Talk:Blast furnace

From Wikipedia, the free encyclopedia

 This article is part of the History of Science WikiProject, an attempt to improve and organize the history of science content on Wikipedia. If you would like to participate, you can edit the article attached to this page, or visit the project page, where you can join the project and/or contribute to the discussion. You can also help with the History of Science Collaboration of the Month.

Sheffield says:

This process was made obsolete in 1856 by Henry Bessemer's invention of the blast furnace ....

which appears to contradict this article. Or is it that the 1865 invention is the steel blast furnace, as opposed to the iron blast furnace? -- Tarquin 10:10, 25 Aug 2003 (UTC)

The two processes are basically unrelated, although admittedly very similar. The blast furnace creates pig iron by mixing iron oxide with coke and burning it, resulting in slag and high-carbon iron. The iron is not useful on it's own. The bessemer process then takes this iron and blasts it again, without coke, to burn off the carbon and produce steel. The advantage is that the bessemer reactors can be fed with the hot pig iron from the blast furnace, thereby dramatically reducing the total amount of fuel needed to keep the process running. Most steelmills consisted of an assembly line starting with a blast furnace, then feeding a number of convertors.

Contents

[edit] Low and high blast furnaces ?

Hello,

in French, we make the difference between

  • the "low" blast furnace (bas-fourneau): used until the end of the Middle-Age, they can only produce solid stuf (high-carbon content) ,the temperature is too low to melt; the stuff is then processed (heated and beaten) to remove the carbon; they have the size of a human;
  • the "high" blast furnace (haut-fourneau): 7-10 m high, the metal melts and they produce cast iron (fonte).

Is there in English a specific vocabulary to separate the high and low blast furnaces ?

Cdang 15:28, 25 Oct 2004 (UTC)

What you're describing as a bas-fourneau, where liquid slag is beaten out of a solid mass of hot iron, is called a bloomery in English (because the spongy masses of iron produced by this method are called blooms). I have never heard "blast furnace" used to describe anything but an iron smelter hot enough to produce molten iron. Shimmin 18:34, Oct 25, 2004 (UTC)

Thanks. Well, all that's left is to create the Bloomery article... However, in the history part, is the blast furnazce so old (5-1st century BC)? I thought at that time there was only bloomery. Cdang 12:32, 28 Oct 2004 (UTC)
Yes, the blast furnace is that old ... in China. Chinese furnace technology, originally developed for large-scale pottery works, reached the melting point of iron perhaps as early as 1000 BC, although it was not immediately applied to iron-working. In the west, no one built furnaces that hot until the 1200s. The Han dynasty established iron production as a state monopoly and built several large blast furnaces. You can read an article about one of the better-preserved archaeological sites here.[1] Shimmin 13:26, Oct 28, 2004 (UTC)
That is because the Chinese iron ore contained an awfui lot of phosphorous. It did melt in temperatures below 1000 deg C, easily attainab.e with technology of the era. The European iron ores are usually low of phosphorous and the iron melts only on higher temperatures. The first European blast furnaces ar found in Sweden in the 12th century. It is possible cast iron was produced already earlier by Catalan forge.
Great! A good lesson of humility (-: Cdang 09:15, 8 Nov 2004 (UTC)

[edit] blast furnace

I have edited this page slightly, as the account had so excessively simplified as to be incorrect. I am less familiar with the processes of the late 19th century and beyond, and hope that I ahve not succeeded in introducing errors.

As far as is known thus far, the Chinese and European processes were developed independently.

The whole subject is in fact rather more complicated than indicated, with a variety of processes in use at different periods.

There is no direct English equivalent of the French bas-fourneau; the equivalent term is bloomery, though the vernacular term may have been bloomsmithy or merely smithy, but the latter word is now used for a blacksmith's shop.

(I think I made the above comment some time ago) Peterkingiron

Visitor

the formula given in the process section is unbalenced it has 9 oxgen going in and only 6 oxgen after the reaction could someone corect this?

The statements about the use of the blast furnace in ancient Europe are almost certainly incorrect. Peterkingiron 22:45, 7 April 2006 (UTC)

I have filled out some further details of the history of the process, where the text lacked balance. I hope that in doing so, I have not introduced further errors or vandalised others work. If the statements about the blast furnace in Roman and pre-Roman Europe are correct, a reference should be provided, as this seems controversial (top say the least). Peterkingiron 23:47, 7 April 2006 (UTC)


[edit] Rievaulx

I thought that the section about Rievaulx was overstated and have toned this down. I hope that in doing so, I have not vandalised good work. If I have and the author wishes to restore it, he should cite his authority, as this remains a controversial issue. Peterkingiron 00:09, 8 April 2006 (UTC)

The reuirement of material to appear in Wikipeadia is that it should have been neutral. The site on the Rievaulx estate is the only medieval blast furnace known in England. It is NOT only one in Europe and was thus not necessarily the most advanced. Some of Gerry MacDonald's work has been the subject of brief publication. However there is no evidence that I have heard of that blast furnace technology was transferred from China by the Mongols (or any one else), but neither is thee evidence to the contrary. This is a controversial issue and should not be dealt with here. Nor is there published information (that I have seen) as to how long the furnace operated. Information from Gerry MacDonald (depsite his eminence) is not an adequate peer-reviewed source.

It would also be helpful if the person who has been altering this section would ahve the courtesy to sign in so that his work bears his signature. Peterkingiron 20:54, 10 April 2006 (UTC)

The normal historical description for the end of English monastries is 'dissolution', not closure, which is why I made that change. Ironmaking continued in the Rievaulx area immediately after the Dissolution, and it is thus improbable that tecnological knowledge was lost. In any event, a blast furnace was built at Rievaulx not long after. If the older technology there really was so advanced, why? In any event the Industrial Rrevolution for the iron industry did not consist in the adoption of a blast furnace process, but in the substitution of coal for charcaol in the whole process. Peterkingiron 21:02, 10 April 2006 (UTC)

It was not the only one in Europe, but it is the most advanced blast furnace known/ The Cistercians were skilled metallurgists, and almost all of the iron was extracted from the ore at Laskill. By extracting such quantities of iron, it could have ushered in an Industrial Revolution, according to Gerry MacDonald and a number of other historians. The dissolution of the monasteries broke up the potential for the technology to be spread across Europe, while the blast furnace itself was no longer used. The sources are already on the Rievaulx Abbey article, so I'll also add them here:
Grimhelm 19:58, 11 April 2006 (UTC)
Thank you for quoting your sources. The Telegraph article is a report of an interview with Gerry MacDonnald, who reported and investigated the site. So far the only academic report that I have seen on this subject is a technical one on the methods used to investigate the site, and a brief interim report on the intitial excavation. I have been awaiting seeing a detailed report with considerable interest. The General Chapter of the Cistercians has been argued to have been an important mechanism for conveying ideas, including technology. I have not seen Thoams Woods' book, but would be surprised if he had a better source. His writing appears to be quite wide-ranging, and I would thus be surprised if he were a particular expert on this subject; I may of course be wrong. Nevertheless, your case is still overstated. It is possible that Laskill was the most advanced ironworks in England, but it is unlikely to predate (or be more advanced than) Lapphytttan or furnaces in south Germany and in Mark (North Rhine-Westphalia), which date to the 13th or 14th century. There is also the little question of dating: I am not clear what date Gerry MacDonald is claiming for Laskill. Is it 14th cnetury or 16th century? Did it make pig iron throughout or merely for a short time? I expect that you do not have the answers to this. We both need to await the proper publication of the subject. For the moment, this is rather too close to being original research that has not yet been peer-reviewed to appear here.
Similarly, the links with China (via the Mongols or any other route) may (or may not) be right. The linkage (as far as I know) depends on no more than mere speculation. Peterkingiron 22:17, 12 April 2006 (UTC)
I had also been guilty of not citing sources. I have now partly remedied that. As indicated above, just how significant Laskill was is not yet clear. I have once again toned down your statements a little. Laskill is probably only of national importance in England, rather than of European importance.
I remember seeing an academic article on technology transfer and the Cistercian General Chapter, but have been unable to find it again. This could usefully be added.
I have sought to alter what you have written as little as possible. However I have removed the statement about the industrial revolution again. The industrial revolution article is a good one, and I would ask you to read it carefully. For the iron industry, it consists in a very great expansion in production, starting in about 1785. That depended on the use of coal (instead of charcoal) for the whole ironmaking process. Whatever Gerry MacDonald had in mind when the Daily Telegraph interviewed him, I do not think he can have meant that. If you want more detail on this issue, please see my article in Economic History Review LVIII(1) (Feb. 2005) or my doctoral thesis.
There remain further unreferenced sections. I will try to deal with those that I have written in coming days.

Peterkingiron 23:15, 12 April 2006 (UTC)

I have added a further reference for Laskill, but regretably there does not seem to be a proper published report on the site giving a date for it. Peterkingiron 15:45, 14 April 2006 (UTC)
I think Thomas Woods had another source, dating it to have commenced cast iron production a few years before the dissolution of the monasteries - I'll have to check this. However, the article has certainly been improved since I last looked at it, and I'll try to bring the Laskill section up to standard. Grimhelm 15:28, 21 April 2006 (UTC)
If Thomas Woods had another source, I would be pleased to know what it is. The source that I added gives bo date. I was in touch with the author, who referred me to a rather fuller article on the archaeological technique, but I suspect that research is on-going, and we will have to wait some time before the site is fully published. Peterkingiron 22:34, 21 April 2006 (UTC)

[edit] Ancient Europe

I have hitherto refrained from amending the 'Ancient Europe' section, though I am fairly sure that it is wrong. There is no source for this section, so far as I can see. The nearest thing is an extract from a 1963 book, which is likely to be quoting from even older work, and is almost out of line with existing views. I suspect that the author has assumed that a bloomery ws a blast furnace, because a blast was applied to it; however that is not a normal use of the term.

Unless some one can provide a satisfactory source, I propose to alter this section by briefly describing bloomeries (on which there is a separate article) and changing the early references to blast furnaces (except as to China) to bloomeries. If there is some one out there who has a reliable authority for the present text, please cite it. Peterkingiron 13:00, 28 April 2006 (UTC)

It is almost certainly wrong. Cast iron was produced by other furnaces, but not in the quantities produced by blast furnaces, though early blast furnaces were often clumsily inefficient. This should certainly be corrected.Grimhelm 16:35, 28 April 2006 (UTC)
I have assumed that whoever wrote about ancient Europe had a reputable source, but either he or his source misinterpreted term 'blast furnace' to mean any furnace that was artifically blown. I have altered this, and added an explanation of the difference between the bloommery and the blast furnace. As I understand it, there is little or no evidence for cast iron in ancient Europe, but I am not an expert on that. Peterkingiron 16:42, 30 April 2006 (UTC)
Retrieved from "http://en.wikipedia.org../../../b/l/a/Talk%7EBlast_furnace_ba67.html"