i Steel®: Tenova Innovative Technologies: How to Reduce Production Costs and Environmental Impact MMMM 2012 – Resurgent India: Vision 2020 in Metals & Minerals Sector New Delhi, September 29th , 2012 Davide Masoero Area Manager i Steel Melt Shops Tenova S.p.A. Iron&Steel Division Vision 2020 Drivers to face the challenge of the next decades: Flexibility Environment friendliness Continuous data collection Real time process analysis Dynamic control Are we ready? YES Tenova i Steel Technologies 2 i Steel® - Tenova Innovative Technologies The philosophy Increase steel making process efficiency • Exploit energy input inside EAF i EAFTM Dynamic process control system through real-time measurements • Recover wasted energy exiting EAF i Recovery® Steam production through offgas energy recovery The i EAF® The i EAFTM 4 i EAF® - Definition i EAF® Technology is a modular program that provides savings and productivity improvements by optimizing and dynamically controlling the EAF process. It is a system for dynamic, real-time control and optimization of the electric arc furnace that uses sensors, models and real time advanced control algorithms. Module 1 – EFSOP® System Description Patented Probe Patented water-cooled probe continuously samples the off-gas exhaust for the Goodfellow EFSOP™ gas analyzer Gas Analyzer Measures levels of O2, CO, CO2 and H2 and sends the data to the operator screens and to the Goodfellow EFSOP™ computer in the furnace control pulpit EFSOP™ HMI & SCADA . Plant PLC Plant PLC network communicates with the EFSOP™ analyzer and computer to receive new setpoints for dynamic furnace control Goodfellow EFSOP™ computer (closed loop control) and/or operator send process adjustments to the plant PLC network 6 Module 1 – Off-Gas Losses Unburnt chemical energy (CO and H2). Up to 70% of chemical energy added is wasted. Ideally, these gases are combusted mostly in the furnace to help lower kWh. In poorly balanced furnaces, a portion of these gases are combusted even further downstream leading to higher temperatures in the fume system. In severe cases, baghouse fires and explosions occur. C h e m ic a l O ff-G a s H e a t L o a d 40 S e n s ib le O ff-G a s H e a t L o a d 35 30 25 20 15 10 5 0 T im e (M in u te s in to h e a t) 40 35 30 25 20 15 10 5 0 Time (Minutes into heat) 7 Module 1 – EFSOP® Off-Gas Chemistry EFSOP® measures CO, O2, CO2 and H2 continuously at the fourth-hole. 8 Module 1 – Chemical dynamic control Closed loop control based on offgas composition Module 1 – Proven EFSOP® Economic Savings MacSteel ** Deacero ** Customer Verified Savings Nucor Auburn For installations allowing public disclosure. Savings based on: Nucor Seattle Hylsa Electricity Fuels Charge & Injected Carbon Oxygen Yield ** Productivity ** Cape Gate Thamesteel POSCO Topy CMC-AL Dongkuk $0,00 $1,00 $2,00 $3,00 $4,00 $5,00 Customer Verfied EFSOP® Savings US$ per tgb 10 Module 2 – i EAFTM New Advanced Sensors Sensors: EFSOP Off gas composition Off gas flow sensor Off gas temperature sensor Off gas pressure sensor Measurements: CO, CO2, H2, O2, H2O* Temperature Flow Pressure * under testing Module 2 – i EAF® advanced process models Advanced sensors information cooling water circuit information chemical electrical real time data plant bucket information Off gas, cooling panels, furnace bottom losses Net bath oxidation and decarburization Oxidation energy Net energy transferred to charge Melting progress The MP defines the progress of the heat. It is the ratio between the liquid formed over the total amount of charged material. MP = (Net energy to charge)/(specific energy required to melt * charge weight) Module 2 – MP control innovation Electrical and Chemical closed loop control based on MP Module 2 – Installations and Results 6 M2 i EAFTM installation 4 M2 i EAFTM underwork: TenarisDalmine Riva Verona (2 EAFs) ArcelorMittal Dofasco (2EAFs) Beltrame Vicenza Tenaris Tamsa (Summer 2012) Ternium Siderca (Summ. 2012) – i DRI® Ternium Puebla (Summ. 2012) – i DRI® Sidor (December 2012) – i DRI® Plant 1 Plant 2 (2EAFs) Plant 3 (2EAFs) Electrical Energy kWh/tgb - 2,30% - 2,50% - 3% ÷ - 5% Fuel (CH4) Nm3/tgb - 3,70% - 16,3% - 5% ÷ 0% Oxygen (O2) Nm3/tgb - 0,20% + 0,30% - 1% ÷ - 1% Productivity tgb/h + 2,40% + 5,20% In addition to the EFSOP Savings Module 3 – T&C prediction Once MP =100%, the Bath & Slag model will use the calculated specific net energy, to evaluate in real time the bath temperature and composition behavior. The predicted temperature is the average bath temperature. It has to be carefully compared with the local immersion thermocouple measurement. The predicted carbon is statistically corrected to the errors in the carbon in and out evaluations. In addition it is corrected once the first ppm reading is taken. Module 3 – Temperature prediction Temperature error std deviation: 24.9 Celsius. The i Temp® i Temp® - Tenova Patent EP1440298-B1 Patented technology for optical measurement of the temperature of the liquid steel Optic pyrometer installed on a KT lance Easy equipment integration FOV through the main oxygen Nitrogen supersonic injection for slag surface opening 18 Pyrometer signal during nitrogen shoot Average spectral radiance ratio during the nitrogen shoot 0.55 The nitrogen shoot opens the slag surface, the signal decreases because molten steel is colder than slag 0.45 0.4 0.35 0.3 0.25 0.2 0.37 0.15 0 2 4 6 8 10 12 Refining time (min) Nitrogen shoot cycle takes 1sec Nitrogen introduced in the EAF is 0.577Nm3 14 0.32 Spectral radiance ratio, N1/N2 Spectral radiance ratio, N1/N2 0.5 0.27 0.22 0.17 0.12 Shooting time 1sec 0.07 0.02 8.18 8.2 8.22 8.24 8.26 8.28 8.3 Refining time (min) 19 i Temp® Vs Immersion thermocouple Immersion Thermocouple iTemp 1800 1750 Temp (°C) 1700 1650 1600 1550 1500 1450 300 310 320 330 340 350 360 370 380 EE (kWh/ton) 20 TAT® - Tenova Auto Tapping TAT® - Tenova Auto Tapping Automatic Tapping TAT® - Tenova Auto Tapping Automatic EBT refilling TAT® - Tenova Auto Tapping Robot for EBT Cleaning TAT® - Tenova Auto Tapping Lance for EBT Opening The i RecoveryTM 26 i RecoveryTM - Description 100 t/h EAF from 14 t/h to 28 t/h steam produced 20 – 25 % of primary energy can be recovered 27 i Steel technologies - Installations Davide Masoero [email protected]