US1884727A - Rotary drum drier - Google Patents

Description

Oct. 25, 1932.

M. J. KERMER Ro'TARY DRUM DRIER Filed 001;. 30, 1930 Patented Oct. 25, 1932 a. UNITED STATES PATENT OFFICE MARTIN J'. KERHEB, SNYDEB, NEW

YORK, ASSIGNOB. T0 BUI'FALO FOUNDRY MACHINE COMPANY, OF BUFFALO, NEW YORK, A CORPORATION OF NEW YORK BOTAB'Y DRUK DBIEB Application filed October 30, 1930. Serill No. 492,157.

This invention relates to a rotary drier of the type in which the material to be dried is deposited in a thin film on the periphery of an internally heated drum and then scraped ofi' the drum preparatory to being used.

In machines of this character as heretofore constructed the heatin medium such as steam has usually been admltted at one end of the drum at the center thereof and the water of 1,0 condensation was scooped from the inner side of the wall of the drum. This steam heretofore was not distributed or circulated uniformly over the entire inner surface of thel drum nor did this steam move with any appreciable speed but instead Was virtually stavnant so that the maximum heating efiect of the steam and the maximum output of the machine was not obtained.

It is the object of this invention to provide baffie means for the interior of the drum which will produce a better circulation and distribution of the steam over the entire inner side of the drum and also increase the speed of the steam so as to increase the heat transference to the drum and the drying effect of the same accordingly.

In the accompanying drawing F igure 1 is a horizontal section of a rotary drum drier embodying one form of my invention.

F igure 2 is a Vertical transverse section of the same taken. on line 2-2 of Figure 1.

Figure 3 is a fragmentary longitudinal section showing a drying drum provided With a modified form of my invention.

In the following description similar characters of reference indicate like parts in the several figures of the drawing.

Referring to Figures 1 and 2 the numeral 10 represents the main frame of the machine which ma be of any suitable construction to support tlle working parts.

On this frame the means are mounted whereby the liquid material is dried which means in the present case include two hollow drums having their axes arranged parallel and horizontal and provided with cylindrical bodies 11, 11 which have their opposing sides spaced close together but still far enough apart by a gap to permit thin films of which is journaled in a bearlng 17 on the frame.

These drums are turned in unison so that the opposing sides of their cylindrical bodies move downwardly, this being accomplished in the present instance by intermeshing gear Wheels 18, 19 connected respectively with the Companion trunnions 14,' and aV driving pulley 20 mounted on one of the trunnions and adapted to receive a driving belt. Each of these drums is internally heated so that the film of liquid deposited on the exterior thereof will be dried and as this dried film passes upwardly on the laterally outer side of the drum the same is removed therefrom by a scraper or knife 21 preparatory to receivlng another fresh coat of wet film.

The heating device for each drum includes a supply pipe 22 for the heating medium such as steam which extends lengthwise through the trunnion 16 of the respective drum from the exterior to the interior thereof and terminat-es at its inner end adjacent to the head 12 at the opposite end of the drum. The outer end of the steam pipe 22 is connected by a rotary pipe coupling 23 with the adjacent tubular trunnion 16 so that the latter can turn while the steam pipe remains stationary.

The steam issuing from the inner end of the steam supply pipe heats the cylindrical body or wall of the drum and causes the film of material deposited thereon to dry. As the steam condenses the water of condensation descends to the lowermost part of the drum and from this place the same is picked up by a scoop 24 having its inlet 25 arranged close to the inner side of the cylindrical wall of the drum adjacent to the head 13 and having its outlet 26 communicating With the inner I in from the time the end of the tubular trunnion 16 and connected thereto so asfto turn therewith.

In the absence of any rovision to revent it a considerable part o the steam orms a core in the central part of the drum and does not act promptly on the cylindrical wall of the drum and therefore re uces the efliclency of the machine. Some steam issuing. from the supply pipe 22 at one end thereof 1s also liable to pass directly through the shortest path from the inner end of the steam plpe at one end of the drum to the inlet 25 of the condensate scoop at the other end of the drum thereby losing some of the heating effect and sacrificing some of the capacity of the machine.

In order to obtain the maximum efliciency of the steam and increase the output of the machine means are provided which causes the steam to be held close to the cylindrical wall of the drum and away from axial zone theresteam enters the drum until it has condensed, thereby utilizing the steam more efliciently and economically.

Satisfactory means for accomplishing this purpose include a bafile having a tubular conical body 27 which is arranged lengthwise within the drum and terminates at its opposite ends short of the heads of the drum, the small end of the baile body being arranged adj acent to the inner end of the steam supply pipe and the large end thereof arranged adlacent to the inlet of the condensate removing scoop, thereby forming an annular space between the inner side of the cylindrical wall of the drum and the conical body of the baflie which' is comparatively large in area adjacent to the steam inlet and gradually reduces in area toward the condensate Outlet.

At its small end the baflle body is closed by a head 28 which has a central collar 29 turning on the adjacent inner part of the steam pipe and opposite a large end of this baflle ody is open. Any suitable means may be employed for holding the bafile in its central position within the drum, for example brackets 30, 31 connecting the small and large ends of the baflle with the adjacent parts of the drum.

As thesteam issues from the inner end of the steam pipe the same is deflected radially away from the axis of the drum by the baflle to the inner Vside of the cylindrical wall of the drum and then passes lengthwise through the annular passage between the baflie body and the drum cylinder to the Outlet of the latter at the opposite end of the same whereby the steam acts promptly and efliciently on the drum instead of lying idle to a large degree in the form of a core in the center of the drum.

By making the baflle body of conical form the annular space between the baflle and the cylindrical wall of the drum permits the steam upon issuing from the pipe 22 to expand fully due to the available space within the respective end of the drum being largest, and as the volume of steam gradually decreases in passing from the steam inlet of the drum to the condensate outlet thereof due to progressive condensation of the steam the latter is nevertheless held close to the cylindrical wall of the drum to the conical form of the baflle which causes the annular space between the baflie and drum to decrease in area toward the condensate outlet in the same measure as the volume of steam decreases. No idle steam is, therefore, present in the drum but instead all the steam is compelled to give up its heat promptly and completely thus utilizing the steam to better advantage and increasing the drying capacity of the machine.

This invention can be embodied in forms other than that shown in Figures 1 and 2. For example, as shown in Figure 3 the steam may be supplied to the drum adjacent to the small end of the baflle by a steam pipe 32 passing through the trunnion 33 on the adjacent end of the drum which trunnion is made hollow for this purpose. f.

The advantage of the present improvement consists in using a bafiie arrangement which compels all the steam entering the drum to pass along the inner surface of the latter, thereby insuring a greater heat transfer and a greater drying capacity per unit of surface, without afiecting the thermal eficiency of the machine. In either case it requires approximately one pound of steam to evaporate one pound of water but the baflie plate arrangement such as shown in this application will result in increased dryin capacity.

Moreover, in the old method 0% introducing the steam, the same was merel blown in the drum and no Velocity of any l ind resulted from this action. By introducing the baflie into the drum the steam passes over the inner surface of the same with a considerable Velocity which can be controlled by the clearance between the drum and the baifle and thereby increase the speed of the heat transference and increase the drying capacity of the machine accordingly.

I claim as my invention 1. A drier comprising a horizontal ro-- tary hollow drum which is adapted to receive on its periphery the material which is to'be dried, means for introducing steam into the interior of the drum at one end thereof, means for discharging the condensate from the drum at the opposite end thereof, and a horizontal conical baflle arranged lengthwise within the drum and spaced from the inner side thereof and forming an annular passage for the steam of comparatively large area adjacent to the inlet and of gr'adually reduced area toward the vcondensate discharging means.

2. A drier comprising a horizontal rotary end `adjacen`t"to the condensate discharging,

hollow dru'r' which is adapted to receive on its 'periphery the material which is to be dried, meansfor introducin steam into the interior of the drum at one en thereof, means for discharging the condensate from the drum at th e opposite end thereof, and a horizontal comcal tubular bafile arranged lengthwise within the drum and spaced from the side thereof by an annular passage and having its small end adjacent'to the steam inlet and its large means. -3. 'A drler comprismg a honzontal rota hollow drying drum turning about a honzontal axis and adapted to receive on its ex-` terior the material to be dried and provided at its opposite ends with trunnions which are journaled on a frame and one of said trunnions being tubular and forming an outlet for the condensate from the interior of the drum a conde'nsate scoop mounted on the drum and having its inlet arranged close to the inner side of the peripheral wall of saidv drum, a

steam supply pipe extending through said tubular trunnion and terminating adj acent to the opposite end of said drum, and a baflie of conical'tubul'ar form arranged horizontally and lengthwise within the drum and having its small end arranged'adjacent to the inner' end of said steam suppl pipe and connected therewith by a head while its large end is arranged adjacent to said condensate scoop.

In testimony whereof I hereby aflix my signature.

MARTIN J. KERMER.

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