Bin Storage Safety Considerations
The safety considerations for the bin storage of powdered or pelleted materials is similar to that for fixed roof tanks. The primary danger in the bins comes from dust in the vapor space above the material creating an explosive or ignitable condition. Ignition sources should be minimized and dust conditions reduced by the use of filters or bag houses. A safety vent or rupture disk should be included to prevent over pressurization in case the filter bags clog during operations. Care should be taken during the design of the bin to reduce horizontal surfaces inside the bin where material can remain and create a hazard when the bin is opened for maintenance; the air above such areas has been known to explode while work inside the bins was being performed during normal repairs. Additionally, the bin can be inerted in a manner similar to that used for atmospheric storage tanks (NFPA 68 and 69). The pneumatic transfer of solids can also be preformed using an inert or a low-oxygen gas with a closed loop return to the sending tank.