Modeling atomization, gasification, slag deposition in a novel top-mounted gasifier with dual-swirling multi-nozzles

Entrained-flow gasification technology has become a key approach for improving energy efficiency in industrial applications. Nevertheless, the conventional single-nozzle configuration commonly employed in existing entrained-flow gasifiers restricts feedstock throughput and poses challenges for the scale-up of coal gasification. To overcome these limitations, this study introduces a novel top-mounted swirling multi-nozzle gasifier, incorporating counter-rotating dual swirlers in the secondary nozzles. The proposed design optimizes the internal flow field by exploiting the interaction between swirling flows and jets. This study investigates the atomization characteristics of the novel atomizing nozzle and conducts a comparative analysis with conventional single-nozzle gasifiers, with emphasis on temperature distribution, flow dynamics, particle behavior, and wall slagging tendencies. The results indicate that the three-channel swirling nozzle improves atomization efficiency and spray angle regulation through the dynamic coupling of counter-rotating flow fields. Compared with traditional single-nozzle gasifiers, the top-mounted swirling multi-nozzle configuration generates an enlarged recirculation zone, which enhances gas–solid mixing, extends particle residence time, and significantly improves gasification efficiency. The reverse swirling flow also facilitates a more uniform dispersion of coal–water slurry droplets, thereby reducing thermal deviations within the gasifier. In addition, the multi-nozzle arrangement allows simultaneous processing of multiple feedstock slurries. Overall, this study presents a novel gasifier design, elucidates its operating mechanism, and provides theoretical guidance for the structural design and optimization of boilers in energy conversion systems.