1598 would depend on whether stamp charging technology is being used before feeding coal into coke oven or not. In case of stamp-charging technology is used, upto 30% of indigenous washed coking coal (18% ash) may be blended with imported coking coal and the demand of indigenous washed coking coal (18% ash) shall be 40.8 Mt by 2031. If stamp-charged coke oven batteries are not adopted in future, the demand shall be 27.2 Mt with blending ratio of 20% of indigenous washed coking coal (18% ash) with imported coal [3]. However, as per NSP–2017, the target coke rate for 2030–31 is 325 kg/thm, whereas globally, modern blast furnaces are already operating at less than 300 kg/thm. If the specific coke consumption is achieved at 325 kg/thm, the total coking coal requirement will reduce to about 116 Mt, and the corresponding requirement of domestic coking coal will decline to around 35 Mt (considering a 30% blending ratio). Figure 1- Illustration of the trends in domestic coking coal production, indigenous metallurgical washed coal produced and import of coking coal in India over the past five years As of April 1, 2025, India possesses ~37.4 Bt (billion tonnes) of coking coal reserves. Out of these 37.4 Bt reserves, ~5.1 BT is proved reserves of prime coking coal, ~17.8 Bt of proved reserve of medium coking coal. The coking coal are predominantly located in Jharia and Bokaro coalfields, account for ~ 90% of total coking coal reserve in India [4]. The upper seam coals of Jharia and Bokaro coalfields, which are good quality coking coals is depleting at a faster rate leaving behind the inferior quality (high ash) in lower seams (Seam VIII and below) which are low volatile. These low volatile coals fall into the category of medium coking coal and have ash content greater than 35%. These low volatile coals are of high rank (Rr % > 1.2 %) [LVHR], high inertinite content, low reactive content (30-45%), low volatile matter content (18 to 22 %), high ash (>35%) and hence, with lower coking propensities with difficult cleaning characteristics. Indian coals are drift origin and hence tend to have high ash and difficult washability characteristics because of the presence of high near-gravity material (NGM) since the impurities are intimately present in the coal matrix. NGM possesses a relative density close to that of the separating liquid or dense medium employed to separate the coal and the impurities present in raw coal. NGM becomes more difficult to separate due to the fact that it takes very long to settle in the dense-medium because its density is similar to that of the medium. This enhances the likelihood of material that is supposed to report to float incorrectly reports to sinks and vice versa, thus adding up to more misplaced material". It is the amount (%) of material with relative density in + 0.1 of separation density. The modern high efficiency plants are able to separate quite easily even when NGM (RD50±0.1) is as high as 25 wt%. In LVMC coals, NGM content is usually high (~50%) at the preferred specific gravity of cut, mean raw coal ash is up to 35-50%. Owing to close mixing of finely disseminated coal and shale such coals possess very poor liberation properties; even progressive crushing to 15/13 mm does not yield much to clean coal. The washability potential of such coals are so low that the available old washeries with conventional washing technologies cannot provide coals of ash 17-18% as required by indigenous metallurgical industries and cannot compete with foreign coals due to poor yield of clean coal at 17-18% ash. Therefore, such coals are supplied to other industry, contrary to increasing metallurgical coal demand for coke production and hence wasting of limited coking coal reserves. Subsequently, it was found that washed LVMC coal possess coking potential and can be used for coke making in steel industry through blending. Observing this, these LVMC coals are placed under coking coal category as washery grade, W-V (ash- above 35% up to 42%) & W-VI (ash- above 42% up to 49%). The country has a moderate reserve of LVC coal, about 40% of the total coking coal reserve. In the year 202425, production of LVMC coals (W-V &VI) in India was 26.5 Mt, about 40% of the total coking coal production (66.5 Mt). However, out of 66.5 Mt of coking coal produced in FY 2024-25, only 18 Mt of coking
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