US1126077A - Rotary drier. - Google Patents

Description

W. E. PRINDLE.

ROTARY- DRIER.

APPLICATION FILED AUG. 6, 1913.

Patented 5241.26, 11915.

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ROTARY DRIER. v APPLICATION FILED AUG. e, 191s.

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W. E. PRINDLE.

ROTARY DRIER.

APPLICATION FILED AUG. e, 1913.

Patented Ja11.26, 1915.

3 SHEETS-SHEET 3.

WTLLIAM E. PRINDLE, OF MANITOWOC, WISCONSIN.

ROTARY DRIER.

Application led August 6, 1913.

To all whom t may concern Be it known that I, WILLIAM E. PRINDLE, a citizen of the United States, and residing at Manitowoc, in the county of Manitowoc and State of Wisconsin, have invented cer tain new and useful Improvements in Rotary Driers, of which the following is a full, clear, and exact description.

My invention relates 'to the class of rotary driers; and pertains more particularly to that type of drying apparatus designed foruse in drying pulp, or other material, possessing a large degree of moisture; and relates in an especial sense to an improved interior arrangement for effectively drying material of this general character.

One object of the invention is to provide a novel drier arrangement whereinhighest temperatures are effectively employed to act upon material in its wettest stage, with the application of gradually decreasing temeratures to the material as it correspondingly parts with its moisture, whereby the material is discharged as an uniformly dried product. Another object is the provision in a drier of this character of intercommunicating longitudinal chambers, whereby the heating medium has an extended transverse and free circulation through all of the chambers.

A further object is the provision of an improved means for cascading and stirring up the material, and wherein the degree of cascading and stirring is increased by a particular and novel arrangement of mem bers as the material correspondingly parts with its moisture. A still further object is the provision of means in a rear drier chamber adapted to prevent dry andlight particles from being drawn therefrom by suction means positioned adjacent thereto.

These, together with such other objects as may hereinafter appear, or are incident to my invention, I attain by meansof a construction illustrated inpreferred form, wherein:

Figure 1 is a verticalv longitudinal section through a drier embodying my idea of means;

Figures 2, 3 and 4 are transverse sections taken through the drying portions F, Gr,

Specification of Letters Patent.

outlet 13,.

Patented Jan., 26, 319115.

Serial No. 783,248.

and H on the lines ll-U, III-IH, llV- IV, respectively, and illustrating diagrammatically the preferred interior arrangement in these said portions;

Figure 5 represents a section taken transversely through the expansion or dust chamber D; and,

Eigure 6 is an enlarged showing of Figure 4, ll'lustrating more clearly certain details of construction omitted therein for reasons of lucidity.

In carrying out my invention, llv provide a tubular drier shell A communicating at its feed or front `end with a suitable source of heat, as the furnace chamberI indicated by B, through the stationary connecting me'mber C, about whose peripheral edge 4 the said front end is adapted to rotate. The shell receives rotary movement through the gears 5 and 6, the latter being'connected with any suitable source of power, and is further provided with tires 'l' formed thereon which move on rollers 8, as is usual in driers of this character.

Preferably the shell A is disposed at an inclination to the horizontal, the rear or discharge end being lower than the feed end and rotatably received at 8.a in the front wall of an expansion or dust chamber D,-

which latter incloses the said rear. end. The chamber D communicates with an eX- haust fan E, through an opening 9 'preferably formed in its rear wall, and has mounted therein the staggered baille plates l0, whose purpose will be hereinafter described. The chamber is provided with a' downwardly and centrally inclined base portion or hopper 11, in the lower portion of which a worm conveyor' 12 is mounted to discharge the dried product outwardly through the This conveyer is adapted to be operated by suitable power connections.

A feed member is mounted in the stationarymember, C, such as the feed spout designated by the numeral 14, and is designed to feed the wet pulp, or the like, bn to the helicoidal members l5 which are formed on the inner face of the drier and adjacent to the feed end thereof.I

An effective arrangement of drier interior parts, is the preferred sectional construction shown in the drawings, and wherein I contemplate the provision of three drier sections or portions, represented by the letters F, G and lol, and diagraminatically illustrated in section in Figures 2, 3 and 4. These portions which are disposed in stated order longitudinally within the shell A may be characterized as the front, central, and rear drying sections, respectively.

The arrangement within the front section consists in the provision of partitions 16 which extend inwardly and radiallyV from the shell to form longitudinal compartments, the inner ends of which partitions preferably do not meet, whereby the compartments are capable of having inter-communication with each other through their innerv passages 17. r1`he passages not only permit an effective cascade" of the material within the drier, but in addition thereto provide for a free and extensive circulation of theheatcd air or gases, so that the material in each compartment maybe uniformly dried.

For the purpose of cascading the material as the drier shell rotates, I provide each partition with the lifting blades 18 mounted atl intervals thereon, and which have their outer marginal edges bent or flangedl inwardly toward thc longitudinal axis of the shell as at 19, so that at certain times in the rotary, movement of the drier the lifting blades virtually act as retaining shelves for portions of the material; and as' such are designed to prevent material from moving en masse; tending rather to disintegrate and break up -the mass' in order that the heated air or gases from the furnace chamber act upon the material in an effective and economical manner. rl`he blades 18 may be conformed to decrease in relative width aecordingly as they near the longitudinal center of the drier.

This g stated arrangement of partitions with their retaining shelves not only pertains in an exclusive sense to the front drier section F, but continues rearwardly in the shell A as a basis or necleus for the interior arrangement of the other sections G and H, terminating approximately at the peripheral edge of the latter section. Section G in addition to the said partitions and shelves is provided in each compartment with a central flight or shorter stirring partitionQO having retaining shelves 2.1 of similar' conformation and arrangement to that of the shelves 18.

and the suction induced by the fan.

in each longitudinal compartment, each radially interposed between a partition 16 and a central flight 20 as in the manner indicated in the drawings. These intermediate and shorter flights z2 also carry blades or shelves 23, but which are oppositely disposed in staggered or alternate arrangement with respect to adjacent shelves 18 and 21, and further have their flanged marginal edges bent away from the drier axis to confront the said shelves 18 and 21, and thus occupy a position where they substantially overlap.

At the inner terminals of each longitudinal partition is mounted a flanged dellecting plate 24, coperating therewith and with each other to define the passages 17, and which are adapted to aid in disintegrating the mass as part of it passes through the said passages at predetermined intervals during the rotary movement of the drier.

Referring now more particularly to Figure 6, it will be seen that the several flights are adapted to be maintained rigidly in their intervaled and radial positions bv means of the flanged arcuate brace members Q5 which are secured to them as in the preferred manner shown, and to the partitions 16. 1V hen assembled the braces as a whole are concentric with the drier shell and this arrangement forms a rigid connection which at the same time does not interfere with the drying operation. Furthermore, the inner ends of the several partitions 16 may be braced by rods 9.6, disposed at intervals of say five feet, which may or may not, as desii-ed, be in turn braced longitudinally by the angle irons 27 disposed in the axial line of the drier shell A.

1'1v ith the parts in position as herein described, the operation of the drier may be substantiallyV outlined as follows: The beet pulp, for example, is fed into the front end of the drier as it rotates through the feed spout 11 and is carried a relatively short distance reaiwvardly by the lhelicoidal members 15 to the front drier section F, aided somewhat by the inclination of the drier At this point the pulp contains practically moisture, and is first cascaded in that portion of the drier wherein highest temperatures constantly prevail, inasmuch as the feed end is in communication with the furnace chamber B, as already set forth.

As the material progresses rearwardly itgradually parts with its moisture, and passV ing through the section F enters the central section G where it is subjected to slightly1 lower temperatures, but receives a certain amount of necessary stirring and a more effective cascading by reason of the additional members providcd for that purpose in this section. Similarly, in progressing farther in a rearwardly direction, the pulp,

Which` has parted' 'with the greater 'percentiage of its moisture, reaches the larger rear sectionli, whereinvitis subjected to reduced temperatures but alsofto the maximum degree of stirring and cascading, until it reaches the open rear end 'Where it gravitates onto the conveyer in the@chamber D, by which it is discharged through the outlet 13 as an uniformly dried product.

From the description made, it will be apr.

parent, that the material in its wettest stage is subjected to the highest temperatures, and as it gradually parts with its moisture is acted upon by gradually decreasing temperatures and velocities, and that the extent of stirring and cascading is correspondingly increased as the material get drier. The product on reaching the discharge end of the drier shell is dry and light, and is retained in the chamber by the baiiie members disposed therein to prevent the dried product from being drawn out bythe exhaust member E i 1 Another advantage incident to the provision ofthe expansion chamber-is that the `flow of the gases is retarded, facilitating the deposit of the lighter' particles which ordinarily would be drawn out.

` The entire arrangement is very effective and practical and lends itself to the construction of a durable and reasonably cheap drier. There is an entire absence of 1nvolved and intricate parts, and as the compartments communicate centrally with each other, there is little opportunity for the material to cake and partially clog up the drier. i

I do not intend to restrict myself to the exact arrangement as shown, nor-to the precise details of construction as shown, as it is obvious that variations thereof may be made without departing from the spirit and scope of my vinvention as pointed out in the appended claims.

The essential features, elements and op, eration of the apparatus, together with Vits simplicity and other advantages thereof, Will'be clearly apparent to those skilled in the art.

Having thus described my inventiom-and illustrated its use` what I claim as new and desire to secure by Letters Patent is the following: I

1. In a rotary drier; the combination of a shell, va group of intercommuni'cating segmental compartments adapted to receive the material to be dried comprising a'plurality of radial partitions disposed in said shell toY have their convergent ,inner marginal portions spaced away from each other about the axial line ofthe shell,andlconstructed and arranged with reference 5to eachixother. so asy to provide an unobstructedfpassage Way for the travel of the materialin a transverse direction between adjacent and oppositelyv disposed`frrliemb'ers'- ,ofA the groumfand meansf-forfcascading fthe material 'in its said `Compartments` disposed'. therein "to-'rec`eive the material to be dried comprising radial partitions extending toward the axis of the shell but terminating short thereof in spaced relation to provide an unobstructed passage way adjacent the axial line of the shell, said passage way forming a means of direct communication between` members `of the compartment series for the travel of the material therethrough as the shellrotates, and means disposed in said compartments with reference to said passage way for cascading the material during its travel Vfrom* one compartment to the other.

In an apparatus of the character. de'- scribed,A the combination of y a drier shell communicating with'fa source of heat ad# jacent its front 'end and having a yfeed member, an expansion chamber inclosing the discharge end of the shell, an exhaustl member connected with said chamber, and oppo-I sitely disposed Vbaiile members extending transversely of the chamber and interposedy between the discharge end of the shell and the inlet of the exhaustmember.

4. In a drier, a drier shell communicating at its front end with a source of heat, a feed member at the front` end, means to induce a flow of heated air rearwardly through the shell comprising n expansion chamber and an exhaust mem er connected therewith, said expansion chamber inclosing the open rear end of the shell and provided with a hopper bottom, and a dischargeputlet and a` discharging means mounted in the hopper bottom, and adapted to deliverthe dried material to said dischargeoutlet substantially as described.

5. In an apparatus of the character described, the. combination of a drier shell adapted to receive the material to be dried and to Vcommunicate with a 'source of heat, an exhaust member therefor, an expansion chamber interposed between the exhaust member and the discharge end of the shell, said expansion chamber being provided with a discharge passage and a discharge outlet, and a baille means extending, transversely of the chamber and disposed with reference `to said passagefsubstantially as andfor the purpose set ,-forth.

6. In a drier, the combination of a drier shell adapted to receive the material to be dried and communicating with a sourceof heat, an expansion chamber inclosing" the discharge. end ofA the drier and formed with anexhaust opening, said 'expansion chamber being provided with a longitudinal discharge passage, and a discharge outlet, a

bae means interposed between the dissigned my name in the presence of the two charge end of the drier and the said exsubscribed Witnesses. haust opening and disposed transversely of said passage, and a discharging device lol' WILLIAM E' PRINDLE 5 catedin said discharge passage and adapt- Witnesses:

ed to deliver to said outlet. A. L. NASE:-

In testimony whereof I have hereunto F. J. NASH;

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