Coal Plant SO2 effects on handtools

[Tony Wilkins]

As an outgrowth of my problem with my LN bronze plane, it was suggested on other forum that it could be a sulfur problem - possibly related to a coal plant nearby that doesn't have an SO2 scrubber. Anybody know the effects of SO2 on ductile iron and Maganese Bronze?

[Jim Koepke]

As an outgrowth of my problem with my LN bronze plane, it was suggested on other forum that it could be a sulfur problem - possibly related to a coal plant nearby that doesn't have an SO2 scrubber. Anybody know the effects of SO2 on ductile iron and Maganese Bronze?

Dr. Google is your friend > effects of SO2 on iron < brings up a lot of information on the subject.


Findings – The obtained data showed that the corrosion rate of the studied metals increased with increasing rH. The corrosion rate of the metals decreased with exposure time, due to accumulation of corrosion products over the surface of the metals. However, the surface films of corrosion products on the metal surfaces were not stable and the corrosion rate increased again with time when the surface film disappeared.

Some downloadable studies.

jtk

[Stew Denton]

Hi Tony,

To start with, I can't imagine a coal fired plant that does not have an SO2 scrubber. In this day and age, and especially in a state like Texas, this does not happen. Such a plant would have been shut down YEARS, EVEN DECADES ago by the government.

If you look at the sulfur content of most types of coal, and I have but it has been a few years ago, it is quite high, on the low few percents levels. Our environmental laws are such that fuels such as coal, that have high sulfur content, would never be allowed to be burned in an a coal fired power plant without scrubbers.

That said, IF you had high levels of SO2 from an un-scrubbed coal fired power plant, and you don't, what happens with SO2 emissions is well known chemistry. What happens is that the SO2 rapidly finds moisture in the air and reacts with it to form sulfurous acid. (H2SO3) This is VERY RAPIDLY oxidized by oxygen in the air to sulfuric acid. (H2SO4) Sulfuric acid is a very strong acid, and with any moisture available, will readily attack iron, mild steel, etc. It will similarly attack copper. Sulfuric acid has a very high affinity for water, and even in dry west Texas, it will find some. (Sulfuric acid is battery acid.)

If you had continuous emissions of high levels of SO2, and you would if you had a coal fired plant with no scrubbers, you would find that everything near, made of mild steel, would undergo significant corrosion. Look at old photos of the rust belt factories in the years before good control of SO2, all of the steel on the factories in the whole area is rust brown. People would be seriously affected by the SO2, which is extremely toxic. Your throat would burn, your eyes would burn, etc. I have been around SO2, I've done reactions with it, used it in standards, handled cylinder of multiple gallons of it, have analyzed flare line gasses multiple times, have analyzed stack gas emissions with SO2 present, have worked with SO2, and have been downwind when SMALL amounts of SO2 were being accidentally emitted from stacks, etc. Years ago I ran a certified industrial environmental lab. Because of what I do for a living, and have done for many years, I know of what I speak. Believe me, there are no un-scrubbed coal fired power plants near Lubbock.

If you did have an SO2 problem, it would be extremely obvious, and people would be screaming for the state government to do something.

However, back to your question, if there was much SO2 in the air, all of your steel and cast iron tools would be covered with rust, especially susceptible tools like hand saws, files, etc. would be rusty, especially where there are finger prints on them. Files are especially susceptible, and files in a lab are usually rusty beyond the point of usefulness. For this reason, I make cardboard sheaths for files I use in our lab, coating the paper with 3 in 1 oil, motor oil, or WD 40, etc., and keep the files in them to protect the files. Copper would be covered with blue or green corrosion. It would be very bad.

I am not sure what issues are causing your problems, but it isn't SO2 from an un-scrubbed coal fired power plant.

Another possible sulfur compound is H2S. (Rotten egg gas.) You aren't likely to have it in the air either, but if you did, it would cause trouble with tools. Iron and copper sulfides (which would eventually result from the H2S and either copper based metal or steel based metals) is jet black. I have had more experience with H2S than SO2, and you shouldn't have much of it either, but if you did, the corrosion on the tools would be black. (Again, you aren't likely to have it because it is on the order of the same toxicity as is the hydrogen cyanide that they used to use to execute prisoners. Also, you can smell it at very low PPM levels, although it becomes undetectable quickly if you are around it, because it deadens your ability to smell it.)

Stew

[Jim Falsetti]

Are you referring to the ~1080 MW Tolk plant, which seems to be the only coal plant relatively near Lubbock? Where are you located relative to the plant and are the prevailing winds blowing towards your shop?

Stew, there are coal plants operating in the US without SO2 scrubbers.

Tolk burns subbituminous coal. I didn't scan the EIA database to see the SO2 emissions from Tolk, but subbituminous is a lower sulfur coal, typically on the order of 0.3%. It is likely the Tolk plant doesn't have SO2 scrubbers, but relatively unlikely its SO2 emissions are affecting your bronze plane, unless you are very close to the plant, as in working in the plant.

Best - Jim

[Tony Wilkins]

Are you referring to the ~1080 MW Tolk plant, which seems to be the only coal plant relatively near Lubbock? Where are you located relative to the plant and are the prevailing winds blowing towards your shop?

Stew, there are coal plants operating in the US without SO2 scrubbers.

Tolk burns subbituminous coal. I didn't scan the EIA database to see the SO2 emissions from Tolk, but subbituminous is a lower sulfur coal, typically on the order of 0.3%. It is likely the Tolk plant doesn't have SO2 scrubbers, but relatively unlikely its SO2 emissions are affecting your bronze plane, unless you are very close to the plant, as in working in the plant.

Best - Jim

Yes, tolk. I know nothing about coal power plants but was suggested it might be a problem elsewhere. It seems as though it won't be a problem. Prevailing winds? The plant is northwest of us and we get winds from that direction generally a lot of the time.

[Patrick Chase]

To start with, I can't imagine a coal fired plant that does not have an SO2 scrubber. In this day and age, and especially in a state like Texas, this does not happen. Such a plant would have been shut down YEARS, EVEN DECADES ago by the government.

SO2 emissions have been reduced by about 2/3 from their 1970s peak (anybody else remember "acid rain"?), but it was done via a cap-and-trade program with an overall (not per-state/locality/utility/plant/etc) limit, rather than by strict per-source regulations. As others have pointed out, this means that an individual plant need not have scrubbers so long as its operator buys credits from others that do. The outgoing administration has attempted to impose per-plant regulations as well, but who knows what will happen with that.

Also I would think that a "state like Texas" is exactly where such stuff would be most likely to happen :-).



If you had continuous emissions of high levels of SO2, and you would if you had a coal fired plant with no scrubbers, you would find that everything near, made of mild steel, would undergo significant corrosion.

Depends on weather and stack height. Even back in the 70s the plants that were the ultimate sources of acid rain used very high stacks to loft the oxides (Sulfur and Nitrous) high enough into the atmosphere that they didn't come down anywhere nearby. I don't know about the specific plant near the OP's home, but I don't think you can generalize to "everything near" without a lot more information than we have in this thread.



If you did have an SO2 problem, it would be extremely obvious, and people would be screaming for the state government to do something.

Yes, but the audibility of such screaming is oddly but strongly tied to the socioeconomic status of the people doing it. People in less well-to-do neighborhoods experience symptoms as you described in the part of your post that I snipped all the time, and are generally ignored until/unless it reaches crisis proportions. Just ask the residents of Flint, MI.

[Stanley Covington]

Airborne SO2 is seen in Japan around hot springs with a high sulfer content venting into the air. Naruko is famous for this. But you can tell when it is around because it affects EVERYTHING. Cars rust badly. Rebar swells and bursts. Pipes crumble. Brass plumbing fittings lose their plating and go away within a few years. Aluminum sash (doors/windows) turns white and develops deep pitting. Everything metal must be replaced in a few years.

My point is that if there is enough airborn ambient SO2 in your area to hurt your plane, it would be very obvious. Is that the case?

[Tony Wilkins]

Airborne SO2 is seen in Japan around hot springs with a high sulfer content venting into the air. Naruko is famous for this. But you can tell when it is around because it affects EVERYTHING. Cars rust badly. Rebar swells and bursts. Pipes crumble. Brass plumbing fittings lose their plating and go away within a few years. Aluminum sash (doors/windows) turns white and develops deep pitting. Everything metal must be replaced in a few years.

My point is that if there is enough airborn ambient SO2 in your area to hurt your plane, it would be very obvious. Is that the case?

No, not that I noticed.

[Stanley Covington]

No, not that I noticed.

Someone familiar with Texas may know, but many populated states have government agencies responsible for monitoring air quality. IIRC, in California, it is the Air Resources Board of the Cal EPA. Questions of competency and wastefulness aside, the ARB will respond to citizen requests for testing reports of air quality. Will TCEQ have similar information?

[Ray Selinger]

Acid fumes do a number on tools, even after cleaning they seem to rust much more easily.

[Jim Falsetti]

Stanley, yes, the Texas authorities do publish Tolk power plant emissions, and so does US EIA, and most probably EPA. It's all out there if anyone cares to look.

But we are drifting way off topic now...

Best,
Jim

[Pat Barry]

Seems to me people should be a bit more worried about their health than their tools getting a tad rusty!

[Stanley Covington]

Stanley, yes, the Texas authorities do publish Tolk power plant emissions, and so does US EIA, and most probably EPA. It's all out there if anyone cares to look.

But we are drifting way off topic now...

Best,
Jim

Not off topic at all. Tony can check with the Texas Agencies to see if there is data specific to his area, and use that that to confirm whether airborne SO2 is higher than normal in his area or not. This may help him decide how to prevent corrosion to his tools.

The ideal solution would be to actully measure SO2 around his house, but that would probably be difficult/expensive unless he could convince gubmint agency or school with the sampling bottles and testing equipment to do it for free. It ain't rocket surgery.

Perhaps some of the chemists, engineers and scientists on the forum could suggest a quick and dirty method. Homemade litmus paper maybe? ;)

[Stew Denton]

Hi Patrick,

This is way off track, but......

I hate to admit it, but I have to eat a little crow, and agree with a lot of what you are saying, but not all of it. I know quite a bit about the technology, but what I thought about the environmental rules was wrong. I need to stick with the technical questions.

I visited a little with one of our retired environmental guys, an extremely knowledgeable guy, and he confirmed some of what you have written above, but did not agree with all you wrote.

He said the plant in Lubbock was operating without scrubbers, as you mentioned, buy using coal with sulfur content below 0.3%, but the Obama administrations environmental folks had been trying to force them to add scrubbers anyway. They were going back and forth on this at the time. He didn't know what had become of that situation.

He thought the sulfur cap and trade did work fairly well, as you stated, but said it is a pretty expensive way for a plant to operate.

One point where he did not agree is that the high stacks stopped all the local problems. Before coming to the Texas panhandle, he came from Ohio, and in their region near the plant where he worked, SO2 emissions could be a serious problem at times, even with the high stacks, given certain weather related situations. He saw it take paint of exterior steel surfaces over a period of time, etc., if I understood correctly what he was telling me. This is not with the really low sulfur coal like they are burning down in Lubbock, however, it is coal with a lot more sulfur. By his words, "it was bad." One plant did not have scrubbers. He didn't talk about governmental repercussions, though.

He absolutely did not agree with you about the socioeconomic conditions being a big factor, it certainly was not in the general area where he lived. All kinds of people would scream if there was a problem, and politicians would listen.


Years (quite a few) ago, when I was running the certified environmental lab at the plant where I worked, I was involved with an industrial group that worked together in coordination with the state regulators (but this was not in the State of Texas), and knew folks that ran some large commercial environmental labs. They ran environmental samples from all over the US, and had to be certified in every state that they ran samples from, for reporting purposes. At that time they told me that Texas was one of the 5 most stringent states environmentally in the US, that is what I meant by "a State like Texas." (California was worse.)

Finally, for what it's worth, if there was a tiny fraction of enough SO2 in the air to attack steel or bronze, a woodworker would not be able to stand working in that area, the SO2 would drive him out of the shop. So what ever the problem is, it is not caused by un-scrubbed coal fired stack gas SO2. That was the point I was trying to make.

I appreciated your comments, and again stand corrected.

Stew

[Stewie Simpson]

An in-depth discussion on S02 emissions on a Neanderthal Hand Tool Forum. The mods must be in holiday mode.

[Stanley Covington]

Thanks, Stew, for the time and effort. Very interesting.

Stan

[Frederick Skelly]

+1. Thanks Stew.

[Tony Wilkins]

Thanks, Stew, for the time and effort. Very interesting.

Stan

Yes, thanks! I've gone from wondering if this might be an issue from a position of total ignorance to thinking it probably is not anything to really hoping it ain't so lol. Still at a point it seems unlikely however.

thanks for everyone who provided their insight and knowledge.

[Tony Wilkins]

An in-depth discussion on S02 emissions on a Neanderthal Hand Tool Forum. The mods must be in holiday mode.

I'm sorry but I'm not quite sure what you mean by that.

[Dave Anderson NH]

We Mods don't generally interfere when a thread drifts partially off topic unless things delve into those areas that violate the TOS (terms of service). The drifts in this particular cased were directly related to the question from the original poster and therefore relevant.

[Jim Falsetti]

Stewie, this has not been an in-depth discussion on SO2 emissions, we are merely scratching the surface. If you would like, we can have a rich and full dialogue on the many aspects of SO2 emissions... starting with the sulfur content in various types of coal, use of high sulur petroleum coke, stack gas scrubbing technologies, pre or post-combustion sulfur mitigation, direct-fired combustion vs. partial oxidation, acid gas removal technologies, sampling techniques...and way more!

After exhausting this topic, we can move on to other coal plant emissions like mercury, coal slag, the fate of vanadium, etc.... but it's way more fun to talk about woodworking instead.

Best,
Jim

[daniel lane]

Another possible sulfur compound is H2S. (Rotten egg gas.) You aren't likely to have it in the air either, but if you did, it would cause trouble with tools. Iron and copper sulfides (which would eventually result from the H2S and either copper based metal or steel based metals) is jet black. I have had more experience with H2S than SO2, and you shouldn't have much of it either, but if you did, the corrosion on the tools would be black. (Again, you aren't likely to have it because it is on the order of the same toxicity as is the hydrogen cyanide that they used to use to execute prisoners. Also, you can smell it at very low PPM levels, although it becomes undetectable quickly if you are around it, because it deadens your ability to smell it.)

Stew's got a good point (I've read through the whole thread, so caveats included), but I couldn't help but point out that H2S is an *extremely* common offgas near kraft pulp mills, so there would be plenty of info on this being an issue. Kraft mills use a sulfate-based process and regularly produce H2S, which last I saw was regulated by the government to somewhere around 5ppm in the stack; however, the odor threshold for humans is 3 orders of magnitude lower (~5ppb), so it's easily detected even diluted in air from within regulated concentrations. If you had H2S around to impact your tools, you'd know it from the smell!


d

[Tony Wilkins]

H2S was mentioned also and it might be the result of a water heater. The water heater is across the garage in a closet.

[Malcolm McLeod]

... kraft pulp mills, ...

There was a tree in Lubbock once, but the dogs all fought over it, so they removed it. ...I'm guessing source of the problem is not a pulp mill.;) Nearest tree to Lubbock is ~500 miles, but on a clear day you can see it. (I lived in Amarillo. Twice. And they have same problem there.)

There are many sour gas wells in the Permian, but I doubt this is the source of the problem either, as the air quality is closely monitored for life safety reasons. H2S is deadly.

[Tony Wilkins]

LOL. So true.


There was a tree in Lubbock once, but the dogs all fought over it, so they removed it. ...I'm guessing source of the problem is not a pulp mill.;) Nearest tree to Lubbock is ~500 miles, but on a clear day you can see it. (I lived in Amarillo. Twice. And they have same problem there.)

There are many sour gas wells in the Permian, but I doubt this is the source of the problem either, as the air quality is closely monitored for life safety reasons. H2S is deadly.

[Patrick Chase]

I hate to admit it, but I have to eat a little crow, and agree with a lot of what you are saying, but not all of it. I know quite a bit about the technology, but what I thought about the environmental rules was wrong. I need to stick with the technical questions.

Thank *you* for digging deeply into this and clearing up the stuff where I was fuzzy (stack height impacts etc). I've agreed all along that the probability of SO2 being the culprit here was low all along btw. I should have spelled that out instead of just nit-picking :-).

IIRC Texas has made their regulations more business friendly over the past couple decades, so a lot depends on when you had the discussion you describe.

[Barney Markunas]

I guess most anything is possible, but I think that old medical expression "when you hear hoofbeats, think of horses not zebras" is probably on target here. Regardless I would think that a little polish like Simichrome or Flitz followed by some wax should keep your plane in reasonable shape. Frequent use should really minimize the amount of tarnish you get on the sole.

[Jerry Bruette]

I used to work in a pulp mill that used SO2 in it's acid for cooking the wood chips. I think if you had a SO2 or H2S problem in your house or shop that was affecting your tools you could smell either one.

Is it possible that you're storing some household or gun cleaning products near where your tools are being kept? Some household cleaners contain acid of one type or another and many gun cleaning solutions contain ammonia. Both of which could have corrosive affects on your tools.

SO2 is also used as a preservative in some food, check a package of dried pineapple, and at one time many years ago it was used as a refrigerant in early refrigerators until a safer better smelling chemical was developed.

[Ron Bontz]

Well, this was way over my head but interesting. I remember the days of acid rain. Thanks for posting.

[James Pallas]

If you have rust problems in general and you have a gas water heater in the shop that may be the problem. They produce a large amount of water vapor. If the water heater is not venting properly that water vapor will do it. It will also produce fumes if not venting correctly. Seems like it must be something in your shop and not from outside.
Jim

[Patrick Chase]

SO2 is also used as a preservative in some food, check a package of dried pineapple, and at one time many years ago it was used as a refrigerant in early refrigerators until a safer better smelling chemical was developed.

Of course that safer better-smelling chemical (Freon) turned out to have eaten a hole in the Ozone layer, and was banned. We're on plan C now (or D if you also count the interim use of HCFCs between Freon and the current HFCs)

[Dave Beauchesne]

I have been a HVAC guy for 38 years now ( EEEEK!! )

I have been at a Pulp / Paper Mill for the past 15 - there are trace amounts of H2S and SO2 most everywhere and some buildings a bit more than others, even when there are no excursions / leaks.

What I see is as follows: Copper and brass turn black in some of the worst buildings, sometimes within weeks. Most of the Mill site - copper and brass oxidize - to varying degrees of black - at higher rates than ' outside ' the Mill site. I see little to no green oxidation, just blackening of the copper or brass ( and HVAC equipment has a fair amount of both.

Dissimilar metal contact points take a kicking in the atmosphere as well.

One of the worst places for attack ( a bit off topic but interesting none the less ) is the braze compound universally used in HVAC systems that is a copper ( 80 + % ) silver ( 15% ) and a bit of phosphorous ( as a fluxing agent ) - one trade name is Silfos. It is used because it is self fluxing on copper, melts in the 1300 F range and has great gap filling capabilities - very easy to use, and will take 600 PSI +++ no problem.

The one issue at Pulp Mills ( and at rubber tire manufacturing plants so I am told ) is that the trace amounts of sulfur in the atmosphere attack the phosphorous and essentially turn it into Swiss Cheese and leaks occur - sometimes quite bad quite quickly, sometimes enough to weep the lubricant that is continually circulating in the system, but not leak any refrigerant.

Silver solder ( actually a brazing range product ) that has 45% silver and melts closer to 1200 F has no leakage problems from the sulfur floating around ( due to no phosphorous ) but is not used as much as joint cleanliness and an added fluxing agent are required.

Soft silver bearing solder ( in the 500 F range ) works well as well, but the high pressures of the newer refrigerants are a strain and joint failure is common.

Sorry to cause a snooze fest, but I have a couple LN block planes in yellow and white bronze at home that are great and cause me no grief.

Good luck.

Dave B