Mining Publication: Effect of Coal Type and Oxyfuel Combustion Parameters on Pulverised Fuel Ignition
Original creation date: August 2007
Oxyfuel combustion is currently one of the principal technological options being considered for capturing carbon dioxide from pulverised coal power plants. In oxyfuel combustion, coal is burnt in a mixture of recycled flue gases and added oxygen instead of in air. In principle this yields a flue gas containing only carbon dioxide, water vapour and small amounts other impurities. Oxyfuel combustion is superficially similar to combustion in air, but there are inevitable differences. This paper describes ignition tests on pulverised coal suspensions using a suite of coals of different rank and from different countries of origin and over a range of oxygen and coal concentrations of interest for oxyfuel combustion. The ignition tests were carried out using the National Institute for Occupational Safety and Health (NIOSH) 20-litre explosion chamber. The purpose was to determine how easily the various coals ignite and burn in mixtures of O2 and CO2 compared to their combustion in air. The residual char volatile and ash contents for the ignition residues were measured using a thermogravimetric analyser (TGA), allowing Q factors (i.e., enhancement in apparent volatile yield due to higher heating rates and/or heterogeneous reactions) to be determined and compared. An ignition index has been derived from the explosion and char data. This index has been used to rank low volatile coals for ignition propensity in air. The results show that to obtain ignition and combustion comparable to that in air, the oxyfuel O2-CO2 gas mixture must contain over 30% O2.
Authors: C Man, JR Gibbons, KL Cashdollar
Conference Paper - August 2007
NIOSHTIC2 Number: 20032660
2007 International Conference on Coal Science and Technology, August 28-31, 2007, Nottingham, United Kingdom. Nottingham, U.K.: University of Nottingham, School of Chemical and Environmental Engineering, Nottingham Fuel and Energy Centre, 2007 Aug; :1-9
See Also
- Factors Affecting Coal Particle Ignition Under Oxyfuel Combustion Atmospheres
- Gas Sorption and Transport in Coals: A Poroelastic Medium Approach
- Methane Diffusion Parameters for Sized Coal Particles: A Measuring Apparatus and Some Preliminary Results
- Methane Emissions from Gassy Coals in Storage Silos
- Performance Comparison of Rescue Breathing Apparatus
- Reducing Hazards in Underground Coal Mines Through the Recognition and Delineation of Coalbed Discontinuities Caused by Ancient Channel Processes
- Removing Methane (Degasification) from the Pocahontas No. 4 Coalbed in Southern West Virginia
- Reservoir Engineering Considerations for Coal Seam Degasification and Methane Control in Underground Mines
- A Review of the Mechanisms of Gas Outbursts in Coal
- Safe and Economical Inerting of Sealed Mine Areas
- Page last reviewed: 9/21/2012
- Page last updated: 9/21/2012
- Content source: National Institute for Occupational Safety and Health, Mining Program