US2539947A - Apparatus for the continuous aftertreatment of flocculent textiles - Google Patents

Description

Jan. 30, 1951 B. G. DE KLERK 2,539,947

APPARATUS FOR THE CONTINUOUS AFTERTREA'I'MENT 0F FLOCCULENT TEXTILES Filed Feb. 6, 1947 N grwwwto'n o 2 Sheets-Sheet l Jan. 30, 1951 B. G. DE KLERK 2,539,947

APPARATUS FOR THE CONTINUOUS AFTERTREA'I'MENT 0F FLOCCULENT TEXTILES 2 Sheets-Sheet 2 Filed Feb. 6, 1947 Patented Jan. 30, 1951' APPARATUS For;

THE CONTINUOUS AFTER- TREATMENT OF FLOCCULEN T TEXTILES human Gijsbertus de Klerk, Arnhem, Netherlands, assignor to A'merican Enka Corporation, En'ka, N. (2., a corporationof Delaware Application February 6, 1947, Serial No. 728,896

' In the Netherlands March 27, 1946 4 Claims. (cl. 08-22) This invention relates to apparatus for the liquid treatment of flocculent textiles.

In the liquid treatment of flocculent textiles it is known to spread out the textile material on a conveyer or the like and to spray liquids on succeeding portions thereof in order to wash, deacidify, desulphurize, bleach, tone up or otherwise treat the material; These operations are normally conducted in open rooms within the operating plant where the atmosphere of the entire room isexposed to the gases which may be evolved during the treatment process and where the chemicals used in the treating process are exposed to air. By way of example, one form of continuous procedure for. the treatment of fiocculent textiles which conforms to the general description set forth above is shown in British Patent 332,003.

The known procedures for continuous treat-, ment of flocculent textiles, while generally satisfactory, are subject to the limitation that, where the treating media required are sensitive to o'xyen, or where the gases to be used in or evolved from the treatment reactions are either costly or poisonous, the exposed, open plant continuous method cannot be employed.

It is therefore an object of the present invention to provide apparatus for the continuous liquid treatment of flocculent textiles which is, characterized by the isolation of the treatment zone from'the surrounding atmosphere of the plant whereby the escape of dangerous or valuable gases is prevented while the treatment zone isprotected from the effects of'atmospheric air.

It is a further object of this invention to attain the foregoing objects by a simple but eifective process and by the use of inexpensive and easily constructed apparatus.

Other objects and advantages of this invention will be apparent from the following detailed description of one of its forms in conjunction with the annexed drawings wherein:

Figure 1 is a view in side elevation of a machine for the continuous treatment of flocculent textile material in a closed zone;

Figure 2 is a view in section taken on the line 2-2 of Figure 1; and

Figure 3 is a fragmentary perspective view of a portion of the apparatus used for propelling. the flocculent material'through the machine.

In the drawings the reference numerals I and 2 represent the conveying elements for conveying the fleece of flocculent material '3 to, through, and from the liquid treatment zones. The'elements I and 2 are arranged in alternating groups to define a fleece supporting grid, as may be seen 2 in Figure 2. The elements I and 2 are bars, the bars I being stationary and defining the path of the material through the machine and the alternating bars 2 being mounted for eccentric oscillatory movement to propel the fleece through the machine, the eccentric rollers 4, 5, 5 and I serving todrive the bars 2. The use of the bars I and 2 to define a grid forthe propulsion of the material and the mode of driving the bars 2 is shown in British Patent No. 332,003 and hence forms no part of this invention.

According to this invention the bars I and 2 between the rollers 4 and 5 and again between the rollers 6 and l are bent to define depressions at 8 and 9 in the material path and these depressions are deeply immersed in sealing liquids I0 and H disposed in tanks I2 and I3 respectively which constitute an integral part of the liquid treatment machine. Also immersed in the sealing liquid-are the lower edges of front and rearlwalls' I4 and I 5 of a closed treatment chamber 6.

Since the textile material supported on thement chamber I5 through sealing liquids in and II, it is necessary to prevent floating of the material. This is accomplished by the use of rollers I1 and I8 located respectively in tanks I2 and I3, the rollers being supported on guide pins l9 and 20 respectively, the ends of which ride in slots 2I and 22 provided in the side walls of the tanks I2 and I3. By this expedient floating of the textile material in the sealing zones is prevented and the fibrous fieece is compressed and forced onto the bent portions of the grid at 8 and 9. The bars 2 in the upward slopes in tanks I2 and I3 are provided with teeth 23 extending obliquely upward in the direction of material propulsion, see Figure 3.

, Pressing rollers 24, 25, 28 and 21 are associated with eccentric rollers 4, 5, 6 and 1 respectively, the rollers 24, 25, 2'6 and 21 being provided with axially extending pins 28, 29, 30 and 3| which ride in slots 32, 33, 34 and 35 provided in suitable standards, not shown, which are located on both sides of the machine. The rollers 24, 25, 25 and 21 serve to press out liquids entrained by the textile material:

The top 36 of the treatment chamber I6 is provided with two removable covers 3] and 38 having therein observation windows 39 and 40. The removable covers 31 and 38 are mounted in seals H and 42 respectively so that the treatment chamber may be maintained leakproof even in the event of the maintenance of a pressure below atmospheric therein.

Within the chamber l6 there are located containers 43, 44 and 45 adapted to spray or distribute treating liquids on the fiocculent material being passed thereunder. The containers 43, 44 and 45 are fed from feed pipes 46, 41 and 48 which pass through the top wall 36 of chamber l6 in a gas-tight, manner.

The liquids sprayed from the containers 44 and 45 are collected in container 49 and through conduit 58 are led to container i. From container 5| the liquids are recirculated through conduit 52 by operation of pump 53. Conduit 52 is branched at a point just above cover plate 36 to feed selectively either or both of containers 44 and 45 through conduits 41 and 48, the control being effected by valves 54 and 55.

The washing liquid sprayed from container 43 within the chamber I6 is recovered in tank l2 and another washing liquid supplied through a pipe 56 to a spray container 51 located outside of the chamber I6 is recovered in tank l3.

It will be noted that the level of the sealing liquid is maintained by overflow standpipes 58 and 59 located in tanks I2 and I3 respectively.

The spraying vessels 43, 44, 45 and 51 may be connected in series, if desired, so as to make it possible to transfer'certain quantities of liquid from the spraying system comprised of container 51 and tank l3 to the system comprised of container 43 and tank l2 and from there to the system including containers 44 and 45 and tank 49. This arrangement is of practical value where the sealing liquids l8 and II are merely dilutions of the actual treating liquid sprayed from the containers 44 and 45.

It will be noted that the container 5| is provided with a cover 68 having an observation window 6| therein, the cover 68 being mounted in seals similar to those described in connection with covers 31 and 38. Furthermore, a gas evacuation pipe 62 is provided which connects the tank 5| to the top 36 of the chamber l6 through a valve 63.

Also for gas control there is provided a valved pipe 64 passing through the cover 36 of the treatment chamber l6.

The manner in which the process is conducted is partly apparent from the foregoing description. The flocculent textile material 3, which may have been subjected to a pretreatment before the treatment now to be described, is spread out on the grid defined by the bar elements I and 2 and is delivered by operation of the bar elements 2 in the direction of the arrow in Figure l. The material is fed between rollers 4 and 24 onto the first bent grid and slides down into the sealing liquid III, the material being held down, compressed and forced into the grid at this point by the roller I 1. The material then passes to the rising part of the grid, to the right of depression 8 in Figure 1, whereon its upward movement is regulatedand insured by teeth on the bars 2, as is shown in Figure 3. By action of the roller 25, the

sealing liquid entrained by the material from the tank I2 is in large measure pressed out so that, according to the position of the partition between tanks i2 and 49, it may escape partially or com pletely into one or the other of these vessels. The fleece is then propelled over the horizontal central grid within the container I6 between the rollers 25 and 26 and is there sprayed from above with treating liquids from the spray containers 44 and 45. This liquid is collected after passage through the fleece in the collecting vessel or tank 48, the pressing out action of the roller 26 as- 4 sisting in the recovery of the treating liquid. The pressed out fleece is then passed through the liquid seal II and conveyed further in the direction of the arrow.

The treating liquid recovered in the tank 49 is passed through pipe 58 into a lower collecting and storing vessel 5| from which it is delivered by pump 53 for reuse in the manner heretofore described. The collecting vessel 5| is closed except for the gas pipe 62 which connects it to the treatment chamber i6. The gas pipe 62 functions to lead gas entrained by the sprayin liquid back to treatment chamber l6.

Where the treating liquids, the fleece or the reaction between the treating liquids and fleece may be deleteriously effected by the presence of oxygen, inert gas may be introduced into the chamber l6 through valved conduit 64.

The process and apparatus described above favor the performance of a number of important textile operations which are otherwise dimcult to control.

Example I Staple fiber which is produced from viscose'by a known process wherein the freshly spun masses which are coagulated but have not yet been decomposed to form cellulose hydrate may be advantageously treated in accordance with the present invention. The cut fibers are decomposed with diluted acids or with dilute solutions of acids and salts, so that most of the poisonous hydrogen sulphide is developed not on the spinning machine, but during the subsequent decomposition. According to the present invention the unstretched fibers are decomposed by spraying with a decomposing medium and a remarkably durable curled fiber is formed. The process and apparatus of the present invention are suitable for carrying out this decomposition continuously and for deacidifying the xanthogenate fiber cuttings and for collecting the evolved hydrogen sulphide in concentrated form. To this end the cut fibers are sprayed in the treatment chamber with the cold decomposing medium and the hydrogen sulphide containing gases are sucked out of the chamber under a low negative pressure (gauge) through the conduit 64. The first liquid seal in the container I2 is fed with substantially acid-free, but sufliciently concentrated, salt solutions such as 50 sodium sulphate or other spinning salts in order to prevent liquefaction of the xanthogenate yarns and premature decomposition thereof. The second liquid seal in the container or tank l3 may consist of a dilute salt-and-acid solution, such as is naturally formed when water is sprayed onto the fibrous fleece onto which acid and salt have adhered.

Example [I In the production of staple fiber from viscose, freshly spun and cut cellulose hydrate fibers contain, in addition to salts, acids and other impurities, a large percentage of the carbon disulphide which was employed in the production of the viscose. This carbon disulphide is customarily eliminated from the fibrous masses by washing with hot water. According to the process and apparatus of the present invention, carbon disulphide in the form of an almost undiluted vapour may be continuously eliminated from the cellulose fibers by spraying the textile material in the chamber IS with hot water, for example, from 80 to 90 C. The carbon disulphide may then be withdrawn from the chamber through the 75 conduit 64 and subjected to reconditioning or regeneration. In this case the liquid seals are maintained with cold water. The elimination oi the carbon disulphide from the loose fibers by spay-,- ing with hot water or with a diluted hot spinning ,bath, produces a marked curling oi the fibers in addition to the volatilization oi the carbon disulphide from the interior or the yarn.

The methods described in Examples 1 and 2 may be combined by treating the cut xanthogenate fibers with highly heated decomposing medium which is sprayed in the chamber It. In this case the hydrogen sulphide and the carbon disulphide are simultaneously evolved and can be withdrawn together through conduit 64. The combined treatment afiords advantages in the elimination of a treatment chamber and further intensification of the fiber curl is eflected. On the other hand, the combined methods entail increased expense in separating the Jointly recovered hydrogen sulphide and the carbon disulphide for separate regeneration.

Example III Protein fiber such as casein wool, particularly after it has been treated with nitrate solutions, as taught in-German Patents Nos. 692,232 and 702,001, has an unpleasant yellow discoloration which is due partly to oxidation but mostly to diazotisation. The discoloration withstands normal reducing and bleaching agents such as sulphur dioxide, sodium thiosulphate, hydrogen peroxide and the like. However, it can be completely removed by treatment with a dilute solution of sodium hydrosulphite (N52S204). This substance. while excellent in removing the discoloration from protein fibers, is especially sensitive to oxygen in aqueous solutions, and immediately decomposes, for example, as when heated to 45 0., with sulphur separation by oxidation. This sensitivity is increased when the sodium hydrosulphite a substantially oxygen-free atmosphere is maintained within the container l6.

By operation in accordance with the present invention losses due to oxidation of sodium hydrosulphite are maintained at a low level, despite the fact that the water seals are by no means free of dissolved hydrosulphite resulting from splashing of the liquid and entrainment by the textile material. It has been found that the liquid seal has a relatively steady level and therefore a small surface absorbs relatively little oxygen as compared with a spraying liquid which would offer a large surface to oxygen due to its distribution in the form of drops. Hence, during treatments with sodium hydrosulphite the containers I2 and I3 are filled and the fiow from spraying vessels 43 and 51 is cut off. While the liquid seals are effective when water is used, their eflectiveness is considerably increased if strong ,gas volume in the chamber.

minimum, that nitrogen or other inert gases of low oxygen content may be introduced into the chamber in sumcient extent to prevent the establishment of too high a pressure difi'erential between the interior of chamber I8 and atmosphere, it being apparent that a high pressure differential might break the liquid seals.

It has been suggested, particularly in the spraying of textiles, that the spraying liquid withdrawn from the collecting vessels carries large amounts of gas with it, which tends to reduce the For purposes of economy where the gases are valuable and, in any event to maintain an adequate pressure within thedchamber It, the gas recycling conduit-l2 is use What is claimed is:

1. Apparatus for treating fiocculent textiles which comprises a treatment chamber including top, side and end walls, a tank underlying each end wall, a wall extending between said tanks and forming therewith a bottom to said chamber, each tank extending above the lower edge of the respective end wallso that a pool of liquid in each tank can function to seal ingress and egress openings to the tank, a conveyor to support and 'conveya. quantity of fiocculent material to and through said tanks under said end walls and through said chamber, said conveyor extending generally horizontally in a plane above the lower edges of the end walls of the chamber within the chamber and to and from said tanks but extending below said edges of the end walls of the chamber within the tanks, and means for applying a treatin liquid to said material during its passage through said chamber.

2. Apparatus for treating fiocculent textiles which comprises a treatment chamber including top, side and end walls, a tank underlying each end wall and extending above the lower edge of the. respective end wall so that a pool of liquid in each tank can function to seal ingress and egress openings to the tank, a conveyor to support and convey a quantity of the fiocculent material to and through said tanks under said end walls and through said chamber, said conveyor extending generally horizontally in a plane above the lower edges of the end walls of the chamber within the chamber and to and from said tanks but extending below said edges of the end walls of the chamber within the tanks, and means for spraying a plurality of treating liquids on said material during its passage through said chamber, means following a spraying means in the direction of conveyance of the material for pressing the treating liquid from the fiocculent material, a collecting trough extending between said tanks and functioning as a bottom wall to the chamber and to recover the treating liquid pressed out of said material and means for returning the recovered liquid to said spraying means.

3. Apparatus as claimed in claim 2 further comprising means for withdrawing or supplying gas to said treatment chamber.

4. Apparatus as claimed in claim 2 in which the means for returning the recovered liquid includes a liquid recovery tank and which further comprises a conduit extending from the top of said liquid recovery tank to the top of said treatment chamber to function as a gas return line between said tank and the treatment chamber.

BAS'I'IAAN GIJSBERTUS DE KLERK.

(References on following page) QEFERENCES CITED tollowing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Sargezit May 19, 1891 Peltzer June 4, 1901 .Peltzer Julie 4, 1901 Shuman se t. 22, 1908 Gungerlch Oct. 4, 1910 Number Number Name Datev Hebden Feb. 11, 1913 Petzold Apr. 8, 1913 Matter Dec. 19, 1916 Silver Sept. 16, 1930 Hetzer May 26, 1936 Davis Nov. 10, 1942 Tegetmeyer Dec. 22, 1942 FOREIGN PATENTS Country Date Great Britain July 17, 1930

Images