水气转化对超临界水煤气化的抑制特性

Water-gas shift reaction (WGSR) is a key homogeneous reaction in the supercritical water gasification (SCWG) of coal, but the impact of the WGSR on the heterogeneous reaction of coal in the particle pores remains unclear. The mechanism of intrapore water-gas shift reaction on the SCWG of irregular-shaped coal particles was investigated through three-dimensional numerical simulation. It is revealed that the intrapore WGSR consumed a significant amount of supercritical water intended for the heterogeneous reaction of coal, inhibiting the gasification rate. Additionally, a large amount of CO₂ was generated and accumulated in the particle pores, reducing the diffusion coefficient of the supercritical water. An effective gasification factor was introduced to quantitatively characterize the inhibition by the intrapore WGSR, showing that the inhibition effect increased with the particle size. The increased gasification time of the coal particle due to the inhibition was found to have a simple logarithmic relationship with the effective gasification factor.