Talk:Blast furnace/Archive 1

Obsolete?

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)

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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.

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)

A small correction!

The difference between Bloomery and Blast furnance is as stated that bloomerys do not melt the iron. The case for that is the LOW carbon content that makes the melting point of the iron higher than the melting point of iron oxide. Redsult: You get a bloom of iron with some slag included, slag that have to be beaten out of the bloom, but is usable as it is, not brittle. In a blast furnance the high carbon content lovers the nmelting point so that the iron can melt without collapsing the content to a solid mass that will stop the gasflow since as is usual with metal oxides the oxide will not melt while the high carbon melts melts. The melting helps in separating slag from metal. The cast iron pig is then remelted and worked so that the carbon can be oxidazed out - or in later practice blown with air while still melted. (In Bessemer process and Caldo-process as examples.)

A common mishap in bommery is that the oven runs too high and the mass collapses and bloks gasflow.

A common mishap in blast furnance is that either: the iron is not enough carbonized and either do not melt or melts after the oxides have melted: mass collases and blocks airflow.

Or: airflow oxidizes out carbon in the melted iron which solidifies. If too much solidifies you get a bloom that blocks the furnance. Seniorsag 14:45, 20 June 2007 (UTC)

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

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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?

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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)

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:

• How the Catholic Church Built Western Civilization, Thomas Woods, (2005), ISBN 0895260387
• Henry "Stamped Out Industrial Revolution", David Derbyshire, The Daily Telegraph (21 June 2002)

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)

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)

Good Article Nomination

Overall, very good. However, that said, it could be improved. The only problems I have with this article becoming a good article are:

1. The style of writing in the 'Process' section.
2. More information about blast furnaces today is needed.

GA review (see here for criteria)

1. It is reasonably well written.

   a (prose): b (MoS):

2. It is factually accurate and verifiable.

   a (references): b (citations to reliable sources): c (OR):

3. It is broad in its coverage.

   a (major aspects): b (focused):

4. It follows the neutral point of view policy.

   a (fair representation): b (all significant views):

5. It is stable.

   

6. It contains images, where possible, to illustrate the topic.

   a (tagged and captioned): b lack of images (does not in itself exclude GA): c (non-free images have fair use rationales):

7. Overall:

   a Pass/Fail:

I strongly recommend you make the above changes to this article as otherwise the article is very concise, and would probably pass as GA. Smomo 19:12, 28 February 2007 (UTC)

I took a crack at cleaning up the process section. I agonized about deleting so much about iron refining, but ultimately it had to go because it's really nothing to do with blast furnaces. I'm not opposed to putting all that stuff back, but it needs a better place within the article. I'm sure that was written by Peterkingiron. He contributes good stuff, but most of that information was duplicated in the articles that it linked to (also the product of Peterkingiron). Let's discuss. BSMet94 21:05, 28 February 2007 (UTC)

Yes, that's better and much more relevant. However, I am still concerned that this article doesn't really deal enough with the modern blast furnace. It goes into a good amount of depth for history and chemistry, but I just feel like there could be extra information about the blast furnace today. It just feels like the article needs a bit more content, just a bit, about the blast furnace. That said, that is just my opinion, and anyone else is of course welcome to comment. Smomo 18:10, 1 March 2007 (UTC)

How is it now? I have expanded on modern blast furnaces and the supporting facilities, buildings and processes, etc. [2] --Grimhelm 22:32, 2 March 2007 (UTC)

Ah yes, that's much better. Here's my GA review of this article...

GA review (see here for criteria)

1. It is reasonably well written.

   a (prose): b (MoS):

2. It is factually accurate and verifiable.

   a (references): b (citations to reliable sources): c (OR):

3. It is broad in its coverage.

   a (major aspects): b (focused):

4. It follows the neutral point of view policy.

   a (fair representation): b (all significant views):

5. It is stable.

   

6. It contains images, where possible, to illustrate the topic.

   a (tagged and captioned): b lack of images (does not in itself exclude GA): c (non-free images have fair use rationales):

7. Overall:

   a Pass/Fail:

As you can see, I believe that currently this article fills all the criteria for a Good Article, and so I'm happy to pass it. As always with good articles, it is normally a good idea to suggest more improvements to make this article even better! So, here they are:

1. Just keep expanding! More content backed up with appropriate references will make this article better.

Thanks Smomo 23:57, 2 March 2007 (UTC)

Abraham Darby

At one point I may have removed the emphasis on Abraham Darby. He did not invent coke smelting. Pig iron had been produced with coke (or some mineral fuel) by Dud Dudley (to whom Darby was related) in the 1620s and again in the 1670s. Evidence also points to Shadrach Fox having used coke at Coalbrookdale in the 1690s. I have (I think) not written about Shadrach Fox in WP as some of it would be the result of unpublished original research. Abrham Darby's triumph was building a successful business casting cooking pots and other cast iron goods. This is no doubt why he obtained a patent for that and not for coke smelting. Furthermore, charcoal continued to be virtually the sole fuel for forge pig iron for consumption in finery forges until mid the 1750s. I thus think that the tone of the article should be altered, but would appreciate comments from other people before I do so. Peterkingiron 22:01, 13 March 2007 (UTC)

Cistercians

I am concerned at the prominence being given to the Cistercians in the article. I do not dispute that a case has been made that their General Chapter provided a mechanism of the diffusion of technology. However, the sources cited for this are at best rather general tertiary ones. I do not think they should appear so prominently in the introductory section. Furthermore, a rather more substantial academic publication should be cited: How the Catholic Church Built Western Civilization sounds like a polemical work, synthesising the work of others. Additionally, I suspect that the role of the Cistercians may still be controversial, but the article states this as if it is a well-known proved fact. The question of the blast furnace in medieval Europe is a topic on which evidence emerging has only started emerging in recent years. The requirement WP:NPOV makes me think that controversial views should not appear. Comments Please. Peterkingiron 22:22, 13 March 2007 (UTC)

Peter, you have my support (appears you're asking for a consensus) on both the points you just raised, particularly this one regarding the Cistercians. I'm always in support of NPOV improvements, and you have a very valid point. I say have at it! BSMet94 04:33, 14 March 2007 (UTC)

NPOV does not mean that certain views should not appear; it means that they should be given balanced coverage. I think we can remove or reword the section on the Cistercians from the lead, because their contributions did not have as long-standing an effect as, say, Darby or Neilson. However, the paragraph on the Cistercians under "Medieval Europe" should stay (as they were important for that time period), and it does not seem to state anything overly controversial. The Cistercians did facilitate the spread of metallurgy, but the argument is on whether this included efficient blast furnaces, and perhaps it could be reworded slightly to show it as an emerging theory. --Grimhelm 17:44, 14 March 2007 (UTC)

I do not seek to suggest that the references to the Cistercians should not appear, merely that they at present have excessive prominence. It is appropriate to include emerging views (if from peer-reviewed sources), as long as the fact that the are controversial or unproved is flagged up. I know that I have seen an article on the Cisterican General Chapter as a mechanism of the diffusion of technology, but do not now know where; I was hoping that this discussion might lead to some one identifiying this, so that a proper citation can be included. Peterkingiron 00:36, 15 March 2007 (UTC)

I have sought to tidy up this article, without significantly changing its content, mainly by trimming the introduction. I have placed the templete {{fact}} on the reference to the Cistercians. Material that I have read recently makes it clear that their expertise is well-accepted in certain academic circles, but this referes to France. What I have not yet seen is what their achievement is supposed to have been, nor am I clear that the map reproduced with the article actually shows is actually the spread of the blast furnace (as the caption implies), rather than the spread of the Cistercian order. T. Woods' book, which is the apparent source for this, appears to be a general work. Does some one have access to this; if so, can he indicate whether Woods cites sources on any site other than Laskill, and if so what? I do not think this article has yet reached a final form.

BSMet94 has indicated that blast furnaces were used for other metals. I have provided a heading on this, but this needs expansion. However I am not able to do this. Peterkingiron 16:08, 19 March 2007 (UTC)

Yes, I'll try to add some text on lead blast furnaces in about a week or so. In the early 20th century, say into the 20s or 30s, blast furnaces were used on certain copper ores. BSMet94 03:44, 20 March 2007 (UTC)

Woods does indeed cite a number of other sources for the Cistercians, and I have added sourced material that is more accepted (and less prone to change) than the Laskill case. It also explains better the achievement of the order in technological diffusion (such as in France as you point out) and as an international business, as well as the extent of machinery at each monastery. It does seem to indicate that the spread of the Cistercian order, as shown in the map, was quite closely linked to the spread of metallurgical technology and machinery "on a scale no civilization had previously known" (Gimpel). Given this, I feel we could add a short mention of this technological diffusion to the lead for "Iron". --Grimhelm 20:46, 20 March 2007 (UTC)

• I have removed the map which shows the spread of Cistercian monasteries (rather than of the blast furnace), as this is misleading: it tends to imply that a controversial view is an established one. As far as I can determine, there is no clear view yet as to the direction of spread of the furnace. The dates 1323 and 1380 given by Gimpel for the earliest furnaces represent an obsolete view.
• My problem in dealing with this subject is that what I have seen is largely reviews of books in the journal Technology and Culture, not the books themselves. This is much more recent work than Gimpel, who appears to be based on an article (not otherwise cited by him) in Revue d'Histoire de la Sidégurgie (who are credited for a map) in the Cistercians in Champagne. A book by a Swedish lady apparently asserts that the monks were not important in the trasnmission of technology to Sweden. Something else that I saw several years ago (but cannot now trace) claimed that the General Chapter of the Cistercians provided a mechanism for technology transfer. The discoveries in Switzland, the Mark (Germany) and Sweden have been made since Gimpel's book was first published in 1976, so that some of the views he expressed may be out of date.
• I have removed the citation of Gimpel for phosphate fertilisers from slag, because that is not in Gimpel's text, at least not at the point cited, leaving this as derived from Woods. However I have doubts as to the correctness of this: the use of basic slag as a fertiliser was a 19th century innovation, resulting from a process to remove phosperus from iron. I would be surprised if medieval bloomery slags were suitable, but I may be wrong. Peterkingiron 15:35, 23 May 2007 (UTC)