Improvements in or relating to the drying of grass or the like

Abstract

Abstract 477,279. Drying grass &c. KALOROIL BURNERS, Ltd., and GOLDBERG, A. June 20, 1936, Nos. 17245 and 26390. [Class 34 (ii)] Grass or a similar crop is dried in two stages, an initial stage in which a batch of the material is partially dried, and a final stage in which the batch is completely dried in a rotary drum by the passage therethrough of hot gases while the material is rotated in the drum, drying in the initial stage being effected by the passage through the material-of hot gases leaving the final stage. In the construction shown in Fig. 1, a rotary drum 3 of gas-pervious material is mounted within a stationary drum 1 provided with an inlet 6 and an outlet 7 for the supply and discharge of heated gases. The outlet leads to a hopper 16 which is divided into two parts by a partition 17 and two hinged perforated sheets 19, 20. Heated air from a furnace is adapted to be supplied to the drum 3 or to be diverted to the hopper by way of a trunk 26. Three flap valves 27, 28, 29 are provided for controlling the flow of the heated gases. With the flaps in the position shown, heated air flows through the drum, and passes through sheet 20, pre-heating the grass in the right-hand side of the hopper. When the grass in the drum is sufficiently dried the valve 27 is operated to close the supply of gas to the drum and divert it through the trunk 26 and perforated sheet 18 to grass in the left-hand side of the hopper. The drum is then emptied, and refilled with pre-heated grass by swinging inwardly the sheet 20. The valve 29 is then moved to cover the sheet 20, the valve 27 is restored to the position shown, and the valve 28 is moved to place trunk 26 in communication with conduit 25 leading to the right-hand portion of the hopper. The gas then flows through the grass in the drum and escapes through the grass in the left-hand portion of the hopper. In a modification an undivided hopper with a base consisting of a pair of co-operating counterweighted hinged flaps of perforated material is provided, the flap valves 27, 28, 29 and associated conduits being dispensed with. In the construction shown in Figs. 3 and 6, two dampers 27a, 27b are connected so that when one is closed the other is open whereby heated air is supplied either through pipe 8 for passage through the rotary drum 3 or through pipe 26 leading to chamber 34. In the latter case the air passes through the perforated base of one or other of two hopper sections 17a, 17b according to the position of a valve 28a operated by a handle 36. The perforated bases are hinged at 37 and are adapted to be raised or lowered by manuallyoperated ropes 38. A perforated cover 41 with rollers 42 may be placed over either of the hopper sections.

Inventors

No inventors recorded.

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