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By Om Prakash & Aadil Keshwani: Indian coking coal reserves are depleting rapidly. Coking coal is invaluable, with washed coal vital for coke preparation, a key component in steelmaking. This paper explores optimizing clean coal yield with lower ash percentages through advanced beneficiation equipment and newly developed requisites such as reagents and flocculants. 1. Today coking coal washeries are to follow the most modern coal beneficiation technology to optimize the clean coal yield % at lower ash%. The state-of-the-art technology flow sheet for coking coal is depicted below Mostly prepared feed size range (-) 50 mm (+) 0.5 mm is beneficiated through two stages of Heavy Media Cyclone. This ensures the least percentage of misplacement of materials which adds to clean coal yield. If the laboratory test supports, then the following stages of washing can be adopted. Size Fraction                        Process Route  (-) 50 mm (+) 1.5 mm                      by Heavy Media Cyclones (-) 1.5 mm (+) 0.5 mm                     by Spiral Concentrators (-) 0.5 mm                                          by Flotation.  The de-slimed feed (-) 0.5 mm is subjected to fine beneficiation circuit. By introducing a pulp density adjusting tank between conditioner and flotation will be a good measure to maintain optimum pulp flotation density. To optimize the flotation reagents consumption normally the pulp conditioning is done at 30% solid by weight then after that conditioned pulp is diluted to required flotation density around 10% solid by weight. This adjustment is taken care of by Pulp Density Adjusting Tank. By adopting this route clean coal yield can be optimized 2. Use of most efficient JFE design Heavy Media Cyclones which can guarantee the lowest imperfection values. 3. DSM Design JFE HM Cyclones are a much better option to ensure higher efficiencies 4. Use of most efficient DSM design hydro cyclones which can guarantee the lowest imperfection values. JFE Hydro cyclones are most efficient. For classification and thickening process, the JFE design hydro cyclone battery is very helpful prior to the thickener. This helps in optimizing thickener size and good process water in recirculation in the circuit. 5. Use of efficient Magnetic Separators with required gauss strength for HMC circuit will guarantee the lowest magnetite consumption i.e. 800 grams per tonne of ROM coal. This low-intensity wet Magnetic Separator is a very long magnetic pick-up zone. This is very efficient for dense media recovery. 6. Use of Spiral Concentrator for size fraction (-) 1.5 mm (+) 0.5 mm helps in optimizing the yield of clean coal at low ash%. Spirals are: 7. Use of a Flotation System can add on yield of clean owing to the following features: 8. Use of Inclined Plate Settlers- IPS by which clarification is achieved when upstream velocity is low enough to allow solids to report to the inclined plates by using latest developed flocculent Inclined Plate Settlers have many practical advantages. 9. Use of the latest design fines clean coal dewatering devices like Pressure Filter/ Horizontal Vacuum Belt Filter which adds GCV on the product. The driving force of this filtration method is the pressure differential across the cake. A higher-pressure drop will give a faster dewatering rate and a lower residual moisture, as smaller voids are emptied from liquid.  Service and maintenance requirements are low for Pressure Filter. Hence the least downtime which helps in betterment of yield of clean coal.   10. The use of Belt Filter Press for fine-tiling dewatering investment is justified. Belt Filter Press remains a preferred technology for dewatering of fine tailing from coal washery. 11. By using instruments to measure the yield and the underflow and overflow medium densities and how the data can be used to optimize the operation of the heavy media cyclones. This can also be one of the appreciable efforts to optimize the yield of clean coal at lower ash%. 12. Use of the right quality and granulometry of magnetite in case of heavy media separators. Specification of ground magnetite for Heavy Media Cyclone Circuit: Specification of Magnetite Content                                              Specification             Fe3O4 (Magnetite Content)             98.5%             Specific Gravity                                  4.90-5.15             Particle Size                                        90% passing 45 Microns.             Fe Content                                          68-70% By use of right quality and ground size of magnetite in the heavy media circuit the maintenance of consistent cut point can be ensured which is mostly helpful for the coal feed having high +/- 0.10 NGM %. This is also a step towards optimization clean coal yield. Specification of reagents and flocculent Use of proper flotation reagents in place of conventional frother and collector can add value in the yield of clean coal. Nalco Water flotation reagents for frother and collector has established an excellent result in coal flotation industries. Conventional Reagents & Flocculent        Latest Developed Reagents &Flocculent                                                                                     By NALCO WATER Frother- Pine Oil                                                      Frother- N 9840 Collector- Diesel Oil                                                 Collector- N 88001 Thickener Flocculent-Alum                                    Thickener Flocculent-Anionic- A83384 Cationic- A102 Plus    Conclusion: By using most modern design of equipment items installed in the coal beneficiation plants can play a vital role for optimizing yield of clean coal at lower ash %. Similarly, by using the required grade of magnetite for Heavy Media Circuit, latest developed flotation reagents and flocculants for settling aids yield of clean coal can be very well optimized in the coal beneficiation plants. Coking coal deposits for our country are very limited and washed coking coal should be used judiciously. A good number of fine coal beneficiation circuits are installed in BCCL and CCL but most of fine coking coal beneficiation circuits are not in operation. By making these fine circuits operational we gain heavily on clean coal yield and steel sectors can reduce the import of coking coal. References: About Authors: Om Prakash obtained his Master of Technology from IIT Kharagpur (India) in Mineral Engineering with a specialization in Coal Preparation in the year 1979 followed by a Postgraduate in Business Administration from Pondicherry Central University. He has been closely associated with the Denver USA technology for Coal Flotation, Separator Poland, and Fives Cail Babcock France technologies