US1054926A - Evaporator. - Google Patents

Description

o. MANTIUS.

EVAPORATOR.

APPLICATION FILED MAR.13. 1908.

Patented Mar. 4, 1913.

2 SHEETS-SHE T'l.

VIII' 0. MANTI'US.

EvAPoRAToR. A APPLICATION VFILED MAR. 13 190B. 1,054,926, Patented Mar.4,1913.

u im! UNITED .sTATEs rATENT cEEIcE.

oTTo MANTIUS, or cnIcAeaILLINors,:AssIGNon-To zAaEisfnaA COMPANY, or CHICAGO, ILLINoIs,AcoE1 oEATIoN or MAINE.

Specification of Letters Patent.

PatentediMar.' 4, 1913.

` Animation mea march 13,1908. serial No. 420,814.

new and useful Improvements in Evaporators, of which the following is a tion.

This invention relates to evaporators and relatesl particularly to evaporators especially specificadesigned and adapted for the high concentration of solutions of caustic soda, caustic potash and other strong alkaline solutions.

As is well known, the high concentration of strongalkaline solutions can only be effected at high temperatures, say 230 degrees F., in a high vacuum, corresponding to a steam pressure in the evaporator of substantially 100 pounds. As is also well' known, strong alkaline solutions rapidly attack and corrode steel, wrought iron,-brass, &c., the corroding action thereof increasing with the temperature and the degree of con-I; however,

centration. Experience shows, that cast iron, having a continuous and very hard surface or scale is attacked ver little under conditions which would soonk estroy either steel, wrought iron or brass.`r

Among the objects of theinvention' are, therefore, to provide an evaporator the surfaces of which exposed to the action of the liquor being treated consist of cast iron having continuous hard surfaces orfscales; to eliminate to the greatest extent possible all joints in the parts of the eva orator exposed to the action of the material being treated, particularly-.at points below the liquor level; and to provide for usin heating tubes suil ciently strong to wit stand the high steam pressure to which they will be subjected in use'and supported in such manner that their connections to their supports will be unaffected by the pressure'to which they are subjected, and. so constructed that said joints may be readily tightened by means accessib le outside of the evaporator.

i A further object of the invention is to provide an evaporator adapted for the high concentration of alkaline solutions constructed and arranged to create a liquor cir culation in the evaporator, the circulation being of' hi h velocit-y. alongfthe heating surfaces of t e evaporator.

To eiect the foregoing,-.izabjectsa an evapo- .rator of my invention comprises the various features, combinations of features and details of construction hereinafter described and claimed. In the accompanying-drawings, in which my invention is fully illustrated-@Figure 1;

is a vertical central section of my improved evaporatorl taken' substantially on the line 1 1 of Fig. 3. Fig. 2 is an enlarged view, similar to Fig. 1, of the lower end of my improved evaporator. Figs. 3 and 4 are en larged plan sections taken substantially on the lines 3 3 and 4-4, respectively, of Fig. 1; and Fig. 5'is an enlarged view similar to Fig. 1, showing a modied form of my im, proved evaporator. r

Referring now tothe drawings, A designates, as a whole, the shell or casing of the evaporator, consisting, as'shown, of a.

vertically disposed cylinder the height of:

which is relatively much reater `than its diameter, desirablev dimensions in practice being,height from 12 to 16 feet, diameter `18 to 48 inches. vThe ends vof the shelll or casing A are closed by means of heads 1 and 2, preferably formed integral withthe side "Walls thereof, and to provide access to the interio 1` ofsaid shell or casing and for casting A the same, itis made in two separate sections connected together b a suitable transverse joint 3, the'relative lengths of the sections of said shell or casing being preferablyl such -that the joint 3 will be above the liquor level in said evaporator, indicated by the dotted line 4. i y

The heating tubes 5 extendlengthwise of the shell or casing A and are grouped at the center thereof so as to leave relatively wide s aces at the sides of said shell or casing. aid heating tubes are'supp'ortedin the following lmannv lFormed inv kthe lower head or end 1 of in proper position, to which are fitted 7 of the heating tubes the ends of said reduced end ortions 7 outside of the head or end L1 o said shell or casing, arejnuts 8. The joints between-the shoulders 9 on the heating tubes 5 and the head'or end 1 of the shell or casing, are packed by means ofsuitable gaskets 10 which mayl be made of anylflsuitable mateof the solution undergoing' treatment. In case o-f leakage in these-joints, they may be readily and conveniently rendered tight by merely setting up the nuts 8. The heating tubes 5 are open at their lower ends for reasons presently described. n i

To prevent lateralumovement of the upper ends of the beatings-tubes 5, which would soon cause the joints at the connections of said heating tubes to the lower head 1 of the evaporator casing A to open and leak, means are provided for securing or holding theupper ends of said tubes rigidly in position. As shown, said means consist of a spider, indicated as a whole by 11, comprising an outer ring 12, which tsyclosely into the interior of the evaporator casing A, and a plurality of centrally disposed thimbles 13 adapted to fit over projections 14 on the upper ends of the heating tubes 5, respectively, said outer ring 12 and thimbles'13 being connected into a rigid, unitary V- structure by arms 15 and 16. Said spider 11 rests loosely upon the projections 14 and is held in position, when the evaporator is assembled, by lugs 17 on the inner surface of the casing A.

lSupported within the casing A of the evaporator and surrounding the heating `tubes 5, is a baille 18 of such length and so positioned that it will extend from a point a short distance, say from nine inches to one foot, above the lower end of the evaporator casing upwardly to a point slightly above the liquor level 4. Said baille is smaller than the casing, thus leaving a space/19 between said bale and the sides of said casing which will be in open communication with the space 20 withinsaid baille adjacent to the lower end of the evaporator casing. The space 20 Within said A baiie 18 will thus form a passageway for the upward circulation of the liquor as it becomes heated by contact with the heating tubes 5 and the space 19 will form a downtake for-the downward circulation of the liquor .discharged from the upper end of the baille 18 in die operation of the evaporator.

' In cross section, the area of the passageway 20 will be much smaller than that of `the space 19, thus providing for a much higher liquor `velocity upwardly along the heating tubes than downwardly in the downtake 19, it being found in practice that much higher efficiency is attained with a high liquor velocity when in contact withthe heating surfaces and consequently much'greater economy in the oper-ation of the evaporator. The size of the baille 18 may be varied to provide any desired relation between the gassageways 19 and 20, to meet varying conitions and requirements or as opinions may differ as to the proper relation, the smaller.

the relative size of the passageway 20 the 'the projections 22.

higher the liquor velocity therein, and vice versa.

As shown, the battle is supported by arms or' projections 21 thereon, the ends of which rest in notched seats formed in projections 22 formed on the inner surface of the evaporator casing A. The position of the baille 18 within the casing A is defined by contact of the ends of the arms 21 with the side of theI casing A or with rigid portions of The casing A is provided in its upper end 2 with a vapor outlet 23 and to prevent entrainment of the liquor with the current of vapo-r passing out through the vapor outlet 23, a suitable baille is provided, consisting, as shown, of upper and lower plates 24 and 25, smaller in diameter than the interior of the casing A and an intermediate pla-te 26 of substantially the same size as the interior of the casing A and having a central opening 27, said plates being spaced apart and hung on rods 28 suspended from lugs 29 o-n the inner surface of the evaporator casing. The evaporator casing A is also provided with usual peep holes 30; a liquor inlet pipe 31 preferably directed downwardly in the liquor circulation downtake` or space 19; a liquor outlet 32, which preferably communicates with the interior of the casing at the extreme lower end thereof; a vacuum break 33; and av Vwater connection 34 to provide for washing out`the evaporator. All of the features last enumerated are old and well known in the art and may be of any desired or approved construction. As shown in Figs. l and 2 the'steam connections of my improved evaporator are as follows Secured to the lower head or end 1 of the evaporator casing is a drum 35, the lower end of which is closed preferably by a removable head 36 and the interior of which is divided by a transverse partition 37 into closed compartments 38 and 39. The lower compartment 38 forms the steam chest of the evaporator and communicating therewith is a pipe 40 adapted for connection with a suitable source of steam supply,` not shown. The upper compartment 39 of the drum 35 is in open communication with the interiors .of theV heating tubes 5 and `forms a settling chamber forfcondensed in open communication with the steam chest 38 and which extend upwardly within the heating tubes 5, preferably to within a short distance of their upper ends. The steam will thus enter the upper ends of said heating tubes and its course will be downwardly therein, gradually giving up its heat to thel liquor contained in the evaporator as it descends. The upper ends of' said heating tubes will thus be heated to the highest degree, the temperature thereof falling gradually toward their lower ends, a relation which will produce the best possible liquor circulation, as the liquor passing upward through the baille 18 will always be entering' what may be termed zones of higher temperature from which the radiation will be more rapid.A

VThe modified form of construction show-n in Fig. 5, which I will now describe, relates merely to a modified .form of steam connec-- openings of said connections 44, as nearly as practicable in axial alinement with the heating tubes 5, are the steam pipes 421. As shown said' steam pipes 421 are screw threadedinto said openings and project outside of the same to provide for making steam connections directly thereto.

With the construction 'shown in Fig. 5,

any leakage in the joints connecting the heating tubes 5 with the lower end or head of the evaporator casing A can be at once detected and said joints rendered tight by setting up the nuts 8, without disconnecting any part of the evaporator.

With theconstruction shown in Figs. l

and 2, leakage in the joints around the heat-- ing tubes could only be detected by the presence of alkali in the water discharged from the drain pipe 41 or by removing the drum 35 and making. an examination and, in either case, to ftighten said joints would involve detaching the drum in order to tighten the nuts 8.

With an'V evaporator constructed as described, it is obvious thatl all of the interior surfaces of the evaporator exposed to the action of the liquor being treated will be continuous and hard so as to resist to the utmost the'corroding action of the liquor ported in any desired manner. As shown it is indicated as mounted on trunnions 47 formed on a ring 48 clamped around the body of the" evaporator, the position of which is defined by lugs 49 on the evaporator casingA.' The trunnion bearings may be formed in any suitable fixed support indicated at 50. Trunnion bearings are primarily for convenience in removing and replacing theparts of the evaporator inclosed within the casing A, particularly the heat ing tubes 5 andthe baille 18. Where the space above and below the evaporator is suiiicient to permit the various parts to be removed and replaced vertically, the evaporator may be-mounted permanently in vertical position. When trunnion bea-rings are used, as indicated, means are provided 'for locking or securing the evaporator in vertical position. As said means are in no way related to the present invention, they are not shown.

l. An evaporator for eecting high concentration, comprising an upright shell or casing 12 feet long, as a minimum, and hav- -ing a diameter substantially equal to of its length, as a maximum, upright heating tubes mounted in the lower end of said shell or casing the length of which is substan- A t-ially equal to o i the length of said shell or casing, as a irinimum, and a baille supported within said shell or casing and which defines a passageway upwardly among said.

heating tubes on one side thereof, and. a down-t-ake .on the other side thereof, the lower end of said baliie terminating above the bottom of the shell or casing and its upper end terminating substantially on a level with v'the upper ends of said heating tubes, substantially as described.

2. An evaporator .for eHect-i'ng high concentration comprising an upright shell or casing 12 feet long, as a minimum, and having a diameter substantially equal to of its lengt-h, as a maximum, .upright heating tubes mounted in the lower end of said shell or casing the length of which is substantially equal to 92 o f the'length of said shell or casing, as a minimum, and a baiiie supported wit-hin the said shell or casing and which defines a passageway upwardly among said heating tubes on one side thereof, and a down-take on the other side thereof, the lower end 0f said battle terminating above the bottom of the shell or casing and its'upper end terminating substantially' on a flevel with the upper ends of said heating tubes, the area in cross section of the upward passageway defined by said baiiie being'substantially of the area in cross section of the shell or casing, as a maximum,

substantially as described.

3. An evaporator for effecting high concentration, comprising an upright shell or casing substantially fourteen feet long and 2g; feet in diameter, upright heating tubes mounted in the lower end of said shell br casing substantially 8 feet in length, and a baffle within said shell or casing and which defines a passageway upwardly among said heating tubes on one side thereof, and a down-take on the other side thereof, the lower end of said baflie terminating above the bottom of the shell or casing and its upper end terminating substantially on a level with the upper ends of said heating tubes, substantially as described.

4. An evaporator for eecting high concentration, comprising an upright shell or casing substantially l4rfeet long and 2% feet in diameter, a central group of upright heating tubes mounted in the lower end of said shell or casing, said heating tubes being substantially 8 feet long, and a baille substantially 1% feet in diameter supported within said shell or casing and which sur rounds said group of heating tubes, the lower end of said baffle terminating above the bottom of the said shell or casing and its upper end extending substantially level with the upper ends of said heating tubes, substantially as described.

5. An evaporator for effecting high concentration, comprising an upright cast iron shell or casing substantially 12 feet long, as a minimum, and having a diameter substantially equal to 9; of its length, as a maXi-.A

muu, upright cast iron heating tubes mount- .ed in the lower-end of said shell or casing the length of which is substantially equal t0 of the length of said shell or casing, as a minimum, and a cast iron baflle supported within said shell or casing and which delines a passageway upwardly among said heating tubes on one side thereof, and a down-take on the other side thereof, the lower end off-said baffle terminating above the bottom of the shell or casing and its vupper end terminating substant-ially on a [level with the upper ends of said heating tubes, the scale on the surfaces of said shell undergoing treatment being practically unbroken.

6. An evaporator comprising a shell or casing, heating tubes thereinl an end of each of which projects through and is rigidly secured in the lower end of said shell or casing, the ends of said .heating tubes which project outside of said shell or casing being open and their inner ends being closed, means for supporting the upper ends of said heating tubes against lateral movement, said means consisting of a spider comprising a ring litted to the interior of the shell or casing', thimbles and arms which connect said ring with said t-himbles, and projections on the upper ends of lsaid heating tubes which engage said thimbles.

i'. An evaporator comprising a shell or casing, heating tubes therein an end of each of which projects through and is rigidly secured inthe lower end of said shell or casing, the ends of said heating tubes which project outside of said shell or casing being open and their inner ends being closed, means for supporting the upper ends of said heating tubes against lateral movement, said means consisting of a spider comprising a ring littecl to the interior of the shell or casing, thimbles and arms which connect said ring with said thimbles, projections on the upper ends of said heating tubes which engage said thimbles and lugs on the inner surface of the shell or casing of the evaporator which hold said spider in engagement with said projections.

In testimony, that I claim the foregoing as my invention, I aix my signature in presence of two subscribing witnesses, this 4th day of March, A. D. 1908.

OTTO MANTIUS.

Witnesses:

K. A. COSTELLO, M. V. MCGRATH.

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