A mining researcher at Southern Illinois University Carbondale (SIUC) is leading an effort to reduce the huge amounts of dust created by the large machines miners use to chew coal from the veins beneath the ground. Yoginder “Paul” Chugh, PhD, professor in the department of mining and mineral resources in the College of Engineering, is perfecting a dust control system for retrofitting on continuous coal mining machines. Using water spray technology and strategic placement of the spray nozzles to create “curtains” around dust clouds, Chugh’s team is making huge improvements in dust control efforts at several mines. Traditionally, continuous mining machines have relied on spraying water to control dust, Chugh says. His modified system adds more sprayers, using specific pressures and droplet sizes in strategic areas to knock down far more airborne dust. “We have added more lines of dust control defense and are seeing up to 50% reduction in the dust problem,” he says.<\/p>\n
Wetting coal dust makes it heavier and takes it out of the air. This happens at a very small scale, with tiny droplets of water colliding with tiny dust particles. Often, however, the dust and water fail to come into contact or the water fails to adhere to the dust particle. Chugh’s system improves on this concept by not only wetting the dust but also using the spray to create a sort of water curtain that seals the dust at the face of the machine, away from the operator. The spray also pushes the fine dust near the roof back into the water spray area, increasing its “residence time” in that area and thereby giving it a better chance to contact water and drop out of the air. The system uses this hydraulic spray seal technology to form a curtain from the roof of the mine down, greatly reducing dust rollback. The curtain’s design forms a kind of “window” for the machine operator to clearly see the cutting drum’s work, while additional nozzles around the center of the cutting drum and coal pan at the front of the machine wet the coal further before it enters the conveyer system, cutting down further on dust.<\/p>\n
At least two mines — Viper in central Illinois and Sunrise Mining Co. near Terre Haute, IN — are using the systems, while other mines are testing it. Chugh is working with SIUC’s Technology Transfer Program to license and market the technology. he hopes to market the system as both an after-market add-on to existing machines and a standard item on newly manufactured equipment.<\/p>\n