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ABOUT SLRM SLRMetaliksiscertifiedbyQMSISO9001:2008, EMS ISO14001:2004andOHSAS 18001:2007 in 2015 Located near Hospet, World heritage center and steel city of Karnataka, spread out in more than 200 acres of land with capacity of 0.24 Million ton per annum Pig iron produced is of the best quality standards with customer satisfaction Remain at the heart of the iron-ore mines with ample scope to grow and prosper, both nationally as well as internationally. we also mindful of our responsibility towards the environment and its protection. 2
FACILITIES BFcapacityof262M 3,SinterPlant25M 2 andcpp6mw UnderProjectareEOF,LRF,VD,CCMandRollingMill SinterPlantisavaluableassettoSLRM It ensures higher quality of products and better economic strategy for the plant. Enabled with circular machine for agglomerating iron ore fines and fluxes to produce useful BF burden. Ensure effective permeability of gases, thereby increasing productivity in the BF It helps in improving energy efficiency, aids higher productivity and reduces coke and flux consumption. 3
INTRODUCTION OF SINTER The maximum utilisation / consumption of Sinter in Blast Furnace depend on Commercial benefits and technically suitability for BF Operations As on today sinter has become the widely accepted and preferred burden material in Blast Furnaces. Almost there is no Blast Furnace operating without Sinter nowadays The Sintering Technology was developed for the treatment of the waste fines of Iron ore Coke Limestone Dolomite Metallurgical waste 4
ADVANTAGES OF SINTER IN BF OPERATION Avoid / eliminate the raw fluxes charge in Blast Furnace Improves the permeability and smoothen the blast furnace operations ( hence sinter is highly porous material) Better indirect reduction of the burden Will increase the productivity Decrease the coke rate with consistent quality of the hot metal Increased granular zone and minimise (narrow) the cohesive zone of the blast furnace Metallurgical wastages which are generated inside the plant can be used effectively Economically cheaper than the lump ore. 5
COMMERCIAL BENIFITS The Price difference between sinter and iron ore should be as more as possible to get commercial benefits of sinter consumption in BF Always sinter price should be low when compared with iron ore. ( For the month of Dec 2016 difference is Rs. 72/- only) Productivity and cost benefits are more if we charge more sinter at low price As on today we are getting approx Rs. 500 /- benefit due to Sinter use, per MT of Hot metal. 6
QUALITY For successful running of the Blast Furnace, recommended quality of sinter is as follows. PHYSICAL QUALITY: +60mmsize 5%max (ASLOWASPOSSIBLE) -5mmsize 5%max (ASLOWASPOSSIBLE) Tumbler Index(TI) > 69 Abrasive Index(AI) < 6 (AS LOW AS POSSIBLE) RDI 22 27 (REDUCTION DEGRADATION INDEX) RI 65 70 (REDUCIBILITY INDEX) 7
QUALITY QualityandstrengthofthesintermainlydependsonBasicity(CaO/SiO 2 ),alwaysshouldmeet thebfrequirementsdependingonthesintercharged/ratioinbf. Theeffectoftheself fluxingsinterisabigassetforbfoperations. CaO(from Limestone) and MgO(from Dolomite) in Sinter, eliminate the direct feeding of the fluxinbfwhichminimisesthecostofthehotmetalandsintermaybechargedupto80% safely. It improves the productivity of the BF and minimise the coke(fuel) consumption and reduction of the burden material inside the furnace will be faster with consistent quality of the hot metal. 8
QUALITY FeOshouldbeoptimum,8 10%always If Al 2 O 3 is < 2.3 then FeOshould be maintained 8-9 % If Al 2 O 3 is >2.3 then FeO should be maintained 9-10 % IfFeOismore Sinter will become more brittle causing more fines generation cause for furnace continuous hanging increases coke rate in blast furnace IfFeOisless Sinter will be weak causing more fines generation lead to furnace continuous hanging and furnace may get chilled 9
QUALITY Ifaboveexpectedqualitysinterwillbereplacedwithironoreinblastfurnacemaximum ratio(80 85%)ofsintercanbeusedsafely Production cost of the sinter to be considered while using the sinter in blast furnace (which is depending on the cost of raw materials for sinter making). 10
Selection of Raw Materials To improve the productivity and quality of sinter following requirements to be fulfilled Iron Ore Fines Size should be < 8 mm with Fe (T) = > 62% SiO 2 & Al 2 O 3 as low as possible 0.15 mm Micro fines (-100 Mesh) is Max 25% (as low as possible) More micro fines need more fuel consumption for sinter and kills the permeability on bed Size > 8 mm = Max 5% (as low as possible,) will not participate in sintering process Fraction of 2 mm to 5 mm should be as higher as possible for better sintering process But normally we use to get Iron Ore Fines which is having < 100 mesh (-0.15 mm micro fines) minimum of 25% and 15% to 20% +8 mm size 11
ON LINE SCREENING FOR IRON ORE FINES Duetoonlinescreening ofironorefineswecanaddextravaluetothefinesbychargingin Blast Furnace, so that we will get economical advantage EXAMPLE CALCULATION : AsontodaycostdifferencebetweentheLumpOreandIronOreFinesisRs.1000/- approx ForSinterNetProductionof25500MTperMonth@950Kg SpecificConsumption Required quantity of Iron Ore Fines is 24225 MT approx If +8mmsizematerialconsideredas 10%onaverageinorefines. MonthlyIronOreFinesrequiredis26915MT, andoversizequantityis 2690MT 2690x1000=Rs.26,90,000 /Month @Rs.3.23CrperYEAR 3.87Cr@Rs.1200 Difference & 4.84Cr@Rs.1500Difference. 12
Selection of Raw Materials Coke Fines 1mmto3mmsizecokebreezeshouldbe85to90%withminimumFC 76%.Thesame material will minimise the fuel consumption and will distribute the heat throughout the sinter bed effectively which helps us in making good quality sinter. Productivity and quality are determined by the coke combustion behaviour during sintering process. Due to the density deference between iron ore fines and coke fines, cokefinesformlayeronthesurfaceofrawmixballs/nodules. Suctiontemperaturewillincreasewithincreaseincokeuptocertainlimit.Thisisdueto when coke gets burn it liberates temperature and starts agglomeration. During agglomeration the bed gets shrink and forms voids. Through these voids suction take place along with temperature. When coke exceeds its limit beyond the requirement it forms thick stickers on hearth and drops suction and temperature. Sometimes top layer of the bed becomes hard and restrict suction, resulting drop in suction temperature. 13
Selection of Raw Materials Flux Limestone and Dolomite are used as flux materials ( Both 10 to 40 m size) which will be crushed and used in process with size of 1 mm to 5 mm, should be 80 to 85% always. Metallurgical wastes Flue dust and GCP dusts (from BF) are being used at present by collecting from proportionate bunkers. SMS & Rolling Mill is in Project stage and planned to use EOF Slag, SMS Scale & Mill Scale etc along with flue dust in future 14
PROCESS REQUIREMENT OF SINTER Proper Burden for Quality Sinter making as required by BF Operation Moisture(Water)additiontotheRawmixinPMD&SMD(7to8%Moisture) LoadingofRawmixonMachinebed Ignition with proper flame length by maintaining required Ignition Furnace temperatureat1050 0 Capprox Proper Sintering and cooling CrushingofHotSinterCakeinsinglerolecrusher Propercoolingincooler(below100 0 Ctemperature) Nosuctionleakagesshouldbethereonthesintermachine NumberoffallsfromcoolertoBFshouldbeminimum (Toavoidfines generation) 15
SINTER PLANT PROCESS FLOW CHART Iron ore Fines GCP Dust Quick Lime Lime stone BF Return Dolomite Coke Breeze Material Distribution Primary Mixer Drum Secondary Mixer Drum 25M 2 Annular Machine Single Role Crusher Head ESP Flue Gases Hot Screen +5 mm -5 mm Chimney Cooler Tail ESP Sinter to Blast Furnace Chimney 16
BEST ACHIEVEMENTS SO FAR Received Uttam Suraksha Puraskar from National Safety Council Wehavebeencertified byqmsiso9001:2008, EMS ISO14001:2004andOHSAS 18001:2007(IMS) during last year HighestProductionachievedsofaris1168MT/day@1.95Productivity (against 1080 Mt/days@ 1.80 Productivity, designed) Average 99% plant availability, monthly Sinterreturnfinescontrolled(-5mmsize) <15% SinterPlantisthebesthousekeepingareawithhighgreenery andgotawardforthebest housekeeping& best safety practice in SLR Every month achieving 100% safety compliances. AveragesinterconsumptioninBFis75to80% 17
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