US1958855A - Continuous beater system - Google Patents

Description

-msPfrr/avox 2l sheets-Sheet 1 fAM PAPER Mll/Vis amm? mx- I P. B. LACY CONTINUOUS BEA'IER SYSTEM Filed June 28A, 1929 May 15, 1934.

. STRAG ATTORNEY May 15, 1934. P. B. LAY Y CONTINUOUS -BEATER SYSTEM 2 Smets-sheet` 2 Filed June 28, 1929 INVENTOR ATTORNEY Patented May 15, 1934 UNITED STATES PATENT OFFICE CONTINUOUS BEATER SYSTEM Application June 28, 1929, Serial No. 374,458

24 Claims.

This invention relates to paper manufacture and more particularly to an improvement in the process and apparatus for preparing the pulp fibres for the paper-making machines and for systematically mixing the various ingredients which may enter into the sheet of paper.

The practice in paper-making has been to pump the pulp stock intermittently from the storage chest into beaters, or Hollanders, where the ysizing and coloring materials are added, and continue the beating process until the batch of bre is reduced to the desired state of disintegration. In following this practice, the beating is accomplished by means of revolving rolls carrying bars or knives which coact With the bars or knives of a bed plate to break up the fibrous material passing therebetween. When each batch is completed the beaten material is dumped into the beater chest by gravity, from which it may be pumped to the paper-making or Fourdrinier machines, Where the water is separated from the bres. Repeated efforts have been made to provide for the continuous operation of such beaters, by using perforated back falls and other means for withdrawing the disintegrated material, but

these have not proven commercially successfu1.`

-It is an object of my invention to provide a continuous process and improved means for beating the pulp.- It is a further object to provide a method for accurately controlling the consistency of the pulp liquor entering the beaters and for utilizing the white or back water and reclaimed stock from the save-all. Another` object is to provide an improved method for incorporating clay, coloring material, sizing and alum into the stock, and an improvement in the control of these ingredients. A further object is to avoid the cutting action of the beaters ordinarily used. Other objects and advantages will become apparent.

In describing my invention, reference will be made to the drawings, in which:

Figure 1 is a. diagrammaticview indicating the several steps of my improved process.

Figure 2 is a front elevation of my improved beater.

Figure 3 is a sectional view, taken on line 3--3 of Figure 2,-and

Figure 4 is a sectional view, taken on line 4'-4 of Figure 3.

In the preferred application of my invention, pulp stock, which has been treated by the sulphite, soda, or some other suitable process, and

having a consistency of about 2 to 5% fibres, is'

5 5 pumped from the storage chest (1) to a consistency regulating box (2)' and from there into a thickener (3) of standard construction. The thickener is operated to remove suicient water to produce a stock of considerably higher concentration than that desired in the beaters, for 6o example, one having a concentration greater than 8% of bre and preferably from 8 to 30% bre. This thickened stock is then passed through a regulator (4) where white oi back water, and/or reclaimed stock, from the paper machines, and additional fresh water, if necessary, are added to dilute the stock to the consistency of about 3 to 5% bre. This consistency should be such -that when the clay, color, alum and sizing have been added the stock will still be more concentrated than the minimum concentration permissible in the material fed to the paper-making machines.

Suitable quantities of clay, coloring material and alum are added as the stock passes to the beater tub 5). If these ingredients are added as liquids they may be accurately measured through a microscopically adjusted V-notch Weir. If it is preferred to add the alum, or other ingredients, in a dry form, they may be supplied through suitable standard dry-feed apparatus. The proper amount of alum may be -determined from the pH.1value, which may be indicated by a continuously recording hydrogen-ion indicator.

The stock is then pumped into the beater tub (5) and after passing through the beater tub is pumped through the inspectionbox (6), where the stock is automatically and accurately diluted to the concentration desired at this stage of the paper-making process. 'I'he stock may then be 90 pumped to the beater chest ('7), from which it may be Withdrawn as needed.

The beater tubs are shown in detail in Figures 2 to 4. These figures show awooden container (5) divided into three sections by wooden parti- 95 tions (8) and 9). Within each of these sections a cylindrical beater drum (l0), (10a) or (10b) is xed to a shaft (11) which passes through stuifing boxes in the ends'of the wooden tub andis rotated by a suitable source of power (not shown), through a gear (12). Each of the drums (l0), (10a) and (10b) has a perforated cylindrical surface and is open at each end. The perforations in the drum (10) are preferably about two inches in diameter, while those in the other two drums should be about one and one-half inches in diameter. The drums are of sufficient length to nearly contact with the wooden ends of the tub, leaving spaces therebetween which should be suflciently `small to prevent the passage of a substantial quantity of the fibres. The bottom of each section is curved to follow the circumference of the drum supported therein and scraping plates (13), may be Xed to the outer surface of each of the drums at spaced points and parallel to the axis of the cylinder. If desired, the scraping plate may extend around the drum in the form of a spiral.

An inlet pipe (14) enters one side of the first section of the beater tub above the upper surface of the drum (10); An outlet pipe (15) is connected to an end of this section of the beater tub at a point opposite the lower portion of the inner surface of the drum (10). This outlet leads to a centrifugal pump (16), the outlet side of which is connected to a bifurcated pipe having a branch (17) entering the first section of the beater tub above 'the drum (l0) and a branch (18) entering the second section of the beater tub above the cylinder (10a) The flow of liquid in the branches of this outlet pipe may be controlled by the valves (19) and (20). Similar pipes (15a), (15b), (17a), (17D), (18a) and (18h) connect the second and third sections of the beater tub with centrifugal pumps (16a) and (16h) The control of liquid from the last-mentioned centrifugal pumps may be regulated by valves (19a) and (19h), (20a) and (20h) The branch (18h) of the outlet pipe from the centrifugal pump (1Gb) is connected to the automatic consistency regulator (6) having an outlet (21) by which the beaten stock maybe conveyed to the beater chest (7).

In operating the beaters, the perforated drums (10), (10a) and (10b) are rotated at a speed ofabout ten revolutions per minute and the stock from the regulator (4) is conveyed continuously into the rst section of the beater tub by the pipe (14). This stock will splash upon the exposed perforated cylindrical surface of the rotating drum (1(1)) and the fibres will be drawn. with the liquid, through the perforations in the drum (l0) and through the outlet pipe (l5), by the centrifugal pump (16).

From the pump 16) the stock is forced through the branch (18) of the outlet pipe. to be splashed upon the exposed surface of the rotating perforated drum 10a) having somewhat smaller perforations. From this section it is pumped by a similar pump (16a) and pipes (15a) and (18a) to be splashed upon the perforated surface of the rotatingfdrum (10b) in the third section.

By-means of the valves (19), (19a) and (19h), in the branches (17), (17a) and (l'lb) of the outlet pipes from the centrifugal pumps, a portion, or all, of the stock may be bypassed to be recirculated and splashed upon the rotating drum in the section from which it has been withdrawn.

The level of the liquid in each section of the beater tub is maintained at a height of about twothirds the diameter of the cylindrical drum, by regulating the inlet and outlet supply. The fibres will be disintegrated and opened up by the splashing action upon the perforated drum surface, by being drawn through the perforations in the cylindrical surface, and by the beating action of the varies of the centrifugal pump.

By the time the stock containing the clay, coloring material and alum have reached the second section of the beater tub, the agitation will have completely distributed these materials through the remainder of the stock. At this point a measured quantity of sizing material, such as rosin soap, may be added by means of a spray pipe connected to a microscopically adjusted V-notched Weir.

Since the pH. value throughout the solution will have been made constant by the agitation, the

spraying of the rosin soap into the second beater will result in the uniform deposition upon the libres, of the rosin liberated by the reaction between the aluminum sulphate and rosin soap. A further advantage gained by following this procedure results from the complete distribution of the color and clay beforethe sizing is deposited, thereby permitting a uniform distribution of color' and filler throughout the fibres before they become coated with sizing. l

The recirculation of the pulp stock in each section of the beater tub may be regulated, by controlling the amount of stock being bypassed, to obtain the desired degree of agitation and disintegration.. When this is accomplished, the disintegrated stock from the last section of the beater tub may be conveyed through the branch pipe (18h) to the automatic consistency regulator (6) Where sufficient Water is added to bring the dilution up to'that required at this stage of the paper-making process, preferably to a concentration of 3 to 4% consistency. l

It is not new to thicken stock to slightly above the concentration required in pulp beaters and add a small quantity of water in the regulator. My process, however, includes the step of thickening to substantially above the concentration required in the pulp beater whereby all of the white or back water may be added at this point.

By the term back-water, as used in the description andclaims, I mean the water which separat-es from the paper-making material when the paper-making material is depositedton the Fourdrinier wire.- In other words, the water, passing through the wire, which water contains filler, short bres, coloring material, alum, sizing etc. f

By my procedure I provide for the addition of this white or back water at a point where the coloring material, alum, clay and sizing contained therein may be thoroughly agitated with the stock in the beaters and thereby used to the best advantage. By using this high degree of concentration in my process, all of the White or back water can be added without any separation thereby avoiding the loss occasioned by discarding this material or by separating it for use with stock of lower concentration.

Since the standard consistency regulators will only act to dilute the stock, it is important that the consistency of the stock, after it leaves the thickeners, be maintained at all times,v upto the time for diluting the stock in the consistency regulators, at a concentration higher than the minimum concentration permissible in the paper-making machines. By my process of thickening to substantially above the optimum concentration in the beaters, I provide not only for the economical utilization of valuable waste products, but also for the accurate control of the ingredients added to the stock, to produce a uniformly high quality of paper.

In my preferred operation, the process is continuous and one of its advantages lies in its avoidance of the delays attendant upon an intermittent or batch process.

I amalso aware that rotating cylinders have been used for filtering and separating solid materials and paper stock. My process is not one of separation, however, but rather one of disintegration. The splashing action of the pulp upon the rotating perforated surfaces, andthe contact with the metal While being drawn through the perforations, disintegrate and open up the fibre so that it may be suitable for use on the I paper-making machines. The scrapers (13) attached to the rotating drum serve to agitate the stock and prevent settling of the bres to the bottom of the tubs, and the blades of the centrifugal pumps cause further agitation of the pulp, and further disintegration andopening of the bres.

The construction of the 'beater tubs and drums may be altered and other means for splashing the pulp upon or 'drawing it through the perforated surfaces may be used. It is also apparent that many modifications in the means for scraping and for agitation or circulation of the stock may be used.

By using my method and apparatus for disintegrating and opening the fibres, I avoid the cutting of the fibres-which occurs between the bars and bed plate of the beaters or Hollanders in common use. My process has the further advantage of cleanliness, for the apparatus is entirely enclosed during the beating operation and there is no opportunity for dirt to be mixed with the stock during this operation.

In describing my invention, I have included references to a preferred procedure and have made specific references to certain details, such as the rate of rotation of the perforated drum and the size of the perforations in the drum, and certain ingredients to be added. These terms have been used for the purpose of illustrating the operation and are not intended to be interpreted as limiting it. It is apparent, for example, that other and more or less ingredients imay be mixed with the paper pulp, depending upon the particular type of paper being produced. It is also apparent that many other modifications and applications of my invention may be made and it is not intended to hereby linut its scope tothe particular embodiments described.

What I claim is:

1. A method for disintegrating paper pulp comprising splashing the pulp stock upon an exposed surface of a perforated drum while rotating the latter, and drawing the excess stock through perforations in the rotating drum.

2. A method for disintegrating paper pulp comprising splashing the pulp stock upon an exposed surface of a perforated drum while rotating the latter, drawing the excess stock through perforations in the drum and bypassing a portion of the stock for recirculation in the same manner.

3. A continuous method for disintegrating paper pulp comprising splashing pulp stock upon an exposed surface of one of a plurality of perforated drums while rotating the latter and impelling the stock to draw it successively through perforations in each of the said drums and to splash it successively upon the exposed perforated surfaces of each of the remaining drums. I

4. A method for disintegrating paper pulp comprising splashing pulp stock upon an exposed surface of one of a plurality of perforated drums while rotating the latter, impelling the stock to draw it successively through the perforations in each of the saiddrums and to splash it successively upon the exposed surfaces of each of the remaining drums, and bypassing a portion of saidstock to recirculate it through one or more of said rotating perforated drums.

5. In the preparation of paper pulp for the paper-making machines, the steps comprising thickening all of the pulp stock to a concentration of fibre of greater than 8 percent, adding substantially all the white or back-water lto dilute it to a concentration slightly above that desired in the paper-making machines, beating the diluted stock to disintegrate the bre and diluting it to the concentration desired in the paper-making machines.

6. In the preparation of paper pulp for thei i-t to a concentration slightly above that desired in the paper-making machines, splashing the diluted stock upon an exposed surface of a perforated drum while rotating the latter, drawing the stock through perforations in the drum, bypassing a portion of said stock to recirculate it through the perforated drum, and further diluting the stock from the beater to the concentration desired in the beater chest.

7. In the preparation of paper pulp for the paper-making machines, the steps comprising thickening the pulp stock to a concentration considerably greater than that desired in the beating operation, adding white or back-water to dilute it to a concentration slightly above -that desired in the paper-making machines, splashing .the

' diluted stock upon an exposed surface of one of a series of perforated drums while rotating the latter, impelling the stock to draw it successively through perforations in each of the said drums and to splash it successively upon the exposed perforated surfaces of each of the remaining drums.

8. In the preparation of paper pulp for the paper-making machines, the steps comprising thickening the pulp stock to a concentration considerably greater than that desired in the beating operation, adding white or back water to dilute it to a concentration Aslightly above that desired in the paper-making machines, splashing the diluted stock upon an exposed surface of one of a series of perforated drums while lrotating the latter, impelling the stock to draw it successively through the perforations in each 0f said drums and to splash it successively upon the exposed surface of -each of the remaining drums, bypassing a portion of said stock to recirculate it through one or more of said rotating perforated drums,

. and diluting the stock to the concentration desired in the stock entering the beater chest.

9. An apparatus for beating paper pulp comprising a tank, a rotatable perforated drum in said tank, means for splashing pulp stock upon an exposed surface of said perforated drum, and means for withdrawing pulp and liquid from the inner surface of said drum.

10. An apparatus for beating paper pulp comprising-a plurality of tanks, a rotatable perforated drum in each tank, means for splashing pulp stock upon an exposed surface of the flrst drum, means for withdrawing said stock from the inner side of each drum and for splashing it upon the surface of the next drum, and means for withdrawing the stock from'the inner surface of the last drum.

11. An apparatus for beating paper pulp comprising a plurality of tanks, a rotatable perforated drum in each tank, means for splashing pulp stock upon an exposed surface of the first drum, means for withdrawing said stock from the inner side of each drum to splash it upon the surface of the next drum, means for recirculating a portion of said stock through each drum, and means for withdrawing the stock from the inner surface of the last drum.

12. An apparatus for preparing paper pulp,

comprising a. thickener for increasing the concentration of the fibre in the pulp stock, means for diluting the thickened pulp stock with waste water from the paper machines as the pulp stock passes to a tank containing a perforated rotating drum positioned so that the pulp will splash upon an exposed surface of the drum, and means for withdrawing the pulp and liquid from the interior of the rotating drum.

13. An apparatus for beating paper pulp, comprising a plurality of perforated drums rotating in separate compartments, means for spraying the pulp upon an exposed surface of the first drum, means for withdrawing the pulp and liquid from the interior of the rst drum and spraying it upon the exposed surface of a succeeding drum, means for adding alum to the pulp stock beaten in the first compartment, means for adding sizing to the pulp stock beaten in a subsequent compartment, and means for withdrawing the beaten pulp stock from the interior of the perforated drum in the last compartment.

14. A method, for disintegrating paper pulp comprising splashing pulp stock upon an exposed surface of a rotating foraminous cylindrical plate, drawing the excess pulp stock through perforations in the plate and thereafter passing the pulp stock through a foraminous plate having perforations of smaller diameter.

15. A method for disintegrating paper pulp, comprising passing the pulp stock through a foraminous plate moving in the pulp stock and thereafter passing it through a second moving foraminous plate containing perforations of smaller diameter.

16. In the preparation of paper pulp for the paper making machines, the steps comprising thickening the pulp stock to such concentration that all of the white water or back water may be added to it without diluting it to a concentration below that desired in the paper making machines, adding white or back water to dilute the thickened pulp stock to a concentration slightly above that desired in the paper making machines, and beating the diluted stock to disintegrate the fibres.

17. In the preparation of paper pulp for paper making machines, the steps comprising thickening the pulp stock to such a concentration that all of the white or back water may be added to it without diluting it to a concentration below .that desired in the paper making machines, adding white or back water to dilute the thickened pulp stock to a'concentration slightly above that desired in the paper making machines, continuously passing the diluted stock through a perforated cylinder while rotating the latter and further diluting the stock to the desired concentration.

18. In the preparation of paper pulp for paper making machines, the steps comprising thickening the pulp stock to such a concentration that all of the white or back water may be added to it without diluting it to a concentration below that desired in the paper making machines, adding white or back water to dilute it to a oncentration slightly above that desired in the paper making machines, adding measured quantities of clay, color and sizing while continuously passing the diluted stock through a perforated cylinder in rotation, and further diluting the stock to the concentration desired in the paper making machine.

19. An apparatus for beating paper pulp, comprising a tank, a perforated plate positioned within said tank and having a portion beneath the liquid level therein, and means for repeatedly drawing pulp and liquid through the perforations in said plate positioned beneath the liquid level.

20. An apparatus for beating paper pulp, comprising a tank, a plurality of perforated plates each having a portion positioned beneath the liquid level in said tank and means for drawing pulp stock successively through submerged perforations in each of such plates.

21. An apparatus for beating paper pulp, comprising a plurality of tanks, a movable perforated plate in each such tank having a portion posi-A tioned below the liquid level therein, means for drawing pulp and liquid through submerged perforations in each such plate and conveying it to the succeeding tank.

22. An apparatus for beating paper pulp, comprising a tank, a foraminous plate in said tank partially submerged beneath the liquid level therein, a second partially submerged foraminous plate having perforations of smaller diameter, and means for passing pulp stock through the first foraminous plate and thereafter passing it through the second foraminous plate.

23. An apparatus for disintegrating paper pulp, comprising a plurality of movable foraminous plates partially submerged beneath the pulp stock, and means for drawing the pulp stock through .said foraminous plates in succession.

24. An apparatus for disintegrating paper pulp, comprising a tank, a cylindrical perforated plate rotatably mounted in said tank and having an open end inside of and adjacent a wall of said tank, means for supplying paper pulp to said tank, and a liquid outlet projecting through the wall of said tank at a point opposite the open end of said cylinder.

PAUL B. LACY.

Images