US369836A - blackman - Google Patents

Description

3 Sheets-Sheet 1.

H. BLAGKMAN.

DISINTEGRATING FIBERS AND MANUFACTURING PAPER PULP.

No. 369.836. Patented Sept. 13, 1887,

(No Model.) 3 Sheets-Sheet 2.

V H. BLAOKMAN. DISINTBGRATING FIBERS AND MANUFACTURING PAPER PULP.-

No. 369,836. Patented Sept. 13, 1887.

a A I umla7 (No Model.) 3 Sheets-Sheet 3. H. BLAOKMAN.

D'ISINTBGRATING FIBERS AND MANUFACTURING PAPER PULP. No. 369,836. Patented Sept. 13, 1887.

a iiaitiii Q INVENTOR d'Z mm flm/wmm. By his A/{or/zeys. cm rLW g WITNESSES 2 To all whom it may concern.-

.turing Paper-Pulp, of which the following is integrated by boiling them under pressure in ,tegration based upon the same principle, which stance to be reduced to pulp is placed in a UNITED STATES PATENT OFFICE.

- HENRY BLAGKMAN, OF NEW YORK, N. Y.

DISINTEGRATING FIBERS AND MANUFACTURING PAPER-PULP.

SPECIFICATION forming part of Letters Patent No. 369.836. dated September 13, 1887.

Application filed May 11, 1886. Renewed August 5, 1887. Serial No. 246,208. (No moat-1.)

Be it known that I, HENRY BLAcKMAma citizen of the United States, residing in the city, county, and State of New York, have invented certain new and useful Improvements in Disintegrating Fibers and Manufaca specification. I

My invention relates to the manufacture of paper-pulp from wood, straw, jute, or other fibrous substances.

Prior to my invention fibers have been disa closed vessel, usually with an alkali or other chemical, and when sufliciently softened by this treatment opening the outletof the vessel and discharging its contents suddenly into the atmosphere. Duringthis discharge the overheated liquid in the cells or interspaces between t-he fibers, being relieved of pressure, suddenly vaporizcs and expands, tearing the fibers asunder. This method of exploding the fibrous substances is objectionable in many respects, among others the scattering of the fibrous mattcr in all directions and the large space required.

My invention provides a method of disinis designed to overcome the difiiculties heretot'ore encountered.

My invention relates both to the method of treatment and to the apparatus for practicing that method.

According to my invention the fibrous subclosed digesting-vessel and exposedto the action of water, with or without other chemicals, and under more or less pressure, until the material is sufficiently dissolved or softened. This done, the'material, being at the time charged with fluidunder heavy pressure, is forced out from the digestcr through a con; tracted no'zzleorinlet-opening, which enters a vacuum-chamber, and thematerial as it esrnpted by the sudden expansion or explosion of the fluid (steam or superheated water) in the interstices of the'fihers. The explosive action is more efl'ective by occurring in a partial vacuum, and this vacuum ismaintained by the continuous action of an air-pump or other suitableexhausting device. The destruction of the vacuum by the expansion of the steam in the vacuum-chamber is prevented by the nozzle, which is so contracted that it retards the admission of fibrous material and liquid, admitting it in so reduced a stream that the steam therefrom is of no greater volume than the capacity of the pump will suffice to draw ofl'. To quickly reduce the volume of the steam after its expansion and assistin maintaining the vacuum, the chamber is continually cooled after the manner of a condenser,preferably by showering cold water into. it through jet-pipes. This water mingles with the disrupted fibrous material, and the whole is drawn off and subjected to further treatment.

In order to thoroughly separate the fibers and reduce the entire fibrous mass to a uniform condition, Ipump the same, with water, through a long tortuous passage as a coil of pipewherein obstructions are provided to agitate the fibers. When this action is completed, the dilutedfibrous matter or pulp is washed through ascries of traps or separators, by which the hard particles and grit are arrested. The pulp is then flowed over screens and sprinkled with jets of water to wash and screen out the coarser particles. v

The accompanying drawingsshow the apparatus constructed according to my invention and used for practicing my improved process.

Figure 1 is a vertical section of the digestcr and vacuum-chamber and an elevation of the coil and pump. Fig.2 is a vertical section, and Fig. 3 a cross-section, of a fragment of the coil on a larger scale; and Fig. 4 is avcrtical section showing a modification of portion of the apparatus. Fig, 5 is a vertical section showing a modification ofthe vacuum-chamber and exhauster. v

In Fig. l, A designates the dig-ester, which is a strong closed vessel capable of withstanding a considerable prcssureand of such material or lined with such; material as will resist the action of the chemicals used. A steampipe, B, enters it, preferably from the top,and

extends to or nearly to the bottom. There may also be another steam-pipe, B, entering the vessel and terminatingnear the middle thereof. A man-hole, O,is provided, preferably at the top, through which to introduce LOO ing properly comminuted, is introduced into the digester through the man-hole C, and the digester is closed. Vater is introduced either with the material or separately, and either with or without any suitable chemical agentssuch as alkali or snlphurous acid, or other substances, according to'the chemical process which is preferred. Steam is turned on and the mass is subjected to heat,with more or less pressure, (or, if preferred, without pressure, or even in v'acuo,) for a suflicient length of time and until the fibrous matter is properly dissolved or softened. When the mass is ready to be discharged,itis blown out through the pipe E into the vacuum-chamber F, where it is disrupted by the expansive action. The discharge is effected by opening the cock D, when the pressure of steam within the digester forces out the pulp and water. If there is not sufli eient pressure alreadyin the digester, steam is to be admitted through the pi pe'B'. ,It is preferable to drain 011 through the tap c any chemicals that have been used and reclaim them, introducing water in their place (if necessary) to dilute the semi-pulpy fibrous matter to the proper fluidity to enable it to flow properly; or the fibrous matter might be forced out by the steanrpressure without adding water. In such case it is only essential that the fibrous matter shall have been sufficiently softened to be capable of disruption, that the fluid-pressure shall have penetrated its interstices, and that there be sufiicient pressure both to disrupt the fibers after passing the nozzle and to force the fibrous matter through the nozzle.

The flow of the fibrous material and water.

through the pipe E is retarded by the nozzle 0, which holds back .the stream, as it were, and admits only a comparatively small jet into the vacuum-chamber F. As the fibrous matter passes the nozzle and emerges into the vacuum, it is suddenly relieved from pressure and the steam in the interstices of the fibers expands and tears them apart. This expansion is due, in a measure, to the vaporization of the water, which has been heated ahove the boiling-point but its ebullition suppressed by the superincumbent pressure until its 'discharge at the nozzle. Iprovide in the. pipe E a steam-jet pipe, d, adapted to discharge ajet of steam into the mass of fibrous material in order to increase its pressure by acting against it on the principle of the injector. The steam enters through a pipe, f, and is controlled by a valve, 9, the jet being regulated by ascrewpin or cone, h, as is usual in boiler-injectors. This injector is chiefly useful when the pressure in the digester is too low to cause a. sufficiently forcible disruptive action. It is also useful when there is any clogging in the pi pe E.

The vacuum-chamber F is of any convenient shape and of suitable size. It is preferably divided into two compartments by a partition, F, which serves as a shield or target to receive the impact of the fibrous matters projected from the nozzle. The harder particles-such as bits of knots-which are not blown apart .by the expansion of the steam, are aided in their disintegration by striking this target. The fibrous mass falls to the bottom of the chamber, whence it is washed under the partition and carried down the pipe F to the pump F. This pump is operated by asteamengine, G, or other source of power, and acts to draw the pulpy matter, water, and vapors from the chamber F, and to maintain a partial vacuum therein. Separate pumps may be used, if preferred, for the liquids and vapors; but one will serve for both.

The maintenance of the vacuum is materially facilitated by showering water into the chamber F, which acts to condense the steam therein. A perforated pipe, P P, enters the chamber and receives water under premnre, which it discharges into both compartments in jets. This water lningles with thepulp and further liquelies it. A surface condenser might be used in place of a jet-condenser, if desired; but I prefer the latter.

The capacity of the pump F must be such that with a given pressure upon the entering pulp and water and a given area of nozzle,and with a given condensation due to the showering of water, the suction of the pump will draw off the vapors from the vacuum-chamber faster than they enter it, in order to maintain a sufficient vacuum therein. I prefer a vacuum of about twenty-seven inches; but this may vary. Even a slight rarefaction, sutiicient to draw 0d the vapors as fast as they enter, so as to afford a free space to receive the entering pulp, water, and steam from the nozzle, is of great advantage, as otherwise a pressure would soon accumulate in the chamber F, (even if it were provided with escapeopenings for the steam,) which would materially reduce the effectiveness of the disruptive action in tearing apart the fibers.

In place of the pump F,any othersuitable device may be employed for exhaustingthe vapors from the chamber F-as an injector, for example, as will be presently described.

From the pump the pulp and water is forced through, an extended and preferably tortuous passage, in which are agitating obstructions. The coil R R of pipe affords the extended passage, in passing through which the pulp flows up and down, being agitated by the bubbling through it of the steam and gases, and by contact with suitable mechanical obstructions against which the liquid flows, thereby gently rubbing the fibers and promoting their separation. This method of agitating the pulp and separating the fibers I do not claim of itself in this application, but shall make it broadly the subject of another application for patent to be filed byme.

Figs. 2 and 3 show the obstructions in the coil R, consisting of wire helices N N, preferably three in number, arranged triangularly. The coil R terminates in the first of a series of precipitating vessels or troughs, SS S". Dipping into these vessels are partitions 3, 4. and 5, and between them'are dams 6, 7, and 8. The pulp andjwater entering the upper vessel flows down under the partition 3 and up over the dam 6 into the second vessel. There may be any number of vessels, and in each the liquid flows downward under apartition and then upward over a dam. As it flows downward, its heavier particles are directed toward the bottom, where they fall and lie undisturbed by the current above them. In this manner any particles of sand, grit, or other heavy foreign bodies are removed from the pulp. The pulp flows from thclower vessel onto an inclined screen, S, where it is sprinkled or showered with water from pipes I I. The pulp is thus washed through the meshes of the screen; but any coarse particles are arrested and retained on the screen. Beneath this screen is another screen, T, of finer mesh, on which the pulp is again rinsed or showered with water from pipes J J. The fine pulp passes through this screen and'falls on an inclined endless apron, Q, of muslin or other fine fabric, turning over rollers 25 26. The water flows through the fabric, leaving the fibrous matter on the apron, whence as the apron revolves it is delivered at the roller 26. A'sprinklcr, K, may be used to still further wash the pulp on the apron. Any other desired method of delivering the pulp or fibrous matter may be used instead of that here shown.

Fig. 4 shows a modified construction of screens for washing the pulp. From the vessel S the pulp tlows upon an endless screen, S, of wire-cloth, which is carried around rollers 13 13. An inclined plate, 23, receives the pulp as it is washed through the screen S, and carries it onto a second endless screen, '1, of wire-cloth of finer mesh. An inclined plate, 19, receives the pulp which passes through the screen T and directs it onto the apron Q, where the water is drained off and the pulp is delivered over the roller 26. The screensST are caused to revolve, and the coarse particles separated from the pulp are dropped off at their ends or are washed off fronnthe under sides.

In Fig. 5a modification of my apparatus is illustrated, wherein the suction-pump F is omitted and an injector substituted. The digester A, steam-pipes B B, valve D, steaminjectorfy hd, and outlet-pipe E are all of substantially the same construction already described. In place of the pump F for exhausting the vapors, there is a hydraulic injector or ejector, F, connected to the vacuumchamber. This ejector employs a column of water under pressure, which passes through a nozzle in such manner as to produce a powerful suction around the nozzle in a space or chamber which communicates with the vacu um-chamber. supplied through a pipe, 1', and enters the nozzle H, being controlled by a valve, j,which is adjustable vertically by a screw, 10, in order to close the nozzle H more or less. The column of water issuing rapidly from'the nozzle H passes downwardly into a flaring tube, m. A chamber, K, surrounds the nozzle, and is connected by a tube, 0, with'the vacuumchamber F, so that the suction produced by the water acts to exhaust the vapors from the chamber F and maintain the partial vacuum therein. The water flows off through the pipe L, carrying with it any fibers that may have been drawn off with the vapors, these fibers being recovered by means of a sieve. This ejector device for exhausting the vacuum- .chamber is not recommended as a substitute for the pump, but may be used to advantage in some situations where there is an abundance of water at an elevated head.

' In place of using alarge pipe, E, terminat ing in a contracted nozzle, the pipe may be made as small as the nozzle throughout its entire length. in which case the end of the pipe where it entered the chamber F would constitute in effect anozzle. By the term nozzle I mean the inlet to the vacuumchamber, and by contracted nozzle I mean such an inlet which is contracted relatively to the pressure, the rapidity of condensation, and the capacity of the pump, so that it admits the pulp and water no faster than thevacuum can be maintained. length, and the vacuum-chamber may be arranged at any desired height. I t preferred, the vacuum-chamber may be arranged low down and the pipe E be made very short.

I claim as my invention- 1. The improvement in the art. of disintegrating fibrous substances, which consists in charging them with fluid under pressure and at a high temperature and forcing them in a reduced stream into a partial vacuum, whereby the expansion of the fluid when liberated in the vacuum disrupts the fibers.

2. The im 'n'ovementin the art of disintegrating Iibrous substances, which consists in The pipe E may be of greater or lessv The water under pressure is softening the fibers by digesting them in a closed vessel, charging the softened fibers with fluid under pressure and at a high temperature, and forcing them through a contracted nozzle or inlet into a partial vacuum, whereby the expansion of the fluid when liberated in the vacuum disrupts the fibers.

3. The improvement in the art of disintegrating fibrous substances, which consists in softening the fibers by chemical treatment, charging the softened fibers with fluid under pressure and at a high temperature, and forcing them through a contracted nozzle or inlet into a partial vacuum.

4. The improvement in the art of disintegrating fibrous substances, which consists in softening the same by treatment with liquid ure therein.

6. The improvement in the art of disintegrating fibrous substances, which consists in forcing the same with liquid under heat and pressure through a contracted nozzle or inlet into a vacuum-chamber, condensing the steam therein, and drawing oil the contents of said chamber at a rate sufiicient to maintain a partial vacuum therein. e

7. The improvement in the mannfacturepf paper-pulp, which consists in first softening a fibrous substance by treatment with liquid, then disrupting the fibers by liberating them under heat and pressure in a closed chamber, and then forcing the fibers with water through an extended passage containing agitating 0bstructions, whereby the fibers are separated.

8. The improvement in the manufacture of paper-pulp, which consists in first softening a fibrous substance by treatment with liquid,

then disrupting the fibers by liberating them under heat and pressure in a closed chamber, and subsequent] y separating the heavier particles by precipitation from the fluid pulp.

9. The improvement in the manufacture of paper-pulp, which consists in first softening a t'i'ons; fourth, separating the heavier foreign fibrous substance by treatment with liquid, then disrupting the fibers by liberating them I under heat and pressure in a closed chamber, Y and finally washing the pulp through screens to remove the coarser particles.

10. The improvement in the manufacture of paper-pulp, which consists of the following succession of steps: first, softening the fibrous substance by treatment with liquid; second," disrnpting the fibers by'liberating them under heat and pressure in a closed chamber; third, forcing the fibers with water through an .extended passage containing agitating obstrucparticles by precipitation, and, fifth, separating the coarser particles by washing through screens.

11. An apparatus for disintegrating fibrous substances, consisting of the combination of a digester, avacuum-chamber, an out-Ietpassage from the digester to said chamber, and a valve in said passage, substantially as set forth.

12. The combination of a digester, a vacuum-chamber, an outlet-passage from the di: gcsiter to said'chamber, a valve in said passage, an said chamber and adapted to maintain avacuum therein, substantially as set forth.

13. Thecombination of a digester, a vacuum-cham'ber, an outlet-passage from the digestertosaid chamber. avalve in said passage,

and a condenser arranged and adapted to condense the steam in said chamber, substantially as set forth. I a

14. The combination of ,a dig'oster, a vacuum-chamber, an ontlet-valve to the digester, a discharge pipe or passage leading thence to said chamber, and a steam jet pipe or' injector in said passage, substantially as set forth.

15. The combination of a digester, a vacuum-chamber, an outlet passage from said digester to said chamber, a contracted nozzle combination with a pump to force thepulpthrough the coil and helices, substantially as set forth.

, 18.-ln a pulp-making apparatus, a separator for precipitating heavy particles, consisting of asuccession of vessels provided with alternate downwardly-projecting partitions under which the liquid must flow and dams over which it must flow, substantially as set forth.

v19. The combination of the pump, the agitating-coil, and the separator for precipitating the heavier particles, receiving the pulp as it leaves said coiL-substantiallyas set forth.

20. In a pulp-making apparatus, a screening device for separating coarse particles. consistingv of one or more fine screens over which the-pulp is flowed, with sprinklers arranged to shower water thereon, and an endless traveling apron receiving the pulp as it passes through said screen and adapted to drain it of water, substantially as set forth.

Signed by me this 11th day of May, A. D. 1886.

Gno. T. Piscxsav,

G- MO'ITQ an exhausting apparatus connected to er, substantially as setr to

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