Influence of metallics and EAF type on specific consumptions and productivity
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The document examines the influence of metallics and electric arc furnace (EAF) type on power consumption and productivity, utilizing a global survey of EAFs and their operational data. It identifies distinct power consumption ranges associated with different metallic charges, highlighting the impact of charge composition on efficiency and productivity. The conclusions emphasize the importance of scrap preheating and the efficiency variances between different EAF designs.
Influence of metallics and EAF type on specific consumptions and productivity
- 1. Influence of metallics and EAF type on specific consumptions and productivity Jorge Madias (1), Andrea Bilancieri (2), Sara Hornby (3) (1) metallon, San Nicolas, Argentina (2) TenarisSiderca, Campana, Argentina (3) Global Strategic Solutions, Inc., Charlotte, North Carolina
- 2. Content Introduction Survey Power consumption Other factors Oxygen consumption Eletrodes Productivity Conclusions
- 3. Introduction metallon Consulting & training company based in San Nicolas, Argentina TenarisSiderca Seamless pipe producer located in Campana, Argentina DRI plant, EAFs, LFs, Round billet/bloom casters Global Strategic Solutions Consulting company based in Charlotte, SC, USA
- 4. Introduction Large variation in scrap quality and alternative iron sources and utilization, depending on country /region Variety of furnace designs available A look at influence of metallics and EAF design on specific consumptions and productivity Based on survey of published figures of EAFs around the world Data base from public sources 2010 - Feb 2017 Not included EAFs for steel castings, forgings and steel powder EAFs producing exclusively stainless and tool steels EAFs with heat capacity lower than 30 t 190 furnaces worldwide
- 5. Introduction Charge types include 100% scrap Up to 40% pig iron Up to 60% hot metal Up to 100% DRI/HBI Up to 100% hot DRI Products Merchant long products SBQ Flat products (coil and plate) Seamless pipes
- 6. Introduction Transformer power vs. Heat capacity
- 7. Survey Specific consumption in terms of metric tons of liquid steel in the ladle Data included Company / group; plant name; country EAF type, heat capacity; transformer power; electrode diameter Productivity; tap to tap time; power on time Power; oxygen; injected carbon; natural gas; electrodes consumption Metallic yield; charge type; product type; reference Published data corresponds usually to a specific operation period Consumption figures and productivity times change depending on demand and other situations that may vary over time
- 8. Power consumption Depends upon metallics, and their thermal state at charging <300 kWh/t Nine of the top ten: nine charge >20% hot metal Energy consumed in the blast furnace EAF CO2 emissions larger than usual 300 – 400 kWh/t Best scrap-based EAFs Charge of >20% pig iron 400 – 450 kWh/t Intermediate scrap-based EAFs Charge of >90% hot DRI >450 kWh/t Worst scrap-based EAFs Charge of >50% cold DRI/HBI
- 9. Power consumption Influence of metallics and their thermal state
- 10. Power consumption Country Heat cap. (t) Current Type Transformer (MVA) TtT (min) Power cons. (kWh/tls) O2 (Nm3/tls) Metallics other than scrap (%) Product China 50 AC Standard 67 132 54 HM LS China 100 DC Standard 90 44 177 47 57.5 HM LS China 110 AC Standard 80 33 220 33 30 HM LS Russia 175 AC Standard 150 45 223 34 22 HM LC Taiwan 155 AC Twin Shell 120 44 225 37 35 HM LC China 110 AC Standard 80 35 240 33 30 HM SP China 110 AC Standard 80 35 240 33 30 HM SP Brazil 110 AC Standard 48 43 265 30 HM LC Brazil 80 AC Standard 75 295 31 25 HM/5PI LC Singapore 80 AC Shaft 48 295 0 LC Turkey 195 AC Standard 47 300 38,5 0 LC South Afr. 170 AC Conarc 115 57,5 310 43 50 HM/ 50 cDRI FC India 180 AC Conarc 137 57,5 310 50 HM/50 cDRI FC Korea 120 AC Shaft 49 314 31 not known LC Vietnam 63 AC Consteel 33 54 328 10 HM LC Mexico 110 AC Standard 85 90 330 7 cDRI LC Italy 95 AC Standard 100 42 340 20 10 PI SP Brazil 50 AC Standard 36 343 60 30 PI LC Brazil 50 AC Standard 48 343 60 30 PI LC Mexico 56 AC Standard 55 55 345 7 cDRI LC
- 11. Power consumption Influence of furnace type Only EAFs charging >80% scrap
- 13. Oxygen consumption Advances in chemical energy utilization, through high capacity injectors Influence of metallics >20% hot metal: 36.3 Nm3/t >20% pig iron: 43.3 Nm3/t >20% DRI/HBI: 31.7 Nm3/t >80% scrap: 31.7 Nm3/t
- 14. Electrodes Many furnaces using 610 mm electrodes, tapping 70 to 200 t per heat DC furnaces (1 or 2 electrodes) present the larger diameter, for a given heat capacity
- 15. Electrodes Electrode consumption vs. power consumption
- 16. Hourly productivity Linked to furnace size EAF feeding slab casters are the more productive
- 17. Power-on time Top 20 EAFs have a varied heat size (35 to 220 t) 17 of them dedicated to merchant long products EAFs linked to billet casters equipped with metering nozzle and oil lubrication Higher casting speed Longer sequences
- 18. Power-on time Country Heat cap. (t) Cur. Type Transformer (MVA) TtT (min) Power on (min) Power cons. (kWh/tls) O2 (Nm3/tls) Other than scrap Prod. Spain 130 AC Standard 140 43 29 SC Long C Germany 100 AC Standard 90 41 30 365 38,6 SC Long C Germany 100 AC Standard 90 41 30 365 38,6 SC Long C Belgium 90 DC Standard 99 42 31 370 44 SC Long C Russia 175 AC Standard 150 45 32 223 34 HM Long C USA 35 AC Consteel 30 55 32 350 31 SC Long C USA 171 AC Shaft/Twin 140 38 32 372 50 PI Flat C Brazil 110 AC Standard 48 43 33 265 HM Long C Norway 89 AC Consteel 75 41 33 384 26 SC Long C Turkey 220 AC Standard 230 41 35 360 35 SC Long C USA 154 DC Standard 180 40 35 386 41 CDRI Flat C USA 154 DC Standard 180 45 35 386 41 CDRI Flat C Luxemburg 160 DC Twin Shell 35 SC Long C China 100 DC Standard 90 44 36 177 47 HM SBQ Brazil 80 AC Standard 75 37 295 31 HM Long C Korea 100 AC Standard 100 45 37 354 29 SC Long C France 92 DC Standard 72 54 37 375 44 SC Long C UAE 152 AC Standard 130 64 37 392 35 HDRI Long C Belarus 110 AC Standard 95 38 386 SC Long C Qatar 85 AC Standard 78 50 38 480 35 CDRI Long C
- 19. Conclusions There are four ranges of power consumption associated with the metallic charge <300 kWh/t for EAFs charging more than 20% hot metal 300 - 400 kWh/t for the more efficient scrap-based EAFs and those charging more than 20% pig iron 400 - 450 kWh/t for intermediate efficiency scrap-based EAFs, and those charging hot DRI >450 kWh/t for low efficiency scrap-based EAFs and those high quantities of cold DRI/HBI Favorable influence of scrap preheating, with transporter, shaft or twin shell DC EAFs do not differ much on power consumption, but are in the lower range of electrode consumption
- 20. Jorge Madias (1), Andrea Bilancieri (2), Sara Hornby (3) (1) metallon, San Nicolas, Argentina (2) TenarisSiderca, Campana, Argentina (3) Global Strategic Solutions, Charlotte, NC, USA