GB688276A - Improvements in and relating to the production of viscose rayon threads, fibres, filaments and the like - Google Patents

Abstract

<PICT:0688276/IV (a)/1> Apparatus for the recovery of carbon disulphide from viscose rayon threads comprises a container for a heated liquid, conveying mechanism for passing the thread through the container, a hood-like bell mounted so that its edges can be immersed in the hot liquid in the container, and an outlet from the bell for removing carbon disulphide vapours under their own pressure, wherein the mounting for the conveying mechanism permits the latter to be raised so that the threads can be held temporarily above the normal level of the liquid in the container and the bell is so mounted that with its edges still immersed in the liquid it can be moved laterally to permit such temporary raising of the conveying mechanism. In the example, as shown in a vertical sectional view, a thick tow 1 of viscose rayon filaments is led over a guide roller 2 into a hot liquid 3 in a rectangular container 4. Below the level of the liquid there is a conveying mechanism comprising two groups 5, 6 of three flanged rollers (of which two, viz. 7 and 9, are shown), independently rotatably mounted on holders 10 which are rigid with a shaft 11 so that partial rotation of the shaft by means of lever 12 lifts the groups of rollers 5, 6 clear of the level of the liquid as shown at the positions 9 and 10 behind the bell 17. The tow passes under the first roller 7 of the first group 5 and then backwards and forwards between the rollers of both groups 5, 6 before being drawn out of the liquid through a pair of squeeze rollers 13. The conveying mechanism is duplicated in the tank 4 so that while one end of the tow is being treated with the liquid another end can be threaded up on the duplicate group of rollers 5, 6 which have been lifted clear of the liquid in order to facilitate this operation. A single hood-like gas bell 17 is suspended on wheels 18 above the container 4, so that it can be moved laterally. The edges of the bell 17 dip below the surface of the liquid 3, and the bell completely covers one or other of the conveying mechanisms when the rollers of the groups 5, 6 of the covered conveying mechanism are in their lowered operating positions. Carbon disulphide released by the tow and trapped by the bell passes out from the latter to a cooling plant (not shown) through a central pipe 19, projecting vertically upwards from the centre of the container 4 and opening into the gas space within the bell. When changing over to the duplicate conveying mechanism, the bell is pushed over to the opposite side of the container 4, the opening of the pipe 19 always remaining enclosed by the bell. The temperature of the liquid is maintained at 90-95 DEG C. by means of a steam pipe 20 passing through the container 4. Specifications 170,817, [Class 32[, and 509,981 are referred to.ALSO:<PICT:0688276/IV (c)/1> Apparatus for the recovery of carbon disulphide from viscose rayon threads comprises a container for a heated liquid, conveying mechanism for passing the thread through the container, a hood-like bell mounted so that its edges can be immersed in the hot liquid in the container, and an outlet from the bell for removing carbon disulphide vapours under their own pressure, wherein the mounting for the conveying mechanism permits the latter to be raised so that the threads can be held temporarily above the normal level of the liquid in the container and the bell is so mounted that with its edges still immersed in the liquid it can be moved laterally to permit such temporary raising of the conveying mechanism. In the example, as shown in a vertical sectional view, a thick tow 1 of viscose rayon filaments is led over a guide roller 2 into a hot liquid 3 in a rectangular container 4. Below the level of the liquid there is a conveying mechanism comprising two groups 5, 6 of three flanged rollers (of which two, viz. 7 and 9, are shown) independently rotatably mounted on holders 10 which are rigid with a shaft 11 so that partial rotation of the shaft by means of lever 12 lifts the groups of rollers 5, 6 clear of the level of the liquid as shown at the positions 9 and 10 behind the bell 17. The tow passes under the first roller 7 of the first group 5 and then backwards and forwards between the rollers of both groups 5, 6 before being drawn out of the liquid through a pair of squeeze rollers 13. The conveying mechanism is duplicated in the tank 4 so that while one end of the tow is being treated with the liquid another end can be threaded up on the duplicate group of rollers 5, 6 which have been lifted clear of the liquid in order to facilitate this operation. A single hood-like gas bell 17 is suspended on wheels 18 above the container 4, so that it can be moved laterally. The edges of the bell 17 dip below the surface of the liquid 3, and the bell completely covers one or other of the conveying mechanisms when the rollers of the groups 5, 6 of the covered conveying mechanism are in their lowered operating positions. Carbon disulphide released by the tow and trapped by the bell passes out from the latter to a cooling plant (not shown) through a central pipe 19, projecting vertically upwards from the centre of the container 4 and opening into the space within the bell. When changing over to the duplicate conveying mechanism, the bell is pushed over to the opposite side of the container 4, the opening of the pipe 19 always remaining enclosed by the bell. The temperature of the liquid is maintained at 90-95 DEG C. by means of a steam pipe 20 passing through the container 4. Specifications 170,817, [Class 32], and 509,981 are referred to.