ABOUT JSW SALEM PLANT

JSW Steel Ltd, Salem works, part of USD 11 Billion JSW Group, is India’s largest integrated special steel plant located in Salem, Tamilnadu

with installed capacity of 1 MTPA

MAIN PRODUCTS

Wide product ranges from 5.5 mm to 240 mm More than 700 grades developed

Coils - 5.5 to 23.5 mm Round Bars- 20.5 to 60 mm

Flats- 60 x 7 to 101 x 20 mm Round Blooms-56 to 200 mm

OUR CUSTOMERS

Products Key Customers

As Cast MSL, Karamtara, Wheels India, Lucchini, Italy

Flats Jamna Industries, Soni Auto Ltd

Bars Madhur Engineers Ltd, Southern Steel and Forgings

Coils Aradhya Steel ltd, Mitco Wires Ltd

RR/RCSBharat Forge LTD, Happy Forge Ltd, Echjay Industries, MM Forgings…

REDUCTION IN COKE MOISTURE BY UTILIZING WASTE FLUE GAS & IT’S EFFECT IN BF OPERATION

REJI MATHAI, V.RAVICHANDRAN, M.S. RAO, T.K. NAHA

INTRODUCTION

JSW Steel Limited (JSWSL), Salem Works, operates eco- friendly Coke oven plant, which Produces 0.5 million tons per annum of metallurgical coke through three Heat recovery batteries comprising of 120 ovens. And through waste heat recovery boilers 30 MW power is being generated.

SUMMARY OF COKE MAKING PROCESS

At JSW, Coke is manufactured by heating of the Suitable coal blend in the absence of or controlled air inside the Silica refractory lined oven at the temperature of 1250 to 1300 c for about 68 to 72 hours coking time. During the carbonization process all VM present in the coal is burnt and produce heat. The remnant solid mass after carbonization is called Hot Coke, which is pushed out and quenched with water, segregated in to various size for the BF use.

OBJECTIVE OF THE THEME

The sensible heat of the hot waste

flue gas generated in the coke oven

process which was partly being let out

through the chimney is used to dry

the coke

2 to 3 % Reduction in Coke moisture.

A NOVEL CONCEPT

HOT FLUE GAS ANALYSIS

Sl.No. Parameter Unit Value

1 PM mg/Nm3 40.2

2Sulfur die Oxide(SO2)

mg/Nm3 79.4

3Nitrogen Oxide(NO2)

mg/Nm3 21.6

4Carbon mono oxide (CO)

% 0.2

5 OXYGEN O2 % 6.0

6 Carbon die oxide

CO2

% 12.0

1500 TPD INHOUSE 1500 TPD INHOUSE INSTALLATION OFINSTALLATION OF

COKE DRYING UNIT COKE DRYING UNIT

AN UNIQUE & FIRST AN UNIQUE & FIRST OF IT’S KIND IN INDIAOF IT’S KIND IN INDIA

PROJECT IMPLEMENTATION

OPERATING PARAMETER

Sl. No Description Unit Actual

1 FD Fan RPM 1220

2 Gas flow M³/Hr 110000

3 FD Fan Inlet temperature ° C 240-250

4 Coke Bunker Inlet Temperature ° C 220-230

5 Coke Outlet Temperature ° C 110-130

6 Suction MMWC 96-120

Coke Dryer FD Fan

COKE DRYING METHOD

The hot waste flue gas at temperature 1050 °C is extracted.

Diluted to 250°C by the atmosphere air .

Hot gas Blown to coke dryer bunker through FD fan.

The coke is retained for one and half hour .

The coke moisture content reduces from >5.5 to <2.5%.

The emergency vent & water spry system is provided .

Dust dust free environment is ensured during coke loading.

OUTCOME

MOISTURE EFFECT IN BF OPERATION

BF#1 RESULT – BEFORE AND AFTER

Coke Drying Unit

Fuel Rate

Kg/THM

Sinter %

Slag VolumeKg/THM

HBTDeg.C

Steamgm/Nm3

Coke Moisture

%

Corrected Fuel RateKg/THM

Before 591 73 355 977 20 5.49 593

After 588 74 377 988 31 2.34 582

Difference 3.14 11

Observations : Based on the data study, it was observed that for every 1% reduction in coke moisture, there was a reduction of around 3.5 Kg/THM in fuel rate Note : Shutdown and low production days data not considered for data study Study was made on Corrected fuel rate to eliminate the effect of variations in sinter usage, slag volume etc.

TANGIBLE BENEFIT

Coke Moisture Reduction – 3.0%

Coke Saving – 10.5 Kg/THM (Approx)

Coke Cost – RS 13,000 /MT

(Approx)

Hot metal Production – 75,000 MT/ MONTH

Cost Saving Per Year – Rs 12.84 Cr/ Annum

CONCLUSION

Coke moisture reduction > 2.5% consistently. Significant Reduction in fuel rate at the BF. An energy conservative initiation. Recurring benefits . Life & Safety of the chimney is enhanced by

minimum let out of hot flue gas.

ACKNOWLEDGEMENT

The authors are very thankful to Mr. M S Pillai, Associate Vice-President and

Mr. V. Ravichandran, Sr.Manager CPP-2

for Constant support and initiative to complete the coke dryer project.

THANKSTHANKS