Diesel exhaust... good or bad for you? - PeachParts Mercedes-Benz Forum

JHZR2 · #1 04-16-2003, 06:29 PM

Hi,

I need to do a project for a green engineering class, in which I am going to focus on the diesel trucking industry, with regards to its pollutants, pollution control, future of the process (diesel engine), etc. I can find a lot of things from the EPA saying that diesel exhaust causes lung cancer, but I am having a hard time finding good things about diesel. I know there are a lot of sites out there praising diesel (the warden's article for example is a good one), and also articles arguing the EPAs claim that diesel exhaust is carcinogenic, etc.
I know I used to find a lot of articles liek this, but after searching for a while, I am only finding the bad stuff.
If anyone has any links they can think of or know of off the top of their heads, Id really appreciate having them posted here.
I think I happened upon articles like those which Im looking for previously because I didnt have any real search in mind, so I stumbled on them. Now that I need them, I cant find them, but they would be really useful to get the full story on diesel for my project.
Any help is most appreciated.
Thanks

JMH

#2 04-16-2003, 06:43 PM

Diesel exhaust isn't the best stuff to breath in, but I believe that it doesn't have a lot of the green house gasses that gasser's exhaust has. Diesels are also much more effiecent than gassers, so they don't require as much fuel

#3 04-16-2003, 06:47 PM

I wasn't giving this my rapt attention, but last night on CNN, there was a story about the feds releasing a study yesterday claiming that off-road diesels(farm tractors, boats, etc... i guess) were the number one source of greenhouse gasses. again, I was not paying close attention to this , but I bet if you look in CNN's archives for yesterday, you will find what I speak of. Good luck.

The Warden · #4 04-16-2003, 07:04 PM

Check out the "Why are diesels better?" link in my signature. I wrote an argumentative essay on diesel versus gas a few years ago, for a class. Got a perfect score on it, too.

The link is the text of the paper. AFAIK, all of the data's still valid.

Hope it helps some...good luck!

#5 04-16-2003, 07:17 PM

One of the stories said the EPA is not so sure about the degree of harm coming from diesels exhaust. Main reason cited is that diesel exhaust is heavy enough that it does not become permanetly airborn, as most burned hydro-carbons are known to do.
They also noted the exhaust particles drop to the ground and could polute the water adn so on.
Sorry but I cannot point you to the source on that one.

psfred · #6 04-16-2003, 08:58 PM

I can't give you a link, but what you need to look for are comparisons between diesel and gas engines on unburned hydrocarbons, NOX (nitric oxides), particulates, and carcinogens.

Diesel smoke contains considerable amounts of benzene and derivatives, all known to cause cancer, and carried in breathable particles. Part of this is due to poor combustion, part to the nature of diesel fuel (the benzenes are already there in relatively high concentrations.

However, when the soot is gone, so are the carcinogens, and automotive/truck diesels are MUCH better in this reguard than they were just 20 years ago. I cannot see ANY smoke behind my 300D, even at night, and I've never even seen smoke marks on a VW TDI!

Off-road vehicles tend to have ancient technology (1950s and 1960s), use huge amounts of fuel, and make smoke like there is no end to it because the manufactures (american, mostly) are bone idle when it comes to research and design. They pollute a LOT due to low compression engines, wear and tear, and dirty cheap fuel with gobs of sulfur in it. None of this in an inditment of diesel equipment, just the result of the typical laziness and cheapness when it comes to machinery in America. The operators will be nearly stunned when they find out how much better the new equipment is (and how little fuel it uses) when someone finally beats the owners into buying something of newer design than 1965!

As far as pollution from engines goes, the typcial automobile is now very clean, and getting cleaner. To the point that LA improved air quality dramatically by outlawing gasoline lawn mowers -- the typical gas lawn mower in S. Cal. made more unburned hydrocarbons and smog mowing a quarter acre lot once than all the cars in the family produced during a month of driving......

Peter

Ken300D · #7 04-16-2003, 09:08 PM

Japanese diesel machinery seems to operate much cleaner than American equipment. Maybe the cleanliness is a byproduct of having to come up with an efficient design to burn the fuel completely - expensive fuel in Japan (and Europe for that matter).

Is off-road diesel refined differently? I thought it was all the same, just taxed differently. In fact, I thought diesel and heating oil was essentially the same. Are there different refining rules for on-road diesel?

Ken300D

kerry · #8 04-16-2003, 09:22 PM

You need to factor in the benefits of biodiesel and renewable energy sources compared to non-renewable. I recall reading a numberof years ago that Brazillian diesels ran mostly on biodiesel.

There was an article in today's Denver paper about the EPA's new regulations on off-road diesels.

Don't forget that all these judgments are relative. What are the alternatives and what kind of costs are associated with them?

psfred · #9 04-16-2003, 09:32 PM

Kerry:

The costs and benefits are exactly the same as for automobiles. The off-road equipment has not been regulated AT ALL, while emission from automobiles has been since 1962. The EPA just outlawed draft tubes on diesel trucks a couple years ago -- your "friendly" trucking lobby at work.

There is enough off-road equipment out there to have a substantial impact on air quality, believe me!

Fuel consumption and sound level are both very important to Japanese equipment makers -- not only will the Japanese not buy anything but very quiet cars, noise levels are very striclty controlled, else the entire nation would be deaf by now.

Off-road fuel is not regulated for sulfur content, road use fuel is. Ir will have the sulfur content reduced considerably in the near future, too.

Peter

Capt Kirk · #10 04-16-2003, 11:16 PM

http://www.northtexaspowerstrokes.com/post/Diesel%20Engines%20and%20the%20American%20Automotive%20Industry.html

EDIT:
Hmmmm, wow I didn't know Warden that you wrote that. Good Job on it.

Dana B. · #11 04-16-2003, 11:39 PM

For a diesel industry perspective, try www.dieselforum.com

DieselAddict · #12 04-17-2003, 02:25 AM

JHZR2, the Chevron website has a great deal of interesting info on diesel fuel and diesel engines. Some good info is also on the TDI club website, especially in the FAQ.

http://www.chevron.com/prodserv/fuels/bulletin/diesel/
http://www.tdiclub.com/

To put it briefly, a diesel engine, compared to a gasoline equivalent, has better fuel economy, usually more torque and less horsepower, lower CO2, CO and hydrocarbon emissions, higher NOx (oxides of nitrogen) and particulate (soot) emissions, and usually is more durable. Not to mention it has a very cool sound.

As you may see from my signature I also have a Civic Hybrid which has a small gasoline motor and an electric motor that acts like an electric turbocharger and is self-recharging. No doubt the cleanest car you can drive, but it clearly shows the inefficiency of the gasoline motor when you look at the Jetta TDI and notice it gets about the same fuel economy with a plain-old diesel engine. By the way I enjoy driving the Benz more than the Hybrid.

#13 04-17-2003, 11:36 AM

Diesel's weaknesses have more to do with the poor fuel quality that we have here in the states. Diesels are cleaner than gasses on HC, CO, and CO2 emissions without catalytic convertors. They are higher in particulates, NOx, and for now, SO2 emissions.

Despite the higher particulates, they are indeed heavier than the microscopic particulates emitted by gasoline engines, and do fall out of the atmosphere. Changes in fuel quality regulations will help correct the other issues with diesel engines. The new regs will also open the doors to add exhaust aftertreatments to further cut emissions.

Of course, no engine exhaust is good for you. What the environmentalists don't tell you is that gasoline exhaust contains all of the same cancer causing gunk in it that diesels are alleged to.

samiam4 · #14 07-30-2005, 03:23 PM

One thing not mentioned here..

While it is fine and well to talk about NOX and green house gases. Brass tacks is how many tons of this stuff does your car put into the enviroment in a year. Also, it would be better if we used less of non-renuable resources.
In the USA, looks like according to the EPA site, the honda hybrid wins. But, I must say the TDI's are bigger and can haul more stuff.

Michael

t walgamuth · #15 07-30-2005, 04:52 PM

and diesel are pretty much the same. i hear. fuel oil (hho) is i hear pretty much the same as #1 diesel.

earlier this year i sold 2500 gallons of it to a friend who has heavy equipment. i found it in the tank in the basement of my 1913 building which has been using natural gas for at least 30 years. he used it in his equipment with no adverse affect. i also ran one tank of it in my 350sdl. ran fine.

unscientific but known info.

tom w