OPERATIONAL RESULTS AT NUNKI STEEL

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1 NOVEMBER 2012 POLYMER INJECTION TECHNOLOGY ONESTEEL NSW Pty Ltd appoints world-leading supplier MORE to promote Polymer Injection. OPERATIONAL RESULTS AT NUNKI STEEL Nunki Steel S.p.A. is located in San Giorgio di Nogaro (UD), Italy, and produces an extensive range of specialty steel products. NEW WORKSHOP INVESTMENT MORE has invested in state of the art CNC machining and turning centres.

2 NOVEMBER 2012 N 1 POLYMER Recycled tires to produce foaming slag in the EAF steel making process INJECTION TECHNOLOGY ONESTEEL NSW Pty Ltd appoints world-leading supplier MORE to promote Polymer Injection. MORE and OneSteel have agreed to co-operate to promote Polymer Injection to leading steelmakers around the World. MORE will be OneSteel s preferred supplier for EAF steel-making solutions packages. The two companies will be working to develop new solutions in the field of steelmaking. Polymer Injection, developed by OneSteel in collaboration with the University of NSW (Sydney-Australia), utilizes recycled tires and other polymers to improve the properties of foaming slag, enabling EAF steelmakers to reduce injected carbon costs, decrease electrical energy consumption, improve yields and help the environment by diverting tires from the landfill. This Australian invention further reinforces the green credentials of the electric arc furnace produced steel. How it works In conventional EAF steelmaking, injection of carbon produces foaming slag which covers the molten steel during the melting process. Polymer injection technology provides benefits to EAF steelmakers by improving the foaming properties of the slag, using a blend of polymer and carbon. A combination of rubber and anthracite produces a superior foaming slag volume than anthracite alone. Established process OneSteel has conducted extensive testing that shows that the use of polymer injection technology has no adverse effect on steel quality or to the environment and over heats have been performed with this technology in operation so far. Benefits Reduced electrical energy consumption Reduced transformation costs Reduced emissions levels Improved productivity Improved slag foaming

3 NEWS FROM THE STEELMAKING WORLD OPERATIONAL RESULTS AT NUNKI STEEL MODULE TECHNOLOGY IN OPERATION FOR SPECIAL STEEL PRODUCTION Nunki Steel S.p.A. is located in San Giorgio di Nogaro (UD), Italy, and produces an extensive range of specialty steel products. The steel grade range includes low / medium / high alloy, carbon, chromium alloy, chromium-molybdenum, ferritic alloy for high-pressure / temperature, which are cast into ingots with a maximum weight of 170 tons. The meltshop operates with an AC spout electric arc furnace, twin-shell ladle furnace (LF) and a single vacuum oxygen degasser (VOD). EAF technical data: EAF type AC - SPOUT Heat size capacity 80 ton / 88 ston EAF diameter 5400 mm / 17.7 ft Transformer 60 MVA Charge 90% scrap + 10% pig-iron 2/3 buckets charge August 2011, a MORE Injection was installed on the EAF, which included: two M-One combined burner / supersonic oxygen / carbon injectors, one combined burner / lime injector, one Hi_JET combined burner / aluminum injector, two carbon dispensers, one lime dispenser, one aluminum dispenser, oxygen and natural gas valve trains, automation system and an intelligent Human Machine Interface to manage and supervise the melting process. M-ONE 2 x 1200 Nm 3 /h / 750 scfm (Supersonic/coherent oxygen injection mode) 2 x 3.5 MW (Mixed Swirl Flame burner mode) 2 x 12 kg/min / 28 lb/min (Carbon injection mode) LIME-JET 1 x 150 kg/min / 325 lb/min (Lime injection mode) 1 x 3.5 MW (Mixed Swirl Flame burner mode) HI-JET 1 x 30 kg/min / 65 lb/min (Aluminum injection mode) 1 x 350 Nm 3 /h / 220 scfm (Shrouding oxygen mode) 1 x 3.5 MW (Mixed Swirl Flame burner mode) WORK- SHOP The objective of MORE s quality policy is to guarantee the best levels of customer satisfaction, obtained by providing products with an excellent quality/price ratio. Equipment manufacturing and assembly is carried out in MORE s workshop where all phases are monitored very carefully by highly >>

4 In addition to the supply of the chemical energy package, a CATFIS automatic temperature and sampling manipulator was installed to measure bath temperature, carbon and oxygen content and take samples for chemical analysis without having to power-off the furnace. MODULE INSTALLATION LAY-OUT NATURAL GAS VALVE STAND OXYGEN VALVE STAND MOLI LIME MOCA CARBON MOCA CARBON MOCA ALUMINUM CATFIS << professionals skilled employees to achieve top-class quality standards. To both improve the reliability of our products and reduce the production costs, MORE has invested in state of the art CNC machining and turning centres. With this vertical level integration MORE produces 100% of the critical components in house, which will guarantee a high level of production and a quick delivery of spare parts.

5 NOVEMBER 2012 N 1 METALLURGICAL IMPROVEMENTS ALUMINUM INJECTION For the production of chromium alloy steel grades, during the melting and refining stages the HI_JET injector is used for the pneumatic aluminum injection into the slag/steel interface in order to recovery chromium from the slag as per the following chemical equation: Cr 2 O Al = Al 2 O Cr Theoretically, the chromium recovery is of 1,9 kg (4.2 lb) Cr for 1 kg (2.2 lb) of aluminum. Moreover, this chromium reduction is exothermic: adding 1 kg (2.2 lb) of aluminum generates a heat quantity of 2.9 kwh (1600 C / 2912 F). Parts of aluminum reacts with the oxygen becoming aluminum oxide (Al 2 O 3 ) which produces higher heat such as 8.7 kwh/kg Al (1600 C / 2912 F). Thus the aluminum injection has a double benefit: chromium recovery and additional exothermic energy input. Aluminum used for pneumatic injection is available from different sources: grains produced by metallurgical melting from primary Al or secondary Al grains treated mechanically (shredded) from scrap (cans, packing, etc). The use of secondary Al is cheaper. The lower quality of material does not influence the chromium recovery in the process. Grain size used for the slag injection is between 1 and 3 mm. The aluminum is injected at a flow rate of 30 kg/min (65 lb/min) during the refining stage, the average quantity of injected material is about 3,4 kg/t (6.7 lb/st) of liquid steel. OPERATIONAL RESULTS With the MODULE TECHNOLOGY there is a reduction of electrical energy and power on time and the foaming slag practice improves. Hence, higher production rates and substantial conversion cost savings per ton of liquid steel produced are achieved. Before Metric After Before Imperial After Heat Size (Liquid Steel) 80 t 80 t 88 st 88 st Electrical Energy 530 kwh/t 460 kwh/t 481 kwh/st 418 kwh/st Active Power 36 MW 38 MW 36 MW 38 MW Power on Time 115 min 85 min 115 min 85 min Electrodes 3.5 kg/t 2.8 kg/t 117 lb/ston 95 lb/ston Total Oxygen 10 Nm 3 /t 19 Nm 3 /t 337 scfm/st 642 scfm/st Total Natural Gas 1 Nm 3 /t 3 Nm 3 /t 33 scfm/st 100 scfm/st Charge Carbon Injected Carbon 10 kg/t 16 kg/t 20 lb/ston 32 lb/ston Total Carbon 10 kg/t 16 kg/t 20 lb/ston 32 lb/ston Total Lime/Dol. Blend 45 kg/t 45 kg/t 90 lb/ston 90 lb/ston Total Aluminum - 3 kg/t lb/ston Total Chrome Total Chrome Recovery 20 kg/t 50 kg/t 40 lb/ston 100 lb/ston Tapping Temperature 1730 C 1690 C 3146 F 3074 F

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