Model for Beneficiated Coal

1. Model for Beneficiated Coal dr kalyan sen Prof. Emeritus, Bengal Engineering & Science University,Shibpur Director, Central Coalfields Ltd. Former Director, Central Fuel Research Institute and Central Mining Research Instutute, Dhanbad. 9th International Summit & Expo POWER INDIA 2007 25-27 October 2007 Mumbai, India.

2. Coal Scenario • Likely to treble in the next decade • Largest consumer – Power Utilities • Most of the TPP burn coal without any upgrading • Coal cleaning is one of the important action areas for achieving reduction in CO2 emission per kWh of electricity produced.

3. Barriers for Coal Beneficiation • Difficult washability characteristics of Indian Coals due to Geological reasons. • Back dated mining and preparation technologies • Uncertainty associated with the economic impact on the down stream processes.

4. Silver Linings • Indian coals contain low Sulphur • Combustibility is good due to Geological reasons • Coal washed up to 55% elementary ash (equivalent to 34% overall ash) has good combustion properties

5. Action Desired • To transform from a qualitative understanding of the effect of coal quality parameters to a quantitative domain • An economic model considering several factors involved throughout the ‘mine-energy’ chain like:- cost of coal, logistics, beneficiation technologies, efficiency improvements & environment benefits

6. Models for Beneficiated Coal • Coal Data Base • Simulation of Coal Beneficiation Process • Cost Model

7. Coal Data Base • Full scale size-wise washability data • Fraction-wise chemical, heat value and ash composition data • Prediction of the quality parameters of the cleans • Studies on Combustibility of washed coal and slagging and fouling problems by Drop Tube Furnace tests

8. Options of Beneficiation Process • Destoning followed by whole coal beneficiation • Combination of Dry and Wet schemes • Blending partly washed coal with unwashed lower size fractions • Use of the concept of “limiting elementary ash” to identify the optimum ash content for power generation • Multi-product washing schemes

9. Simulation of Coal Beneficiation Process • Computer simulation of washability data (from module1) and efficiency of washers to identify optimum operation conditions to produce maximum yield at desired quality • Based on the washability potential the best economic option should be chosen

10. Cost Model • Cost and Quantity of raw coal • Transportation costs ( mine to washery and washery to power plant) • Scope and cost of Reject utilization • Savings in GHG generation at different levels of cleaning • Savings due to reduction in maintenance, ash handling, etc. • Savings due to improvement in energy efficiency

11. Conclusions • New coal washeries of total capacity 100mt/yr should be created within a decade. Modules of 2.5, 5 and 10my/yr are techno-economically justified • Regulatory framework should be enforced to fix up the price of washed coal considering cost of production and direct & indirect benefits • Model for Beneficiated Coal should be utilized to help in decision making.

12. THANKS