Dust creates health and safety issues in mining and there are several different ways to reduce the amount of respirable dust created. Dust particles also affect the operation and efficiency of mining equipment. One device currently used to reduce dust in a coal mine is a flooded-bed dust scrubber. These type of scrubbers are found on continuous miners and are designed to capture dust particles close to the cutting head. However, the fibrous screens on the flooded-bed dust scrubber clog easily reducing both production and the quality and quantity of air miners are exposed too. The flooded-bed dust scrubber was designed in the 1980s and has not seen any significant changes since. A Vortecone is a wet scrubber system designed to capture small particles in the air and can easily replace the flooded-bed dust scrubber system on a continuous miner. The Vortecone was initially developed to capture over-sprayed paint particles and due to the capture ability was converted over into the mining industry. The first design of the Vortecone had two outlets and a large pressure drop across the system. The Vortecone was redesigned to have one outlet in order to increase confinement time of particles and thus increase the capture abilities. Using CFD analysis and laboratory testing, the redesigned Vortecone has been proven to have a lower resistance than the original design as well as the currently used convention screens. The Vortecone also proved to have a high capture efficiency at high airflows. This maintenance-free wet scrubber device requires much less maintenance than a conventional screen and thus can be used continually without interrupting production. The Vortecone has been designed so it can easily be mounted onto a continuous miner in place of the currently used scrubbers.

Heavy industries, such as mining, generate dust in quantities that present an occupational health hazard. Prolonged exposure to the respirable dust has been found to result in many irreversible occupational ailments in thousands of miners. In underground mining applications, a variety of scrubbing systems are used to remove dust near the zones of generation. However, the wire-mesh type fibrous screens in the flooded-bed dust scrubbers used on continuous miners, are prone to clogging due to the accumulation of dust particles. This clogging results in a reduced capture efficiency and a higher exposure to the personnel. This research establishes the Vortecone, an inertial wet scrubber system, as a suitable alternative to the existing filters. The Vortecone accelerates its inlet fluids into a rapid circulatory motion into a vortex chamber, preferentially moving the heavier particles towards the impermeable surface to be trapped by the circulating water film. Vortecones are used on automobile painting lines and capture over-sprayed paint particles with cleaning efficacies exceeding 99 % while requiring only infrequent maintenance. The existing design of the Vortecone could also be altered to control the flow patterns. This dissertation presents detailed computational fluid dynamics (CFD) models to describe air flow patterns in the Vortecone in steady and transient states. Multi-phase spray models were generated to simulate injection of water into the Vortecone. The volume of fraction (VOF) approach was adopted to mimic the air-water interface. The Lagrangian particle tracking method was used to model particle capture on the interface described by the VOF. The CFD models indicate excellent cleaning efficacies, especially of larger particles. Laboratory experiments with optical measurements of aerosols in a reduced scale model of the Vortecone validate the computer models. These experiments which were performed on dust samples with particle sizes 0.3 μm and above, show that the Vortecone captures 90 % particles by mass exceeding about 5.20 and 3.20 μm at air flows of 0.28 m3/s (600 cfm) and 0.38 m3/s (800 cfm), respectively. The development of detailed large eddy simulations (LES) of air flow in the Vortecone provides a novel contribution to research by better resolving the flow patterns. An impactor-type, self-cleaning, non-clogging impingement screen system was designed as a substitute for conventional screens used in continuous miners. The screen could further be used as an efficient dust capturing mechanism with a demister in general mining applications. CFD models and laboratory experiments are presented to establish the cleaning efficacies of the system. Laboratory experiments to investigate the cleaning efficiency of a fibrous-type conventional screen is also discussed. The parameter, filter selection factor, is proposed to compare the performance of the three systems (Vortecone, fibrous screen, and impingement screen) under similar flows. The Vortecone has been found to be the most efficient dust-cleansing system, although it is the most power intensive fillter. The impingement screen shows a similar cleaning efficiency and a much higher availability compared to the conventional fibrous screen. Because of its minimal maintenance requirement, the impingement screen shows significant promise in dust-control applications in mining.