Talk:Soot

Carbon black

"this use accounts for around 85% of the carbon black market" o_O what? Carbon black market? As in [Carbon black] [market], or [Carbon] [black market]? Slightly confusing.

Not really, its clearly "[Carbon black] [market]" from the context, i.e an article about 'carbon black'. StealthFox 05:01, 9 December 2005 (UTC)

It might be useful to include an explanation that carbon black is an essential component in the manufacture of tires of various kinds, as it improves the traction and wear characteristics of both natural and synthetic rubbers. Perhaps, just a mention, with a referral to tire manufacturing. —Preceding unsigned comment added by Homebuilding (talk • contribs) 01:29, 7 September 2010 (UTC)

Need to incorporate discussions of furnace black and thermal blacks, the most commercially viable forms of carbon black, much, much larger volume markets than lampblack. — Preceding unsigned comment added by 67.10.239.23 (talk • contribs) 09:58, 19 December 2005 (UTC)

The confusing text has since been removed from the article, and we now have a separate article, Carbon black. -- Beland (talk) 19:00, 23 September 2024 (UTC)

Reflectivity

"Lampblack produced in this way is both the darkest and least reflective substances known."

Can that statement really be true?

Over the visible light portion of the spectrum, maybe. Check this out: http://www.tinmantech.com/assets/images/anneal6.JPG Now that's low reflectivity if'n I never seen it!

Lamp Black in Candy

Lamp black is NOT used as a coloring agent in candy. Lamp black is made from incompletely burned petroleum, and is considered to be carcinogenic. Licorice candy is colored with molasses, carmel, and a mixture of food colorings.Iepeulas 02:27, 12 June 2006 (UTC)

Agreed, removed...

I'm still confused as to whether soot is the stuff in the bottom of your fire when it's gone out.

It is not. That's ash, and consists primarily of unburned material. Soot consists of burned and re-formed fuel. Maury 22:00, 1 June 2007 (UTC)

Firelight is not blackbody radiation

Blackbody radiation is an idealization of a uniform substance with unit emissivity in thermal equilibrium. The conditions existing within a flame are far removed from those of thermal equilibrium. In particular, there is an intense intrinsic source of thermal energy in the form of the chemical reactions producing the flame. It is, therefore, incorrect to characterize the thermal radiation produced by soot in a flame as "blackbody radiation". Hetware 03:19, 21 August 2007 (UTC)

Photo of the truck is a fake

Unless the semi truck in the photo just thew a connecting rod at the point the photo was taken, the smoke plumes in the photo are fake. Even if a diesel engine smokes bad, it is never that bad. If a truck has bad engine that smokes, the truck and its trailer quickly get coated in a layer of grime. The tanker trailer in the photo is clean and shows no signs of soot. It appears the folks at the EPA are employing trickery to make a political point. 98.108.76.78 (talk) 12:41, 7 April 2009 (UTC)

Plumes even larger than those shown are commonly seen when a "large diesel truck, without particle filters" accelerates under load, especially when double-clutching, right after a gear change, or when the engine has not yet warmed up. See http://en.wikipedia.org/wiki/Diesel_exhaust#Variation_with_engine_conditions Ocdnctx (talk) 18:56, 8 January 2012 (UTC)

Not on any modern truck (electronic fuel injection), no. This image was a propaganda image from the EPA, and the truck pictured dates from the 1970s and is notably NOT under load. The image is also pretty much irrelevant to the article subject -- a more appropriate image would be depicting an image of soot by itself, not diesel exhaust. Stian (talk) 15:26, 29 April 2012 (UTC)

It's certainly possible to make engines do this; sometimes people do this intentionally, which can involve removing exhaust filters (see Rolling coal). I've certainly observed that myself in person on the road. The image seems quite relevant, as vehicle emissions have historically been (and in some countries still are) a major source of soot. The caption clarifies that the truck is not using particle filters. There's no particular reason to think this image has been digitally faked - the trailer may appear clean because it's just been washed in preparation for being in a photo shoot, or it's not depicted clearly, or this engine only does this when it's starting up, or any number of other explanations. -- Beland (talk) 18:56, 23 September 2024 (UTC)

Merge with Black carbon

These pages seem to refer to the same substance, and perhaps they should be merged.

--Ilnyckyj (talk) 21:32, 3 December 2009 (UTC)

Role in Global Warming

These sentences contradict one another "The absorbed fraction of solar radiation results in surface cooling because the solar radiation that would have reached the Earth is absorbed in the atmosphere. Although surface warming is seen under these conditions, atmospheric warming is also observed because the incoming radiation is trapped in the atmosphere.[10]" I believe that the second sentence is correct because conversion of solar radiation to heat in the troposphere by soot would be expected to increase surface warming. What exactly does the author mean by surface temperature; the temperature of the ground or the temperature of the air at ground-level. —Preceding unsigned comment added by Hammond Forest (talk • contribs) 17:15, 23 December 2009 (UTC)

I agree that they contradict, just wanted to log my opinion as well. I recommend removing the argument or going through the paper to see what the author really meant. 128.156.10.80 (talk) 14:52, 13 September 2010 (UTC)9/13/10 Mike134

Diesel Soot

Also, see: http://en.wikipedia.org/wiki/Diesel_soot #REDIRECT [[1]]. I was dismayed that diesel wasn't included. By now most of us know that unfiltered diesel engines spew particulates. Are railroad train engines that fill the neighborhoods with the characteristic diesel odor filtered ... I think not. So far, The Diesel Emissions Reduction Act is active only in CA and has little focus on Railroad Lines. See: http://www.epa.gov/cleandiesel/documents/fy12-dera-infosession-presentation.pdf.— Preceding signed comment added by PointyHairedEE (talk • contribs) 16:15, 15 June 2012 (UTC) PointyHairedEE (talk) 18:11, 15 June 2012 (UTC)

The United States' DERA (Diesel Emmisions Reduction Act) program provides funds for clean diesel conversion

The United States' DERA (Diesel Emmisions Reduction Act) program provides funds for clean diesel conversion — Preceding unsigned comment added by Ocdnctx (talk • contribs) 15:14, 16 June 2012 (UTC)

Soot, Black Carbon, Carbon black

Please see my suggestions at Talk:Carbon_black#Soot.2C_Black_Carbon.2C_Carbon_black. --NHSavage (talk) 13:16, 7 October 2012 (UTC)

I’m still somewhat confused after reading that discussion ... --Dustfreeworld (talk) 11:22, 5 February 2024 (UTC)

Merge proposal

I propose to merge black carbon into soot, because it seems that soot is the common name for black carbon. See for example:

“commonly called soot, but also known as black carbon” https://svs.gsfc.nasa.gov/3665/

“Soot particles, also known as black carbon (BC) aerosol” https://acp.copernicus.org/articles/23/15039/2023/

“Black carbon, commonly known as soot” https://www.cleanairfund.org/news-item/the-world-thin-ice-black-carbon/

“Black carbon (BC) – also referred to as soot” https://drawdown.org/publications/reducing-black-carbon/a-triple-threat

Black carbon, also known as "soot," https://www.epa.gov/international-cooperation/black-carbon-diesel-initiative-russian-arctic Chidgk1 (talk) 08:13, 22 September 2024 (UTC)

Hmm, the intro to black carbon defines it as small particles of pure carbon which are one component of soot, and soot defines that as small particles made of carbon plus impurities. It's possible some sources consider them synonyms because they are "close enough" but other sources may go into details which are applicable to one but not the other (e.g. exact physical properties and medical effects). Would this be confusing if put into a single article, or do the details generally apply to both or get mixed up in the existing articles? -- Beland (talk) 08:28, 22 September 2024 (UTC)

@Beland Sorry I am not an expert and I cannot find in the cite where it says that there other components of soot besides black carbon. In any case the cites I quoted above are maybe more authoratative than that single 2012 study. So what do you think - do you support or oppose this proposal? Chidgk1 (talk) 16:38, 22 September 2024 (UTC)

@Beland Oh I see the supposed difference was explained clearly on “https://nomoreplanet.com/” which seems no longer to exist. But I think NASA etc above are more authoritatative. Chidgk1 (talk) 16:47, 22 September 2024 (UTC)

@Beland This 2023 paper seems to treat them as the same. Chidgk1 (talk) 16:52, 22 September 2024 (UTC)

Sipkens et al. say "The term soot has meant different things over time and in different research and engineering communities" and have links to articles discussing different definitions, including Michelsen et al. This article from Petzold et al. goes through various historical definitions of "soot" and "black carbon" and related terms, which it points out are sometimes used as synonyms even when different measurements are attached to different words. They make recommendations as to how the terminology and measurements can be standardized.

I think merging would probably be helpful, and would work best if 1.) we add a section on terminology that explains the conflicting definitions and attempts at standardization and 2.) for each mention of "soot" or "black carbon" in the article, we specify which definition the cited source is using (or say the definition is unspecified, as a warning it might not be comparable with similar claims). Explaining the terminology also offers an opportunity to carefully explain the various constituents of soot, which would also be very informative for readers (which the article sort-of does now, but it could be improved). -- Beland (talk) 18:47, 23 September 2024 (UTC)