GB275546A - Low temperature distillation furnace - Google Patents

Abstract

275,546. Plassmann, J. Aug. 5, 1926, [Convention date]. Retort furnaces; charging and discharging. - Comprises modifications in detail in the low temperature distillation apparatus described in Specification 240,800 in which annular carbonizing chambers 14 and heating-spaces 4 alternate in a structure having a fixed portion and a rotary portion, one carrying the charging and discharging apparatus, and the other forming the cham. bers 14 &c. In the apparatus shown in Figs. 1 and 3, in which the outer casing carrying the charging &c. apparatus rotates, the heating-gases are supplied through a central conduit 1 and are distributed evenly by a baffle 2 to the heating- spaces 4, and pass thence through symmetrically disposed shafts 5 to an annular outlet flue 6. The walls between the shafts 5 and the inlet passages 3 are heat insulated. Two or more feed shafts 11 for the material are spaced equidistantly round the apparatus and are supplied with fuel bv screws 10 from a central bunker 9 fed by an elevator 8. In each of these shafts is fitted a stirring device 12 for loosening the material. The discharging-scrapers 15 are either formed integrally with the casing of the feed screws 13, or are attached thereto by bolts 32, and these parts, and also the closing bands 30 for the carbonizing- chambers, are mounted so that they are free to move vertically relatively to the outer casing, and can thus accommodate themselves to movements due to differential expansion of the fixed and moving parts of the structure. The coke is discharged into shafts 16 and falls on to a conveyer 18, by which it is taken to a discharge, opening 19 closed by a rotary valve 20. In this valve the coke is sprayed by a sprinkler 21, and any water which is not evaporated is collected in the false bottom 23, so that when the valve is rotated the water is again passed over the coke. Water may be sprayed over the valve to prevent leakage of air into the apparatus. In the construction shown in Fig. 5, in which the inner part rotates in a fixed outer casing, a labyrinth packing 47 is provided between the fixed and moving parts of the conduit 1, and a sand seal 46 containing a loose ring 4 is similarly fitted in relation to the outlet flue. The fixed casing is carried on supports 43 so that free access can be, obtained to the driving-gear 45. The diameter of the flue space is enlarged around the packing 47 so that the cross-sectional area for the passage of heating-gases is not restricted. The upper part of the rotary structure is supported by a roller bearing 49, which allows free upward expansion. Any dust which settles in the lower part of the apparatus is removed by scrapers 41, and the coke is discharged on to a jigging conveyer 51. The exhausted heating-gases are passed through a reheater and returned to the apparatus. The Specification as open to inspection under Sect. 91 (3) (a) states that the feeding or discharging devices, or both, may be mounted so that they can be withdrawn from the carbonizing. chambers. This statement does not appear in the Specification as accepted.