Multiphase CFD modeling and laboratory testing of a Vortecone for mining and industrial dust scrubbing applications

Abstract

Dust exposure-related occupation diseases are irreversible and have led to debilitating outcomes in personnel. Particles like coal dust generated in mines and accumulated above a critical concentration are explosive. Fibrous type multi-layered filters are the primary dust particle capturing element in flooded-bed dust scrubbers. However, these filters get clogged due to prolonged dust accumulation. This paper investigates the interaction of dust, water, and airflow in CFD in a non-clogging Vortecone filter. The Vortecone accelerates the particle-laden fluid, forces it into rapid swirling fluid motion, and pushes particles to separate and capture them. Filter capture performance in several air and water quantities regimes with aerosol particles exceeding 2.0 μm from a coal-dust laden airstream is described here. Detailed computational fluid dynamics models mimicking steady-state flow regime and transient-state air-water interface motion are presented. Particle tracking and their capture on water film using volume of fraction approach to determine the cleaning efficiency for different particle sizes is presented. Experimental cleaning efficiency results obtained from iso-kinetic sampling and optical particle counting agree with the computer models. Laboratory tests run on the Vortecone showed coal-dust cleaning efficiency exceeding 75% for particles 2.8 μm in size and 90% for 4.7 μm for all airflows.