US2076415A - Apparatus for the drying of paper or fabrics - Google Patents

Description

April 6, 1937. F. w. PARTSCH ,4

APPARATUS FOR THE DRYING OF PAPER OR FABRICS 4 Sheets-Sheet 1 q INVENTOR BYCK Filed April 19, 1935 @mgv vg ATTORNEY April 6, 1937. F CH 2,076,415

APPARATUS FOR THE DRYING OF PAPEROR FABRICS Filed April 19, 1935 4 Sheets-Sheet 2 I .INVENTOR ZWM-q ATTORNEY April 6, 1937. F. w. PARTSCH v APPARATUS FOR THE DRYING OF PAPER OR FABRICS Filed April 19, 1935 4 Sheets-Sheet 3 INVENTOR 7;; /k%@ ATTORNEY April 6, 1937. F. w. PARTscH 2,076,415

APPARATUS FOR THE DRYING OF PAPER OR FABRICS Filed April 19, 1955 I 4 Shets-Sheet 4 INVENTOR M k/ZzZ I BY 4 WM 6; ATTORNEY if I Patented Apr. 6, 1937 ETD APPARATUS FQR THE DRYING 9F PAPER. 0R FRIIQS Frank w. Partsch, Jackson Heights, N. Y., as-

signor to ii. 0.

Engineering Corporation,

New York, N. 331., a corporation of New York Application April 19, 1935, Serial No. 17,161

5 Cia This invention relates to a method and apparatus for the drying of paper or fabrics with the requirements usually encountered in the drying of sized and impregnated papers.

In the drying of sized and impregnated papers, certain difiiculties occur. It is advantageous to control and vary the temperature and humidity in different parts of the cycle of drying while at the same time motivating the paper through the dryer without injury to the traveling web of paper. For efiiciency and high quality of product the application of the drying medium with respect 'to the surface of the web is also of great importance.

There should not be a drying in spots but there should be a uniform drying of the web, both transversely and longitudinally. Ordinarily, temperatures as high as possible should be maintained in order to reduce the time element, length of dryer, and increase the speed of drying, but these temperatures must be controlled within certain limits as there are certain critical temperatures that should not be exceeded for quality products, and these critical temperatures may and often are different in different parts of the cycle of drying. The dryer should be sufficiently flexible so that variation in temperature and humidity can be controlled independently in different sections of the dryer whereby the drying of the material takes place under most conditions from the interior outward of the paper. Under certain conditions, dependent on the type of surface that may be desired in the product however it may be necessary to first dry the surface relatively quickly and then more slowly remove the moisture from within. In a dryer adapted to sized and impregnated papers, it is advantageous if the dryer may be so regulated with temperature and humidity so as to produce either of the two methods of drying to produce in the same dryer at different times the different types of surfaces of product desired. The rate of drying as well as the relative rate of drying the interior as compared to drying the surface is to a large extent dependent upon the temperature of the drying medium, the humidity of the drying medium, the velocity of travel of the drying medium on the surface of the material being dried, the degree of impingement of the drying medium, the movement of the material being dried, and the movement of the moist film that forms on the surface of the goods.

One of the objects of this invention is to provide a dryer especially adapted for the drying of sized and impregnated paper but which would also be used when drying other materials where the same requirements aremet as in the drying of sized and impregnated paper.

A second object of this invention is to provide a dryer consisting of units whereby the apparatus and principles of this invention 'may be applied independently in the various sections to get the proper conditions in the various parts of the cycle of drying, and also that they may be varied in connection with the various types, thicknesses, kinds and forms of paper impregnations or coat ings.

Still another object of the invention is to provide a dryer or dryer system which can be controlled either manually or by automatic control with respect to either the temperature or humidlty, or both, either in a fixed relationship to each other or an entirely independent control as required by the material to be dried.

A still further object of the invention is to provide means whereby the air supplied is provided alternately from the front and back of the dryer so as to make still more uniform the distribution of the'air to the web to eliminate the possibilities of uneven drying transversely.

A still further object of the" invention is to provide air nozzles which may be rotatedto direct the impingement of the air supply at a different angle to the web of material, or to direct it to another portion" of the web in order to avoid the formation of wrinkles and like objectionable features.

A still further object of the invention is to control the volume and velocity of the air so that more or less may be discharged to either side of the web, or'to either edge of the web.

A still further object of the invention is to provide a dryer or dryer system consisting of sections whereby the recirculated air may be taken from one section and after mixing with the required fresh air and properly treating the air supply of then supplying this air to an adjoining sec tion or, to meet certain requirements of the product desired, to take the air from one section, mix with the required fresh air properly treated and supply it to the same section.

Referring to the drawings:

Figure 1 is a view partly in elevation and partly in section of a. dryer embodying the principles of my invention.

Figure 2 is a plan view of Figure 1.

Figure 3 is a. cross sectional view of Figure 1 along the line 3, 3, looking in the direction of the arrows.

Figure 4 is a sectional view of a modified form of the device. 1

Figure is a plan view'of a modified form of nozzle arrangement.

Figure 6 is a modified form similar to Figure'l. -Figure 7 is a view in elevation of a rotatable 5 nozzle. In carrying out my invention, I propose to utilize a dryer formed of sections A, B, C, D,

etc., which sections are surrounded by a housing or chamber l. Within the housing or chamber l, I provide carrier rolls 2 about which are carried the sized or impregnated web of paper 3 whereby the web is formed into loops and motivated through the dryer. At the top -of each section A, B, C, D, etc., I provide headers 4, 4, from which nozzles 5, 5, protrude alternately, that is, a nozzle 5 protrudes from header 4, then a nozzle 5' protrudes from header 4', etc. The using of alternate nozzles connected to opposite headers for their air supply gives a more even distribution. -In addition, the individual nozzles are tapered to secure a uniform emission of heating medium from each orifice. The carrier rolls 2 are driven in any well known manner. At the top of each section A, B, C, D, etc., are similar headers 6, 6, also carrying nozzles I, I, These.

nozzles are similar to nozzles 5, 5', in arrangement. The nozzles 5, 5', from the top headers 4, 4, cause the heating medium to impinge or wipe one side of the web while the bottom nozzles I, 1', cause the heating medium to impinge or wipe the other side of the web 3. The nozzles are rotatable being journaled in the headers. A slot 3| and set screw 32 can be utilized for locking them in the desired position or any other well known locking device may be used. It is desirable to change the angle of impingement to prevent the formation of wrinkles and to procure the most satisfactory and efflcient drying effect. The angle with which the air should strike the moving web depends on the class of goods'and the wiping efiect desired and distribution of the heating medium. Dampers 8, 8, 9, 9', control the distribution so that it is possible to vary the distribution frgm the header to the nozzles individually whereby some of the loops of web 3 may not receive any air and otherloops may receive much air. These individual orifices are of such shape and design that they are adapted to be stopped or V have deflectors 38 whereby the distribution of air throughout the length of the nozzle, or in other words, over the width of the sheet, may be controlled. The deflection or stopping of the orifices [0 permits the dryer to be used for different widths of goods, and permits controlling of the drying effect on the edges, and varying the volume and velocity of the drying medium emitted from the open orifices.

The apparatus is designed to control the vol- 0 time and velocity of the air heating medium in its discharge upon either side of the sheet,this being controlled by controlling the volume and velocity to the alternate nozzles, and the volume and velocity from the alternate nozzles by said deflectors or stops.

The drying medium is suppliedto headers 4 by conduits II and headers 4' are supplied with drying medium through conduits ll. Conduits II, II, lead from the discharge of a fan or blower l2. Dampers l3, I3, control the quantity of heating medium delivered to headers 4, 4', and are located in conduits II, II, respectively. Conduits H, II, also supply headers 6, 6'. Dampers l4, l4, likewise control the volume to headers 6. 6. Dam er I5 is a distribution The nozzles 5 and I have orifices l8.

with recirculated air thence through filter 33 and heater l8 to fan or blower l2. From fan l2 the mixture is recirculated through conduits II, II, distributing the heating medium to headers 4, 4', 6, 6', which in turn feed nozzles 5, 5, l, 1', completing the cycle. The nozzles 5, 5', l, I, are tapered to secure a uniform emission of heating medium from each orifice l0. There is a nozzle for each loop of the travelling web whereby the heating medium impinges on both sides of the web. The openings to the mixing chamber H, to wit, I9 and 20, have dampers I9, 20', and automatic damper controls and are conjointly operated to proportion the air admitted through the openings. If desired, the dampers may be manually operated. The fresh or room air may be filtered before admission to mixing chamber I! as shown. The dampers I9, 20', when automatically operated are done so through the cus-.-

tomary humidistats 2| and pneumatic control systems whereby the humidity may function to control the dampers. This is shown by humidistat 2| operating damper motor 22 which operates dampers l9', 20', through well known linkage. The temperature of the heating medium is controlled by thermostat 23 through pneumatic means 24 to operate steam valve 25. It is understood that although steam has been shown as a means for heating the heating medium, any well known form of heating device may be used. The dual control of the temperature and humidity preferably operates independently although it may be arranged to operate conjointly, if desired. It is also desirable that valve 25 be of such design that it may be also operated manually as well.

This may be required for repairs or to shut off a particularheater of one section permitting the other sections to operate. In order to prevent too high a moisture content of the recirculated gases and to prevent the building up of too great a plenum pressure, Ipropose to provide a vent or stack 26 to relieve the atmosphere in housing or chamber l I also provide a damper 21 which is preferably automatically controlled by a thermostat 21' but may be manually operated.

. In the modified form shown in Figure 4 instead of alternate nozzles from headers 4, 4, .6, 6, the headers may be joined by pipes forming nozzles 28 with the same orifices as the heretofore described nozzles. These pipes or nozzles 28 may also be rotatable (as shown in Figure 7) to direct the streams of heating medium issuing from the orifices ID in the desired direction. The orifices in pipes or nozzles 28, may also be stopped or deflected similarly as were nozzles 5,

5', I, I. In other respects, this modification is where variable temperature and humidity control throughout the length of the dryer may not be required, the number of automatic control instruments may be reduced to one set or more as necessary. In other words, the method and apparatus is subject to variation permitting its use over a wide field in connection with drying in the paper industry and adapting itself not only to new installation but to the conversion of some types of dryers that are at present in use. An illustration of the variation is Figure 5 wherein the nozzles 34 from the top header 5' run in opposite direction from the bottom nozzles 35 connected to bottom header 6. In the next section the nozzles are reversed in direction, that is the.

top nozzles 34 are connected to header 4 and the bottom nozzles 35 are connected to header 6. The remaining sections also alternate in the change of direction of the nozzles. That is, each alternate section has the nozzles extending in opposite directions thereby the distribution'of the heating medium is more even than would be the case were they all extending in the same directions.

In the modified form shown in Figure 6 by means of conduit 36 connecting the recirculation ducts IS, the recirculated air may be taken from one section and recirculated through an adjacent section. In other words, the recirculated air is taken from one section and after mixing with the required fresh air'and properly treated the air supply is then supplied as heating medium to an adjoining section. The heating medium is thus primarily taken in at one end, circulated through that section, withdrawn from that section, properly treated to the desired temperature and humidity, supplied to the next section as a drying medium, removed from that section, again properly treated to produce the desired temperature and humidity and then supplied to the adjoining section as a drying medium supply and this is continued until the section at the end farthest from the fresh air supply at which point the drying medium may be vented and discharged to atmosphere. This method of heating medium circulation is in a cycle progressing with the direction of travel of the goods and permits of the maintenance of heating medium supply in an efiective condition for the maximum and desired results. Obviously, the direction of travel of the material being dried may be changed, if desired, to a countercurrent method by reversing the direction of the material through the dryer.

With my invention, not only is there a control of the temperature throughout the dryer but there is also a continuous rehabilitation of the drying medium so that it is controlled effectively with respectto humidity, temperature, admission of fresh air, removal of dust, and a closer maintenance of the required conditions throughout the length of the dryer.

In Figure 6, I have shown the admission of the fresh air through a filter 31 into a fresh air conduit 38 with leads to the respective stations A,

B, C, D, etc., and into the mixing chambers I'I. With this arrangement, the air may be filtered prior to the admission to the mixing chambers.

As the wastage when a break occurs in the drying of paper causes considerable loss, the

proper drying of the web becomes important from this angle alone. The web when wet, or dried in spots, is easily torn or injured and unless properly dried is unsatisfactory in quality. The combined moisture in the paper should not be entirely removed for if the paper is dried to such an extent that all the moisture is removed'it becomes generally brittle. It, therefore, is preferable to not only control the temperature, but- 1. A drier for a web material comprising a.

chamber, a set of parallel rollers adjacent the top of said chamber, a second set of parallel rollers adjacent the bottom of said chamber, said rollers being arranged to support a web in a series of loops, a set of nozzles substantially parallel to and arranged above said first 'set of rollers, a second set of nozzles substantially parallel to and arranged below said secondset of rollers, each nozzle being provided with a longitudinal row of discharge ports for supplying air to said web and each nozzle being rotatable about its longitudinal axis to vary the angle of impingement of the air upon said web and means for supplying heated air to said nozzles.

2. A drier according to claim 1 in which said nozzles are tapered and means are provided vfor controlling emission throughout. the length of each nozzle.

3. A drier according to claim 1 in which said air supplying means'comprises a mixing chamber, a heater, a fan, a recirculating conduit from the drying chamber to said mixing chamber, a fresh air inlet to said mixing chamber, and conduits FRANK W. PARTSCH.

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