Characteristics of the HGI Fractions of the Indian Coal Blended with Imported Coals


K. H. Arunkumar
V. Saravanan


The blends of a high ash Indian coal with three coals of different foreign origins -Australia, Russia and Indonesia were
subjected to HGI testing as per ASTM D 409 and the resulted fractions obtained in the coarser and finer portions of ASTM
200 mesh (75 microns) were assessed for their characteristics in respect of proximate and ultimate parameters, alpha
quartz and combustion reactivity. The similar studies were also carried out for the parent coals. HGI values were found
additive in case of Indian-Indonesian coal blends and the same was found non-additive in respect of Indian-Russian and
Indian-Australian coal blends. Considerable variation in properties was observed in the coarser and finer fractions of the
ASTM 200 mesh for parent Indian and Indonesian coals compared to parent Australian and Russian coals. This indicates
the disproportion of the coals and coal blends particles during the sieving process after subjecting to HGI test. The variation
of alpha quartz content in the coarser and finer fractions indicate that there is a segregation of free minerals in the coarser
and finer fractions. The conversion plots obtained through TGA for the coarser and finer fractions indicate that there is no
maceral segregation.


How to Cite
Arunkumar, K. H. ., & Saravanan, V. . (2022). Characteristics of the HGI Fractions of the Indian Coal Blended with Imported Coals. Power Research - A Journal of CPRI, 17(2), 121–124.


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