407
The operating characteristics of cross-draft gasifiers are similar to downdraft
gasifiers. Air or air/steam mixtures enter through the side of the reactor and syngas
is drawn from the opposite side. These types of gasifiers respond rapidly to load
changes. The construction is not very complicated and high-quality syngas is produced. Cross-draft gasifiers are sensitive to changes in fuel composition and moisture content.
A typical entrained flow gasifier is represented in Fig. 3. Duchesne et al. [16]
used an inorganic element partitioning model to predict the performance of
entrained-flow petroleum coke gasification. They concluded that for higher O/C
ratio the carbon conversion increased significantly and the CO/CO 2 molar ratio of
syngas was sensitive toward O/C molar ratio. However, the CO/H 2 molar ratio of
syngas was sensitive toward operating temperature. The study also showed that the
ash output for the petroleum coke entrained flow gasification was less as compared
to that of coal feed. Zhang et al. [17] performed the statistical analysis and optimization of a entrained flow co-gasification of petcoke with coal. They studied the effect
of variation of steam and oxygen concentrations syngas (CO + H 2 ) and hydrogen
production. The study revealed that with an increase in oxygen concentration the
average production of hydrogen and syngas increases while for an increase in steam
concentration the production of syngas and hydrogen decreases. Also, for the higher
oxygen concentration fluctuation in the production of syngas and hydrogen inhibits
while for higher steam concentration their fluctuation becomes significant. The
optimum condition based on maximum syngas production with minimum fluctuation was obtained at 1.56% oxygen concentration with 50% steam concentration.
Rana et al. [18] performed the supercritical and subcritical water gasification of
asphaltene and petcoke in a hydrothermal reactor with varying reaction times
Fig. 2 A sketch of a typical fixed bed downdraft gasifier
Petcoke Gasification: Challenges and Future Prospects
The operating characteristics of cross-draft gasifiers are similar to downdraft
gasifiers. Air or air/steam mixtures enter through the side of the reactor and syngas
is drawn from the opposite side. These types of gasifiers respond rapidly to load
changes. The construction is not very complicated and high-quality syngas is produced. Cross-draft gasifiers are sensitive to changes in fuel composition and moisture content.
A typical entrained flow gasifier is represented in Fig. 3. Duchesne et al. [16]
used an inorganic element partitioning model to predict the performance of
entrained-flow petroleum coke gasification. They concluded that for higher O/C
ratio the carbon conversion increased significantly and the CO/CO 2 molar ratio of
syngas was sensitive toward O/C molar ratio. However, the CO/H 2 molar ratio of
syngas was sensitive toward operating temperature. The study also showed that the
ash output for the petroleum coke entrained flow gasification was less as compared
to that of coal feed. Zhang et al. [17] performed the statistical analysis and optimization of a entrained flow co-gasification of petcoke with coal. They studied the effect
of variation of steam and oxygen concentrations syngas (CO + H 2 ) and hydrogen
production. The study revealed that with an increase in oxygen concentration the
average production of hydrogen and syngas increases while for an increase in steam
concentration the production of syngas and hydrogen decreases. Also, for the higher
oxygen concentration fluctuation in the production of syngas and hydrogen inhibits
while for higher steam concentration their fluctuation becomes significant. The
optimum condition based on maximum syngas production with minimum fluctuation was obtained at 1.56% oxygen concentration with 50% steam concentration.
Rana et al. [18] performed the supercritical and subcritical water gasification of
asphaltene and petcoke in a hydrothermal reactor with varying reaction times
Fig. 2 A sketch of a typical fixed bed downdraft gasifier
Petcoke Gasification: Challenges and Future Prospects