Oli Heater that uses Waste Engine Oil

February 27, 2009 11:39 AM

What are the pros and cons of trying to switch heating systems from a traditional furnace to a waste oil heater that burns used gasoline engine oil, particularly for an automobile repair garage?

I work with small businesses in my city, and recently, two auto shops have raised the question of trying to facilitate the use of burning waste engine oil to heat their spaces. We live in Syracuse NY where the Winters are long and cold, and paying for oil can be quite expensive).

And p.s. if anyone knows of a good manufacturer, distributor, etc of these types of units, I'd love to know.

Cheers ~Frank
www.alchemicalnursery.org

posted by franklen to technology (10 answers total)

Check with your fire insurance carrier first. Some insurance companies do not cover them. One the other side of the coin, my local fire department uses a waste oil heater.
posted by Raybun at 11:59 AM on February 27, 2009

I was talking with someone who operates one of these and he had a bit of advice. He uses a separate heater to warm the bearings of the oil heater before firing it up. Apparently the bearings would need replacement frequently otherwise. Not sure who made the unit.
posted by exogenous at 12:12 PM on February 27, 2009

A very big con is the environmental impact, particularly on air quality. Here's a quote from a memo from the City of Toronto: According to the Ministry of Environment, a space heater burning used motor oil would emit 8,000 times more lead, 196 times more sulphur oxides, 128 times more arsenic and 35 times more inhalable particulate matter (PM10), than a space heater burning home heating oil.

Here is the Ontario Ministry of Environment's fact sheet on the practise.

There are probably many better ways of reducing heating costs for local garages (e.g. more insulation, air sealing, more efficient furnaces/boilers, heat recovery ventilation).
posted by ssg at 12:34 PM on February 27, 2009

Burning it is a bad idea.

Engine oil absorbs a lot of nasty stuff in fuel like sulphur, lead and other metallic elements. If the gasoline fuel was cleaner it might be okay but the trace metallic elements are nasty. Engine oil also accumulates lots of volatiles and harmful hydrocarbons (like benzene, phenols, etc.) that don't do you any favours when they burn.

People still do it but I wouldn't.

(I am an automotive combustion research engineer, but I am not your automotive combustion research engineer.)
posted by KevCed at 1:36 PM on February 27, 2009 [1 favorite]

Where the hell does the lead come from?

I understand a toxic soup of volatile organic chemicals coming from the blowby of gasoline burning and trace minerals, but why is lead 8000x home heating oil and arsenic is only 128x?
posted by morganw at 2:56 PM on February 27, 2009

Leftover lead from the age of leaded gas? Lead solder joints in the engine? Ancient Victorian pewter crankcases?

KevCed: Wouldn't all the random organic volatiles get burned as well, assuming the furnace is working properly, leaving just H2O + CO2 + toxic heavy metals going up the flue?
posted by hattifattener at 3:04 PM on February 27, 2009

Lead is used as an alloy in some parts and carried away by the oil as the parts wear out.
posted by exogenous at 3:06 PM on February 27, 2009

Gasoline has trace impurities in it. I'm not sure where they originate (i.e. from crude oil or acquired in the supply chain). I have read analyses of used oil and lead becomes "concentrated" in a sense as it accumulates from trace (ppb to ppm range) in the engine oil. Other metallic elements are also found, typically those are wear-related.

I think lead has been steadily decreasing but heavy metals are frequently found in waste motor oil. I think cadmium is another one that is used in certain exotic lubricants and it finds its way into the oil.

As for VOCs burning off, you have to consider that under ideal steady state conditions things would go nicely and all the nasty stuff would go up the flue, but wall-quenching, clogs, and transients can cause sub-optimal combustion. Some of the detergents, viscosity modifying compounds and other additivies (ZDDP for example) can play havoc with "expected"chemistry.

I wouldn't burn my used motor oil to save money.
posted by KevCed at 9:15 PM on February 28, 2009

Thank you all for your comments. So I am wondering what the comparison would be of pollutants over life cycle for burning motor oil vs. recycling it? That is some necessary info we need to make a determination here. Can anyone help with this?

Also, we are not talking burning in space heaters, but in engineered furnaces made for this. So I doubt if the toxics released would be as bad right?
posted by franklen at 8:33 AM on March 2, 2009

In the context of the sites I linked to above, space heater means furnaces, boilers, etc. I'm sure there is some variation from manufacturer to manufacturer in terms of the completeness of combustion, but no shop sized heater is going to burn all that cleanly. It doesn't matter what kind of furnace will be used, all of the heavy metals (particularly lead and arsenic) are going up into the air. Even if one heater is twice or four times as good as the average as far as particulate matter and sulphur oxides, those emissions will still be much, much higher than those from a heater burning heating fuel.

I have not hard data for you, but I would be surprised if a significant percentage of the particulate matter, sulphur oxides, heavy metals, etc. ended up in the air when oil is re-refined. Oil refineries are not the greatest thing environmentally, but they certainly don't just throw all their heavy metals into the air.
posted by ssg at 8:10 PM on March 2, 2009