Page 12 - Steel Tech India eMagazine Volume April 2022

VOL. 16 • NO. 3 • April 2022

steel making covering de oxidising, de sulphurzing, de • Major product from these units are rebar which has
gassing and close chemistry finish were performed in got a good and growing market demand both in
ladle operation only. retail and project segments

today this secondary metallurgical process and in • These rebar units do focus on mainly local markets
particular ladle refining is an integral part of almost all rather than all India presence and therefore the
steel making process with perhaps only exception being delivered cost is low and have good business
induction furnace melted steel using a large quantity commercials.
of coal based DRI(cDRI) having high phosphorus current induction melting process is merely a re melting
and sulphur contents. this induction furnace steel process with largely with uncontrolled chemistry
making in India as commonly designated as secondary especially with regards to two important elements of the
sector of steel manufacturing is quite large with an steel viz P and S which hardly conform to an acceptable
output volume of nearly 30-35 Mtpa and thereforeis of quality for many end applications. In this context it is
criticalimportance. this huge capacity build up is quite worthwhile to keep in mind that I/F process works in
understandable due to mainly following reasons “What Goes in is What comes Out” principal and no
refining is possible here considering the limitations due
• CDRI, a metallic input for induction furnaces is
widelyavailable in India. In fact India is the largest to nature of Furnace Refractory lining etc. Only little
producer of cDRI in the world. this is a much reaction takes place in reducing mainly carbon by the
cheaper substitute of melting scrap which mostly high FeO content of the DRI especially when used in
imported in the country. bulk quantity.
• CDRI plants produce enough flue gas to put captive
power plants @ 2.5 MW capacity per 100 tPD
capacity of cDRI
• Entry barrier in terms of cost of investment for an
induction furnace based steel plant with back up
DRI and captive power plant integrated with a rebar
rolling mill is rather low compared to other processes
of manufacturing like eAF

• The dependence on grid power is low and so also
the own captive power cost
• The process is overall energy efficient and more so Fig. 2: Share of Induction Furnace Crude Steel Production
due to current practice of direct rolling of as cast in India
billets
Source: Metals and Electronics
• The cost of production is also highly competitive
Induction Furnace (IF) steelmaking in India:
exceptsome foundryunits, most of the induction
furnace steel in the country is utilized to make cast
billets and converting the samefinally into rebar and
other construction steel products in general. Induction
furnace units are a significant part of Indian steel
industry and merits a closer look on the embedded
potential for technology development in this field.

The melting process utilizes coal based DRI (CDRI) as
major input to the extent of nearly 70- 80 %, balance
being scrap and pig iron. Since this cDRI is produced
using sized iron ores /pellets and coal primarily, the
harmful ingredients like P/S arealmost fully absorbed
Fig.1: Typical Induction Furnace

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