Post on 24-Dec-2015
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