Water-soluble substances like hydrogen fluoride, generated in semiconductor manufacturing, pose serious health and environmental risks, underscoring the need for effective capture devices. Vertical liquid capture devices help by aggregating and discharging hazardous substances with water, but their design can lead to backflow during abnormal operations, causing unintended releases and impacting efficiency and safety. This study seeks to improve a vertical liquid collection device’s containment performance by optimizing its geometry. The vertical wall was rotated at various angles and directions, and turbulent kinetic energy and streamline distribution were analyzed to assess vortex formation and flow characteristics. These structural modifications identify optimal conditions to control hazardous substance migration, offering insights for future pollutant removal device designs.