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PRESENTATION ON

“CONVERSION OF STOKER FIRED BOILERS TOFLUIDISED BED BOILERS”

CII

NATIONAL SEMINAR ON BOILER & STEAM SYSTEMS

BY: MR.M.MURUGANANTHAM

M/s CETHAR VESSELS LIMITED - TRICHY

12 & 13 MARCH - 2008

THE ACCORD METROPOLITAN CHENNAI

? INCORPORATED IN THE YEAR 1981.

? COMMENCED MANUFACTURING IN 1984.

? 973 BOILERS AND 11 POWER PLANTS WERE COMMISSIONED SO FOR.

? LAST FINANCEIAL YEAR TURNOVER 2006-2007 USD 273MILLION

? EMPLOYEES :2341

? OVERSEAS OFFICES : 2, BRANCH OFFICES :7 (INDIA).

? THE COMPANY’S VISION IS TO MANUFACTURE AND SELL ANY BOILER,ANY CAPACITY AND POWER PLANTS UPTO 125 MWANYWHERE IN THE WORLD AND TO ENGINEERING AND EXECUTE POWER PLANT UPTO 800 MW IN INDIA.

? INFRASTRUCTURETOTAL LAND AREA –8,47,363 m²TOTAL COVERED PRODUCTION SHOP AREA –89,148 m²

? ANNUAL TONNAGE CAPACITY IN METRIC TONNES 97800 (PRESSURE PARTS)

COMPANY PROFILE

? ATMOSPHERIC FLUIDISED BED COMBUSTION BOILERS

? CIRCULATING FLUIDISED BED COMBUSTION BOILERS.

? TRAVELLING GRATE BOILERS

? OIL/GAS FIRED BOILERS

? HEAT RECOVERY STEAM GENERATORS.(HRSG)

? WASTE HEAT RECOVERY BOILERS.(WHRB)

? FIXED GRATE BOILERS.

? SHELL TYPE BOILERS.

? RETROFITTING OF EXISTING BOILERS INTO FBC SYSTEM

? CENTRIFUGAL FANS

? ELECTRO STATIC PRECIPITATOR

? MCC & CONTROL PANELS

? EPC CONTRACT FOR POWER PLANTS.

ABOUT CVL PRODUCTS

? M/s CVL COMMISSIONED SO FOR 973 BOILERS

? TOTAL NO OF BOILERS CONVERTED TO FBC =106 NOS.

? TRAVELLING GRATE CONVERTED TO FBC = 56 NOS

? M/s CVL CONVERTED VARIOUS MAKES OF TRAVELLING GRATE BOILERS WITH DIFFERENT CAPACITY INTO FLUIDISED BED COMBUSTION SYSTEM

CONVERSION BOILER DETAILS

TEMP.

(°C)PRESSURE

(kg/cm² )CAPACITY

(TPH)CUSTOMER

4203250M/s RAYALASEEMA

4806575M/s ACC

3302815M/s BIRLA CORPORATION

51010590M/s GHCL

36018.522M/s BIRLA CORPORATION

4102825M/s BIRLA CORPORATION

4806245M/s RAYALASEEMA

4856666M/s ACC

49661.590M/s CHATTISGARH

TOTAL NUMBER OF STOKER CONVERTED TO FBC = 56 NOS SOME OF THEM ARE AS FOLLOWS

TEMP.

(°C)PRESSURE

(kg/cm² )CAPACITY

(TPH)CUSTOMER

4003335M/s VAM ORGANIC CHEMICALS LTD

4956580M/S.AMBUJA CEMENTS LTD

4604536.280M/S.BALLARPUR INDUSTRIES LTD

48084.00107M/S.RAMA NEWS PRINT AND PAPERS LTD

4153040M/S.DIAMOND CEMENTS LTD

49661.5081.70M/S.SHRIRAM FERTILIZERS & CHEMICALS LTD

4303033M/S.APPM LTD

4253040.835M/S.TATA CHEMICALS LTD

51584105M/S.BINANI CEMENT LTD

TOTAL NO OF OTHER BOILERS CONVERTED TO FBC = 50 NOS SOME OF THEM ARE AS FOLLOWS

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? MANY TECHNOLOGIES HAVE EVOLVED TO CONVERT A WIDE VARIETY OF FUELS TO ALTERNATIVE FORM OF ENERGY.

? ONE IMPORTANT TECHNOLOGY IS THE MECHANICAL STOKER.

? ALL STOKER ARE DESIGNED TO FEED FUEL ONTO THE GRATE WHEN IT BURNS WITH UNDER GRATE AIR (UGA) PASSING UP THROUGH IT AND OVER FIRING AIR (OFA) PASSING OVER IT.

? THE GRATE IS LOCATED WITHIN THE LOWER FURNACE AND IS DESIGNED TO REMOVE THE ASH RESIDUE AFTER COMBUSTION.

? EVOLVING FROM THE HAND FIRED BOILER ERA, MECHANICAL STOKER / GRATE SYSTEM DESIGN ARE AVAILABLE TO BURN WIDE RANGE OF FUELS FOR INDUSTRIES,SMALL UTILITY AND COGENERATION APPLICATION.

? IN ADDITION TO BURNING ALL FORM OF COAL,OTHER FUELS BURNED INCLUDE SLUDGE,WOOD WASTE AND BIOMASS (e.g. WOOD, BARK, STRAW, BAGASSE, RICE HUSKS, ALMOND SHELL, COFFEE GROUNDS)AS WELL AS RESIDENTIAL , AGRICULTUREAL AND COMMERCIAL REFUSE

INTRODUCTION ABOUT STOKER

? FLUIDISED BED COMBUSTION TECHNOLOGY WAS APPLIED TOLARGE SCALE UTILITY BOILER UNITS TO EXPLORE NEW WAY OF BURNING SOLID FUELS,ESPECIALLY HIGH SULPHUR COAL IN AN ENVIRONMENTALLY ACCEPATBLE AND EFFICICENT MANNER.

? IN CONCEPTOF FLUIDISED BED, BURN FUEL IN AN AIR SUSPENDED MASS OF PARTICLES.BY CONTROLLING BED TEMPERATURE AND USING RENGENTS SUCH AS LIMESTONE TO CAPTURE SULPHUR IN BED

? EMISSION OF NITORGEN OXIDE (NOx) AND SULPHUR DIOXIDE(SO2) CAN BE CONTROLLED DUE TO LOW COMBUSTION TEMPERATURE

? ADDITIONAL BENEFIT OF FBC INCLUDES WIDE FUEL FLEXIBILITY AND ABILITY TO COMBUST FUELS SUCH AS BIO MASS OR WASTE FUEL, WHICH ARE DIFFICULT TO BURN IN CONVENTIONAL SYSTEM BECAUSE OF THE LOW HEATING VALUE,LOW VOLATILE MATTER,HIGH MOISTURE CONTENT OR OTHER CHALLENGING CHARACTERISTICS.

INTRODUCTION ABOUT FLUIDISED BED COMBUSTION

? THE EXISTING GRATE WILL BE REPLACED BY FLUIDISING BED

? THE EXISTING OVER BED FEEDING WITH STOKER WILL BE REPLACED BY UNDER BED PNEUMATIC FEEDING SYSTEM

? BED EVAPORATOR ADDED

? SUPER HEATER SHALL BE INTRODUCED IF REQUIRED

? ASH HANDLING BELOW FURNACE WILL BE REPLACED WITH SIMPLE SYSTEM

COMPONENT REPLACED FOR CONVERTING STOKER FIRED TO FLUIDISED BED COMBUSTION

COMPARISON BETWEEN STOKER AND FLUIDISED BED COMBUSTION

PRIMARY AIR SYSTEM IS REQUIRED FOR FUEL TRANSPORTION IN TO BED

PRIMARY AIR SYSTEM NOT APPLICABLE

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BED ASH DRAIN WITH COOLER AND PNEUMATIC / MECHANICAL CONVEYING SYSTEM

BED ASH HOPPER WITH SUBMERGE BELT CONVEYOR

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UNDER/OVER BED FEEDING SYSTEM IS POSSIBLE

ONLY OVER BED FEEDING SYSTEM

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BED SUPER HEATER SHALL BE INTRODUCED

BED SUPER HEATER IS NOT APPLICABLE

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BED EVAPORATER WILL BE INTRODUCED

BED EVAPORATER IS NOT APPLICABLE

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FLUIDISED BED WITH AIR BOX SYSTEM

TRAVELLING/FIXED GRATE

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FLUIDISED BED COMBUSTIONSTOKERS.NO

DESIGN PARAMETERS COMPARISON BEFORE AND AFTER MODIFICATION

4566.514194.50m²HEAT TRANSFER AREA05

150150ºCFLUE GAS OUTLET TEMP04

ºCKg/cm²

TPH

UNITS

505 ± 10105

70

BEFORE

510 ± 5TEMPERTAURE03105PRESSURE02

90CAPACITY01

AFTERDESCRIPTIONS.NO

CUSTOMER: M/S.GHCL LTD

STOKER FIRED BOILER

ARRANGEMENT

BEFORE MODIFICATION

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FLUIDISED BED BOILER ARRANGEMENT

AFTER MODIFICATION

AFTER MODIFICATIONBEFORE MODIFICATION

TRAVELLING GRATE ARRANGEMENT

BEFORE MODIFICATION FLUIDISED BED ARRANGEMENTAFTER MODIFICATION

FLUIDESEDBED ARRANGEMENT

AFTER MODIFICATIONTRAVELLING GRATE ARRANGEMENT

BEFORE MODIFICATION BEFORE MODIFICATION FUEL FEEDING WITH PNEUMATIC ARRANGEMENT

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AFTER MODIFICATION FUEL FEEDING WITH SPREADER ARRANGEMENTAFTER MODIFICATIONBEFORE MODIFICATION

? HIGH SULPHUR FUEL CAN BE FIRED EFFICIENTLY WITHOUT MUCH GENERTAION OF SOx BY DOSING LIMESTONE IN BED ITSELF

? LOW COMBUSTION TEMPERATURE OF THE ORDER OF 750°C -900°C FACILITATES BURNING OF FUEL WITH LOW ASH FUSION TEMPERATURE PREVENTS NOx FORMATION,REDUCE HIGH TEMPERTAURE CORROSION AND EROSION AND MINIMISES ACCUMLATION OF HARMFUL DEPOSITS DUE TO LOW VOLATISATION OF ALKALI COMPONENTS

? BOILER EFFICIENCY WILL BE IMPROVED WHEN COMPARED WITH STOKER FIRED BOILER

? OPERATION FLEXIBILITY IS MORE IN FBC BOILER COMPARE TO STOKER FIRED BOILER

? BOILER CAPACITY CAN BE INCREASED DUE TO HIGH HEAT TRANSFER RATE OVER A SMALL HEAT TRANSFER AREA IMMERSED IN THE BED

? ASH HANDLING BELOW FURNACE IS SIMPLE SYSTEM WHEN COMPARE TO STOKER FIRED BOILER.

ADVANTAGES OF CONVERTING THE STOKER FIRED BOILER TO FLUIDISED BED COMBUSTION SYSTEM

THANK YOU