ADDITION OF RENEWABLE CARBON TO LIQUID STEEL: PLANT TRIALS AT ONESTEEL SYDNEY STEEL MILL M. A. Somerville 1, M. Davies 2, J. G. Mathieson 3, P. Ridgeway 4 and S. Jahanshahi 1 1 CSIRO Minerals Down Under Flagship Box 312 Clayton South, VIC, 3169, Australia michael.somerville@csiro.au 2 OneSteel Market Mills, PO Box 700, Rooty Hill NSW, 2766 3 BlueScope Steel Research, PO Box 202, Port Kembla NSW 2505 4 OneSteel Limited, PO Box 156, Newcastle NSW 2300 ABSTRACT The Australian steel industry has been actively examining alternative technologies for reducing energy consumption and net greenhouse gas emissions. In Australia, the option of using renewable carbon derived from biomass has been investigated through a collaborative R&D program supported by BlueScope Steel, OneSteel and CSIRO. The present work is part of this program and involved production of charcoal recarburiser and subsequent plant trials to evaluate the performance of this material against conventional fossil carbon based recarburiser for addition to liquid steel. In a series of 12 production heats at OneSteel Sydney Steel Mill, specially prepared charcoal with very low volatile and moisture content, was added to 80 tonne ladles of liquid steel. This trial also considered 18 heats where conventional, fossil carbon based recarburiser was used as a comparison. A statistical analysis was used to compare the carbon recovery and hydrogen pick-up to the liquid steel. The results show that the use of charcoal resulted in an increase in the average carbon recovery. This difference was not statistically significant. A slight increase in hydrogen pick-up to liquid steel was observed with charcoal use, but this difference was not significant. Physical properties which are important for the handling and processing of the charcoal, including density and water adsorption, were addressed during the trial and are important considerations for commercialisation of this process. The trial showed that renewable carbon sourced from biomass was a feasible alternative to fossil carbon in the recarburisation of liquid steel. INTRODUCTION The Australian steel industry is interested in expanding the use of renewable carbon in iron and steel making operations for the twin benefits of reducing net CO 2 emissions and reducing the effect of a carbon price on company finances. The Australian steel industry produces about 8 million tonnes of steel per year (ABARE, 2010). In producing this steel about 14 million tonnes of CO 2 is released, mostly through the use of coal and coke in the reduction process. Although low by world standards this still represent between 2 and 3 % of Australia s green house emissions (Australian GHG Office 2010). The likely impost of a carbon price in the near future will increase the cost of fossil carbon and add cost pressures to the steel making process. The use of renewable carbon in the form of charcoal derived from sustainable biomass could minimise net CO 2 emissions and help relieve these cost pressures.
In 2006 BlueScope Steel, OneSteel and CSIRO initiated a collaborative project with the broad aims of identifying, evaluating and demonstrating applications of renewable carbon use in the steel making production chain. This project was originally supported by the Centre for Sustainable Resource Processing (CSRP) and forms part of Australia s contribution to WorldSteel s CO 2 Breakthrough program (Jahanshahi, 2008 and WorldSteel 2009). This project has three main parts: 1. The identification and quantification of suitable sustainable biomass resources 2. The processing of biomass into a form which can be used by the iron and steel industry. The process where biomass is transformed into charcoal is called pyrolysis. Control of the pyrolysis process is necessary to produce charcoal with the required properties for particular iron and steel making processes. 3. The use of charcoal in different iron and steel making processes such as iron ore sintering, coke making, solid fuel injection into blast furnace, electric arc furnace (EAF) slag foaming agent, charge carbon and a liquid steel recarburiser. Opportunities for charcoal use in steelmaking Recently Mathieson (2010) investigated the potential for charcoal use in steel making. They considered both an integrated steel works such as BlueScope Steel s operation at Pt Kembla (NSW) and OneSteel s operation at Whyalla (SA) as well as EAF operations such as at Laverton (Victoria) and Rooty Hill (NSW) and Waratah (NSW). For each potential application the possible substitution of charcoal for coal and/or coke was estimated and hence the potential saving of CO 2 emissions per tonne of crude steel was calculated. These results are summarised in Figure 1 for an integrated steel works and in Figure 2 for an EAF operation. The initial segment of each bar represents the minimum substitution currently believed to be feasible, while the full length is the maximum possible. It will be noted that, for the integrated steelmaking process, over 50% of the current 2.2 t-co 2 /t-crude steel can be addressed, but only around 10% of the current 0.6 t-co 2 /t-crude steel can be substituted in the case of EAF steelmaking. This is because around 88% of EAF emissions are associated with generation of the electricity used, i.e. a further 0.53 t-co 2 /t-crude steel could be saved if the electricity supply was based on zero carbon technologies. The calculations used to produce the data in Figures 1 and 2 assumed the following: Coke, coking coal blends, recarburiser, sintering solid fuel, EAF foaming agents, EAF charge carbon and total charcoal contained 85 % carbon BF tuyere injectant coal contained 75 % total carbon Charcoal can be directly substituted for coal and coke on an equivalent carbon basis Possible process efficiencies associated with the use of charcoal in iron and steel making are not considered The technical issues associated with charcoal use in iron and steel making, such as transport and grinding, are solved The biomass required to produce the necessary charcoal is available. 2
Steelmaking recarburiser (0.25 kg/t-crude steel) Cokemaking blend component (2-10%) BF pre-reduced feed (5-10%) BF nut coke replacement (50-100%) 6% 14% Sintering solid fuel (50-100% replacement) 19% 25% BF tuyere injectant (150-200 kg/t-hm) 32% 54% Total Min Max 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Net Emissions Saved (t-co 2/t-crude steel) Fig. 1: Possible reductions in CO 2 emissions through charcoal substitution for coal and coke in an integrated steelmaking process (Mathieson, 2010). Natural gas heating (0%) Scrap, electrodes, etc (0%) Steelmaking recarburiser (50-100%) Slag foaming agent (50-100%) Charge carbon (50-100%) Total 5.90% 11.50% Min Max 0.00 0.01 0.02 0.03 0.04 0.05 0.06 Net Emissions Saved (t-co 2/t-crude steel) Fig. 2: Possible reductions in CO 2 emissions through the substitution of charcoal for coal and coke in an EAF steelmaking process (Mathieson, 2010). A key to widespread use of charcoal in the steel industry is the production of charcoal with the physical and chemical properties required for the specific application. For example, steel recarburisation requires charcoal with very low ash, volatile and moisture contents. Iron ore sintering requires charcoal with a low reactivity, while charcoal as a blast furnace injectant is optimised with a relatively high volatile content and reactivity. The production of charcoal with known properties requires careful control of the charcoal production process. Recent research work conducted at CSIRO has shown that charcoal has many advantages in iron ore sintering (Lovel et al 2009), although control of charcoal reactivity is required to minimise fuel requirements and optimise sinter strength. Through the careful control of charcoal properties, other applications such as a blast furnace tuyere injectant could also be possible (Mathieson et al 2007; Mathieson (2010); Rogers and Mathieson 2010 and Mathieson 2011). 3
This paper is concerned with the third part of the project, i.e. the use of charcoal in steel making, specifically the process of recarburisation. This is the addition of carbon, in this case renewable carbon, to refined liquid steel in order to produce steel of a required grade. In the structure and timing of the overall project, recarburisation was chosen as the first demonstration of renewable carbon use in steel making despite having a relatively small contribution to total CO 2 emissions. It was thought that this application was relatively simple and easy to observe despite requiring a high quality charcoal product. This study would also be a good initial investigation of the logistical and charcoal quality issues which would be required for a commercial charcoal supply. Preliminary small scale recarburisation investigations were carried out at the Clayton laboratories of CSIRO using kg scale equipment previously described by Langberg et al (2006). Results of these experimental investigations were reported by Somerville et al (2010). Following the success of this preliminary work, plant scale investigations were carried out at the OneSteel Sydney Steel Mill (SSM) during 2009. Specially prepared charcoal was directly added to 80 tonne ladles of liquid steel at the ladle metallurgy furnace (LMF) and at tapping of the electric arc furnace (EAF). The performance of the charcoal was compared to conventional fossil carbon based recarburiser on a heat-byheat basis. The basis of comparison was carbon recovery from recarburiser to steel and hydrogen pick up by steel. The kinetics of charcoal dissolution in liquid steel was also investigated. LARGE SCALE CHARCOAL MAKING Materials and procedure Five coke ovens from the east beehive battery of the Corrimal works of the Illawarra Coke Company were used to convert the 20 tonnes of wood, supplied in 20 bundles, into low volatile charcoal. The charcoal making commenced when 4 bundles were fed into each of 5 selected empty coke ovens using a forklift. A thermocouple was inserted into the last bundle of each oven and was used to monitor the temperature during heat up and pyrolysis of the wood. At the end of pyrolysis the charcoal was removed from each oven using a ram which pushed the charcoal into the waiting bucket of a larger front end loader. The charcoal was then dumped into a large steel bin where it was quenched with water. The aim of the test was to allow the wood to reach 1000 C before pushing and subsequent quenching of the charcoal. The results of the previous drum testwork indicated that this should occur within approximately 2 hours. During the testwork the state of the ovens was also monitored, in particular the amount of flames from the combustion of volatile components of the wood was noted. The temperature of the fourth (last charged) bundle of wood from each oven was monitored during the charcoal making run. Grab samples of the quenched charcoal from each oven were collected and analysed by HRL Ltd (Melbourne, Victoria). These grab samples were selected from the charcoal pile, not riffled and so are not necessarily representative of the charcoal produced from the oven and may be considered as better quality charcoal from each batch. Proximate analysis results of these charcoal samples are shown in Table 1. These results show that the target volatile content of the charcoal 4
(less than the 1 %) was reached. The ash content was generally less than 1 %, but the charcoal from Oven 4 contained 1.6 % ash. The average ash content was 0.85 %. Tab. 1: Proximate analysis of charcoal samples collected from each coke oven. Sample Volatiles Ash Fixed Carbon (%db 1 ) (%db 1 ) (%db 1 ) Oven 1 0.83 0.83 98.3 Oven 2 0.80 0.73 98.5 Oven 3 0.29 0.63 99.1 Oven 4 <0.01 1.59 98.4 Oven 5 <0.01 0.48 99.5 1. db = dry basis Figure 3 shows the temperature readings for each oven during the charcoal making. The x-axis shows the time after the final bundle addition for each oven. The typical behaviour evident from Figure 3 is a rapid increase in temperature to about 400 C, followed by a plateau of about 3 hours and finally an increase in temperature to approach the oven temperature of about 1000 C. The temperature of one oven (2) remained stubbornly low, but still displayed the temperature plateau albeit at a lower temperature than the other ovens. The reason for this lower temperature is not known but is likely to be due either to the position of the thermocouple in the wood bundle, or the partial collapse of the bundle. Temperature ( C) 1200 1000 800 600 400 Oven 5 Oven 4 Oven 3 Oven 2 Oven 1 200 0 0 1 2 3 4 5 6 Time from charging oven (h) Fig. 3: Temperature of the wood in each oven during charcoal making. The time required for the wood/charcoal to reach the target temperature of 1000 C was much longer than expected. After approximately 4 hours the initial vigorous gas release and flaming of the wood bundles had slowed considerably. This was assumed to indicate that the rate of volatile release from the wood was decreasing and that the wood/charcoal volatile content was fairly low. The temperatures of the ovens had also started to increase after a long stable period. The final measured temperatures of the charcoal prior to pushing of the oven were: 990, 600, 850, 660, and 930 C for ovens 1, 2, 3, 4, and 5 respectively. 5
Charcoal handling The charcoal prepared at Corrimal was dried, crushed and packaged in readiness for the recarburisation trials. The final material was dry, low volatile charcoal in the 1-5 mm size range. Measured 2.5 kg batches of this charcoal were packed into snap locked plastic bags which were flooded with nitrogen gas. Two of these bags were loaded into a plastic lined cement bag and sealed using a hot liquid glue gun. Figure 4 shows a photograph of the 5 kg charcoal bags used in the trial. Also shown is a 10 kg bag of the bulk conventional recarburiser. This comparison illustrates the reduced density of the charcoal compared with conventional recarburiser. The bulk density of the conventional recarburiser was about 1000kg/m 3 while the bulk density of the charcoal was about 250 kg/m 3. This difference in bulk density creates manual handling issues as the charcoal packages are manually added to the ladle at the LMF. Fig. 4: Photograph of two 5 kg bags of charcoal bags used in the recarburisation trial along with 10 kg bags of conventional recarburiser. RECARBURISATION TRIAL AT SSM SSM Melt Shop Operations The Melt Shop at Sydney Steel Mill has a production capacity of more than 600,000 tonnes of prime steel billet per annum. Recycled steel scrap supplemented with iron feed is melted in a high power EAF, treated at an LMF and cast into steel billets using a continuous billet casting machine. Billets are then rolled into rod and bar products for supply to various Australian industries including construction, mining and agriculture. The EAF process begins with the charging of approximately 90 tonnes of steel scrap. A small amount of lump coke or blast furnace iron is added for chemistry control. The charge is melted by an electric arc established between three graphite electrodes inserted through the roof of the furnace. Dolomite and lime are added to create a slag and to protect the furnace refractory hearth and sidewalls. Oxygen and coke are blown through a water-cooled lance to refine the liquid steel and condition the furnace slag. After melting and refining, the liquid steel in the furnace is tapped into a ladle. 6
The full ladle is then transferred to the LMF, where adjustments to steel chemistry and temperature are made before casting. Argon gas is bubbled through a porous plug in the bottom of the ladle at between 60 and 80 L/min (STP) and is used to mix and homogenise the steel. Samples of steel are collected and analysed by the LMF Operator using a spark based optical emission spectrometer. Additions of recarburiser and alloying elements are made to the ladle according to the results of this analysis and the grade of steel being produced. After the target steel chemistry and temperature are achieved the ladle is taken to the Billet Caster where the steel is continuously cast into billets. The majority of alloy and carbon additions are made to the steel ladle during tapping, due to the good mixing provided by the tapping stream. Trim additions are added at the LMF to achieve the steel grade specification. Carbon, which is used to strengthen and harden the steel, is currently added using a commercial recarburiser. The recarburiser is a 1-5 mm dry granular material supplied in 10 kg paper bags. The bags are manually added to the bottom of the empty ladle before tapping and later to the full ladle at the ladle furnace. The additions at the LMF are made to the bubbling eye which is a window of exposed liquid steel in the liquid/solid slag of about 40cm diameter. The bubbling eye is generated by a plume of argon gas which is injected through a porous plug at the base of the ladle. Table 2 shows the proximate analysis of the charcoal and commercial recarburisers. During the recarburisation trial normal Melt Shop operations were followed. The trial involved heats made with both conventional recarburiser and charcoal recarburiser. In both cases, bags of recarburiser were added manually to the eye of the liquid steel in the ladle. These additions were made soon after an initial analysis of the steel was available. The amount of recarburiser added to the steel ladle was determined by the steel grade being produced, i.e. a higher grade of steel required more recarburiser. In addition to standard measurements, the hydrogen content of the liquid steel was determined in-situ using a Hydris unit provided by Hereaus-Electronite (Hurst 2009). These measurements were applied to both the conventional heats and the heats which used charcoal. During the trial normal plant operations were maintained. However, on some occasions a fast production rate at the caster meant that insufficient time was available for all of the desired measurements to be taken before the ladle was moved on. Table 3 shows a summary of the trial heats and the type and locations of carbon additions to the ladle. Tab. 2: Proximate analysis of the commercial and charcoal recarburiser used in the recarburising trial. Recarburiser Moisture (%ar 1 ) Volatiles (%db) Ash (%db) Fixed carbon (%db) Commercial recarburiser 0.7 0.4 4.7 94.9 Charcoal recarburiser 2.3-2.8 1.9 2.1 96.0 1 ar = as received 7
Tab. 3: Summary of the steel heats used in the recarburisation trial (CR = commercial recarburiser). Recarburiser type Recarburiser type Heat Heat EAF Ladle EAF Ladle No. No. tapping furnace tapping furnace 94 CR CR 106 CR CR 95 CR CR 107 CR CR 96 CR CR 108 CR Charcoal 97 CR CR 109 CR Charcoal 98 CR Charcoal 110 CR Charcoal 98a CR CR 111 CR CR 99 CR Charcoal 112 CR CR 99a CR CR 113 CR CR 100 CR Charcoal 114 CR Charcoal 100a CR CR 115 CR Charcoal 101 CR CR 116 CR Charcoal 102 CR CR 117 Charcoal Charcoal 103 CR CR 118 Charcoal Charcoal 104 CR CR 119 CR CR 105 CR CR 120 Charcoal Charcoal Uncertainty factors in conducting plant scale investigations. The following minor difficulties were encountered when conducting the trial at Sydney Steel Mill; these would be expected with any steel producing facility. 1. The length of time a ladle was held at the LMF was not constant and varied depending on the requirements of the continuous caster. 2. The calculation of carbon recovery is based on carbon in steel analysis. A small uncertainty in the reported carbon content of 0.001 % will change the apparent carbon recovery by 2.6 %. Variations in the measured ladle weight, due to refractory wear, will also add some variability to the measured carbon recovery. 3. Variations in the size of the argon bubble will change the surface area through which the recarburiser is added and dissolves. Charcoal landing on the slag layer will dissolve more slowly or may simply be trapped on the slag layer and not dissolve. This was observed in a number of heats, particularly earlier in the trial. For these reasons the basis of comparison of charcoal recarburiser with the conventional fossil carbon based material was the average carbon recovery or hydrogen pick up over a number of heats. The T statistical distribution was used to compare the mean of the two sets of experimental data. The comparison was based on the 0.2 level of significance. Carbon recovery The recovery of carbon to liquid steel can be calculated, for each heat of steel produced, from: the weight of recarburiser added the carbon content of the recarburiser 8
the weight of liquid steel in the ladle the initial carbon content of the steel, i.e. before LMF recarburiser addition the final carbon content of the steel, i.e. after LMF recarburiser addition and allowance for the liquid steel to homogenise. This information was obtained from SSM plant log sheets and various material analyses. The calculated carbon recovery data are shown in Figure 5 where the calculated recovery is plotted against heat number. On a small number of heats the apparent carbon recovery to liquid steel is unrealistically high and sometimes is greater than 100 %. This high apparent recovery is most likely due to small errors in the weight of liquid steel which is based on a calculated weight. When the trial is considered as a whole, 18 heats involved the addition of commercial recarburiser and 12 heats used charcoal as the recarburiser. The overall average carbon recovery to liquid steel at the LMF was 67.8 % for the commercial recarburiser and 86.4 % for charcoal. However this difference is not statistically significant at the 0.2 level. Carbon recovery to liquid steel (%) 100 80 60 40 Commercial recarburiser Charcoal 20 90 95 100 105 110 115 120 125 Heat Number Fig. 5: Plot of carbon recovery to liquid steel for heats used in the charcoal recarburisation trial. The plot shows a comparison between heats where charcoal and commercial recarburiser were used. Hydrogen pick up The hydrogen content of steel can increase during recarburisation due to moisture in the carbon materials and alloys being added to the ladle. The moisture content of charcoal recarburiser was between 2.3 and 2.8 % while the commercial recarburiser contained about 0.7 % moisture. Hence there was some expectation of increased hydrogen pickup into steel for those heats where charcoal was used. 9
The hydrogen pick-up into steel was determined from the difference between the initial hydrogen content of steel, measured before recarburiser addition and the final hydrogen content after recarburiser addition. The hydrogen content was determined in-situ using the Hydris unit. On a number of heats a final Hydris measurement was not possible due to production constraints and the need to quickly send the ladle to the caster. Figure 6 shows a plot of hydrogen pick-up for each applicable ladle heat. Hydrogen pick up by steel (ppm) 2.0 1.5 1.0 0.5 0.0-0.5 Commercial recarburiser Charcoal -1.0 90 95 100 105 110 115 120 125 Heat Number Fig. 6: Plot of hydrogen pick-up by molten steel during recarburisation at the ladle furnace Taking the recarburisation trial as a whole, the average hydrogen pickup by steel for heats where commercial recarburiser was used was 0.37 ppm. When charcoal was used the average hydrogen pick-up by steel was 0.57 ppm. This difference was found not to be statistically significant at the 0.2 level and, in any case, is not metallurgically significant. For a typical ladle heat which contained 81.5 tonnes of steel and where 80 kg of charcoal recarburiser was added which contained 2.5 % moisture, the hydrogen content of steel could be expected to increase by 2.7 ppm if all the hydrogen contained within the recarburiser was captured by the steel. For the commercial recarburiser containing 0.67 % moisture the maximum pick-up of hydrogen by molten steel would be 0.74 ppm. The actual maximum hydrogen pick-up will depend on the efficiency of hydrogen transfer between moisture and liquid steel. In this work the hydrogen transfer efficiency was found to vary from about 40 to 70 %. Rate of carbon dissolution The rate of charcoal dissolution into liquid steel can be calculated from the analysis of steel samples collected at regular intervals after the addition of recarburiser at the LMF. In some heats during the trial steel samples were collected at 1, 3 and 5 minutes after recarburiser addition. Additional samples were sometimes available from the routine plant samples which were used by plant operators to calculate the amount of recarburiser to add to the ladle. Typical charcoal dissolution behaviour is shown in 10
Figure 7. This is a plot of the amount of carbon dissolved in the liquid steel plotted against the time since recarburiser addition. Figure 7 shows that most of the recarburiser dissolves in the first minute. This rapid increase in the amount of carbon dissolved in steel is followed by a longer period where the carbon increase is more gradual. This pattern is followed, more or less, in most of the ladle heats. Most heats show an initial fast rate of carbon dissolution of between 17 and 33 kg/min. After the first minute, the rate decreases to between 5 and 12 kg/min. The carbon recovered within the first minute is between 36 and 67 % of the total carbon recovery. Within the third minute, between about 50 and 100 % of the total carbon added as recarburiser has been recovered to the steel. Amount of carbon dissolved into steel (kg) 40 35 30 25 20 15 10 5 50 kg charcoal added 0 0 2 4 6 8 10 12 Time (minutes) Fig. 7: Typical plot of the mass of carbon dissolved in steel plotted against time. CONCLUSIONS A successful campaign of recarburisation plant trials was conducted at the Sydney Steel Mill. The charcoal recarburiser was shown to be at least as effective as the conventional material at recarburising steel. The results showed that charcoal resulted in a slightly higher average carbon recovery to steel and a slightly higher hydrogen pick-up, although these differences were not statistically or metallurgically significant. Future work will focus on the density of charcoal products to reduce specific transport costs and control charcoal reactivity and ways to minimise moisture pick up. 11
ACKNOWLEDGEMENTS The authors wish to acknowledge the support and cooperation of the following: The management and staff of the OneSteel Sydney Steel Mill to allow the recarburisation trial to take place. The management and staff of the Corrimal coke works of Illawarra Coke Company which allowed the preparation of charcoal used in the trial. Peter Davies from Colinton NSW for the supply of the wood used to make the charcoal. The technical staff of CSIRO Process Science and Engineering and of BlueScope Steel Research for assistance in the sorting, drying and packaging of the charcoal. This work was carried out with some financial support from the Centre for Sustainable Resource Processing (CSRP), which was established and supported under the Australian Government s Cooperative Research Centres Program. The authors also acknowledge the financial support provided by BlueScope Steel, OneSteel and the CSIRO Minerals Down Under Flagship. REFERENCES ABARE Australian mineral statistics, available from (www.abare.gov.au/), [accessed 4 January 2010]. Australian national greenhouse gas inventory, available from (http://ageis.climatechange.gov.au/) [accessed 4 January 2010]. Hurst C J, 2009, Gas analysis in steel: identifying, quantifying and managing hydrogen pick-up in steel, available from (www.aomevents.com/conferences/afi/papers/hurst.pdf) [accessed August 2009]. Jahanshahi S, Mathieson J G, Ridgeway P, Somerville M, Xie D and Zulli P, 2008, Australian contribution to the IISI (WorldSteel Association) CO 2 program, presented to 2 nd International Symposium of Sustainable Iron Making, September 2008 (SMaRT: UNSW). Langberg D E, Somerville M A, Freeman D E and Washington B M, 2006, The use of Mallee charcoal in metallurgical reactors, in proceedings Green Processing 2006, pp 69-75 (The AusIMM: Melbourne). Lovel R R, Vining K R and Dell Amico M, 2009, The influence of fuel reactivity on iron ore sintering, ISIJ International, Vol 49, No 2, pp 195-202. Mathieson J G, 2007, The value-in-use of some biomass derived blast furnace injectants, BlueScope Steel unrestricted technote BSR/N/2007/071. Mathieson J G, 2010, The potential for utilisation of biomass and carbonaceous wastes to replace coal, coke and coal-based chars in ironmaking and steelmaking, BlueScope Steel unrestricted technote - BSR/N/2010/01 Mathieson J G, Rogers H, Somerville M, Ridgeway P and Jahanshahi S, 2011, Use of biomass in the iron and steel industry an Australian perspective, in proceedings 1 st International conference on energy efficiency and CO 2 reduction in the steel industry, June 2011, Dusseldorf, Germany. 12
Rogers H and Mathieson J G, 2010, Combustion tests to determine the suitability of charcoal and coal-charcoal blends as blast furnace injectants, BlueScope Steel unrestricted report BSR/R/2010/001 Somerville M, Jahanshahi S, Ridgeway P, Davies M and Mathieson J G, 2010, Sustainable carbon in steelmaking plant trials at the Sydney steel mill, in proceedings Sustainable Mining, pp 38-52, (The Australasian Institute of Mining and Metallurgy: Melbourne). WorldSteel, 2009, 10 th WorldSteel CO 2 Breakthrough meeting, August 2009, Dusseldorf, Germany. SPEAKERS BIOGRAPHY Michael Somerville is a Research team leader with CSIRO Process Science and Engineering. Prior to joining CSIRO he worked in Industry in a variety of operating and plant improvement positions. Over the past 18 years he has worked on sponsored projects at CSIRO designed to improve the economic and environmental performance of pyrometallurgical processes. Recent work has focused on the use of renewable carbon in metallurgical processes. This work includes the development of sustainable solid fuels and reductants based on transformed biomass or charcoal as replacements for fossil coal and coke. At present Michael is leading a CSIRO project team on collaborative projects with OneSteel and BlueScope steel on the use of biomass in the iron and steel industry as a way of reducing greenhouse emissions. 13