US1923888A - Method of producing emulsions - Google Patents

Description

Aug. 22, 1933 T. ROBINSON METHOD OF PRODUCING EMULSIONS Filed QOt. 30, 1931 ATTORNEYS PateatedAu 22, 1933 UNITED STATES METHOD OF PRODUCING-EMULSIONS Thomas Robinson, New York, N. Y., assignor to Lancaster Processes, Inc., New York, N. Y., a Corporation of New York Application October so, 1931. Serial No. 572,132

18 Claims.

This invention relates to a method of producing emulsions from materials, for example, of abituminous or 'pitchy character and also to a method of producing pulp by reduction of fibrous 5 substances, making an emulsion co-incidentally with .the preparation of the pulp, and dispersing the emulsion through the pulp to produce a mixture adapted for the production of boards, roofing materials, and various products of that character. The method of my invention is not restricted in utility to the emulsification of any particular product but for purposes of illustration, I shall describe the emulsification of asphalt with the understanding that this material is merely an example of many others which may be converted into an emulsion by my new method.

It is well known that asphalt and similar substances may be converted into an emulsion by introducing the substance in fluent form into a body of water containing an emulsifying material such as soap-or clay in suspension, and effecting thorough dispersion of the asphalt by agitation. When the material to be emulsified in such processes is not fluent at ordinary temperatures, it is usual to heat it to give it the desired fluidity and the water containing the emulsifying agent is also raised to a suitable temperature so that the introduction of the asphalt will not result in immediate coalescence thereof before emulsification can be accomplished.

It has also been proposed to produce a pulp by disintegration and comminution of fibrous and woody substances and to disperse an emulsion through the pulp. so that the pulp maybe sheeted out and then dried with the asphalt acting as a binder for the fibrous materials. So far 1 as I am aware, the production of such a pulpemulsion mixture has heretofore commonly involved emulsification and pulping as separate operations, after which the emulsion and pulp are combined and the emulsion dispersed through'the pulp.

As a result ofexperiments in this field; I have ascertained that when paper stock is reduced to pulp, for example, in the apparatus illustrated and described in my co-pending'application Serial No 5721130, filed October 30. 1931 the pulp- 'ing operation releases from the paper a substantial quantity of colloidal substances used for loading and finishing the-paper, and also present in the ink on' printed stock. These substances include clay, casein, coloring matter, linseed oil from the ink, etc., and may amount to from 5% to 20% of the dry weight of the paper, depending upon its character. These colloidal substances are capable of use when suspended in water as an emulsifying agent for asphalt and the like and, in one embodiment of my method, I take advantage of this fact to produce anemulsion rapidly and at low cost.

Broadly stated, my invention involves creating a circulating stream of water, emulsifying material, and material previously emulsified, introducing into this stream in fluid condition the material to be emulsified, agitating the mixture, and continuously withdrawing aportion of the stream from circulation, whilesupplying water and the emulsifying material to make up for that withdrawn.

In order to effect rapid emulsification of'the asphalt and to avoid substantial coalescence thereof, I confine the circulating fluid just beyond the point of introduction of the material to be emulsified to produce a thin annular stream, and

I agitate this stream preferablyby means of blades rotating at a high velocity and serving also to impel the-stream onward at high speed. The stream flows past these blades in such fashion that only the ends of the blades enter the stream, thus producing a rapid dispersion of the asphalt and emulsifying it before any considerable coalescence can take place. Preferably the agitation and propulsion of the fluid is carried on. by a number of sets of blades and the effectiveness of the later blades in the series is maintained by converting the rotational or whirling movement of the'stream resulting from the action of the blades into rectilinear movement, so that the stream enters each set of blades along a path substantially parallel to the axis of rotation thereof.

The circulating stream at one point in its travel enters a vortex chamber from which a portion of the material is diverted, while the remainder passes again along the path in which agitation occurs. The. material to'be emulsified enters the stream'just in front of the agitating devices in fluent condition and the temperature of the stream is not substantially less than the melting point of the material to be emulsified so that coalescence due to chilling cannot occur in substantial amounts.

In producing an emulsion-pulp mixture by my methodgI disintegratepaper stock while suspended in water, this disintegration freeing from the paper colloidal substances. I then separate the major portion of the pulp from the fluid conno emulsifying medium. After introduction of the material to be emulsified in the fluid and production of the emulsion by agitation, I introduce the emulsion into the major body of pulp and then subject this mixture to a further defibring action which effects dispersion of the emulsion.

through the pulp.

For a better understanding of the principles of my invention, reference may be made to the accompanying drawing, in which Fig. 1 illustrates in vertical section a machine which may be used for producing an emulsion according to my method, and

. bottom is a partition 14 of generally conical shape having an'open top. The space between the partition and the side wall serves as, a discharge chamber 15 from which leads a discharge outlet 16. The collecting chamber is provided with an exit defined by a tubular partition 1'7 projecting upwardly-above the bottom and this partition leads to a hopper 18 terminating in its lower end in a chamber 19. Extending radially from the chamber 19 and in communication therewith are disintegrating chambers or tubes 20. In the machine illustrated there are four such tubes arranged .in upper and lower levels with aligned tubes in the same level.

Mounted in aligned tubes is a shaft 21 extending out through the ends of the tubes, the tube ends being closed by gland devices generally designated 22. The shaft is supported in bearings .23 on standards 24 and is provided with a conplingdevice 25 sothat it-may be driven from anysuitable source of power. In the operation of the machine, the shaft is operated at a high speed, such as 3600 R. P. M.

Mounted on each shaft are sets of agitating and propelling blades 26, the sets of blades'being spaced apart along the shaft and the shaft carrying cylindrical collars 27 between sets of blades, and conical collars 28 at the ends of the sets of blades. Between the blades are disposed statorvanes-29 mounted in the tube wall and extending radially into the tube. The vanes terminate close to the surface of the collars 27 and with the collars define straight passages extending axially'of the tube. The collars reduce the worklug space in the tube to an extent such that fluid through the tube. assumes the form of a thin annular stream, into which the ends of the blades project. At the outer endof each tube is an offset discharge elbow 31 connected by an elbow 30 to; anozzle, 31 discharging tangentially ,into the. collecting chamber just above its bottom. A feed pipe 32 enters the collecting chamher from above and supplies fresh emulsifying material, or fresh paper stock to be pulped, the pipe 32 lying in alignment with the partition 17 and terminating a short distance above the top of .the partition.

Each tube 20 has an-opening formed inthe wall thereof at a point close to the connection .of the tube with the chamber Hand a pipe 33 for the introduction of material to be emulsified leads-to this opening. In the production of an emulsion in this mataining such substances and use that fluid as the chine in accordance with my method, water and an emulsifying material, such as soap, clay, etc.,

'is introduced through the feed pipe 32, the material entering the hopper 18 and chamber 19 whence the material is forced out through the tubes by the impeller blades. The water and emulsifying material are introduced into the machine at a relatively high temperature not substantiaHy less than the temperature at which the, material emulsified melts, although where the material to be emulsified is fluent at room ing motion but as the flow enters the spaces between the stator vanes, its whirling movement is converted in the rectilinear movement, creating turbulence and further dispersing the material to be emulsified through the stream. These operations continue until the stream leaves the last set of blades and is discharged through the connections into the bottom of the collecting chamber.

The material flows around that chamber in contact with the walls and, as more material is added to the stream, the level of the liquid in the chamber rises and it flows upward with a 1 whirling -motion along the under surface of the inclined partition until eventually overflow occurs, the discharged material passing out through the outlet 16. The material not discharged passes down through the center of the collecting cham- 1 her with a vortical flow and is'combined with fresh water and emulsifying material entering through the feed pipe. This mixture then enters the tubes and further material to be emulsified is added to it. 1

It will be evident that after the first circuit of the material through the machine, the material to be. emulsified enters a stream made up of water, emulsifying the material and material previously emulsified, and the asphalt or other substance tdbe emulsified is likely to pass through the agitating chamber a great many times before it is ultimately discharged. This produces a thorough dispersion of the asphalt through the stream and results in the production of an emulsion of uniform characteristics.

In the production of a pulp-emulsion mixture, the material supplied to the machine through the feed pipe may consistof water containing a mild detergent and paper in suspension therein. Preferably, a part of the'agitating devices are used merely for.pulping purposes and the remainder for the production of an emulsion. For

example, one tube may be used for emulsifying and the others for pulping, in which event the entrance to theemulsifying tube from the chamber 19 will be provided with a screen which will prevent entrance into that tube of the major portion-of the pulp and permit onlywater and 14 the colloidal substances released from the paper to pass although some fine fibres may also enter. .Thepaper suspended in water entering the retubes is disintegrated and defibred by the action of the blades and vanes and the pulp 14 produced is discharged into the collecting chamber where it is combined with the emulsion leaving the emulsifying tube. A part of they pulp and emulsion may then pass out over the top of the partition 14 while the remainder returns to be employed in one plant, some of the machines being used for the production of pulp and the others for the production of an emulsion. The liquid expressed from the finished pulp may then be used for emulsifying the asphalt in the machine devoted to that purpose. Where the machine is used for the purpose of producing a pulpemulsion mixture, the fluid and colloidal substances released from the paper may be withdrawn from the pulping operation and used for emulsifying purposes in the manner above described.

The collecting or vortex chamber constructed in the manner above described is particularly useful in the production of a pulp-emulsion mix-- ture. When pulp suspended in water is-introduced into the chamber through the tangential nozzles in the bottom, the stream flows upwardly with a whirling motion along the vertical sides of the chamber and then along the under side of the partition. As more fluid enters the cham-' her, the level of the body of fluid rises and fluid leaves the chamber through the central exit opening with a vortical flow. The larger, bulky particles of pulp remain in the main stream due to their inertia and thus pass again to the defibring tubes where further disintegration takes place, while the smaller, more completely disintegrated particles are thrown out of the main stream by centrifugal action. The consequence is that the material discharged contains finely divided pulp of substantially uniform characteristics. The rate at which pulp is discharged depends on the rate of feed and these factors, together with the speed of movement of the stream through the tubes, determines the number of times that the material will be acted on before being discharged from the stream and, therefore;

the character of the pulp. Since the emulsion enters the main body of pulp in the chamber and passes through the pulping tubes with the pulp, the emulsion is thoroughly distributed through it before discharge of the pulp takes place.

The apparatus disclosed in this applicationis similarto that illustrated in my co-pending application,'Serial No. 572,130, filed October 30, 1931, and the method of disintegrating paper to produce pulp as disclosed in this application is similar to that disclosed in my co-pending application. Serial No. 572,131, filed October 30, 1931.

What I claim:

l. A method of making emulsions which comprises creating'a circulating stream of water, emulsifying material and material previously emulsified, continuously introducing material to be emulsified into said stream-in fluid condition, agitating the mixture, and continuously withdrawing va portion of said stream from circulation.

2. A method of making emulsions which comprises creating a circulating stream of water,

emulsifying material and material previously emulsified, continuously introducing material tobe emulsified into said stream in fluid condition, continuously introducing water containing emulsifying material into said stream, agitating the mixture, and continuously withdrawing a portion of said stream from circulation.

' 3. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and material previously emulsified, continuously introducing material to be emulsified into said stream in fluid condition, continuously withdrawing a portion of said stream from circulation, continuously replenishing the water and emulsifying material withdrawn from said stream, and subjecting the circulating stream to agitation at a point just beyond the point of introduction of the material to be emulsified.

4. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and previously emulsified material, said stream being at an elevated temperature not substantially below the melting point of the material to be emulsified, continuously introducing material to be emulsified into said stream in fluid condition, subjecting the circulating stream to agitation'at a point just beyond the point of introduction of the material to be emulsified, and continuously withdrawing a portion of the stream from circulation.

5. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, subjecting the stream at a point beyond the point of introduction of the material to be emulsified to the action of rotary blades effecting agitation of the stream and impelling it onward, and

continuously withdrawing a portion of the stream from circulation.

6. A method of making emulsions which comprices creating a circulating stream of water,

emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, subjecting the stream at a point beyond the point of-introduction of the material to be emulsified to the action of rotary blades effecting agitation of the stream and impelling it onward with substantial rotational velocity, converting the whirling movement of the stream produced by the blades into rectilinear movement, and continuously withdrawing a portion of the stream from circulation.

7. A method of making emulsions which comprises creating a circulating stream of water,

emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, subjecting the stream at a point beyond the point of introduction of the material to be emulsified to agitation effected by spaced sets of blades,

said blades also impelllng the stream onward 'with a whirling motion, converting said, whirling movement to rectilinear movement between the sets of blades, and continuously withdrawing a portion of the stream from circulation.

8. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, confining the stream through a portion of its length just beyond the point of introduction of the material to beemulsifiedto produce a mm annular flow, subjecting the annular portion of the stream to agitation, and continuously divert ing a portion of the main stream. 9. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, confining the streamthrough a portion of its length just beyond the point of introduction of the material to be emulsified to produce a thin annular flow, subjecting the annular portion of the stream to agitation by means of rotary blades projecting into the stream andserving to impel it forward, continuously diverting a portion of the main stream, and continuously adding water and emulsifying material to the main stream.

10. A method of making emulsions which comprises creating a circulating stream of water, emulsifying material and previously emulsified material, continuously introducing material to be emulsified into said stream in fluid condition, confining the stream through a portion of its length just beyond the point of introduction of the material to be emulsified to produce a thin annular flow, subjecting the annular portion of the stream to agitation by means at blades entering the stream and impelling it onward with a whirling motion, converting the whirling motion of the stream to rectilinear flow and repeating the agitation and impulsion', continuously di-'- verting a portion of the main stream, and con tinuously adding water and emulsifying material to the main stream.

11. A method of making emulsions which comprises pulping paper by suspending the paper in water and disintegrating it, and employing the water and non-fibrous materials resulting from the pulping operation as an emulsifying agent.

12. A method of making emulsions which comprises pulping paper by suspending the paper in water and disintegrating it, separating the water and the colloidal materials contained in the paper from the fibrous material resulting from the pulping operation, introducing material to be emul sified into the separated fluid, and agitating the fluid thereafter.

13. A method oi making emulsions which com-" prises pulping paper by suspending the paper in water and disintegrating it, separating the major portion of the pulp from the water, and utilizing the water together with non-fibrous materi-.

als therein from the pulping operation as an prises pulping paper by suspending the paper in water and disintegrating it, separating the major .portion of the pulp from the water, introducing emulsified in fluid condition into the fluid remaining after said separation, and agitating said fluid.

16. A method of producing a pulp-emulsion mixture which comprises suspending paper in water, pulping the paper by disintegration and separation of the fibres thereof, separating the major portion of the pulp from the fluid, introducing the material to be emulsified in fluid conditon into the fluid remaining after said separation, agitating the fluid to eifect emulsification of said material, combining the emulsion and the pulp, and dispersing the emulsion through the pulp.

mixture which comprises suspending paper in waterat a temperature not substantially lower than the melting point of the material to be emulsified, pulping the paper to separate the fibres and release the loading" materials therefrom, separating the major portion of the fibrous pulp from the fluid, introducing the material to be emulsified in fluid condition into the fluid remaining after said separation, rapidly agitating the fluid to efiect emulsification of said material before substantial coalescence occurs, and dispersing the emulsion through the pulp.

18. A method of producing a pulp-emulsion mixture which comprises suspending paper in water, circulating the water and paper and, at one point in its flow, disintegrating the paper to produce pulp, withdrawing fluid and non-fibrous materials contained in the paper, introducing material to be emulsified into said fluid, and agitating the mixture to emulsify said material, combining the emulsion with the pulp and water mixture resulting from the disintegrating operation, subjecting said pulp-water-emulsion mixture to further disintegration effecting dispersion of the emulsion through the pulp, and withdrawing a portion of the water-pulp-emulsion mixture.

1 THOMAS ROBINSON.

17. A method of producing a pulp-emulsion

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