Determination of the Effect of Different Additives in Coking Blends Using a Combination of in Situ High-Temperature 1H NMR and Rheometry
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- 作者：Miguel C. Dí ; az ; Karen M. Steel ; Trevor C. Drage ; John W. Patrick ; and Colin E. Snape
- 刊名：Energy & Fuels
- 出版年：2005
- 出版时间：November 2005
- 年：2005
- 卷：19
- 期：6
- 页码：2423 - 2431
- 全文大小：193K
- 年卷期：v.19,no.6(November 2005)
- ISSN：1520-5029
文摘
High-temperature 1H NMR and rheometry measurements were carried out on 4:1 wt/wt blendsof a medium volatile bituminous coal with two anthracites, two petroleum cokes, charcoal, wood,a low-temperature coke breeze, tyre crumb, and active carbon to determine the effects on fluiditydevelopment to identify the parameters responsible for these effects during pyrolysis and to studypossible relationships among the parameters derived from these techniques. Positive, negative,and neutral effects were identified on the concentration of fluid material. Small positive effects(ca. 5-6%) were caused by blending the coal with petroleum cokes. Charcoal, wood, and activecarbon all exerted negative effects on concentration (18-27% reduction) and mobility (12-25%reduction in T2) of the fluid phase, which have been associated with the inert character and highsurface areas of these additives that adsorb the fluid phase of the coal. One of the anthracitesand the low-temperature coke breeze caused deleterious effects to a lesser extent on theconcentration (7-12%) and mobility (13-17%) of the fluid material, possibly due to the highconcentration of metals in these additives (ca. 11% ash). Despite the high fluid character of tyrecrumb at the temperature of maximum fluidity of the coal (73%), the mobility of the fluid phaseof the blend was lower than expected. The comparison of 1H NMR and rheometry results indicatedthat to account for the variations in minimum complex viscosity (
*) for all the blends, both themaximum concentration of fluid phase and the maximum mobility of the fluid material (T2L)had to be considered. For individual blends, two exponential relationships have been foundbetween the complex viscosity and the concentration of solid phase in both the softening andresolidification stages but the parameters are different for each blend.
*) for all the blends, both themaximum concentration of fluid phase and the maximum mobility of the fluid material (T2L)had to be considered. For individual blends, two exponential relationships have been foundbetween the complex viscosity and the concentration of solid phase in both the softening andresolidification stages but the parameters are different for each blend.