Development of a flooded-bed scrubber for removing coal dust at a longwall mining section

Dust generation resulting from various mining activities, such as excavation, loading, and transportation, is a major health and safety issue in underground longwall mines. This issue has been intensified by the increased production rates associated with modern equipment, technologies, and mining methods. In response to a report by the National Institute for Occupational Safety and Health (NIOSH), showing an increasing trend in Coal Workers' Pneumoconiosis (CWP), the Mine Safety and Health Administration (MSHA) established new dust regulations mandating lower dust concentrations and more frequent dust sampling. This research focuses on the viability of enhancing dust control techniques by integrating a flooded-bed dust scrubber into a longwall shearer. To accomplish this objective, a full-scale physical model of a Joy 7LS longwall shearer, modified to accommodate the scrubber, was designed and fabricated at the University of Kentucky. Subsequently, this mock-up was transported to the longwall test gallery at the NIOSH Pittsburgh Research Laboratory (PRL) for testing. The paper provides a brief description of longwall mining, the operation of a flooded-bed scrubber, and a comprehensive overview of previous attempts at applying scrubbers to longwall shearers. Next, it describes the conceptual design and working principles of the flooded-bed dust scrubber as integrated into the shearer mock-up. The paper concludes with results of shakedown tests, indicating dust reduction from 46% to 53% in the return airways of the test gallery. These promising results demonstrate the potential health and safety benefits of the proposed concept and justify further investigation into its testing, refinement, and application.