The Role of Dust Curtains in Passive Dust Control

Enhancing Conveyor Efficiency: Optimizing Dust Control with Advanced Curtains

A method for passive dust control involves installing dust curtains near the exit end of the transfer point’s settling zone. Positioned where the belt leaves the transfer point, these rubber curtains act as barriers or baffles that reduce air velocities, allowing airborne dust to settle back onto the belt. The curtains create a "settling zone" that decreases airflow, facilitating dust settlement. Most conveyors benefit from at least two curtains. Some installations, particularly those requiring isolation of dust-collection or suppression systems, may benefit from additional curtains.

1807HThese rubber curtains can be made either as individual curtains as wide as the skirtboard or they can be fabricated to a fraction of the skirtboard width and installed in an alternating or "staggered" arrangement to slow airflow.

The curtains should be made of 60 to 70-durometer elastomer and extend approximately 25 millimeters (1 inch) from the top of the conveyed product pile on the belt. They are installed through the top of the transfer-point enclosure and are often trimmed in the field to match trough angles and material load profiles.

Instead of placing the curtains at the end of the covered chute work, it is better to install them inside the covered skirtboard, 300 to 600 millimeters (12 to 24 inches) from the end of the chute work. The faster the belt speed, the further inside the chute work they should be placed. Placing the final curtain inside the end of the enclosure allows any material particles struck by the curtain to settle back onto the belt. The curtains should be spaced approximately 450 millimeters (18 inches) apart, forming an area where dust can settle or where dust-collection or suppression systems can be applied. The use of dual dust curtains in conjunction with dust suppression systems is a patented technology of The Raring Corporation. If curtains are used to isolate dust suppression and/or dust collection installations, they should ideally be spaced 900 millimeters (36 inches) apart.

When multiple curtains are installed, inner curtains can be solid (un-slit) rubber to enhance their air control capabilities. Only the final or exit curtain needs to be slit to minimize the risk of material being displaced from the belt. The curtains should allow easy access for maintenance of the chute and be easily removable for replacement purposes.