TY - JOUR
T1 - Combustion and Agglomeration of Coal-Oil Mixtures in Furnace Environments
AU - Miyasaka, K.
AU - Law, C. K.
N1 - Funding Information:
This research was initially sponsored by the Pittsburgh Energy Technology Center, Department of Energy under Grant No. FGOI-77ETl0660. It was completed with the support of the Office of Basic Energy Sciences, Department of Energy, under Contract No. EG-77-S-02-4433. J. Demeter and J. Ekman of the Pittsburgh Energy Technology Center, and A. Kestin and J. Sangiovanni of the United Technologies Research Center kindly provided us with most of the samples tested. C H. Wang assisted with the initial experimentation.
PY - 1980/10/1
Y1 - 1980/10/1
N2 - 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. Parameters varied include the volatility of the oil, the concentration and size of the coal particles, the residence time, the intensity of blowing, and the effects of water and surfactant addition. Results substantiate the formation of coal particle agglomerates upon depletion of the volatile oil components, and emphasize the importance of oil volatility and external convective motion on COM combustion. In particular agglomeration 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.
AB - 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. Parameters varied include the volatility of the oil, the concentration and size of the coal particles, the residence time, the intensity of blowing, and the effects of water and surfactant addition. Results substantiate the formation of coal particle agglomerates upon depletion of the volatile oil components, and emphasize the importance of oil volatility and external convective motion on COM combustion. In particular agglomeration 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.
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U2 - 10.1080/00102208008952425
DO - 10.1080/00102208008952425
M3 - Article
AN - SCOPUS:0019284317
SN - 0010-2202
VL - 24
SP - 71
EP - 82
JO - Combustion science and technology
JF - Combustion science and technology
IS - 1-2
ER -