The combustion characteristics of freely falling and suspended mono-sized coal-oil mixture (COM) droplets in heated air were investigated by studying the quenched samples using scanning electron microscope. Agglomertion is not expected to be a serious problem for COM with No. 6 oil, although addition of oils with higher volatility widens the volatility differentials between the oil and coal components such that the agglomerate formation, heating, ignition, and thereby the total burning times are significantly prolonged. Addition of water may cause droplet swelling and fragmentation due to internal bubbling which, however, can be inhibited by moderate amount of internal circulation induced by the external convective motion. The possibility that agglomeration may be prevented under high pressure combustion is also discussed.
All Science Journal Classification (ASJC) codes
- Mechanical Engineering