Introduction of CO2 Reduction Technologies in Steelworks - 陳俊達 博士

Introduction of CO2 Reduction Technologies in Steelworks - 陳俊達 博士

Transcript

1. 1 1 Introduction of CO2 Reduction Technologies in Steelworks Chun-Da Chen Energy Development and Application Section Green Energy & System Integration R&D Department China Steel Corporation (CSC), Kaohsiung Outline Relationship between Energy and Steelwork Reduce CO2 Emission during Energy Utilization Other Ways to Reduce CO2 Emission Concluding Remarks
2. 2 2 煤炭(coal) 鐵礦(iron ore) Limestone 助熔劑(flux) 1. Blast Furnace Steelmaking (BF Route) 2. Electric Arc Furnace Steelmaking(EAF Route) 廢鋼(scrap) DR Iron Flux 軋延 Rolling 鋼胚 Slab 電爐 EAF 煉焦爐Coke Oven 燒結機 Sinter 高爐 BF 煉鋼 BOF 軋延 rolling 最終產品 Final product 鐵水 (hot metal) 鋼胚 Slab Pellet Iron Ore Lump PCI Routes of Steelmaking 最終產品 Final product 2
3. 3 3 Energy System in BF Route  Input primary energy, producing secondary energy  Secondary energy flows among the processes in forms of Utility (steam, electricity, etc.)；  Production、Dispatch、Storage、and Utilization are key operational concerns. Coal Coke Oven BF BOF Rolling H.M coke COG BFG Upstream Downstream Slab Product LDG Heat Chemical Energy Gas Elec. Boundry of ISMP Combustion 載能體 90% 10% Electricity Furnace Utility Transform
4. 4 4 Energy Transformation in BF Route Input 還原 Reduction 熱能 39% Thermal Energy 電力 10% Elec. 電能 21% Electricity 化學能 40% Chemical Output Coal 煤炭 90% Process 耗電 Electricity Usage 加熱 Heating 4
5. 5 Byproduct Fuel in BF Route Fuel 燃料 H2 O2 N2 CO CO2 CH4 C2H 4 C2H 6 C3H 6 焦爐氣 (COG) 56.2 0.1 2.3 6.3 2.5 29.3 2.5 0.8 0.1 轉爐氣 (LDG) 1.1 0.1 13.9 70.9 14.1 高爐氣 (BFG) 3.9 0.0 52.2 22.5 21.4 Gas Theo. Air required (Nm3/Nm3) Theo. Flame Temp. (℃) Yield (Nm3/Year) Heating Value (kcal/Nm3) COG 4.2 2100~2130 1.995×109 4100 LDG 1.47 2000~2100 9.161×108 1674~1967 BFG 0.59 1200~1300 1.400×1010 781 5
6. 6 Approaches to reduce CO2 emission in BF Route 6  Reduce CO2 production in processes  Upgrade efficiency, equipment, etc.,  Process Innovation  Prevent emission to the atmosphere Two Major Approaches :
7. 7 7 WSA CO2 Breakthrough Program 7
8. 8 8 Time Schedule of CO2 Reduction Traget 0.0 0.5 1.0 1.5 2.0 2.5 2000 2020 2040 2060 2080 2100 BF-BOF Application 平均值(含EAF) Short Term Solution Improvement tonCO2 /tcs FullyImplement 0.9 0.8 8
9. 9 9 Reduce carbon emission during using energy
10. 10 10 Scopes to Lower GHG Emission in BF-Route Use low carbon energy Decoupling energy usage and CO2 emission Reduce end-of-pipe Emission Reduce energy usage Increase the energy conversion efficiency monitoring、dispatching、 automation、Intelligience Waste heat recovery CCSU Biomass/ Renewable energy Better combustion, enhanced heat transfer, more efficient system
11. 11 11 Energy Research Strategy Use of low carbon energy Decoupling CO2 usage and CO2 emission Enhance the end-of- pipe technology Emission reduction Increase the energy conversion efficiency Reduce energy usage monitoring、dispatching、 automation Waste heat recovery CCS Biomass Renewable energy Better combustion, enhanced heat transfer, more efficient system
12. 12 12 Installation of PV System  1.02 MWp PV system have been installed inside Hsiao-Kang plant.  CSC Solar was established in 2016, and will install 80 MWp on the 80 hectares roof area to generate 100 GWh power each year. 12
13. 13 13 Offshore Wind Power Development  China Steel Corp teamed up with the world’s major offshorw wind energy developer and inked a memorandum of understanding with Copenhagen Infrastructure Partners (CIP) and Diamond Generating Asia Ltd (DGA) , and plan to develop the No. 29 offshore wind energy concession zone obtained by CSC.  Total invest between NTD 80 and NTD 90 billion to install about 50 wind turbines in the water, which will have an annual capacity of 500 megawatts.  The formation of the alliance of the domestically produced offshore turbine components was completed. 13
14. 14 14 Application Route of Biomass
15. 15 15 Biomass pellet is an important source of renewable energy and plays a key role in circular economy of the fuel industry. Design features: Staging air combustion & Intelligent temperature control system Design and application of 5 Mwth wood pellet stove The relationship between the excess air ratios and the average temperatures of the main combustion chamber Grate firing stove with the design of staging air combustion y = 303.73x + 588.95 R² = 0.92 600 700 800 900 1000 1100 1200 1300 1400 0 0.5 1 1.5 2 2.5 Temperature(℃) Excess air ratio of the grate firing system Main combustion chamber
16. 16 16 Energy Research Strategy Use of low carbon energy Decoupling CO2 usage and CO2 emission Enhance the end-of- pipe technology Emission reduction Increase the energy conversion efficiency Reduce energy usage monitoring、dispatching、 automation Waste heat recovery CCS Biomass Renewable energy Better combustion, enhanced heat transfer, more efficient system
17. 17 17 1. Performance improvement and energy saving Energy Saving of Cooling Tower Action plan -To integrate, analysis and apply the process information of utility plants and coal chemical processes. Action plan - Improving efficiency of circulation fan and operation strategies for energy Compressor efficiency has been impoved 8.6%, CO2 is reduced 23.5 thousand tons per year. Unit consumption of indirect cooling water and fan power was reduced. CO2 reduction potential is 20 thousand tons per year. 廢熱回收強化 T Air,C CT 製程用水 T W,A T W,B Process Diagnosis and Optimal Operation  Applying Regenerative burner to Slab reheating furnace, Ladle Dryer, etc., and SOFC for generation.  Reducing CO2 emission, Saving fuel 25%, Reducing NOx emission 70%, increasing production rate 20% Regenerative burning system of Ladle Dryer Advanced Energy Utilization Technologies Water Solid Oxidixe Fuel Cell System
18. 18 18 5 1 0 1 5 2 0 2 5 3 0 8 8 8 9 9 0 9 1 D a ys O b s e rv a tio n s P L S F M W P L S O 2 Concentration (%) Inst rum ent Im proved Tradi t i onal X1 X2 . . . Xn Y Soft Sensor Modeling 1-1 Developing Soft Sensor Features:  Auto detect operation interval and self-update sensor’s model 18 Process Variables Key Variables (Predict)
19. 19 1-2 Diagnosis of Compressor Efficiency  Method:  Calculate and monitor compressor’s polytropic efficiency and intercooler’s thermal efficiency  Benefit:  Reduce the unexpected loss due to abnormal shutdown  Save energy consumption by 8.6% 2007/11/1 2007/11/8 2007/11/15 2007/11/22 2007/11/29 0.70 0.75 0.80 0.85 0.90 0.95 Polytropic Efficiency 1st Stage 2nd Stage 3rd Stage 4th Stage
20. 20 1-3 Modulation strategy of Compressor  Constant pressure control  The IGV will modulate the compressor inlet to maintain constant discharge pressure over the control range.  Compared to on-off control, constant pressure control can reduce unloading time and Save energy consumption by 3% 15.1% 14.0% 12.8% 11.2% 13.6% 12.7% 13.9% 2.6% 2.7% 0% 4% 8% 12% 16% Jan-17 Feb-17 Mar-17 Apr-17 May-17 Jun-17 Jul-17 7/21 ~ 7/31 Aug-17 排放比例(%) Unloading percent On-Off control Constant pressure control
21. 21 1-4 Decision Support for Oxygen Production Oxygen Vent Rate <2%、 Reduce Power Consumption>3% NO. 9 23189 11.45 22496 32.32 Air 230066 46031 Nm3/h NO. 8 34677 25.49 Air 187845 9 25.40 Air 0 NO. 7 GO2 NO. 6 NO. 5 Air Air LO2 1569 0 -50 Nm3/h 24.84 kg/cm2 134 Nm3/h 147 Nm3/h 104036 Nm3/h 4176 Nm3/h HP MP 高爐 23766 Nm3/h 0.21 2373 Nm3/h 132678 26.63 C40: C41: Nm3/h Nm3/h Nm3/h Nm3/h Nm3/h kg/cm2 kg/cm2 Nm3/h kg/cm2 Nm3/h Nm3/h kg/cm2 Nm3/h kg/cm2 kg/cm2 Nm3/h 3. Integrate Production and Storage Tank Level Information 2. Optimum Operation condition and Region 1. BF and BOF’s Oxygen Model (Demand) 21 BF1-4 BOF1-6
22. 22 Hot water Cold water •Fan system ─Improvement of fan ─Verification of high efficiency fan ─Adaptive VVVF system for Fan •Equipment ─Analysis of thermo mechanism ─Heat transfer enhancement ─development of fin structure •Intelligent monitoring system ─On line monitor system for cooling tower ─Smart diagnose system for motor ─Automatic warning and repair guiding system Diagnose •System integration ─Rationalization of using water ─Optima operation for cooling system ─VVVF pumping system Operation strategy 2. Energy saving strategy for cooling tower Performance enhancement
23. 23 23  Following the energy conservation law and CTI (Cooling Tower Institute) rule, We derermine the performance index of cooling tower. Performance index of cooling tower operation point performance index：(L/G) operation / (L/G) design operation point at design status
24. 24 24 On-line Monitoring System of CT performance information
25. 25 25  Utilized inverse engineering technology by using of the ATOS scanner to establish the 3D image of the blade, then applying the Imageware software to make it model smooth and editable.  The geometry of blade was imported to CFD solver and did series of numerical analysis. Simulation of Fan system
26. 26 26 26  Net power gain about 270kW and annual benefit 5 million NTD Optimal Operation with Turbine Net power generation efficiency can be improved by system-optimized operation mode
27. 27 27 3. Efficient Utilization of Fuel •Energy saving 25%，NOx reduction70%，throughput increased 20% 3-1 Regenerative Combustion System
28. 28 28 Examples of regenerative combustion system in CSC Ladle Dryer/Preheater Slab reheating furnace 鋁熔爐 2B 2A 1B 1A 燃燒器 進料門 稀釋空氣 廢氣Ⅰ 廢 氣 Ⅱ 廢 氣 Ⅲ 煙 囪 O2 測點 排氣風扇 天然氣 空氣 空氣 天然氣 Aluminum Melting Furnace
29. 29 29 More precise temperature control, less energy consumption. 3-2 Pulse Firing control Burner operates in ON/OFF mode. Load is modulated by ON time schedule of burners.
30. 30 30 Bell furnace with Pulse firing control Pulse control panel Examples of Pulse Firing Control Rod mill reheating furnace
31. 31 31 3-3 Oxyfuel Combustion Drastically reduce the emission as well as the waste heat increase the efficiency
32. 32 32 Oxyfuel ladle preheater in CSC Bright flame from oxyfuel burner Preheated ladle
33. 33 33 3-4 Enhance Radiation of Combustion W type U type Radiant Tube Combuster
34. 34 34 P-brand RTI unit testing (2015.08) P-、S-brands comparison (2015.11) Zone1 application testing (2015.12~) Application of Radiant Tube Inserts (RTI)
35. 35 (W/m2) Total heat flux Radiation heat flux Convection heat flux Convection heat flux Up surface 45,023 (larger) 22,603 22,392.4 (larger) 27.6 (larger) Down surface 38,355 23,990 (larger) 14,345.6 19.4 (Up /Down) 1.17 0.94 1.56 1.42 Boundary Conditions ： 1.Inlet ：Vin = 15 m/s；Tin = 1700 K 2.Oulet：gradient=0 3.Wall：Twall = 920 K Upper surface Bottom surface CFD Analysis of the RTI
36. 36 36 5 5.5 6 6.5 7 7.5 8 55 60 65 70 75 80 NG consumption(Nm3/ton) COG consumption(Nm3/ton) Unit consumption data Benefits of Using RTI -13.2 -37.7 -6.4 -35.3 -54.9 -9.7 -26.0 -51.0 -57.4 -92.7 -147.6 -157.3 -183.3 -200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 2016/01 2016/02 2016/03 2016/04 2016/05 2016/06 2016/07 Cost reduction (10 thsousands) 當月成本降低(萬) 累計成本降低(萬)
37. 37 37 3-5 Improving Reheating Furnace Efficiency 【Pressure Control】 【Real-Time Temperature Monitoring】 【Trend chart】 【3D temperature calculation】 【Oxygen Control】 【Process Monitoring & PreWarning】  Energy saving 12% (Energy consumption from 309 to 272Mcal/ton)
38. 38 38 3-6 Solid Oxidize Fuel Cell (SOFC) System (Stack) (IC) (Cell) (Sub-module) (Module) (System) Schematic system diagram Principle of SOFC
39. 39  Syngas concentration of COG reforming gas is up to 82.2%  COG is a high potential fuel applied on SOFC COG Inlet (%) COG- Reforming (%) NG- Reforming (%) CH4 28.3 2.2 0.5 H2 56.7 71 64.5 CO 6.7 11.2 10.8 CO2 3.3 7.4 N2 5 CO+H2 63.4 82.2 75.3 Coke oven gas (COG) Reforming COG & NG Reforming comparison Simulated COG Reforming for 170 hrs 39
40. 40 40 Energy Research Strategy Use of low carbon energy Decoupling CO2 usage and CO2 emission Enhance the end-of- pipe technology Emission reduction Increase the energy conversion efficiency Reduce energy usage monitoring、dispatching、 automation Waste heat recovery CCS Biomass Renewable energy Better combustion, enhanced heat transfer, more efficient system
41. 41 Major Waste Heat Source Waste Heat Source 2014.05 WHR (×109kcal/Y) Recovered (×109kcal/Y) Ratio(%) 1.Sinter Exhaust Gas 2,152 424 19.7 2.Boiler Flue Gas 1,940 1,212 62.5 3.Coke 1,396 698 50.0 4.Slab 1,039 256 24.7 5.Reheating Furnace Flue Gas 1,475 639 43.3 6.Hot Stove Flue Gas 671 371 55.2 7.LDG sensible heat 503 220 43.7(*1) 8.Low temperature waste heat 453 0.4 0.1(*2) Total 9,626 3,799 39.3 Note1: three sets of OG boiler has been installed and commissioning. Note2: heat recovery due to newly installation 2kW TEG system on reheating furnace.
42. 42  no commercial tech. available  hazardous environment  utilization restricted … Air Preheater TEG、ORC Waste heat source size large Cogeneration Waste Heat Boiler Waste heat temp. high Low efficiency Space constrained Intermittent … ? 650℃ 250℃ 1000℃ Slag SH (1800Gkcal/y) [~750Gkcal/y] CC Slab (1200Gkcal/y) [~200Gkcal/y] Raw COG (550Gkcal/y) [~200Gkcal/y] Waste Heat Recovery Regimes Focus on Low temperature and currently unrecovered high temperature waste heat
43. 43 Iron Ore Limestone COG BFG LDG O2 C.C. Slabs Reheating Furnace Annealing CGL/EGL Products Coil COG BOF Sinter Plant Cold Rolling Hot Stove Power Plant Torpeto car Hot Rolling Coal PCI TRT 高爐 高爐 BF HRSG HPHE System HRS burner CDQ System (3 sets of OG Boiler has been built) (Products include Billet, Plate, Wire Rod, Hot&Cold-Rolled Coil, Electrical Sheet…etc) CDQ CWQ Coking Plant Recuperator Major Heat Recovery System in CSC
44. 44 44 EPC for Recuperator of Reheating Furnace • A kind of gas-gas heat exchanger used to recovery waste heat • Categorized according to flow direction and unit number 2-pass 4-pass http://www.recuperatorindia.com/convection-recuperators.htm flue Combustion air stack damper Recuperator Flue duct Burner Discharge door Charge door Pre-heating zone Heating zone Soaking zone Slab Blower Combustion air Combustion air pipe Flue
45. 45 45 Technology Development • Temperature distribution analysis • Pressure loss analysis • Performance analysis of inserters • Recuperator performance analysis • Design technology (two passes and four passes types) Self-design and Manufacture of Recuperator
46. 46 46 Energy utilization Resources utilization Granulation Sensible heat recovery Heat extraction Direct solidification: CSIRO、POSCO..etc solidificationgranulation: JFE、PaulWurth Cold slag Hot slag Cold media 2 steps Hot media Recovery of Slag Sensible Heat
47. 47 47 Dry granulation Rotary Rollers Steel ball POSCO CSIRO…etc JFE PaulWurth Heat exchange Hot water Hot air Direct heat exchange Heat utilization Chemical conversion Gas reforming Coal gasification Biomass pyrolysis Direct utilization Process heating Power generation Slag heat recovery techniques breakup
48. 48 48 •The final slag utilization dominates the selection of dry granulation method •Dry granulation method rules the selection of heat exchange system •Slag heat recovery technology is still under development.
49. 49 49 Evaporator G Condenser Cooling system Turbine Waste heat stream Water inlet Water outlet Working fluid stream ORC SYSTEM (Organic Rankine Cycle System) 1 2 3 4 Pump Evaporator G Condenser Cooling system Turbine Waste heat stream Water inlet Water outlet Working fluid stream ORC SYSTEM (Organic Rankine Cycle System) 1 2 3 4 Pump Electricity from TEG Electricity from ORC by waste heat Low temp heat recovery – TEG、ORC
50. 50 50 What is “Thermoelectric generation” (TEG)? Solid-state energy conversion between thermal energy and electricity SAB = SA -SB = (DV/DT)Je=0 V T+T A B A T  Seebeck effect (thermal energy → electrical energy) Thermoelectric Generation (TEG)
51. 51 Strength for TEG technology development in CSC Advantages of TEG technology Strength for TEG technology development  Industrial uniqueness：large amount of waste heat sources  Extension of existed core technologies：technologies of material, melting, and heat transfer analysis  No moving part, small volume, no noise, low maintain cost  High flexibility, little constraints of space and economic scale, suitable for intermittent waste heat sources。
52. 52 Re-heating Furnace Wall Tests of TEG Systems in CSC •Heat lost from furnace wall was recovered then generated by attaching TEG modules. •First kW-level furnace wall TEG system in the world was completed. •Heat lost from furnace wall was recovered then generated by attaching TEG modules. •First kW-level furnace wall TEG system in the world was completed. Top view Bottom view Location •Unique flow deflector design increases heat-collection performance, installation density, and system protection. •Max. output power reaches 2.4kW. •Unique flow deflector design increases heat-collection performance, installation density, and system protection. •Max. output power reaches 2.4kW. #4/#5 CC TEG system #6 CC TEG system •Effective heat generation system was designed and installed to recover waste heat of high temperature solid. •Effective heat generation system was designed and installed to recover waste heat of high temperature solid. Deflector Boiler Flue Duct Continuous Casting Slab
53. 53 53 6kW TEG System for CC slab TEG system un #6 SCC Display Panel Test system Effect on generation of operation parameters(slab temp., system height and surface condition, etc.)
54. 54 expander condenser inlet outlet inlet outlet evaporator generator Organic Rankine Cycle (ORC) Working fluid with low boiling point (e.g. refrigerant) operates in Rankine cycle to convert low-temperature heat to power. pump condenser evaporator Expander and generator Heat source pump Cooling water
55. 55 55 • Integrating 200kW ORC and Recuperator to make sure the exit temperature of flue gas under the emission standard, and recovered heat as large as possible. Combustion air Flue gas Reheating Furnace ORC Combustion air required Surplus combustion air Exit temp. <460 ℃ Hybrid Recovery System • Operation capacity 140~155kW，electricity output 96,000kWh/month。
56. 56 56 Other ways to Reduce Carbon Emission
57. 57 57 1. District Energy/Resource Integration
58. 58 58 Synergy： 1. Decrease fuel usage and waste heat, reduce SOX 、NOX emission. 2. Decrease total CO2 emission in the area. Illustration of Energy Integration
59. 59 59 Energy/Resource Integration in LinHai Industrial Park  Utilization of surplus steam, oxygen, nitrogen, argon, compressed air from steel mill and so on to the nearby plants within industrial district.
60. 60 60 Benefit of Energy/Resource Integartion (Example by steam sale)  From 1994 to 2018， the accumulated benefit in Air Pollution and GHG Emission Redution is Energy saving ：2.23Million KL equvilent fuel oil SOx ：20.0 Million kg NOx ：15.0 Million kg PM： 2.0 Million kg CO 2 : 4,640 Million kg  Received Benchmark Award of energy/resource integration of Industrial Development Bureau and Best Industry Award of Energy Saving of Bureau of Energy.
61. 61 61 Oxy-Fuel Combustion CO2 Capture CO2 Utilization Carbon capture and Utilization  A 300kW Oxyfuel combustion with FGR pilot plant.  Tests of heavy oil/natural gas oxyfuel combustion.  A microalgae carbon fixation technology  Evaluation of BOF slag on capturing CO2 and carbonation .  Establishing a 100 kg/D chemical absorption carbon capture pilot plant.  NH3 and amine-based solvents were studied. 2. Carbon capture and Utilization
62. 62 62 A Novel NH3-based Capture Process • Overcome the defects of Escape low temperature washing and expensive deep regeneration in traditional NH3 process • Staged absorption and tail gas cleaning derived from experience of our Coal Chemical Plant, having proved its availability by pilot tests Modified CO2 absorber with staged- absorption concept Two stage tail gas cleaning
63. 63 63 Replace cement by ground water quenched BF slag can save electricity 40kWh, decrease required limestone 1.2ton, reduceCO2 emission0.79ton per ton slag. Resourcing of BF slag
64. 64 64 Carbon Utilization by Mineralization (CUM)  Industrial residues such as BOFS (Basic Oxygen Furnace Slag) are alkaline: - CaO, MgO, SiO2 , Al2 O3 , Cr2 O3 , TiO2 , MnO, iron oxides  Advantages of Carbonation using Alkaline Wastes - Thermodynamically stable, Exothermic reaction (limits the costs) - High available deposits, Don’t require transport (cost - effective) - Reused in construction materials, Improve environ. quality (decrease heavy metal leaching)
65. 65 65 High-gravity Carbonation Process - RPB Serial tests of RPB apparatus
66. 66 66 Potential Application of CUM Steel Work Slag Size <5 mm Plant CO2 capture Water addition (CaO)slag +CO2 in Plant Exhaust via Water Film = CaCO3 Marine Block CO2 Sequestration Slag Layer Carbonation Reactor Exhaust Fix CO2 in Slag
67. 67 67 The steelworks processes are close related with fossil fuel and CO2 emission. Best Available Technologies are widely used in the steelworks for saving energy and reducing CO2 emission. Many R&D activities are moving the steelworks toward a cleaner, more efficient and less emission future. Concluding Remarks
68. 68 68 Thank you for your attention. Wellcome Feedbacks Chun-Da Chen E-mail：122390@mail.csc.com.tw Tel：886-7-8021111ext.2844