Dust Control Handbook for Industrial Minerals Mining and Processing

used successfully to perform this cleaning. Brushes need to be adjusted or replaced oftendue to high wear potential. It is also critical to capture the dust removed from the bagswith an LEV system.Develop and implement a plan for dealing with broken bags that minimizes manualhandling. This can include a vacuuming system or a ventilated waste hopper device.Every effort should be made to eliminate plant personnel from manually handling anybroken bags.Enclose bagging and palletizing areas from the general plant environment through the useof clear plastic stripping. If entry is not necessary, a solid type curtain could be used.These enclosed areas should be under negative pressure through an LEV system toprevent dust from migrating to other areas of the plant.Collect dust at the source through an LEV system rather than trying to redirect or todilute with ventilation fans. The use of free-standing fans only circulates the air and dustand does not remove it from the plant.When using an OASIS, periodically clean and replace filters and ensure that clean filteredair is evenly distributed down over the worker. Significant airflow reductions can occurfrom dust-laden filters.Check and lubricate bearings on LEV systems, including the OASIS, as well as checkpower transmission belts. In addition, consider the use of a pressure differential gauge ormonitor to indicate system problems or when maintenance needs to be performed.Ductwork to the LEV system should be examined and cleaned periodically to ensure thatthe system is working properly. Capture velocities at the face of shrouds and hoodsshould be monitored periodically to ensure proper functioning.REFERENCESCase History [2006a]. Dustless bag filling system puts material in, takes dust out. Powder andBulk Eng 20(5):82–87.Case History [2006b]. Robotic palletizer improves company's bottom line. Powder and BulkEng 20(5):88–93.Cecala AB, Covelli A [1990]. Automation to control silica dust during pallet loading process.In: Proceedings of SME Annual Meeting. Preprint 90–28.Cecala AB, Muldoon T [1986]. Closing the door on dust - dust exposure of bag operator andstackers compared for commercial bag valves. Pit & Quarry 78(11):36–37.Cecala AB, Timko RJ, Prokop AD [1997]. Bag and belt cleaner reduces employee dustexposure. Rock Products 100(3):41–43.Cecala AB, Zimmer JA, Smith B, Viles S [2000]. Improved dust control for bag handlers. RockProducts 103(4):46–49.Constance JA [2004]. Ways to control airborne contaminants in your plant. Powder and BulkEng 18(5):118–119.Bagging 185