Practical Difficulties Associated with the Indian Coal Washeries: A Case Study

ABSTRACT

Beneficiation of lower grade coal continues to play a vital role for Indian coal industries, and it brings newer challenges to maintain its competitiveness in the global coal market. Studies have shown that the actual clean coal yield in most of the Indian coal washeries is much lower than that of the theoretical yield. Improper quantification of raw coal qualities and inappropriate maintenance of operating conditions for the processing equipments are often believed to be the two major causes for this lower yield. So, the importance of accurate quantification of these raw coal qualities has been demonstrated in this article. In addition, maximization of the plant yield has been illustrated through a case study. The results indicate that the yield could be increased up to 64.83%, which is nearly 21.64% higher than the plant’s actual yield. This study has been carried out in two stages: Firstly, variation of available coal quality and the presence of near gravity material have been quantified, and secondly, maintenance of constant incremental quality approach has been verified.

KEYWORDS:

• Coal cleaning
• constant incremental quality
• distribution curve
• near gravity material
• spreadsheet

Acknowledgments

The authors are thankful to all the staff members of CIMFR, Dhanbad for providing valuable support at various stages of this work. Sincere gratitude is also extended to the coal companies that provided the samples for this study. Finally, the authors express their sincere thanks to all colleagues who directly or indirectly contributed for the successful completion of this study.

Funding

The authors express their sincere thanks to Department of Science and Technology (Ministry of Science and Technology) of the Indian Republic and the National Council for Scientific and technological development—CNPq of the Ministry of Science, Technology and Innovation of the Federative Republic of Brazil (Project I.D.: INT/Brazil/P-04/2013).

Additional information

Funding

The authors express their sincere thanks to Department of Science and Technology (Ministry of Science and Technology) of the Indian Republic and the National Council for Scientific and technological development—CNPq of the Ministry of Science, Technology and Innovation of the Federative Republic of Brazil (Project I.D.: INT/Brazil/P-04/2013).