Pneumatic tank system for storage and transfer of pulverulent material

Claim 1

A pneumatic storage tank for storing pulverulent material or the like comprising, a tank having a cylindrical side wall and upper and lower dished heads enclosing and sealing opposite ends of the side wall, said tank adapted to be supported in a vertical position; a plurality of slope sheets within said tank, said slope sheets sealed to said cylindrical side wall, about the entire circumference of the side wall, and inclined downwardly from the side wall to the central region of the tank adjacent the lower dished head of the tank; a plurality of air slides within said tank, said air slides disposed along said slope sheets and extending from the cylindrical side wall of the tank and inclinded radially downwardly from the side wall to the central region of the tank adjacent the lower dished head of the tank, wherein said slope sheets and said air slides separate said tank into an upper compartment and a lower compartment; input means for providing pulverulent material or the like into the upper compartment of the tank; discharge means for removing pulverulent material or the like from the upper compartment of the tank; an air manifold positioned in the lower compartment of the tank, said air manifold including means for receiving air from an air source, said air manifold further including air conduit means for providing air directly to said air slides wherein said air conduit means comprises a plurality of air conduits, each air conduit extending from the air manifold to a separate air slide in a closed system such that air does not escape from the air manifold into the lower compartment of the tank external of said air manifold; a filling material disposed in and completely filling the lower compartment of said tank, said filling material surrounding said air manifold, said filling material supporting the slope sheets against pressure build-up in the upper compartment of the tank; and air pressure adjusting means for adjusting air pressure between the air manifold and the upper compartment of the tank, said air pressure adjusting means consisting solely of at least one air pressure diverter valve within the upper compartment of the tank and means for connecting said diverter valve to said air manifold for relieving air pressure in the air manifold when the air manifold air pressure exceeds the air pressure in the upper compartment by a predetermined amount.