Abstract: A cooling tower comprising at its lower portion, beneath an exchange surface, a catch basin receiving the cooled water and having an aperture formed therein, a vertical-axis fan mounted in the aperture being adapted to draw air from beneath the basin and force it upwards through the tower, a conventional water streaming mechanism being provided at the upper portion of the tower.

Abstract: A duct having the shape of a pyramid frustum for the flow of powder in suspension in a carrier gas is of increasing width and decreasing height in the downstream direction. The duct has a solid end-wall and a wall provided with an opening between the open upstream base joined to a supply pipe and a solid portion joined to the open downstream base so as to form a spray-discharge nozzle. The device comprises a screen having holes for the discharge of carrier gas and a grid formed by flat partitions. Inclined deflectors extend transversely within the duct in the vicinity of the opening, the angle of inclination being of increasing value from the upstream end to the downstream end.

Abstract: A ventilation and air conditioning apparatus operating according to the adiabatic evaporation principle and adapted to be fitted under a roof, the apparatus comprising a prismatic housing of which the bottom portion consists of an annular water-filled tank having in its central portion an upstanding frustoconical element having a vertical axis of which the vertex angle is at least 30 degrees. The major base of the element is connected in an air-tight manner to the tank, the minor base of this frustoconical element being disposed at the top and closed, and receives through it the vertical shaft of an electric motor driving a helical fan provided with relatively large blades rotating at a relatively slow speed and adapted to draw in air through a shaft of which at least the lower section is vertical and opens into the upper portion of the housing, while the upper section of this shaft opens into the external atmosphere.

Abstract: An apparatus for the pneumatic conveyance of pulverulent or granular material, has a reservoir for the material, a fluidization barrier in the reservoir, an outlet for material flowing from above the barrier in the reservoir, an inlet conduit for fluidization gas opening below the barrier, a conveyor conduit connected to the outlet, an inlet conduit for pressurized conveying gas opening into the conveyor conduit, a first valve in the inlet conduit for fluidization gas, a second valve in the inlet conduit for conveying gas and control means for the said first and second valves arranged to control both the valves in dependence upon pressure in the conveyor conduit and to maintain said second valve partly open when said first valve is open but to open said second valve beyond a predetermined opening degree when said first valve is completely closed.