US2156643A

US2156643A - Digester apparatus

Info

Publication number: US2156643A
Application number: US19369A
Authority: US
Inventors: William H Shipman
Original assignee: Babcock and Wilcox Co
Current assignee: Babcock and Wilcox Co
Priority date: 1935-05-02
Filing date: 1935-05-02
Publication date: 1939-05-02
Anticipated expiration: 1956-05-02

Description

May 2, 1939.

w. H. SHIPMAN 2,156,643

DIGESTER APPARATUS I Filed May 2, 1935 2 Sheets-Sheet l INVENTOR. William H. Shipman ATTORNEY.

May 2, 1939. w. H. SHIPMAN DIGESTER APPARATUS Filed May 2, 1935 2 Sheets-Sheet 2 Patented May 2, 1939 I UNITED STATES PATENT OFFICE.

2,156,643 mons'rsa APPARATUS Application May 2, 1935, Serial No. 19,369

14 Claims.

This invention relates to material handling apparatus and it is more particularly concerned with chemical apparatus for handling fluids. It is exemplified herein in connection with a digester A for the preparation of wood pulp. V

To effectively maintain digester reactions incident to the breaking down'of wood chips to form pulp, a hot liquor of a pre-determined chemical constituency is circulated through the digester, in modern high capacity units. To complete the chemical reactions in the digester in a minimum of time, it is important that effective control of pressure and temperature be maintained, along with the control of the volume of liquor circulated. The apparatus for maintaining such control includes a fluid pressure relief line and a pressure control connection with the upper part of the -digester. This invention ispartlcularly directed to improvements in this type of apparatus.

Even when the relief line connections are at the very top of the digester the relief fluid often carries such a high percentage of solids that pumps and other apparatus handling the fluid might quickly be rendered inoperative.- To prevent this a screen is provided for the relief line, and it is a desideratum that the screen be located within the digester or the digester nozzle. In the present instance, the screen is readily detachable and of such construction that it can be easily 30 cleaned. Furthermore, when the screen lsremoved for cleaning a relief line outlet chamber is entirely exposed so that it may be readily cleaned.. The invention contemplates also a involve the detachment or attachment of the relief line connection with the digester.

The invention also contemplates a digester construction which guides and maintains a rotary chip distributor and permits that distributor to 40 be quickly and accurately positioned within the screen and within the charging port of the di- The invention contemplates a rotary chip distributor which imparts a lateral force to the chips and causes such an arrangement of the chips in the digester that the cooking operations are enhanced and a better quality of pulp thus assured. It contemplates a chip distributor having a rotary impeller located below the relief line screen, and

screen structure, the removal of which does not the digester showing the rotary chip distributor as it is used when the digester is being charged.

Fig. 2 is a partial perspective view showing the top of the digester, the trolley frame for carrying the chip distributor, and the automatic relief valve and piping connecting it to the nozzle of the digester. 1

Fig. 3 is a vertical section showing the screen structure and the chip distributor spider guide on a larger scale.

Fig. 4 is a view looking downwardly from the plane indicated on the line 4-4 of Fig. 3.

The digester structure shown in Fig. 1 of the drawings includes a metallic shell l0 supporting a flanged collar I! at the neck of the digester. Within the collar I2 is a sleeve construction l4 recessed to provide the space l6 which becomes a part of the relief fluid screen chamber. This sleeve has a flange I8 which rests upon the top of the collar l2 and maintains the sleeve in operative position.

The lower end of the sleeve l4 extends within the digester to a point substantially beyond the shell II) where its inner end 20 is belied. This promotes anchoring of the lining 22 around the charging port of the digester.

The drawings also show the sleeve l4 as forming guideways for the arms 24 of'a distributor spider. As illustrated, and more particularly shown in Fig. 3 of the drawings, these guideways are provided by

ribs

26 and 28 integral with the metal of the sleeve.

At the lower end of each 'guideway there is a seat for a distributor spider arm. Each seat is indicated in Fig. 3 as having an inclined face 30 corresponding to a similar'inclined surface on eachspider arm. Each guideway is closed off at its lower end by the material of the sleeve which forms a shoulder 32. The chip distributing apparatus is thereby correctly centered and adequately maintained in operative position within the charging port of the digester.

The sleeve 14 is preferably formed so as to correspond with the configuration of the collar l2, and it communicates at one side of the digester with a relief pipe 34 which is shown extending through the collar l2. This relief pipe in turn communicates with the space I6 which is closed of! by the sleeve and the screen 36 to form a relief line chamber extendingaround the perimeter of the charging port. The screen 3!? preferably rests upon the shoulder 38 at the lower end of the recessed portion of the collar l2, and its inside diameter is preferably identical with that of the inside diameter of the lower portion of the sleeve. The screen is preferably formed of metal with upper and lower outwardly extending

flanges

40 and 42 respectively. The lower of these flanges is shown seated on the shoulder 38 while the upper flange l0 closes off the top of the space which forms the relief line screen chamber.

The screen or strainer 36 is provided on itsinner surface with ribs forming upright guideways which are continuations of the guideways between the

ribs

26 and 28 of the sleeve l4. As shown, the

upper parts

44 and 46 of these ribs are upwardly divergent so as to facilitate the entering and placement of the chip distributor in operative position. Their

lower ends

48 and 58 are shown parallel to each other and parallel to the axis of the charging port of the digester.

80 The chip distributor which is, during the distributor element or, impeller, 52 securedto' the lower end of an upright shaft 54 journaled in a bearing 58 preferably integral with the spider arms 24. The upper end of the shaft 54 is connected by means of ,a universal joint 51 and the telescoping shaft construction 58 to a second universal joint 88. This last universal joint is also connected to the end of an upright intermediate shaft 82 rotatably mounted in. a journal 6 supported by a carriage 66. The shaft 82 is connected by means of

bevel gears

68 and 18 with a driving shaft 12 which is shown coaxial with the shaft ll of the motor 18.

The motor 18 may he also connected to a belt and pulley device 18 so that it may rotate the hopper 88 through the transmission 82 and a belt 84 extending around the grooved wheel 86 rigid with the hopper. The hopper may rotate on rollers 80 which are mounted upon horizontal axes and may be guided by rollers 82 which are rotatable upon vertical axes.

In the operation of the chip distributor the chips are delivered to the hopper 84 in a steady stream and are evenlyv spread by the rotating hopper 88 before they fall through chute 98 and thence through the charging port of the digester. As they pass downwardly from the charging port they are engaged by the impeller 52 and evenly distributed over the digester so as to avoid undesirable stratifications.

The motor as well as the rotating hopper 88 and all of the superposed mechanism may be carried by a frame I08 which is a part of the carriage movable along a trackway from one digester to another.' After the digester is fully charged, the carriage I08 is moved along the track, the telescoping shaft mechanism automatically disconnecting the shaft 54. Thereafter the distributor element may be freely elevated from its illustrated position, the chute 98 removed, and the cover I04 for the digester placed in position so that the cooking operation can begin.

Fig. 2 shows the relief pipe 34 connected to the automatic relief valve I88 at one end and to a digester coupling at the other end. This coupling includes a flanged and threaded nipple I08 telescoped within an exterior nipple II. A coupling ring I I2 presses the gasket Ill against the latter nipple to tightly maintain the assembled parts in their operative positions.

Whereas the invention has been described with reference to the particular apparatus shown in the drawings it is not limited to all the limits thereof, but is of a scope commensurate with the sub-joined claims.

What isclaimed is:

1. Apparatus of the class described comprising, in combination, a digester, a material distributor temporarily insertible through a charging opening in the top of the digester, a structure framing the opening and formed to provide seats for the distributor, means on said structure forming guides leading to said seats, and an annular strainer having guideways formed thereon as continuations of the above mentioned guides.

24 In combination, a digester having arecessed nozzle, a chip distributor, a relief line strainer .ring'seated within the nozzle recess, and means on said ring for guiding the distributor into its operative position.

3. In combination, a digester having a recessed charging nozzle, a channel-shaped screen seated within the recess and cooperating with the walls thereof to form a relief fluid chamber, a relief line extending through the side of the nozzle and communicating with the chamber, a chip distributor adapted to be temporarily seated and operated within the nozzle, a spider extending across the nozzle and supporting the distributor, aligned guideways formed by parts on the nozzle and the screen for guiding the ends of the spider into operative position. and stops formed in the nozzle at the lower ends of the guideways.

4. In a digester, an exterior metal casing formed with a charging opening at the top, a nozzle defining the opening, a flanged sleeve construction extending through the frame and the opening to a position within the casing with the flange of the sleeve resting'upon the top of the nozzle so that the sleeve is thereby supported in its operative position, a digester fluid relief line extending through the side of the nozzle and communicating with a recess formed in the upper part of the sleeve, a digester lining closely fitting around the inner ends of the sleeve and secured to the casing, and an easily detachable metallic strainer ring disposed within the recess and combining with the walls thereof-to form a relief fluid chamber communicating with the relief line.

5. In combination, a digester having a charging nozzle at'the top thereof, a recessed and flanged from the top of the digester, a metallic strainer ring cooperating with an annular recess in the collar for forming an annular fluid relief chamber, a distributor spider, and guideways formed on the collar and the strainer for guiding the spider into its operative position.

'7. Apparatus of the class described comprising, in combination, a digester, a material distributor insertible temporarily through the digester nozzle, a structure framing the opening and formed to provide seats for the distributor, said structure forming guideways leading to said seats and an annular strainer having guideways formed thereon as continuations of the above mentioned guides, means for discharging a stream of chips through the nozzle so that they contact with the distributor, and means for rotating the distributor.

8. In combination, a digester formed with a recessed nozzle, a chip distributor, a relief line strainer ring seated within the nozzle recess, and aligned means on said ring and the nozzle for guiding the distributor into its operative position.

9. In combination, a digester having a metallic shell, an acid proof lining within the shell, a flanged collar extending through a nozzle at the top of the digester and having a lining contacting flange at its inner end, the collar being supported from the top of the digester, a metallic strainer ring cooperating with an annular recess in the collar for forming an annular fluid relief chamber, a distributor spider, and aligning ribs formed on the collar and the strainer for guiding the spider into its operative position.

10. In combination, a digester formed with a charging opening the walls of which present an annular recess, a distributor, distributor supports, a readily detachable sheet metal strainer ring seated within the recess and forming with the walls thereof an annular relief line chamber, and means on said ring for guiding the distributor toward its operative position on said supports.

11. In combination, a digester formed with an opening which is bounded by a recessed frame, a channel shaped strainer seated within the recess and cooperating with the walls thereof to form a fluid chamber, a relief line extending through the frame and communicating with the chamber, a

material distributor adapted to be temporarily seated and operated within the opening, a distributor support extending across the opening, aligned guideways formed by parts of the frame and the screen for guiding the ends of thesupport into operative position, and seats formed in the frame at the ends of the guideways.

12. In combination, a digester having a recessed charging nozzle, a screen seated within the recess and cooperating with the walls thereof to form a relief fluid chamber, a relief line extend-. ing through the side of the nozzle and communicating with the chamber, a rotatable chip distributor adapted to be, temporarily seated and operated within the nozzle, a distributor support extending across the opening, aligned guideways formed by parts on the nozzle and the screen for guiding the ends of the spider into operative position, and stops formed in the frame at the lower ends of the guideways.

13. In a digester, an exterior metal casing formed'with a charging opening at the top, a nozzle defining the opening, a flanged sleeve construction extending through the frame and the opening to a position within the casing with the flange of the sleeve resting upon the top of the nozzle so that the sleeve is thereby supported in its operative position, a digester fluid relief line extending through the side of the nozzle and communicating with a recess formed in the upper 2 part of the sleeve, a digester lining closely fitting around the inner ends of the sleeve and secured to the casing, and an easily detachable strainer ring closing the recess and combining with-the walls thereof to form a relief fluid chamber communicating with the relief line.

14. In combination, a digester having a charging nozzle at the top thereof, a recessed metallic sleeve extending into the opening, and an annular strainer which is channel shaped in cross section so that it will cooperate with the sides of the recess walls to form a fluid chamber for the digester relief line.

WILLIAM H. SHIPMAN.