Use of silica sand as a proppant has grown dramatically over the last decade with the rise in production of unconventional resources. Large volumes of silica sand are used as a proppant to hold open formation fractures. The sand is pneumatically conveyed into frac sanders before being moved again into a blender where it is mixed into the fluid to be pumped down hole. During these operations, silica dust enters the air and poses hazards to those working on site. The exposure and inhalation of silica dust can cause silicosis, the most widespread industrial disease in the world. Silicosis has been known of for hundreds of years, traditionally found in workers in the sand blasting, mining and construction industries. While the causes of silicosis are known, the disease is incurable once developed. Furthermore, the disease can take up to 15 years to materialize, making workers currently exposed unaware of the potential dangers they are presently in. According to a recent U.S National Institute for Occupational Safety and Health (NIOSH) study, many frac sites exposure levels exceed, sometimes by a factor of 10, the NIOSH Recommended Exposure Limit (REL) to crystalline silica.
In an effort to combat the increasing exposure to silica dust during fracture operations dust collection equipment has been developed. SPE163528 discussed the development of this equipment and mentions other opportunities for dust mitigation. This equipment has now been deployed to the field. This paper discusses adjustments to the equipment and further realized opportunities for dust mitigation. These include helping avoid problems such as personnel over-filling the sand bins and addressing pneumatic flow rates beyond the design limit of the dust collection system.