TITLE:
A process for producing Low Sulphur Fe base Metal and Steel.
FIELD OF INVENTION:
This invention relates to a process for producing Low Sulphur Fe base
metal and Steel.
BACKGROUND OF THE INVENTION:
There is no effective process and Desulphurising compound available for
doing desulphurization in Induction furnace.
OBJECTS OF THE INVENTION:
An object of this invention is to propose a process for producing low
sulphur Fe base metal and steel.
Another object of this invention is to propose a process to reduce the
sulphur content in the induction furnace and steel making ladles.
Further object of this invention is to propose a process to overcome the
restriction in reducing sulphur in induction furnace.
Yet another object of this invention is to propose a process for producing
Fe base metal and steel having sulphur content less than 0.020 %.
Still further object of this invention is to propose a process for producing
low sulphur Fe base metal and steel which will be beneficial to meet the
current demand.
BRIEF DESCRIPTION OF THE INVENTION:
According to this invention there is provided a process for producing low
sulphur Fe base metal and steel comprising:
A process for producing low sulphur fe base metal and steel comprising:
Preparing Fe base charge
melting 60 %- 75 % of Fe base charge
subjecting the melt to a temperature range to more than 1380°C
adding desulphurising compound (JCADF3) batch wise & melt down
balance 25 % - 40 % charge
raking out slag as much as possible
desulphurising compound (JCADF3)addition will continue along with
partly slag off till the desired level of sulphur achieved
DETAILED DESCRIPTION OF THE INVENTION:
In practice sulphur is considered as harmful impurities except in few
grades of steel where it is used as an alloying additive. The technique of
removing sulphur from the bath is done in reducing atmosphere. The
newly developed Desulphurising compounds [JCADF3] is found very
effective in removing Sulphur from the bath. The compositions of these
compounds are as follows:
• Size distribution : 100 % less than 1 mm
Basic Reaction Principle:
Newly developed Desulphurising compound [JCADF3] which has certain
% CaC2 which takes part in removing sulphur from the Fe base charge mix
of Induction furnace metal by reduction reactions
In this newly developed compound Calcium Carbide is the main
constitute which takes part in Desulphurising reactions, this compound
also has CaF2 which helps in improving slag fluidity, a vital necessity for
desulphurization & slag raking efficiency. The other elements present in
this compound like CaO, AI2O3, Si02 helps in enhancing the DS efficiency.
This basic reaction steps between sulphur. & the compound is as follows:
¦ Chemical reaction:
CaO + FeS = CaS + FeO
CaC2 + FeS+2FeO —? CaS + 3Fe +2CO
¦ Reaction steps:
o Vaporizing of S into gas interface
(S)->{S}
o Physical absorption of S at GaC2 -surface
o S-sink at CaC2 -surface
o Diffusion of C and S through CaS product
layer
The complete detail is shown in the accompanying Figure 1 Process Flow
Chart.
EXAMPLES:
a} As per the finished product specification necessary Fe base charge
mix heed to be made. Then melt down 60 %- 75 % Fe base charge
mix. After melt down of Fe base 60 %- 75 % charge mix following
procedure to be followed.
b) Take Sample & temperature
c) If temperature is more than 1380°C , then add desulphurising
compound JCADF3 Compound batch wise & melt down balance
25 % - 40 % charge ( addition quantity of newly developed
desulphurising compound ( JCADF3) will depend on the initial &
desired final sulphur)
d) Rake out slag as much as possible
e) Take sample
f) The process of adding newly developed desulphurising compound
(JCADF3) will continue along with partly slag off till desired level
achieved
g) Tapped the furnace at desired temperature
Some of the results obtained by addition of newly developed
Desulphurisng compound are as follows:
Other findings:
Aim: S less than 0.020 % after treatment.
Chemical required: Desulphurisng compound (JCADF3)
Procedure: As mentioned earlier.
The bath temperature of the Induction Furnace is kept within the range of
1350°-1700°C. The quantity of compound added is about 0.55 % -1.40 %
of charge weight to reduce sulphur from 0.040 % to a lower percentage
which is less than 0.012 % in 10 tons to 14 tons charge mix. However this
quantity o desulphurising compound can reduce sulphur further in higher
capacity Induction furnace.
The present invention comprise of desulphurising compound which
comprises certain % of CaC2, CaO , CaF2, AI2O3, SiC>2, MgO, Fe203, MnO
& HO2 and systematic process of addition for achieving sulphur level less
than 0.020 % after treatment in Induction furnace.
WE CLAIM:
1. A process for producing low sulphur Fe base metal and steel
comprising:
A process for producing low sulphur Fe base metal and steel comprising:
Preparing Fe base charge
melting 60 %- 75 % of Fe base charge
subjecting the melt to a temperature range to more than 1380°C
adding desulphurising compound (JCADF3) batch wise & melt down
balance 25 % - 40 % charge
raking out slag as much as possible
desulphurising compound (JCADF3)addition will continue along with
partly slag off till the desired level of sulphur achieved
2. The process as claimed in claim 1, wherein the said desulphurising
agent comprises of:
3. The process as claimed in claim 1, wherein the addition ot said
desulphursilig compound is repeated till the desired level of low sulphur Fe
base metal and steel is obtained.
4. The process as claimed in claim 1, wherein the bath temperature for
heating is in a range of 1350-1700°C.
5. The process as claimed in claim 1, wherein the said desulphurising
agent is added between 0.55% to 1.40% of charge weight to reduce
sulphur from 0.040% to a lower percentage which is less than 0.012% in 10
tons to 14 tons charge mix.

A process for producing low sulphur Fe base metal and steel comprising:
Preparing Fe base charge
melting 60 %- 75 % of Fe base charge
subjecting the melt to a temperature range to more than 1380 ° C
adding desulphurising compound. (JCADF3) batch wise & melt down
balance 25 % - 40 % charge
raking out slag as much as possible
desuiphurising compound (JCADF3) addition will continue along with
partly slag off till the desired level of sulphur achieved