Effects of the Surface Wettability and Particle Size Distribution of Petroleum Coke on the Stability of Petroleum Coke–Water Slurry

This study explores the effects of surface wettability and particle size distribution on the stability of petroleum coke–water slurry (PCWS). Significant differences in stability were observed among slurries prepared from four types of petroleum coke. Notably, reduced surface wettability was found to enhance slurry stability. The average particle size of all petroleum coke powders was consistently maintained at 23 ± 5 μm, with their size distributions well fitted by the Rosin–Rammler equation. The model parameter n, ranging from 0.60 to 0.84, indicates a relatively uniform particle size distribution, suggesting improved packing efficiency within the slurry. As a result, PCWSs with particle size distributions falling within this optimal range exhibited markedly higher stability than those outside it. The novelty of this study lies in the combined quantitative investigation of two fundamental physicochemical factors—surface wettability (via contact angle) and particle size distribution (via Rosin–Rammler model parameters)—and their synergistic influence on the static stability of PCWS.