11.6 RESEARCH

11.6 RESEARCH

Previous  |
1
2
3
4
5
6
7
8
9
10
11
12
13
|  Next

RESEARCH


Steam fluidized bed drying of Victorian brown coal ...
Continued from previous page

Analysis of the moisture re-adsorption of dried Victorian brown coals

Because of Victorian brown coal’s strong hydroscopic potential, fully dried coal will very quickly re-adsorb moisture if left exposed to the atmosphere; however the impact of the drying method on the re-adsorption potential has not been examined. This is important because of the possibility of delays in combustion of the fuel.

Any moisture which re-adsorbs will lower efficiency once it is combusted, so understanding the impact of drying methods may allow better control of the drying conditions.


Determination of the drying kinetics of Victorian brown coal with steam and hot gas as drying mediums

While drying kinetics have already been investigated through different drying technologies, coals and conditions, relatively little information is publicly available regarding using steam as a fluidising medium in conjunction with Victorian brown coal.

The influence of system parameters on the drying of coal is well-established; however, the relative change in drying ratios between similar properties at different fluidisation mediums has yet to be discussed. Using a laboratory scale fluidised bed, these aspects have been investigated and can be found in Figure 2 and Stokie et al. (2013).


Figure 2: Typical steam fluidised bed drying kinetic data

Development of a drying model to predict drying rate in fluidised beds

While fluidised bed models of coal drying do exist, there are still gaps in current methods of calculation. We are working to develop a model that can capture the underlying kinetics and attrition of the dried coals, while being easy enough for engineering use.

Once validated, the model will be expanded to include a particle set sized system instead of a single averaged particle diameter. Finally, the attrition results will be incorporated into the existing model, to increase the accuracy of the drying model.

This project is currently well advanced, and has enjoyed collaboration with international universities including the University of Science and Technology, Liaoning.


For further information on current work please feel free to contact Professor Sankar Bhattacharya (sankar.bhattacharya@monash.edu), David Stokie (david.stokie@monash.edu) or consult any recent publications:

  • D. Stokie, J. Yu, A. Auxilio, S. Bhattacharya, Coal Drying and Dewatering for power generation – Current Status, Research and Development Needs, International Conference on Coal Science and Technology, International Conference on Coal Science & Technology Oviedo, Spain 2011
  • D. Stokie, M.W. Woo, S. Bhattacharya, Comparison of Superheated Steam and Air Fluidized-Bed Drying Characteristics of Victorian Brown Coals, Energy & Fuels, 27 (2013) 6598-6606
  • M.W. Woo, D. Stokie, W.L. Choo, S. Bhattacharya, Master curve behaviour in superheated steam drying of small porous particles, Applied Thermal Engineering, 52 (2013) 460-46
  • D. Stokie, S. Bhattacharya, J. Tanner, Physical and Chemical Properties of Steam Fluidized Bed Dried Coal, The 38th International Technical Conference on Clean Coal & Fuel Systems Clearwater, Florida, USA, 2013, pp. 11
  • Tahmasebi, Arash; Yu, Jianglong; Han, Yanna; Yin, Fengkui; Bhattacharya, Sankar; Stokie, David, Study of Chemical Structure Changes of Chinese Lignite upon Drying in Superheated Steam, Microwave and Hot Air, Energy & Fuels,
  • D. Stokie, M.W. Woo, S. Bhattacharya, Attrition of Victorian Brown Coal in a Fluidized Bed Drier, In Submission.


For more information on this research, go to the previous page of this e-newsletter.




View print friendly version




Previous  |
1
2
3
4
5
6
7
8
9
10
11
12
13
|  Next