Innovations in Iron and Steel at JSW Steel Ltd

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1 Innovations in Iron and Steel at JSW Steel Ltd

2 Background Incoming iron ore fines of JSW are of wide variation in physical and chemical properties. The higher gangue content (Al2O3+SiO2) and the ultra fines (<150 micron) are detrimental to agglomeration process. Low grade iron ore fines beneficiation to get the consistency w.r.t physical & chemical properties of iron ore fines after mining ban at Karnataka. Usage of high manganese iron ore fines at Agglomeration and its impact in steel making. Blast furnace performance with respect to 90 percent agglomerate burden. Waste handling through micro pellet plant for efficient utilization in base mix. Usage of recovered slime through slime recovery plant in pellet making.

3 Source wise Iron Ore Chemistry-Low & Medium Grade Low Grade IOF Medium Grade IOF Wide variation in Chemistry

4 Jig and Spiral Performance Particle size distribution Jigs & Spirals feed Jigs & Spirals Conc. Medium (+1)mm grade IOF (-150) mic Low grade (+1)mm IOF (-150) mic Medium grade IOF Low grade IOF Jigs & Spirals feed Jigs & Spirals Conc. % up-gradation Jigs & Spirals feed Jigs & Spirals Conc. % up-gradation Fe(T) SiO Al2O LOI _ Improved up-gradation in case of low grade IOF with respect SiO2 and Al2O3

5 Product Distribution of Low and Medium Grade IOF

6 Comparative Analysis- Low and Medium Grade IOF Low Grade Medium Grade Feed Fe Feed SiO Feed Al2O Sinter Product Fe Sinter Product SiO Sinter Product Al2O Pellet Product Fe Pellet Product SiO Pellet Product Al2O Tails Fe Improved Product grade up-gradation in case of Medium Grade Processing Comparable product grade up-gradation of sinter fines in both cases

7 Raw Material Challenges in Agglomeration Bellary and Hospet Iron ore fines are soft and flaky in nature with high content of Al2O3 and SiO2 High Super fines (<100 mesh) percentage Low Tumbler and flaky nature of local lump ore is detrimental to high productive BF. To minimize the lump ore dependency, about 90 % of BF burden as agglomerate

8 Impact of Calcined Lime addition in Sinter Making Sinter productivity improves with ground Calcined lime addition (<75 micron) due to better Quasi particle strength and Granulation of sinter green mix.

9 Sinter Chemistry Management at JSW Usage of 10 to 15 percent beneficiated sinter product in base mix preparation, lower the gangue content and minimizes the ill effect of ultra fines (<100 mesh %) Usage of imported limestone and dolomite reduces the gangue content in sinter and Alkali Input to BF Usage of Anthracite coal as a solid fuel reduces the VM (<4, %) Usage of High Manganese iron ore fines in base mix blend which contain low alumina, reduces alumina in sinter

10 Anthracite Coal addition VS Solid Fuel VM ESP performance improves with reduced VM in solid fuel after blending with Anthracite

11 Impact of High MnO IOF Usage in Sintering High MnO IOF reduces the sinter alumina from 5.23 % to 4.85 % Low alumina sinter reduces the BF slag rate from 571 Kg/thm to 544 kg/thm High MnO percent in sinter along with high alumina reduces the sinter Tumbler by Index by 2.09 percent

12 Impact of Secondary Nodulizer in Sinter Making Improved Granulation during secondary Nodulizer operation leads to High Productivity with low Fan RPM Lower Fan RPM helps in reducing the power consumption Improved BTP help in achieving better sinter quality w.r.to Tumbler Index and MPS

13 Impact of Green Mix Carbon Percentage on Pellet Making Green Mix Carbon% ranges Green Mix carbon,% CCS Tumbler Index Abrasion Index RDI RDI (+6.3mm)% (0.5mm)% (6.3mm)% (0.5mm)% Unfired % > to 1.15 percent green mix carbon is optimum for better pellet properties

14 Impact of < 45 micron Grain Size on Pellet Properties Pellet Properties Unit Increase in (<45) mic,% in Pellet Concentrate <55% 55-60% 60-65% 65-70% >70% AI (-0.5mm) % TI (+6.3mm) % CCS Kg/pellet RDI (-6.3mm) % RDI (-0.5mm) % RDI (-3.15mm) % Pellet Properties significantly improves w.r.to CCS, TI and RDI with increase of <45 micron percentage in pellet concentrate

15 Unit Process Calcination plant Refractories plant Sinter plant Coke Ovens Pellet plant Blast furnaces Corex Waste Material in Integrated Steel Plant H M desulphurisation BOF steelmaking Secondary steelmaking By-product Lime fines, semi-calcined lime, lime stone undersize Refractories waste Electro-filter dust, air borne dust Coke breeze, coke oven gas Pelletization slurry B F gas, top gas dust & sludge, cast house & bunker house dedusting, and slag granulate Corex sludge, slag Slag, dust L D gas, slag, sludge, primary & secondary dedusting dust, vessel slopping Slag, dust Rolling mill Mill scale Recycling of waste material is best method to protect Environment which leads to cost reduction also

16 Waste Recycling Management at JSW Three Major initiatives developed to utilize waste generation Micro Pelletizing Plant Slime Recovery Plant Briquetting Plant It process all dry waste like Bag Filter dust, LCP dust etc in desired proportion to meet the base mix quality requirement It process old dumped tailing from tailing pond to get desired product for pellet making. Mill scale Briquetting Reduction Specific IOF and flux consumption at sinter plant Low sinter cost Input % Fe upgrade to % Fe Low pellet cost It is used in SMS as Coolant Low steel cost

17 Impact of Micro Pelletisation on Waste Consumption Before Micro Pellet After Micro Pellet Metallurgical Waste Consumption increased from 50 kg/tons to 70 kg/tons

18 Major Innovative Initiative at Coke Oven 1) Usage of petroleum coke as an additives in coal blend to produce desired quality metallurgical coke a) It helps in decreasing the coke ash by 17 percent and subsequently BF coke rate to the extent of 14kg/thm 2) Installation of Coke Dry Quenching system-following advantage are depicted below a) Conserve heat energy and water resources b) Water pollution minimization in compare to Conventional quenching method c) Reduction In CO emission. d) Power Generation e) Significant reduction in solid fuel consumption at Iron Making due to coke reduced and consistent moisture compare to conventional method

19 Impact of Coke Moisture on BF Fuel Rate Significant reduction in fuel rate in BF with reduced sp. Moisture input through coke

20 Technical Specification-Iron Making Parameters Units CX#1 CX#2 BF#1 BF#2 BF#3 BF#4 Date of Blow in 8th Aug Apr Aug Aug-06 18th Feb-09 18th July-11 Production Capacity Mtpa Avg. Production tpd Productivity (WV) t/m 3 /day Working Volume m Inner Volume m No of Tuyeres no Hearth Diameter m Tap holes no Hot Blast Temperature o C NA NA Stoves no. NA NA TRT Station MWh NA NA NA NA

21 Milestones of JSW Iron Making

22 Impact of Sinter Burden on BF Productivity Significant improvement in BF productivity after Increased sinter percentage in Burden from 50 to 80 %

23 Impact of Productivity on BF Fuel Rate Reduction in Fuel rate after improved productivity with increase of sinter percentage in BF Burden

24 Impact of Tap Duration/day and Slag Ratio Improved Casting Practices through optimization of Tap Hole Diameter, Slag Ratio and Cast Duration through in-house developed Casting Model and Slag-Balance Model

25 High Slag Rate Management at BF Increased slag rate from 380 Kg/thm to Kg/thm due to increased sp. Alumina from from 55 Kg/thm to Kg/thm Following Methodologies were adopted to optimize the process with high Slag rate operation at BF3 & BF4 Optimizing Sinter Chemistry to minimize Raw Flux addition at Blast Furnace Optimizing Slag Chemistry: Al2O3-19.5% max., MgO 7.5 to 8.0%, B Stabilizing Burden descent by taking corrective and preventive measures to control Channeling and Irregular Burden Descent. Optimizing Burden Distribution and blowing parameters to take care of Flooding & Loading of slag in lower part of the furnace

26 Impact of Sp. Alumina and Slag Rate on Productivity Sustained Productivity during high slag rate

27 Innovation in Corex Units Optimization of Fix-Carbon/thm from 670 to 600 kg/thm through reduction in Sp. Oxygen from 560 to 510 Nm3/thm Lump Coke replaced by Nut Coke in Corex with sustainable furnace stability resulting in low hot metal cost. Reduction in Fuel Rates by introduction of additional Coal Drying facility. Enhancement of Melting Rate through usage of Sinter fines directly into the Melter Gasifier to negate the limitations in Reduction Shaft. Control of tuyere burning by optimizing the Slag Chemistry

28 Optimization of Carbon rate and O2 Consumption in Corex

29 HMPT at JSW Vijayanagar Works In the present time most of the iron making units is characterized by high silicon and phosphorous, due to poor raw material characteristics. Removal of these impurities increases the processing time at LD converter and ladle treatment and No full scale hot metal pre-treatment have been proved economically successful. JSW Steel, Vijayanagar Works, has successfully introduced India s first Hot Metal Pre-Treatment (HMPT) facility. JSW envisaged the removal of silicon and phosphorous separately by injection of reagents, fluxes and oxygen through two lances in the transfer ladle in a two step process.

30 HMPT at JSW Vijayanagar Works De-Si and De-P De-S Blast Furnace 2 Blast Furnace 1 COREX 2 COREX 1 De-Si De-P De-S De-C

31 Composition Change 1 st Stage De-Siliconisation 2 nd Stage De-Siliconisation De-Phosphorisation Silicon Wt % Average Si = 0.8 % Average P = 0 % Silicon Wt% Start End Start End Start End Average Si = 0.4 % Average P = 0 % Phosphorous, Wt % Average Si = 0.2 % Average P = 0.06 % The acceptable level of drop in silicon and phosphorous levels have been optimized to keep the treatment time minimum without affecting the temperature. These levels have helped in keeping the charged hot metal average silicon and phosphorous levels lower and consistent to primary steel making.

32 Benefits of Pre-Treatment Reduction in converter tap to tap time Improvement in Steel Cleanliness Reduction in slag generation and increased recycling

33 Slag Splashing

34 Slag Splashing Slag splashing is a process slag on the refractory lining of the vessel of coating of left over It cools, solidifies, and creates a solid layer of slag that serves as a consumable refractory layer. Initial Refractory Thickness : 900 mm

35 Process Optimization Tap Temperature Slag Height Initial Lance Ht Slag Characteristics Splashing Pattern Time of Splashing

36 Innovations Slag Mushrooming Selective Splashing To increase the life of bottom plugs To splash the areas of localized erosion

37 Results Structured methodologies has been successfully used to improve the converter lining life. Slag conducive for effective coating is developed. Splashing parameters have been optimized. Innovative methods of slag mushrooming and selective splashing have been initiated. Furnace availability has increased. Holds the national bench mark of heats

38 LD Slag Granulation

39 LD Slag The use of blast furnace slag as a constituent of concrete, either as an aggregate or as a cementing material, or both, is well known. LD slag due to its very non-uniform nature and metallic content it was never successfully utilized in cement making. In recent years, processed steel slag has evolved as an alternative construction aggregate for many specialized applications.

40 Iron & Steel Slag : Comparison BF Slag Steel Slag Limestone is chemically converted in high temperature processes(high CaO). Generation@350kgs/tcs CaO 33%;SiO2 30%;FeO 0.3% LowFreeLimeContent Low iron oxide fraction Negligible metallic iron fraction Better hydraulic properties Granulated and used in Cement making Limestone is chemically converted in high temperature processes(high CaO). Generation@200kgs/tcs CaO 45%;SiO2 12%;FeO 20% HighFreeLimeContent High iron oxide fraction High metallic iron fraction Poorer hydraulic properties Metallic part recycled; rest is dumped

41 LD Slag Granulation JSW Steel introduced India s first LD Slag Granulation process for increasing the re-cycling of LD Slag LD Slag Granulation involves sudden quenching, of the molten slag, leading to different contraction of metal and slag and results in good separation of metal and slag. Adequate granulation takes place and leads to good stability of the final slag. Process can be called as accelerated ageing process which reduces the free lime content. Removal of free lime also confirms its volumetric stability. Because of rapid cooling it generates more glassy structure than the air cooled slag.

42 LD Slag Granulation Shape of the granulated slag sand is similar to BF Slag. Microscopically also, BF and LD slags are similar.

43 Use of Granulated LD Slag With the introduction of LD slag granulation, new avenues of its applications have been identified through in-house trials and in collaboration with NCCBM (National Council for Cement and Building Research). Extensive studies have been carried out at JSW confirmed following applications. As Raw Material in Cement Manufacture (up to 4.25 %) As Performance Improver in cement making (up to 5 %) As Blending Materials in cement making (up to 40 %) As Replacement of Natural Sand in Cement Mortar (up to 100 %)

44 Utilization of Mill Scale Briquettes

45 Mill Scale Briquettes All Integrated steel plants generate waste oxides such as mill scale, caster scale, CRM dust, sludge, dust etc. There is also environmental pressure to adopt eco-friendly strategies to reduce, recycle and re-use their wastes. One way is through improvements in technology, operational practices, or adopt/develop clean processes, or processes that do not generate the same amount of waste. Requires huge investments and large design changes. Present industrial focus is to convert the generated wastes to usable form and re-cycle back in the present process route.

46 Mill Scale Briquettes JSW steel is the first plant in the country and one of the very few in the world to adopt mill scale briquetting. Mill scale, caster scale, CRM dust and similar high iron containing wastes are mixed and briquetted. Presently mill scale briquettes are being used in both the steel making shops as secondary coolant replacement of Iron ore

47 Comparison with Iron ore Iron Ore Mill Scale Briquettes Fe (Total) % % Silica Load 5-6 % % Sulphur % % Sulphur Form In-Organic Organic Moisture 3-5 % < 2% Fines % 5-10 % Intangible Benefits Flame Shoot-up X Difficult to handle in Rainy Season X Source of Hydrogen X Red Fumes X ID Fan Perfomance Improved Bunker Jammng X

48 Summary JSW steel is front runner in adopting innovative and novel technologies for its operation with wide range of raw materials. Continuous Innovations being carried out for sustainable growth. Innovation cell is created to monitor status and encourage employee. Innovation online portal created for logging the innovations

49 Thank You