EST David Wilson Recarburiser Product Manager

Transcription

1 EST David Wilson Recarburiser Product Manager

2 Introduction History and technical background Traditional materials Customer environment and requirements Market trends and new developments Conclusion and predictions David Wilson Recarburiser Product Manager

3 What is a Carbon raiser? A Carbon Raiser, is a any carbonaceous material that is added to a molten ferrous alloy to adjust its melt chemistry. i.e. increase the percentage of Carbon

4 Carbon Usage: Iron and Steel Manufacturer of ferrous material, such as Steel works and Iron foundries, need to adjust the melt chemistry of their molten iron to achieve the required finished products. Carbon a key alloying element within iron and steel alloys and control of this primary relationship allows the ferrous metallurgist to dictate the properties of the finished material.

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6 It is clearly evident that ancient civilisations had a good understanding of the metals production and properties However it wasn t until René Réaumur postulated in 1722 that the amount of carbon is greatest in cast iron, less in steel, and least in wrought iron.

7 In the second half of the 18 th Century further work was carried out by Swedish scientists Scheele, Berman and Rinmann. They identified that the concentration of a substance they referred to as Graphite varied in wrought iron (0.05 to 0.2%), Steel (0.2 to 0.8%) and Cast Iron (1.0 to 3.3%) The French scientist Guyton de Morveau first conceived of steel as an Iron Carbon alloy in Although the form of the carbon remained a mystery.

8 Finally in 1868 D.K. Chernov established the existence of critical temperature points at which transformations occur in steel. This led to the modern Iron - Carbon phase diagram

9 Iron - Carbon Phase Diagram

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11 Iron - Carbon Phase Diagram

12 Iron Carbon: Carbon Equivalent To make matters more complicated other alloying elements also act as Carbon within iron and steel alloys. The are numerous equations describing the relationship between various alloying elements. For example, within cast iron the Silicon and Phosphorus contents are critical: CE = %C (%Si) (%P) 0.027(%Mn) + 0.4(%S) Or more simplified : CE = %C (%Si + %P) There are many more equations for steel alloys. However, I will not be focusing on these today.

13 So in summary, the Iron Carbon phase diagram allows metallurgists to predict the properties of a particular Iron (Steel) alloy. Control of Carbon is critical in the production of Iron (Steel) alloys

14 Where do we fit into this industry? EST. 1863

15 The James Durrans & Sons Limited was founded in 1863 in the British town of Penistone. The company has never strayed from its manufacture of foundry based, carbon-related products. Today the group has 10 manufacturing sites. We have 4 in the UK, 2 in Germany and 1 in China. In addition we have joint ventures in France, South Africa and India.

16 United Kingdom James Durrans & Sons Ltd. Carbon International France (JV) Carbon International SAS. China James Durrans (Tianjin) Coatings Ltd. Germany James Durrans GmbH South Africa (JV) Durrans RMS. India (JV) MPM-Durrans Refracoat Pvt. Ltd.

17 Since its establishment, James Durrans & Sons Ltd. has been at the forefront of providing carbon based products to a vast array of industries, which include: Steel manufacturers Iron, Steel and Non-Ferrous foundries Automotive, Rail and Aerospace Industries Power Generation, Transmission and Storage Refractory and Glass manufacturers Telecommunications, Utilities and Water Treatment Specialised Chemical Manufacturers Oil and Gas production Furnace and High Temperature equipment manufacturers

18 Finally something that makes us truly unique, is our Royal Charter issued by Queen Victoria

19 Where are they used?

20 A tale of two industries Steel Manufacturing Iron Foundries

21 The requirements of the steel manufacturing industry are quite different for those of Iron Foundries.

22 Steel manufacturers are very cost sensitive. To a large extent they are less concerned over the product s chemical analysis.

23 Although cost sensitive, this is not their prime focus. Product chemistry and consistency are critical to Iron foundries.

24 Although focusing on different aspects of the carbon raiser they all use the same standards by which to rate them. Chemical Analysis

25 % Ash % Volatile matter % Moisture % FIXED CARBON (100 Ash+Vol+Moist) % Sulphur % Nitrogen % Other trace elements

26 The concept of Fixed Carbon is an artificial one. It is purely a calculated approximation of a products purity. It does not take into account the presence Sulphur or Nitrogen (along with other elements).

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28 Anthracite Coal Metallurgical Coke Calcined Petroleum Coke Natural Graphite Synthetic Graphite

29 Major benefits: Readily Available (i.e. found all around the World) Relatively inexpensive (it s a raw mined product) Drawbacks Qualities depend on origins, temperature and pressure at formation Low solubility

30 Typical Specification Ash 3.5 to 20.0 % Volatile. 5.0 to 9.0 % Moisture. 0.5 to 1.0 % Fixed Carbon. 65 to 90 % Sulphur. 0.5 to 1.0 % Nitrogen 0.3 to 0.8 %

31 Major benefits: Readily Available (i.e. found all around the World) Inexpensive Drawbacks Qualities depend on origins of the coals and coking process quality. Limited availability due to demand by other industries Relatively low solubility

32 Typical Specification Ash 8.5 to 20.0 % Volatile. 1.0 to 3.5 % Moisture. 0.5 to 1.0 % Fixed Carbon. 65 to 90 % Sulphur. 0.8 to 1.5 % Nitrogen 1.0 to 2.5 %

33 Major benefits: Consistency of a manufactured product Low impurities (i.e. high fixed carbon) Drawbacks Limited supply Qualities depend on origins of the oils and blend quality Limited availability due to demand from other applications

34 Typical Specification Ash 0.1 to 0.5 % Volatile. 0.2 to 0.5 % Moisture. 0.1 to 0.5 % Fixed Carbon to 99.5% Sulphur. 0.3 to 1.8 % Nitrogen 0.6 to 2.0 %

35 Major Benefits Naturally occurring around the World. High solubility Drawbacks Limited availability due to demand from other applications Relatively low Fixed Carbon

36 Typical Specification Ash 4.0 to 11.0 % Volatile. 2.0 to 4.0 % Moisture. 0.1 to 0.5 % Fixed Carbon to 92.0% Sulphur. 2.0 to 3.0 % Nitrogen 1.5 to 2.0 %

37 Major Benefits Consistency of a manufactured product Very low impurities (i.e. high fixed carbon) Drawbacks Limited availability due to demand from other applications High costs due to lengthy and expensive manufacturing process

38 Typical Specification Ash 0.1 to 1.0 % Volatile. 0.1 to 0.5 % Moisture. 0.1 to 0.5 % Fixed Carbon to 99.5% Sulphur to 0.10 % Nitrogen 0.01 to 0.10%

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40 Steel manufacturers are extremely cost sensitive (Fixed carbon per unit of currency) Volumes are very high, measured in the hundreds of tonnes per month Less sensitive to impurities Due to the temperatures involved, solubility is less of an issue

41 Carbon Raisers for Steel works Anthracite Coal Ideal for bulk charge Metallurgical Coke Cal. Petroleum Coke Natural Graphite Synthetic Graphite Ideal Trim additions Short supply Relatively expensive Trim additions Relatively expensive

42 Iron foundries tend to focus of consistency and chemical purity Volumes are can be high, measured in the truck loads per month Sensitive to impurities Solubility can be a major factor

43 Carbon Raisers for Iron Foundries Anthracite Coal Not used Metallurgical Coke Cal. Petroleum Coke Natural Graphite Synthetic Graphite Poor solubility limits use Ideal Expensive and in short supply Ideal, but relatively expensive

44 Iron foundries fall into two groups Ductile (SG) Iron foundries are sensitive to sulphur content Grey Iron foundries tend not to be sensitive to sulphur content

45 Grey Iron foundries Tend to be more price sensitive Solubility and consistency (performance) is critical in a volume foundry no time to make corrections Sulphur levels not critical but ideally between 0.5 and 1.2%

46 Ductile Iron foundries Price is important, not critical Solubility and consistency (performance) is critical in a volume foundry no time to make corrections Sulphur levels critical, ideally < 0.1%

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48 Looking back at the list of traditional materials: Anthracite Coal Metallurgical Coke Calcined Petroleum Coke Natural Graphite Synthetic Graphite

49 In recent years additional products have gained market share from the traditional ones: Calcined Anthracite (gas or electric) Pelletized materials Graphitised Petroleum Coke Pitch Coke Bespoke blends of carbon materials Organic and Reclaimed materials

50 Major Benefits Consistency of a manufactured product Readily available Relatively inexpensive Relatively low sulphur (approx. 0.2%) and volatile (<0.8%) Drawbacks Limited by Ash content (approx. 4.0%) Limited by solubility Uses In Steelworks Main use as a blending material

51 Major Benefits Consistency of a manufactured product Inexpensive Relatively low sulphur & Nitrogen (approx. 0.6% for each) Drawbacks Limited by solubility (hard, no porous surface) Limited available due to suitable feedstock Uses Steelworks Grey Iron foundries

52 Major Benefits Consistency of a manufactured product Relatively inexpensive Low Sulphur & Nitrogen (approx. 0.1% for each) Drawbacks Limited by fixed carbon content (i.e. High Ash and Volatile) Limited by solubility (hard, no porous surface) Limited available due to suitable feedstock Uses Steelworks Large SG producers

53 Major Benefits Consistency of a manufactured product High purity, low Sulphur & Nitrogen (0.05% for each) High solubility and graphitic nature Drawbacks Limited availability High energy production costs (2.5 MW per tonne) Environmental concerns Sulphur emissions Uses Steelworks SG Iron foundries

54 Major Benefits Consistency of a manufactured product Good Sulphur content (approx. 0.5%) Good solubility Drawbacks Limited but increasing availability Uses Steelworks Iron foundries

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56 Many producers are now providing their customers with bespoke blends of the materials already discussed. These benefit the customer with a seemingly ideal carbon chemical analysis. However, blends are manufactured with materials of varying solubility. The resulting jumps in Carbon recovery lead to an inconsistent melt practice and constant late trim adjustments.

57 The sheer availability of waste organic materials has led to them being used as carbon additions to ferrous metals. Crushed coconut shells and spent rice husks being the most commonly encountered. Although these have relatively low Sulphur contents, and extremely cheap, they have very high ash levels. This translates into large amounts of unwanted furnace slag, which can become inclusions within the finished product.

58 Finally, reclaimed carbonaceous materials such as spent anodes and reclaimed tyres. To date, the available materials tested have been shown to contain high volatile contents (>2.0%) and are generally inconsistent. In the case of spent anodes, there also remains concern over the potential of residual salt and heavy metal contamination. These materials are currently not in significant use.

59 However, with todays focus on recycling technologies, these manufacturing processes are likely to undergo improvements. It is difficult to predict whether these materials will have a place in the future. They are certainly not up to the required standard yet.

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61 Carbon Raisers: (approximate values) Index: 1 = Best, 9 = Worst Type of Carbon Fixed Carbon Sulphur Ash Volatile Moist. Solubilty Index Avail. Index Cost Index High Purity Synthetic Graphite Synthetic Graphite Graphitised Pet Coke Low Sulphur Pet. Coke Low Sulphur Pellets Calcined Anthracite Natural Graphite Medium Sulphur Pet. Coke Med. Sulphur Pellets Pitch Coke Metallurgical Coke Anthracite Coal

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63 Clearly Steel making has been in the spotlight of the media recently. With the current excess availability of Steel, the worlds prices have fallen dramatically. This has clearly put pressure on all manufacturers and therefore suppliers. However, most steel manufacturers already utilise very low cost materials, so this already competitive market is going to get very congested.

64 Iron foundries also face a very tough time which will impact on their usage of materials. Many are already exploring alternatives to their traditional materials in a hope of either improving their processes (reducing scrap), by lowering their overall costs (reduction in time) or by helping to meet their environmental obligations. This is good news for some

65 However, most iron foundries are so short staffed that they physically find it difficult to justify changes to the practices or to carry out trials. This is combined with the reluctance of their customers to accept process changes (specifically Automotive) unless there is good reason. New suppliers must offer the potential of significant reductions in order to merit the workload of trials. However, given that so many other materials are reducing in price, the pressure on carbon (a relatively small spend) is reduced.

66 So finally there is some light at the end of the tunnel. Global oil process continue to remain low, impacting on the cost of manufacture of carbonaceous product. There is also increasing environmental pressure on manufacturers to improve their output. This will hopefully impact all.

67 Looking more specifically at Graphite. Steel manufacturers seem unlikely in the future to look towards graphite as a Carbon raiser given the price, quality and availability of the alternative materials. However, Graphite, or at least Graphitic materials, remain an important go to material for Iron foundries. The technical benefits offered by Graphite over the alternatives remain clear, but they come at a financial cost.

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69 I hope that I have demonstrated that the current market place for Carbon Raisers is diverse and extremely competitive. Looking forward graphite, specifically synthetic graphite, is likely to retain a small market share of the carbon raiser sector. However this will most likely be focused on niche markets where purity and solubility are critical.

70 David Wilson Recarburiser Product Manager James Durrans and Sons Limited EST. 1863