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150 MW NBEIL CFBC BOILER REFRACTORYRefractory in CFBC Boiler Fluidizd bedJ-sealAsh return pipeCycloneInlet ductCombustion chamberScreen coils Combustion chamber a) Lower part b) Upper part c) screen coils

Cyclone systemInlet Ductcyclone Bed /Ash return system a) j-seal Outlet systemcod2nd passLower partOutlet Duct

1)BurnerWind box 2)3)4)5)Burner

FurnaceOperating conditions: Temperature T = 850 950C Partially reducing atmosphere Strong abrasion due to turbulent bed (sand, ash)Demands on the refractory system: Abrasion resistance ( ABR < 7 ccm) CO resistance Low permanent linear change

Combustion chamberLower part

Refractory system : Refractory material: Heavy high alluminia Thickness: 80 mmAnchoring through studs on tube wallBituminous paint 2 mm thk Furnace

Wind boxOperating conditions: Temperature T = 850 950C Partially reducing atmosphere Strong abrasion due to turbulent bed

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Refractory system : Refractory material: Middle weight shaped material Thickness: 100 mmSS 310 AnchorS welding on fin plate of tube wallBituminous paint 2 mm thk on Anchors

Wind boxScreen coilsOperating conditions: Temperature T = 850 950C Partially reducing atmosphere Strong abrasion due to turbulent bed (sand, ash)Demands on the refractory system: Abrasion resistance ( ABR < 8 ccm) CO resistance Low permanent linear changeScreen CoilsRefractory system : Refractory material: Heavy high alluminia Thickness: 80 mmAnchoring through studs on coilsBituminous paint 2 mm thk on anchors

Screen CoilsInlet duct

Operating conditions:Strong abrasion through ash/bed erosionTemperature T = 800 950CFlue gas flow touching the duct wallDemands on the refractory system:Abrasion resistance (ABR < 9 ccm)CO resistanceLow permanent linear changeCyclone Inlet duct

Refractory system Inlet Duct Multilayer system on steel wallSS310 anchors welded to steel casing and painted with bituminous black of 2mm thkBack up with lightweight heat insulated pouring material 240 mm thk High strength castable refractory with120 mm thk

Bull nose10

Cyclone Target ZoneRefractory system target zone Multilayer system on steel wallRefractory: High strength castable refractory with 120 mm thkBack up : Liight weight heat insulated pouring material of 240 mm thk

STEEL (COLD WALL ) CASINGINSULATING CASTABLEINSULATING LAYERHIGH STRENGTH WEAR RESTING CASTABLECyclone Target Zone

Operating conditions:Strong abrasion through ash / bed erosion (ABR < 9 ccm)Temperature T = 800 950CFlue gas flow touching the inlet wallRckfhrzyklonCyclone

Cyclone cylinder and cone

Cyclone cylinder and cone

Demands on the refractory s ystem:Abrasion resistance (ABR < 10cm3)CO resistanceLow permanent linear changeCyclone

Light weight brickCeramic blanket

Refractory system Multilayer system on steel wallRefractory: High strength castable refractory with 120 mm thkBack up with Light weight heat insulated pouring material with 240 mm thk

Wear resistant brick J-sealJ-sealAsh return pipe

Demands on the refractory system:Abrasion resistance (ABR < 7 cm3)CO resistanceLow permanent linear changeRefractory system : Refractory material: Heavy high alluminia with thk 120 mmBack up with light weight heat insulated pouring material 170 mm thk ss310 Anchoring through casing material Bituminous paint 2 mm thk

J-sealOperating conditions:Strong abrasion through ash/bed erosion Temperature T = 800 950C

Cross over Duct

CODDemands on the refractory system:Abrasion resistance (ABR < 10 cm3)CO resistanceLow permanent linear change

COD

Refractory system : Refractory material: High strenght wear resisting pouring material with 110mm thkBack up with light weight heat insulated pouring material 240 mm thkss310 Anchoring welded through casing Bituminous paint 2 mm THK

BurnerOperating conditions: Temperature T = 850 950C Partially reducing atmosphere Strong abrasion due to turbulent bed (sand, ash)Demands on the refractory system: Abrasion resistance ( ABR < 10 ccm) CO resistance Low permanent linear changeBurner

Refractory system : Refractory material: High strenght wear resisting pouring material with 100mm thkBack up with light weight heat insulated pouring material 160 mm thkss310 Anchoring welded through casing Bituminous paint 2 mm THKBurnerREFRACTORY MATERIAL 150 MW PP - BOILER REFRACTORY (CHINA PRODUCTS)S.NOAREADESCRIPTIONADDITIVEWATER QTYREMARKS1CYCLONE,COD & PARTICAL RETURN DEVICE(FIRST LAYER) Light Weight Heat Insulating Pouring Material (50kg/Bag)CA-50-G6 (17.5 kg/Bag)20 -22 Liters2CYCLONE & CODHigh Strength Wear Resisting Material (YG-JZ-13(50kg/Bag)CA-70 ( 3.5kgs/Bag)3.5 Litersshutter to be removed after 12 hours of application3CYCLONE & ECONOMISERLight Weight Brick(Insulation Brick)Slurry (50kg/Bag)Equal amount of waterSoak 12 Hrs Before Use4CYCLONEWear Resistant BrickWear Resistant Mortor (50kg/Bag)Equal amount of Binder(Wear Resistant Binder)-5FURNACE & PARTICAL RETURN DEVICEHeavy High Alumina Pouring material (YG-GJ-15)CA-70 ( 3.5kgs/Bag)3.5 litersshutter to be removed after 12 hours of application6PLENUMMiddle Weight Shaped MaterialCA-50-G6 ( 8.75 kgs )5-7 Liters-7FURNACE OUTLET ,SCREEN COILS , OVER HEAD,CAGEWALL AND ECONOMISER SUPPORTING BEAMWear Resisting castable Reractory (YG-GS-14)CA-70(1kg)Wear Resistant Binder(2.5 kgs premix time and 2.5 kgs at the time of mixing) Soak 12 Hrs Before Use by mixing 2.5 liters of binder 8FURNACE BED(FIRST LAYER)Middle Weight Heat Insulated pouring materialCA-50-G6 ( 8.75 kgs )5-7 Liters-INDIAN REFRACTORY PRODUCTS9ECONOMISER SUPPORT BEAM Phoscast-605.375 kgs Binder(10.75%) OR 3350ml1.75- 2 liters(3.5-4%)10BURNERS,J-SEAL AND FURNACEHypercast-80(LC-80)2.87 Litres(5.75%)11Insulcast-90029 Litres(58%)12CYCLONE,COD & PARTICAL RETURN DEVICE,FURNACE,CAGEWALLPhoscast-90 XR4.75 kgs Binder(9.5%) OR 2850ml1.75 Liters (3.5%)

Refractory propertiesCSevere erosion near to bull nose area

BeforeAfterCyclone Target area High strength castable refractory repaired with wear resistant Ccastable refractory24

BEFOREAFTERCyclone inlet joint repaired with Phoscast-90 xr

BEFOREAFTERCyclone bull nose area High strength castable refractory area repaired with Phoscast 90 xr

Before AfterRefractory failure in furnace at coal chute area

Before AfterFurnace area eroded patched with PHOSCAST-9O XR

Refractory failure in wind boxINFERIOR Design PARAMETERS

Inferior abrasion resistant property, low Volume Stability, low Strength refractory material used Velocity and particle profile more than design parameters it is said that an increase in 10 % of velocity can lead to an increase of erosion of 21 % in refractory liningImproper expansion jointsNot providing retainer plates at profile change areasSize and shape of pressed refractory / BricksWrong material selection, Faulty design, profile and pitch of anchorsInappropriate refractory lining thicknessNegligence of a possible alkali attack from the fuels especially from bio mass and coal based fuelsQuality of refractory materialUsage of expired or worn out refractory materialHaphazard storage of refractoryUsage of partially set or bags having lump formationUsing refractory from damaged bagsPoor Installation practicesUsage of sub standard quality of waterMore mortar between bricksUsage of more water percentage Adding 1 % of excess water can lead to 10 % reduction in CCS of castable Improper mixing sequence and mixing timeImproper welding of anchorsLong lead time for pouring refractory in to formsImproper compaction of castable refractory Over sized panels and wrong orientation of sameImproper of curing and form work removalImproper or insufficient dry outThe following things has to be taken care during the application:Proper handling & storing of refractory materials Proper execution plan.Good quality of water.Suitable welding electrode for the anchors.Proper welding of anchors and cleaning of slag.Proper applying Bituminous paint in the anchors/ provide PVC caps. Proper shuttering panelsProper mixing and placing of refractory castable as per manufacturer recommendation.Proper vibration of the castable in the shuttering.Providing expansion joint as per design.Proper de-shuttering and inspection of cast panels.Proper dry out of refractory.

PRECAUTIONS

Muller M/cVIbratorDigital weighing M/cTest tubeMaterials for refractory application