For Joe Tabor the real goal behind pursuing graduate research is to protect lives and make working conditions safer.
Virginia Tech mining engineering graduate students appreciate the autonomy that comes with taking on research projects and advanced studies. Yet for many, the real goal behind pursuing challenging research is to improve miner health and safety. That’s true for Joe Tabor, a second year graduate student pursuing his M.S. degree in mining engineering.
Joe is working with Dr. Emily Sarver, department Associate Professor, on research aimed at mitigating diesel particulate matter (DPM) exposures in underground mines. The work is funded by CDC/NIOSH and includes as co-PI a mechanical engineering professor from Clemson University, John R. Saylor, who also serves as a co-advisor for some of the student researchers like Joe.
Diesel engines are common in underground mining operations, providing power for all sorts of needs – from large mining equipment like loaders and haul trucks, to pumps for mine dewatering. However, exposure to engine emissions, including the DPM or soot, can present occupational health hazards for miners. “Over time, high levels of DPM have been reduced through a variety of means such as cleaner burning engines, exhaust after-treatments, or through better mine ventilation,” explains Joe Tabor, a native of Damascus, Virginia.
But in some cases, the available controls are not enough or not practical to implement. “The project I’m working on aims to develop a new approach for reducing DPM, effectively using tiny water droplets to scavenge these nanoparticles from the engine exhaust. For my part, I’m constructing and testing the feasibility of a fogging scrubber.”
“Because DPMs are so small—in the order of 10-200 nanometers—they can remain in the air for a long period of time. However, if the DPMs are captured by the much larger fog droplets, they fall out of the air in a matter of minutes with the droplets, making them an effective means for capturing DPMs.”
The scrubber Joe has helped to develop works in a two-step process. First, DPM is captured by the fog through a process called Brownian coagulation. In the second step, the DPM-laden droplets fall out of the air due to gravitational settling. “Because DPM is so small—on the order of 10-200 nanometers—it can remain in the air for a long period of time. However, if the DPM can be captured by the much larger fog droplets – more like 5 micrometers in size – it has the chance to fall out of the air relatively quickly.”
Joe’s initial efforts centered on design and construction of the field-scale scrubber device, which was based on earlier laboratory and analytical work by Lucas Mendoza and Zack Henderson, two other MS students that worked with Dr. Sarver on this project. Joe’s design had to be practical as well as rugged for on-site conditions. Next, he needed to test the capture process in the field. “For field testing, I basically attach a long tube to an engine tailpipe, and inject fog the near the entrance. By taking particle concentration measurements upstream of the fog and at the tube outlet, I can determine how effective the fogging treatment is at removing DPM, which in turn gives more insight into real world applications for such a treatment.”
“We’re trying to make mining more feasible, more sustainable and to address the human element. It feels good to be part of something you really care about and can be passionate about.”
As an undergrad, Joe found he was particularly interested in the health and safety, and environmental aspects of the mining industry, and he found himself wanting to know more. After earning his B.S. degree from the department in 2018, he turned to graduate school, which gave him deeper insight into the topics he cared about and an opportunity to participate in critical research projects with Dr. Sarver.
“What I like the most about grad school at Virginia tech is that it gives me a chance to really specialize in something I care about,” expresses Joe, who appreciates the autonomy in managing his time, studies, and work. “I’m not necessarily on my own, though,” he says, “I get a lot of help from my advisor. But it’s up to me to make important decisions and find solutions.”