time of year are around zero °F.

DO NOT BURN VO WASTE IN A FIREPLACE

This message has been edited. Last edited by: john galt,

I've also been doing this. I posted the same idea-but with boxes about the size of a shoe box last March or April or so. I guess it didn't get much press on here because the coldest part of the year had passed.

I've developed a method to use oil and oil sludge. I never trust the last little bit of oil, so I wind up with buckets and buckets full of this stuff with nowhere to go but up in flames. I guess I could let it settle again, but free heat is attractive.

I've found that I prefer boxes that have a nice large top to them. I mix up my sawdust oil mixture in a 5 gallon bucket and pour it in. I can't imagine how tedious (or messy depending on method) it would be to fill a 1/2 gallon milk container. Although, that does seem like a good plentiful box.

The recipe I use is I fill the bucket with sawdust and shavings to the bottom ring. (I guess about 4 inches from the top.) Then I put in 2 quarts of oil, stir it up with a flat piece of wood, then dump it into a box.

I get my shavings and dust from a lumber yard that uses a huge radial arm saw for quick cross cuts. I think it has a 14 or 16 inch blade on it. So it makes meaty shavings more than fine dust. If you are using fine dust you will need mroe oil. Don't use too much oil though!!! I was using about a gallon of crappy oil to each bucket of shavings, but then my ash tray filled with black oilly sludge. It then leaked down the front of my stove and made a huge mess. So don't try to use too much oil.

As far as boxes go, my favorite boxes to use are boxes from 12 packs of beer bottles. I don't do much drinking, but whenever we have a party at work I take the boxes home.

I have tried just dumping piles of this mixture in the stove, but it doesn't burn as well as if I pack it into the boxes. It took a while to develop a theory as to why. Here it is. When it is packed into the box, it sits up higher, near the incoming air vent on my particular stove. It allows incoming air to shoot at it as opposed to traveling over it. This means more air. Also, perhaps more importantly, once the box burns away it stays relatively shaped like a cube. The vertical sides do a much better job of shedding burnt material to expose new unburned sawdust than does a pile. The pile approach tended to develop a pile of ash on top of unburned sawdust that would smother it enough that it would just smolder, but not burn with a hot flame.

I have experimented with making a mesh box that I could reuse. However, my first attempt was made of steel window screen using copper 14 guage wire to shape it. It lasted a few minutes before the screen got weak from the heat and fell apart.

I keep meaning to experiment with a heavier screening material like chicken wire or that stuff made from one sheet of steel that they slice strategically, then stretch. That stuff is tough.

I've been working a lot on this method in the last few weeks as I have been trying not to use the last bit of heating oil before I get my WVO boiler online. I finally got the boiler working on Saturday though!!! So hopefully no more trips to the lumber yard for huge bags of heat.

Stay warm!!

I need to try that. The snow is too deep to go down to my "veg pit" and the dregs are piling up. I guess I'll try the 12 pack containers since I usually have plenty of those around.
Sounds simple enough: mix w/ sawdust into box, then place box on top of fire wood?
I was reluctant to do this until I heard more about buildup in chimney/stove pipe, I burn around 3.5 cord/yr and clean my chimney every year. but it sounds like it is not a problem,
Thanks!.

been checking my flu pipe every week, almost no build up

Does anybody notice an objectionable smell outside the house when burning dregs in milk cartons? Steve

Are you asking if there is an objectionable smell, or if anyone notices it? I suppose some people might find the smell of barbecue objectionable.

DO NOT BURN VO WASTE IN A FIREPLACE

This message has been edited. Last edited by: john galt,

My wife objected to the smell outside. I was burning some oil dregs soaked up in kind of a mixture of sawdust and dirt that I just scraped up on the driveway. I should try again with just clean sawdust. Smoke from our fireplace sometimes swirls around and ends up near the front door.
Steve

Fireplace???

DO NOT BURN VO WASTE IN A FIREPLACE

Only use an airtight wood stove with a firebrick lining and controlled combustion air.

quote:

Originally posted by john galt:
...DO NOT BURN VO WASTE IN A FIREPLACE....

WHY! besides it not working as efficiently

I'm not sure exactly why John is saying that, but I have a few theories.

One is that once the box burns, if the sawdust mixture was not packed well enough, it can just fall apart, spreading burning sawdust everywhere. This could potentially leave the hearth if you have enough sawdust.

Another is that it smokes pretty heavily until it heats up. It's not pleasant smoke.

Third is that it burns really really hot, so being able to crank down the airflow is a good thing.

But John probably has other reasons.

Well, the risk of burning glycerin in a low temperature fire is the production of Acrolein.

Here is the wiki on Acrolein-

Acrolein is a severe pulmonary irritant and lacrimating agent. It has been used as a chemical weapon during World War I. It is, however, not outlawed by the Chemical Weapons Convention. Acrolein is also a metabolite of the chemotherapy drug cyclophosphamide, and is associated with hemorrhagic cystitis. Skin exposure to acrolein causes serious damage. Acrolein concentrations of 2 ppm are immediately harmful. Acrolein is a suspected human carcinogen.[4] [5] In October 2006, researchers found connections between acrolein in tobacco cigarettes and certain cooking oils and the risk of lung cancer.[6]

quote:
Originally posted by john galt:
...DO NOT BURN VO WASTE IN A FIREPLACE....

quote:

WHY! Big Grin besides it not working as efficiently

Bill covers them well.

VO sludge must be burned in an airtight high-temperature firebox with controlled combustion air. This is very high energy fuel, about 3x a piece of wood that size and it will burn about 3x faster.

Open Fireplaces are not safe for burning anything, and use more energy than they produce.

this thread brought up a good point about spontanious cumbustion.

Do you sludge log makers do it as needed or do you make and store them? If you store them what about spontanious cumbustion issues?

For example a properly sealed log.... without air, does this elliminate this problem?

What about packed a clear PVC tube to:
. watch the insides and see if the log begins to compost (break down)
. measure the temperatures inside to see if it raises like it will in composting

quote:

Originally posted by john galt:
... The reports of spontaneous combustion I'm familiar with all involve piles of cotton rags soaked with the oils used for wood finishing like linseed and tung.

There has been a few reports of rags of WVO that combusted here on this board.

None of SawDust that I recall but then again even though it is an old concept it is just now starting to take off.

John how about taking one of your logs and jabbing a meat thermometer into it and let it sit and write down the temps every 24 hours or so for a month? Not sure where best to stick the thermometer.