EFFECT OF DISPERSING AND STABILIZING ADDITIVES ON RHEOLOGICAL CHARACTERISTICS OF THE UPGRADED BROWN COAL WATER MIXTURE
DOI:
https://doi.org/10.30556/imj.Vol11.No1.2008.601Keywords:
Dispersing additive, stabilizing additive, rheology, apparent viscosity, yield stressAbstract
The preparation of upgraded brown coal water mixture (UBCWM) by using an Indonesian upgraded coal that was produced by an upgraded brown coal (UBC) process in pilot scale, was carried out to obtain the effect of dispersing and stabilizing additives on rheological behaviour of the UBCWM. Three kinds of anionic dispersing additives, naphthalene sulfonate formaldehyde condensate (NSF), polymethacrylate (PMA) and polystyrene sulfonate (PSS) and three kinds of stabilizing additives, carboxyl methyl cellulose (CMC) an organic material a derivative of cellulose, rhansam gum (S-
194) and gellan gum (S-60) some kinds of bio poly sacharide the trade mark of Dainippon Pharma- ceutical Co. Ltd. were used in this study. Results indicate that the addition of NSF 0.3 wt% together with S-194 0.01 wt% is effective in preparing UBCWM with good slurry ability and stability, based on its rheological characteristics (apparent viscosity at shear rate of 100 s-1 and yield stress at zero point of shear rate). Since the price of S-194 is expensive, the addition of CMC 0.01 wt% is also effective in preparing stable UBCWM.
References
Hashimoto, N., 1999. CWM: Its past, present and future, Coal Preparation Vol. 21, pp 3-22.
Saeki, T., Usui, H., and Ogawa, M., 1994. Effect of molecular structure of polysaccharide on the stability of coal water mixtures, Journal of Chemical Engineering of Japan, Vol 27, No. 6, pp. 773-778.
Tudor, P. R., Atkinson, D., Crawford, R. J., and Mainwaring, D. E., 1996. The effect of adsorbed and non-adsorbed additives on the stability of coal water suspensions, Fuel, Vol 75 No. 4 pp. 443-452.
Umar, D. F., Usui, H. and Daulay B., 2006a. Change of combustion characteristics of In- donesian low rank coal; due to upgraded brown coal process, Fuel Processing Tech- nology, Vol 87 No.11, pp. 1007-1011.
Umar D. F., Usui H., Komoda Y. and Daulay B., 2006b. Preparation of carbonized biomass water mixture and upgraded coal water mix- ture, Journal of Chemical Engineering of Ja- pan, Vol, 37 No. 11, pp. 1206-1212.
Usui, H. and Sano Y., 1984. Thixotropy of highly loaded coal water slurries, Journal of Chemi- cal Engineering of Japan, Vol 17, No 6, pp. 583-588.
Usui, H. and Sano, Y., 1986. Thixotropy and sta- bility of highly loaded coal water mixtures Proc. of World Congress III of Chemical En- gineering, Tokyo, pp 465-468.
Usui, H., Machibara, K. and Sano, Y., 1987. Ef- fect of stabilizing additives on the stability of coal water mixtures, Journal of Chemical En- gineering of Japan, Vol. 20 No. 2, pp 192-
Usui, H., Tatsukawa, T., Saeki, T. And Katagiri, K., 1997. Rheology of low rank coal slurries prepared by an upgrading process, Coal Preparation, Vol. 18, pp 119-128.
Usui, H., Tatsukawa, T., Saeki, T. and Katagiri, K., 1999. Upgrading of low rank coal by a combined process of vacuum drying and tar coating, Coal Preparation, Vol. 21, pp 71-81.
Willson, W. G., Farnum S. A., Baker G. G. and. Quentin G. H, 1987. Low rank coal slurries for gasification, Fuel Processing Technology, 15, pp. 157-172.
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