368 7. As per the process developed in LIMN model for the same coal by using the washability data and simulating it as per process flow described at 2.2 above, the balance of products obtained in LIMN with top size of raw coal of 10 mm is mentioned in Table 8. Table 8 - Balance of products as per LIMN model 4. CONCLUSION From the above results following can be concluded: 1. Reducing the top size of raw coal feed to the washery increases liberation of coal particles, thereby improving the yield of cleans at 18% ash by about 2% in the coarse coal circuit. 2. The overall yield of washery grade, W–V coal improves by 4.9%, and W-VI by 4.6%, when advanced beneficiation technologies such as Reflux Classifiers / Fine DMC are used for intermediate size fraction and Column Flotation Cells in place of Mechanical flotation. 3. By leveraging the advanced beneficiation technology, Dahibari washery will be able to produce an additional 0.8 Lakh Te /year of clean coal and 1.0 Lakh Te/year from Bhojudih washery, resulting in an increamental profit of ~ 18 Million USD for Bharat Coking Coal Limited (BCCL) from these two washeries. This figure may further increase with rising international coking coal price. 4. By 2030-31, the projected washing capacity for coking coal will be around 61 Mtpa (CIL, SAIL and Tata combined) with avg. yield of 42% at 18% ash level. With the use of advanced beneficiation technology available, the yield may be improved to 46-47%. 5. Washing 61 Mtpa of raw coking coal will generate ~ 28.5 Mtpa (assuming avg. yield of 46.5%) of indigenous washed coal metallurgical coal, sufficient to meet 80% of the domestic demand for coking coal and about 25% of total coking coal requirements. 6. This enhancement will reduce import of coking coal from current 90% to 75%, saving significant foreign exchange reserves and insulating the steel sector from international market price volatility. 7. The low volatile coking coals (W-V/VI) of lower seams of Jharia Coalfields can achieve yield of >30% at the required quality if the coal is properly beneficiated with state-of-the-art technology. Equipment Clean Coal Middlings Rejects Yield % Ash % Yield% Ash% Yield % Ash% Primary HM Cyclone 17.8 17.9 Secondary HM Cyclone 18.6 38.3 18.6 63.1 Fine HM Cyclone 5.9 19.5 5.2 47.0 Column Flotation 3.1 16.5 3.8 37.7 Jig 29.9 67.4 Total 26.7 18.0 27.6 39.8 45.7 65.9
RkJQdWJsaXNoZXIy MTM0Mzk2