Abstract: A pneumatic conveyance tobacco dryer which includes a conveyance duct having a first portion, a second, upwardly extending portion and a third, curved portion intercommunicating the first and second portions. A tobacco feed chute extends downwardly and opens into the second portion of the duct. The geometry of the dryer at and in the region of the feed chute is such as to effect the object of reducing the contact of tobacco particles with the inner surfaces of the conveyance duct.

Abstract: In a drying process for increasing the filling power of tobacco material, the cut and moistened tobacco material is conveyed in a drying gas flow, dried within a tubular drying section and subsequently separated from the drying gas. The drying gas has at a feed point into the drying section a temperature of at least 200.degree. C. and a flow velocity of at least 30 m/sec. The flow velocity of the drying gas is reduced in the drying section. The flow velocity of the drying gas at the charge point into the drying section is at the most 100 m/sec. Within the drying section, to reduce the local heat transfer coefficient and the local mass transfer coefficient between the surface of the tobacco material and the surrounding drying gas, along with the reduction of the flow velocity of the drying gas, the flow velocity of the tobacco material is also reduced. At the end of the drying section the drying gas has a flow velocity of at the most 15 m/sec and a temperature of at the most 130.degree. C.

Abstract: A separator for separating tobacco particles from a tobacco/gas mixture comprises a hood, a circular deflection space disposed in the hood, an inlet for the tobacco/gas mixture to be separated opening tangentially into the circular deflection space, a downwardly directed outlet in the deflection space for the tobacco particles, an outlet for the tobacco particles at the lower end of the hood, and an outlet for the gas above the deflection space. The deflection space is formed by an upwardly closed and downwardly open cylinder; the gas is withdrawn from the hood above the deflection space; the size ratio of the area of the deflection space to the area of the inlet lies between 5 and 30; and the size ratio of the area of the hood to the area of the inlet is greater than 50.

Abstract: Comminuted tobacco material expanding apparatus which includes a cellular wheel feeder and an expansion chamber integrated in the cellular wheel feeder. A nozzle opening in a wall of the expansion chamber provides for the introduction of a mixture of air and stream for accelerating the tobacco material under a pressure drop to at least 50 m/s with a residence time of the tobacco material in the expansion chamber of less than about 1/10 s. At least one nozzle opening is located in an end wall of the expansion chamber near the bottom so that an adjustable stream/air mixture moves the tobacco material substantially at a right-angle out of the expansion chamber. The expansion chamber is connected to an acceleration tube with converging cross-section which is connected to a delay tube.

Abstract: For the moistening of comminuted, more particularly overdried, smoking materials, the requisite quantity of water is applied in at least two spraying sections situated one in succession to the other, in which the water is divided into tiny droplets by means of ultrasonic atomizers. Cooling sections are arranged between the individual spraying sections.

Abstract: A device for determining the concentration of condensable vapor in a flowing gas stream which includes a gas evacuation conduit for receiving a sample of gas from the stream, a gas condenser in the evacuation conduit for condensing out essentially all of the condensable vapors in the sample and a gas flowmeter connected to the gas discharge of the gas condenser for determining the flow of the dry gas sample exiting the condenser. A pump is provided for withdrawing a sample of gas from the flowing gas stream and for conveying this sample at a constant, known volumetric flow through conduit and to the gas condenser and the flowmeter and a control means operatively connected to the flowmeter determines the condensable vapor concentration by comparing the flow of the dry gas sample with the known volumetric flow fed to the condenser.