Abstract: A vertical discharge duct provided on a storage vessel wall terminates either in a separate duct outlet or in the vessel outlet at the lower end of the discharge hopper. A duct-clearing carriage is displaceable vertically along the entire length of the duct and the lower end of the duct has an extension which serves as a housing for the carriage when it is not in use. The carriage is equipped with a rotary device for disaggregating the stored material in order to clear the duct in the event of clogging. Disaggregating devices can also be installed within the vessel and within the discharge hopper.

Abstract: A first bottom discharge opening provided at the lower end of a storage vessel and fitted with a shut-off valve is adjacent to a second bottom discharge opening fitted with a shut-off valve. The second opening is joined to an emptying tube which extends vertically within the vessel and has a top orifice located at a level between 1/4 and 3/4 of the total height of the vessel. At the time of final emptying of the lower portion of the vessel through the first discharge opening, the curve of overpressures resulting from the emptying operation is close to the curve of static pressures generated by all the material stored within the vessel when this latter is full. Thus there is no need for any wall reinforcement and construction costs are appreciably reduced.