3657
Exploring Pelletization as a Method to Use Low-Grade Chromite
Overburden in India
Deepak Nayak
CSIR-Institute of Minerals and Materials Technology Bhubaneswar
Ranjita Sahu, Nilamadhaba Sahu
TATA Steel Limited Jamshedpur
Sunil Kumar Tripathy
TATA Steel Limited Jamshedpur
Natural Resources Research Institute (NRRI), University of Minnesota Duluth
ABSTRACT: Pelletization was used to utilize low-grade Indian chromite overburden samples. The effect of
basicity, binder content, induration temperature, and time on the metallurgical properties of the pellets was
examined. The optimal conditions for producing pellets with desired properties were determined to be a binder
content of 0.5 wt.%, basicity of 0.2w5, induration temperature of 1250 °C, and 10 min for low-grade siliceous
overburden. Low-grade ferruginous overburden required higher basicity (1.0) and temperature (1300 °C) for
the same time. X-ray diffraction was used to reveal the phase transformation and strengthening mechanism
during the induration process.
Keywords: Chromite Overburden Pelletization Induration Nickel Consolidation Behaviour
INTRODUCTION
The demand for stainless steel has experienced a significant
surge in recent years due to the rapid growth in urban-
ization, automotive, construction, and home appliances
(Gao et al., 2019 Bhaskar &Bhoi, 2021). Stainless steel
is a highly sought-after material known for its exceptional
tolerance, ductility, corrosion resistance, and recyclabil-
ity (Ghosh &Chatterjee, 2008 Gardner, 2019 Rabi
et al., 2022 Feng et al., 2023). Nickel, a major compo-
nent responsible for imparting these desirable properties,
accounts for over 60–70% of the stainless steel industry
(Xiao et al., 2021 Pandey et al., 2023). However, in India,
the supply of nickel is limited despite high demand, and
the government has recently categorized it as a “Critical
Mineral.” Currently, the entire demand for nickel is met
through imports. To overcome this situation, there is a
need to explore the effective utilization of chromite over-
burden from the Sukinda Valley, Odisha, which is rich in
nickeliferous limonite and is one of the significant nickel
occurrences in the country. Every year, opencast chromite
mining generates about 10 million tons of overburden, and
an estimated 170 MT of chromite overburden deposits
exist in huge volumes (Prasad et al., 2021 Nayak et al.,
2023). Extracting nickel from the overburden is a challeng-
ing task as it is primarily bound with iron oxides like goe-
thite, making it a complex mineralogy and heterogeneous
ore mixture.
Exploring Pelletization as a Method to Use Low-Grade Chromite
Overburden in India
Deepak Nayak
CSIR-Institute of Minerals and Materials Technology Bhubaneswar
Ranjita Sahu, Nilamadhaba Sahu
TATA Steel Limited Jamshedpur
Sunil Kumar Tripathy
TATA Steel Limited Jamshedpur
Natural Resources Research Institute (NRRI), University of Minnesota Duluth
ABSTRACT: Pelletization was used to utilize low-grade Indian chromite overburden samples. The effect of
basicity, binder content, induration temperature, and time on the metallurgical properties of the pellets was
examined. The optimal conditions for producing pellets with desired properties were determined to be a binder
content of 0.5 wt.%, basicity of 0.2w5, induration temperature of 1250 °C, and 10 min for low-grade siliceous
overburden. Low-grade ferruginous overburden required higher basicity (1.0) and temperature (1300 °C) for
the same time. X-ray diffraction was used to reveal the phase transformation and strengthening mechanism
during the induration process.
Keywords: Chromite Overburden Pelletization Induration Nickel Consolidation Behaviour
INTRODUCTION
The demand for stainless steel has experienced a significant
surge in recent years due to the rapid growth in urban-
ization, automotive, construction, and home appliances
(Gao et al., 2019 Bhaskar &Bhoi, 2021). Stainless steel
is a highly sought-after material known for its exceptional
tolerance, ductility, corrosion resistance, and recyclabil-
ity (Ghosh &Chatterjee, 2008 Gardner, 2019 Rabi
et al., 2022 Feng et al., 2023). Nickel, a major compo-
nent responsible for imparting these desirable properties,
accounts for over 60–70% of the stainless steel industry
(Xiao et al., 2021 Pandey et al., 2023). However, in India,
the supply of nickel is limited despite high demand, and
the government has recently categorized it as a “Critical
Mineral.” Currently, the entire demand for nickel is met
through imports. To overcome this situation, there is a
need to explore the effective utilization of chromite over-
burden from the Sukinda Valley, Odisha, which is rich in
nickeliferous limonite and is one of the significant nickel
occurrences in the country. Every year, opencast chromite
mining generates about 10 million tons of overburden, and
an estimated 170 MT of chromite overburden deposits
exist in huge volumes (Prasad et al., 2021 Nayak et al.,
2023). Extracting nickel from the overburden is a challeng-
ing task as it is primarily bound with iron oxides like goe-
thite, making it a complex mineralogy and heterogeneous
ore mixture.