Effect of Blending on Operational Performance and Generation Costs of an Indian Power Plant Dr Anthony Williams Anthony.Williams@abmylec.com.au A&B Mylec Dr Oliver Scholes Oliver.Scholes@vale.com Vale International SA 1st IEA CCC Coal Quality Workshop 9-10 November 2016 New Delhi India
Background – Moatize Mine Vale’s Moatize mine produces a hard coking coal product and a thermal coal product. Mine is ramping up to an output of 22mt of coal per year. Coal Quality Calorific Value – 6050 kcal/kg GAR Moisture - 5% AR Ash – 24% AR Volatile Matter – 20 % AD HGI – 72 IDT AFT – 1480 oC (red)
India – Coal Fired Power Plants Very high coal production & coal fired power capacity Numerous coal mines with large rail network Railways
Mundra Power Plant - Coal Supply Options 5x800MW Supercritical Design on Indo/SA blend Indo coal contract 1 coal in blend is fixed
Coal Quality Increasing Energy
Blend Modelling – MarketMastor™ Domestic freight+Port+Taxes Shipping+Port Scenarios Power Plant Model Market Model Power Plants Specs Evaluate Output Coals Coal Quality Mines Blending Trade
Plant Limitations – Studied coals Moatize Raw Coals
Binary and Ternary Blends
Ternary Blends
All Blends Accepted Blends Low No. of blends High No. of blends Ternary Blends All Blends Accepted Blends Low No. of blends High No. of blends
Pulveriser Performance Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Mill Erosion Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Boiler Efficiency Top 50 Blends Accepted Blends All Blends
Combustion performance Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Carbon-in-ash Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Dust Emissions Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends SO2 Emissions Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Auxiliary Power Top 50 Blends Accepted Blends All Blends
Operating and Maintenance Costs Top 50 Blends Accepted Blends All Blends
Top 50 Blends Accepted Blends All Blends Total Generation Cost Top 50 Blends Accepted Blends All Blends
Electrical Output (GWh/a) Top 50 Blends Accepted Blends All Blends
Best Blends Generation Costs (US$/MWhr) BEST BEST BLENDS BLENDS Sent out Energy (GWhr/a)
POWER PLANT PERSPECTIVE Power plant confirmed a close match between the actual power plant performance and the desktop analysis. Agreed with the technical recommendation of using Moatize coal in 20% blend where possible. Ash deposition potential of currently used coal reduces by 20% when using Moatize coal. Blend usage has resulted in higher boiler efficiency, improved mill performance, reduction in mill power, and reduction in power for draft system (reduction in auxiliary power use). Mundra power plant are continuing to use Moatize coal
CONCLUSIONS A different point of view is required when evaluating coals for blending Negative attributes can be smoothed over by blending Large number of possible blends can be evaluated Blending can improve plant performance and reduce fuel costs Beneficial in applying plant limitations to blend coal quality specs, not on raw coals Moatize coal was determined to blend very favourably with the existing coal used at Mundra Power Plant Moatize coal blended better than other coals Limit to how much can be added but evaluations and plant trials showed coal can be considered as an excellent blending coal Power plant trials determined Moatize coal improved plant performance and decreased costs
ACKNOWLEDGEMENTS Thanks to A&B Mylec for providing permission to prepare and present at the IEA CCC workshop Thanks to Vale for sponsoring the trip costs for the workshop