US3647493A - Method and apparatus for continuously producing solutions and suspensions - Google Patents
Method and apparatus for continuously producing solutions and suspensions Download PDFInfo
- Publication number
- US3647493A US3647493A US875962A US3647493DA US3647493A US 3647493 A US3647493 A US 3647493A US 875962 A US875962 A US 875962A US 3647493D A US3647493D A US 3647493DA US 3647493 A US3647493 A US 3647493A
- Authority
- US
- United States
- Prior art keywords
- particles
- solvent
- suspensions
- whirling
- mass
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims abstract description 31
- 239000000725 suspension Substances 0.000 title abstract description 19
- 239000002904 solvent Substances 0.000 claims abstract description 21
- 239000002245 particle Substances 0.000 abstract description 22
- 239000000126 substance Substances 0.000 abstract description 9
- 230000015572 biosynthetic process Effects 0.000 abstract description 6
- 238000004898 kneading Methods 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 5
- 238000006243 chemical reaction Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 4
- 238000013019 agitation Methods 0.000 abstract description 3
- 239000007787 solid Substances 0.000 description 14
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 9
- 239000000047 product Substances 0.000 description 8
- 239000007788 liquid Substances 0.000 description 7
- 238000010420 art technique Methods 0.000 description 4
- 229920002239 polyacrylonitrile Polymers 0.000 description 4
- 230000035515 penetration Effects 0.000 description 3
- 238000009987 spinning Methods 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 2
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 235000015164 Iris germanica var. florentina Nutrition 0.000 description 1
- 235000015265 Iris pallida Nutrition 0.000 description 1
- 244000050403 Iris x germanica Species 0.000 description 1
- SMEGJBVQLJJKKX-HOTMZDKISA-N [(2R,3S,4S,5R,6R)-5-acetyloxy-3,4,6-trihydroxyoxan-2-yl]methyl acetate Chemical compound CC(=O)OC[C@@H]1[C@H]([C@@H]([C@H]([C@@H](O1)O)OC(=O)C)O)O SMEGJBVQLJJKKX-HOTMZDKISA-N 0.000 description 1
- 229940081735 acetylcellulose Drugs 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 230000002301 combined effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000007863 gel particle Substances 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004383 yellowing Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/717—Feed mechanisms characterised by the means for feeding the components to the mixer
- B01F35/71705—Feed mechanisms characterised by the means for feeding the components to the mixer using belts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B7/00—Mixing; Kneading
- B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
- B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
- B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
- B29B7/40—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft
- B29B7/42—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft with screw or helix
- B29B7/426—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft with screw or helix with consecutive casings or screws, e.g. for charging, discharging, mixing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
- B01F27/60—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a horizontal or inclined axis
- B01F27/72—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a horizontal or inclined axis with helices or sections of helices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F33/00—Other mixers; Mixing plants; Combinations of mixers
- B01F33/80—Mixing plants; Combinations of mixers
- B01F33/82—Combinations of dissimilar mixers
- B01F33/821—Combinations of dissimilar mixers with consecutive receptacles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F33/00—Other mixers; Mixing plants; Combinations of mixers
- B01F33/80—Mixing plants; Combinations of mixers
- B01F33/83—Mixing plants specially adapted for mixing in combination with disintegrating operations
- B01F33/831—Devices with consecutive working receptacles, e.g. with two intermeshing tools in one of the receptacles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/711—Feed mechanisms for feeding a mixture of components, i.e. solids in liquid, solids in a gas stream
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/712—Feed mechanisms for feeding fluids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/714—Feed mechanisms for feeding predetermined amounts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/717—Feed mechanisms characterised by the means for feeding the components to the mixer
- B01F35/7173—Feed mechanisms characterised by the means for feeding the components to the mixer using gravity, e.g. from a hopper
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/285—Feeding the extrusion material to the extruder
- B29C48/286—Raw material dosing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/285—Feeding the extrusion material to the extruder
- B29C48/29—Feeding the extrusion material to the extruder in liquid form
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/375—Plasticisers, homogenisers or feeders comprising two or more stages
- B29C48/38—Plasticisers, homogenisers or feeders comprising two or more stages using two or more serially arranged screws in the same barrel
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
- B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
- B01F35/71—Feed mechanisms
- B01F35/717—Feed mechanisms characterised by the means for feeding the components to the mixer
- B01F35/7176—Feed mechanisms characterised by the means for feeding the components to the mixer using pumps
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/0005—Condition, form or state of moulded material or of the material to be shaped containing compounding ingredients
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S516/00—Colloid systems and wetting agents; subcombinations thereof; processes of
- Y10S516/924—Significant dispersive or manipulative operation or step in making or stabilizing colloid system
- Y10S516/929—Specified combination of agitation steps, e.g. mixing to make subcombination composition followed by homogenization
- Y10S516/931—High shear followed by low shear
Definitions
- the novel in- Rehned s Appucafion Data vention serves to effect a continuous dissolving process of a chemical solute in a solvent and does so in a fashion which [63] commuatlonm'part of 5 prevents the formation of agglomerates and jellylike skin on 1966- the particles and serves to dissolve or suspend such materials without introducing high sheer force into the product.
- the novel invention contemplates to Dec. 20, 1965 Switzerland 1 7696/65 effect a high-Speed whirling or fluffing of the Particles and, at the same time, to impart a positive downward movement [52] US.
- This invention generally relates to a method and apparatus for continuously producing chemical solutions and suspensions and particularly concerns a method and apparatus wherein a continuous dissolving process is carried out with those materials wherein difficulties previously have been experienced in overcoming agglomerate formation between the solid and the solvent and wherein the solvent tended to form a jellylike skin which had to be rubbed off so as to expose new particle surfaces for the solvent penetration.
- an additional object of the instant invention concerns the provision of a new and improved method and apparatus of the type described which serves to prevent the formation of agglomerates and further serves to prevent the formation of a jellylike skin by the solvent over the solid solute particles.
- Another significant object of the instant invention concerns the provision of a new and improved method and apparatus of the described general type which operates in an efiicient and highly economical fashion.
- novel invention takes the form of both a method and apparatus operative to continuously produce chemical solutions and suspensions.
- the novel invention is characterized by the features that the solid particles are whirled at high speed and are fiuffed while, at the same time, a positive downward movement is imparted thereto.
- the solvent is sprayed into the whirling mass at stepwise, spaced locations along the direction of movement of the mass, which mass, now fully wetted, is subsequently mildly continuously agitated and kneaded at a relatively low speed for a length of time corresponding to the time required for the dissolving or suspension reactions to complete.
- the difference in speed between the high-speed whirling or fluffing procedure and the low-speed continuous mild agitation and kneading represents a 66.6 multiple although at least a tenfold multiple has been found to be sufficient.
- the novel apparatus for carrying out the method above discussed is contemplated to comprise a continuous kneader means operating at a given relatively low r.p.m. such as 45 r.p.m., for example.
- a continuous mixer means is disposed upstream of the kneader means and serves to form a solution free from agglomerates of solids and liquids and serves to feed the solution to the kneader means.
- Separate inlet means are associated with the mixer means and serve to deliver the solids and liquids to the mixer means with the mixer means, in the preferred embodiment, comprising a housing and a shaft disposed within the housing, the shaft incorporating a plurality of mixing and comminuting elements spaced along the length thereof.
- means for driving the shaft at a considerably higher multiple r.p.m. than the rpm. of the kneader means are provided such that the solids and liquids fed thereto are rapidly whirled and such that the solids are, in fact, fluffed.
- such shaft is contemplated to be driven at approximately 3,000 rpm.
- the preferred arrangement or apparatus for continuously producing solutions or suspensions will be seen to comprise a continuous kneader 1 having a housing 2 in which is disposed a rotatable worm 3 driven at a relatively low r.p.m., such as 45 r.p.m., for example, by means of a motor 4 and suitable adjustable gearing disposed in housing 4.
- a high-speed mixer 5 is provided and has a discharge opening 6 coupled with the feed opening of the housing 2 of the continuous kneader 1.
- the high-speed mixer incorporates a vertical housing 7 in which a shaft 8 is disposedv
- shaft 8 incorporates a series of mixing and comminuting elements 9 spaced along the shaft length and which project radially outward therefrom.
- An electric motor 10 is provided and is coupled with the end of the shaft extending above the top end of a housing 7, electric motor 10 driving the shaft at a relatively high speed, such as 3,000 rpm, for example. Accordingly, the rpm. of shaft 8 thus comprises a considerably higher multiple than that of the worm 3 and, in the example given, will be seen to turn 66.6 times faster than the worm although at least a tenfold multiple has been found to be suitable.
- the solid matter or solute which is to be dissolved in the liquid or solvent is initially contained in a hopper l1 and is delivered, in metered amounts, to an inlet 13 disposed in the upper portion of the mixer by means of an endless belt or weigh feeder 12.
- the solid matter which at this time has become pulverized is engaged by the winglike mixing and comminuting elements 9 and specifically is initially. engaged by the comminuting element provided on the shaft in the region of the inlet opening. Due to the high speed of revolution of the shaft 8, the solid matter is caused to be rapidly whirled or rotated and actually fluffed whereby relatively loose agglomerates of the solid or solute are broken up. At the same time, the fluffed, rapidly whirling particles have a positive downward movement imparted thereto due to the combined effect of gravitational force and the construction of the mixing and comminuting elements 9.
- Liquid or solvent is delivered from a container 14 through a feedpipe l5 and dosing or metering pump 17 to the vertical housing 7 of the mixer.
- feedpipe 15 has a plurality of outlets stepwise spaced along the circumference of housing 7 in the direction of downward movement of the whirling particles.
- the discharge of the liquid or solvent in this fashion into the whirling mass serves to fully wet the mass as the whirling mass is positively, or under gravitational force, driven downwardly.
- the inside surface of the walls of housing 7 is preferably provided with stationary elements 16 having a wedgelike cross section, these stationary elements cooperating with the mixing and comminuting elements 9.
- the wetted mass or mixture enters the continuous kneader 1 through discharge opening 6 of the mixer housing 7 and such mixture can be further processed without difficulty.
- the wetted mass is mildly but continuously agitated and kneaded with a dwell time corresponding to the time required for the dissolving or suspension reactions to complete.
- a dwell time corresponding to the time required for the dissolving or suspension reactions to complete.
- housing 7 preferably has a separate inlet for each of the substances to be mixed together.
- the above-described arrangement is, for example, particularly suitable for dissolving polyacrylo nitrile in dimethylformamide, acetyl cellulose in acetone, PVC in cycle-hexanone, for example, and for producing suspensions from terephthalic acid and glycol, for example, whereby the time that the product is in the arrangement for continuously producing solutions and suspensions as against that spent in a batch operating arrangement, is appreciably shorter.
- the quality of the product is improved and, when dissolving polyacrylo nitrile in dimethylformamide, for example, the yellowing which otherwise appears, is greatly reduced or even altogether eliminated.
- the resulting spinning solution was seen to have optimum light color and clarity and was free of any gel particles rendering a final product having the desired properties.
- the polyacrylo nitrile polymer in the form of a very fine powder having a tendency to shooting and bridging was continuously proportioned at a rate of approximately 200 kg./hr. into the inlet 13 of the high-speed mixer 5 wherein it was fluffed and whirled and given a downward feed by the mixing and comminuting member 9' in the inlet throat. 800 kg./hr. of the solvent was stepwise added through the spray nozzles 15.
- the high-speed mixer was driven at a rate of 3,000 r.p.m. and the material rapidly passing through was instantaneously dissolved with the product temperature rising from the ambient only to about 40 C.
- the housing 7 of the high-speed mixer 5, in this exemplary operation was cooled by water at ambient temperature and it was noted that the absorbed power was only approximately 10 hp.
- the dissolved product then passed into the continuous kneader 1 through the discharge opening 6 of the high-speed mixer 5 and entered such kneader at the rate of 1,000 kg./hr.
- the dissolved product in this exemplary arrangement was slightly heated to below C. and was agitated for the stabilization of the solution.
- the kneader pocket and the internal worm or screw l preferably was heated to C. from an external steam supp y and the screw was run at 42 r.p.m.
- a method for continuously producing chemical solutions and suspensions comprising the steps of:
- delivering into a mixer means a metered dose of solid solute particles in a finely comminuted condition
- said first speed at which said particles are whirled being at least 10 times greater than said second speed at which the wetted further comminuted agglomerates are mildly continuously agitated and kneaded;
Abstract
A novel method and apparatus for continuously producing chemical solutions and suspensions is disclosed. The novel invention serves to effect a continuous dissolving process of a chemical solute in a solvent and does so in a fashion which prevents the formation of agglomerates and jellylike skin on the particles and serves to dissolve or suspend such materials without introducing high sheer force into the product. In a preferred embodiment, the novel invention contemplates to effect a high-speed whirling or fluffing of the particles and, at the same time, to impart a positive downward movement thereto. The solvent is then sprayed into the whirling mass at different stepwise spaced locations along the direction of downward movement of the particles, which particles or mass, now full wetted, are then continuously agitated at a relatively low speed providing mild agitation and kneading and a dwell time sufficient for the time required for the dissolving or suspension reactions to complete.
Description
United States Patent Gresch et a1. Mar. 7, 1972 [54] METHOD AND APPARATUS FOR [56] References Cited CONTINUOUSLY PRODUCING SOLUTIONS AND SUSPENSIONS UNTED STATES PATENTS Inventors: Walter Gresch Muttenz; Horst Pilch Pm 3,160,352 12/1964 Mollrmg ..241/98 :13; nlilrwm Ruttener, Rihen, all of Swit- Primary Examiner Theodore M orris Attorney- Jacobi, Davidson & Kleeman [73] Assignee: Buss AG, Basel, Switzerland 221 Filed: Nov. 12,1969 [57] ABSIMCT I A novel method and apparatus for continuously producing [21] App! 875962 chemical solutions and suspensions is disclosed. The novel in- Rehned s Appucafion Data vention serves to effect a continuous dissolving process of a chemical solute in a solvent and does so in a fashion which [63] commuatlonm'part of 5 prevents the formation of agglomerates and jellylike skin on 1966- the particles and serves to dissolve or suspend such materials without introducing high sheer force into the product. In a [30] Formal Apphcauon Pnonty Dam preferred embodiment, the novel invention contemplates to Dec. 20, 1965 Switzerland 1 7696/65 effect a high-Speed whirling or fluffing of the Particles and, at the same time, to impart a positive downward movement [52] US. Cl ..l06/l87, 106/198, 260/326, thereto- Th S lv nt is then sprayed into the whirling mass at 260/32.8,260/34.2 different stepwise spaced locations along the direction of [51] Int. Cl. ..C08b 27/48 downward movement of the particles, which particles or m [58] Field of Search ..241/l2, 16; 260/342; 106/187, now full wetted, are then continuously agitated at a relatively 106/ 198 low speed providing mild agitation and kneading and a dwell time sufficient for the time required for the dissolving or suspension reactions to complete.
3 Claims, 1 Drawing Figure PAIENTEDMAR 7:912
S E R N 03 F. E T N Gum v WEN URW AOR WHE METHOD AND APPARATUS FOR CONTINUOUSLY PRODUCING SOLUTIONS AND SUSPENSIONS This application is a continuation-in-part of application Ser. No. 600,538, filed Dec. 9, 1966.
BACKGROUND OF THE INVENTION This invention generally relates to a method and apparatus for continuously producing chemical solutions and suspensions and particularly concerns a method and apparatus wherein a continuous dissolving process is carried out with those materials wherein difficulties previously have been experienced in overcoming agglomerate formation between the solid and the solvent and wherein the solvent tended to form a jellylike skin which had to be rubbed off so as to expose new particle surfaces for the solvent penetration.
Continuous dissolving processes of the general type above described have been carried out in the prior art by means of the employment of screw extruders and the like. Yet, it has been found that with such prior art techniques and associated apparatus, a significant disadvantage occurs in that when dosing the particles to be dissolved or suspended, large agglomerates oftentimes form in the vicinity of the feed inlet. These agglomerates were enveloped by solvent and a jellylike skin formed over the agglomerates which hindered further dissolving. Thus, the jellylike skin of the agglomerates had to be rubbed off so as to expose a new surface for the penetration of the solvent and, to rub off such skin, relatively large sheer forces had to be provided which required complicated apparatus oftentimes utilizing special abrading elements. The same difficulties were seen to arise in the prior art when suspensions rather than solutions were produced in accordance with the prior art techniques. As a result, such prior art techniques were highly inefficient and the apparatus required to carry out such techniques were expensive, required relatively high operational power and generally were uneconomical.
SUMMARY OF THE INVENTION Thus, a need exists in the art for a new and improved method as well as apparatus for continuously producing chemical solutions and suspensions in a manner eliminating the disadvantageous aspects associated with prior art techniques and devices. It is a primary object of the instant invention to provide such a new and improved method and apparatus.
Further, more specific yet equally important objects of the instant invention concern the provision of a novel method and apparatus which continuously produces solutions and suspensions, which method and apparatus operates without the necessity of introducing high sheer forces into the product. An additional object of the instant invention concerns the provision of a new and improved method and apparatus of the type described which serves to prevent the formation of agglomerates and further serves to prevent the formation of a jellylike skin by the solvent over the solid solute particles. Another significant object of the instant invention concerns the provision of a new and improved method and apparatus of the described general type which operates in an efiicient and highly economical fashion.
These objects as well as other objects which will become apparent as the description proceeds, are implemented by the novel invention which takes the form of both a method and apparatus operative to continuously produce chemical solutions and suspensions. The novel invention is characterized by the features that the solid particles are whirled at high speed and are fiuffed while, at the same time, a positive downward movement is imparted thereto. Now, the solvent is sprayed into the whirling mass at stepwise, spaced locations along the direction of movement of the mass, which mass, now fully wetted, is subsequently mildly continuously agitated and kneaded at a relatively low speed for a length of time corresponding to the time required for the dissolving or suspension reactions to complete. In the preferred inventive embodiment, the difference in speed between the high-speed whirling or fluffing procedure and the low-speed continuous mild agitation and kneading represents a 66.6 multiple although at least a tenfold multiple has been found to be sufficient.
The novel apparatus for carrying out the method above discussed is contemplated to comprise a continuous kneader means operating at a given relatively low r.p.m. such as 45 r.p.m., for example. A continuous mixer means is disposed upstream of the kneader means and serves to form a solution free from agglomerates of solids and liquids and serves to feed the solution to the kneader means. Separate inlet means are associated with the mixer means and serve to deliver the solids and liquids to the mixer means with the mixer means, in the preferred embodiment, comprising a housing and a shaft disposed within the housing, the shaft incorporating a plurality of mixing and comminuting elements spaced along the length thereof. Finally, means for driving the shaft at a considerably higher multiple r.p.m. than the rpm. of the kneader means are provided such that the solids and liquids fed thereto are rapidly whirled and such that the solids are, in fact, fluffed. In the preferred inventive embodiment, such shaft is contemplated to be driven at approximately 3,000 rpm.
BRIEF DESCRIPTION OF THE DRAWING The invention itself both from its method as well as apparatus aspects, will be better understood and further features and advantages thereof will become apparent when attention is given the following detailed description of a preferred inventive arrangement, such description referring to the appended single sheet of drawing wherein the sole FIGURE thereon schematically depicts an elevational view, partially in cross section, of a novel apparatus suitable for carrying out the novel improved method.
DETAILED DESCRIPTION OF THE PREFERRED INVENTIVE EMBODIMENT Now, by referring to the drawing, the detailed structure of the novel apparatus will be apparent and, by an understanding of such apparatus and the operation thereof, the novel features of the improved method for continuously producing solutions and suspensions will be appreciated.
The preferred arrangement or apparatus for continuously producing solutions or suspensions will be seen to comprise a continuous kneader 1 having a housing 2 in which is disposed a rotatable worm 3 driven at a relatively low r.p.m., such as 45 r.p.m., for example, by means of a motor 4 and suitable adjustable gearing disposed in housing 4.
A high-speed mixer 5 is provided and has a discharge opening 6 coupled with the feed opening of the housing 2 of the continuous kneader 1. The high-speed mixer incorporates a vertical housing 7 in which a shaft 8 is disposedv As is illustrated, shaft 8 incorporates a series of mixing and comminuting elements 9 spaced along the shaft length and which project radially outward therefrom. An electric motor 10 is provided and is coupled with the end of the shaft extending above the top end of a housing 7, electric motor 10 driving the shaft at a relatively high speed, such as 3,000 rpm, for example. Accordingly, the rpm. of shaft 8 thus comprises a considerably higher multiple than that of the worm 3 and, in the example given, will be seen to turn 66.6 times faster than the worm although at least a tenfold multiple has been found to be suitable.
The solid matter or solute which is to be dissolved in the liquid or solvent is initially contained in a hopper l1 and is delivered, in metered amounts, to an inlet 13 disposed in the upper portion of the mixer by means of an endless belt or weigh feeder 12. The solid matter which at this time has become pulverized is engaged by the winglike mixing and comminuting elements 9 and specifically is initially. engaged by the comminuting element provided on the shaft in the region of the inlet opening. Due to the high speed of revolution of the shaft 8, the solid matter is caused to be rapidly whirled or rotated and actually fluffed whereby relatively loose agglomerates of the solid or solute are broken up. At the same time, the fluffed, rapidly whirling particles have a positive downward movement imparted thereto due to the combined effect of gravitational force and the construction of the mixing and comminuting elements 9.
Liquid or solvent is delivered from a container 14 through a feedpipe l5 and dosing or metering pump 17 to the vertical housing 7 of the mixer. In the preferred inventive embodiment as is illustrated, feedpipe 15 has a plurality of outlets stepwise spaced along the circumference of housing 7 in the direction of downward movement of the whirling particles. The discharge of the liquid or solvent in this fashion into the whirling mass serves to fully wet the mass as the whirling mass is positively, or under gravitational force, driven downwardly. To reinforce the agglomerate breaking action, the inside surface of the walls of housing 7 is preferably provided with stationary elements 16 having a wedgelike cross section, these stationary elements cooperating with the mixing and comminuting elements 9.
Now, the wetted mass or mixture enters the continuous kneader 1 through discharge opening 6 of the mixer housing 7 and such mixture can be further processed without difficulty. Specifically, while in the continuous kneader, the wetted mass is mildly but continuously agitated and kneaded with a dwell time corresponding to the time required for the dissolving or suspension reactions to complete. This is a generally wellknown dwell time requirement even for fully wetted particles with complete solvent penetration where, in many cases, materials will pass through intermediate physical stages of gel formation with higher viscosity and where some mild kneading is sufficient, provided no undissolved particle agglomerates are present. As a further advantageous feature, housing 7 preferably has a separate inlet for each of the substances to be mixed together.
The above-described arrangement is, for example, particularly suitable for dissolving polyacrylo nitrile in dimethylformamide, acetyl cellulose in acetone, PVC in cycle-hexanone, for example, and for producing suspensions from terephthalic acid and glycol, for example, whereby the time that the product is in the arrangement for continuously producing solutions and suspensions as against that spent in a batch operating arrangement, is appreciably shorter. As a consequence, the quality of the product is improved and, when dissolving polyacrylo nitrile in dimethylformamide, for example, the yellowing which otherwise appears, is greatly reduced or even altogether eliminated.
In one particular preferred process wherein clear spinning solutions of polyacrylo nitrile in dimethylformamide as solvent was produced, the resulting spinning solution was seen to have optimum light color and clarity and was free of any gel particles rendering a final product having the desired properties.
The polyacrylo nitrile polymer, in the form of a very fine powder having a tendency to shooting and bridging was continuously proportioned at a rate of approximately 200 kg./hr. into the inlet 13 of the high-speed mixer 5 wherein it was fluffed and whirled and given a downward feed by the mixing and comminuting member 9' in the inlet throat. 800 kg./hr. of the solvent was stepwise added through the spray nozzles 15. The high-speed mixer was driven at a rate of 3,000 r.p.m. and the material rapidly passing through was instantaneously dissolved with the product temperature rising from the ambient only to about 40 C. The housing 7 of the high-speed mixer 5, in this exemplary operation, was cooled by water at ambient temperature and it was noted that the absorbed power was only approximately 10 hp.
The dissolved product then passed into the continuous kneader 1 through the discharge opening 6 of the high-speed mixer 5 and entered such kneader at the rate of 1,000 kg./hr. At this time, the dissolved product in this exemplary arrangement, was slightly heated to below C. and was agitated for the stabilization of the solution. The kneader pocket and the internal worm or screw lpreferably was heated to C. from an external steam supp y and the screw was run at 42 r.p.m.
absorbing 32 hp. The average processing time from feeding the dry and liquid components into the apparatus to the time that the clear spinning solution left the kneader was approximately 3 minutes.
As should now be apparent, the objects initially set forth at the outset of the specification have been successfully achieved. Accordingly,
What is claimed is:
l. A method for continuously producing chemical solutions and suspensions, such method comprising the steps of:
delivering into a mixer means a metered dose of solid solute particles in a finely comminuted condition;
fluffing the solid finely comminuted particles by whirling same at a first speed and imparting to the solid particles a positive downward movement; introducing a metered dose of solvent into the whirling, downwardly moving, finely comminuted particles whereby the whirling mass is wetted only to the extent that there are formed loose agglomerates of such particles; further whirling the wetted loose agglomerates and in such condition further comminuting the, loose agglomerates;
said first speed at which said particles are whirled being at least 10 times greater than said second speed at which the wetted further comminuted agglomerates are mildly continuously agitated and kneaded;
then mildly continuously agitating and kneading the wetted further comminuted agglomerates at a second speed considerably lower than said first speed and for a given dwell time; and
discharging the product.
2. A method as defined in claim 1, including the step of introducing the metered dose of solvent at a plurality of locations along the path of downward movement of the whirling mass.
3. A method as defined in claim 2, including the step of mixing and comminuting the downwardly moving whirling mass during such time as the metered dose of solvent is introduced therein.
Claims (2)
- 2. A method as defined in claim 1, including the step of introducing the metered dose of solvent at a plurality of locations along the path of downward movement of the whirling mass.
- 3. A method as defined in claim 2, including the step of mixing and comminuting the downwardly moving whirling mass during such time as the metered dose of solvent is introduced therein.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1769665A CH437217A (en) | 1965-12-20 | 1965-12-20 | Device for the continuous production of solutions and suspensions |
Publications (1)
Publication Number | Publication Date |
---|---|
US3647493A true US3647493A (en) | 1972-03-07 |
Family
ID=4427386
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US875962A Expired - Lifetime US3647493A (en) | 1965-12-20 | 1969-11-12 | Method and apparatus for continuously producing solutions and suspensions |
Country Status (8)
Country | Link |
---|---|
US (1) | US3647493A (en) |
AT (1) | AT274742B (en) |
BE (1) | BE691483A (en) |
BR (1) | BR6685479D0 (en) |
CH (1) | CH437217A (en) |
FR (1) | FR1506697A (en) |
NL (1) | NL6617778A (en) |
SE (1) | SE334143B (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2398774A1 (en) * | 1977-07-26 | 1979-02-23 | Akzona Inc | PROCESS FOR PREPARING A SOLUTION OF CELLULOSE IN A TERTIARY AMINE OXIDE |
US4211574A (en) * | 1977-07-26 | 1980-07-08 | Akzona Incorporated | Process for making a solid impregnated precursor of a solution of cellulose |
US4778835A (en) * | 1985-12-09 | 1988-10-18 | Eastman Kodak Company | Process and apparatus for preparing polyester dissipations |
US5609831A (en) * | 1992-08-20 | 1997-03-11 | Bernhard Rustige Gmbh & Co. Kommanditgesellschaft | Machine for producing a cross-linked extruded product |
EP1110690A2 (en) * | 1999-12-21 | 2001-06-27 | General Electric Company | Continuous preparation of heat-vulcanizable silicone compositions |
EP2446957A3 (en) * | 2005-09-28 | 2012-08-22 | China Tobacco Hunan Industrial Corporation | Devices for adding tobacco dust into paper making tobacco sheet |
US20130126647A1 (en) * | 2010-05-21 | 2013-05-23 | Charles Allen Arnold | Comminution Reactor |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2701542C2 (en) * | 1977-01-15 | 1985-09-12 | Dietrich Dipl.-Ing. 6240 Königstein Maurer | Device for the continuous production and delivery of a mixture of a granular or powdery, dry solid and a liquid |
US4428852A (en) * | 1982-01-18 | 1984-01-31 | E. I. Du Pont De Nemours And Company | Continuous synthesis of chromium dioxide |
PL142347B1 (en) * | 1984-02-28 | 1987-10-31 | Biuro Studiow I Projektow Energetycznych "Energoprojekt" | Flow-through mixer |
DE3601324A1 (en) * | 1986-01-17 | 1987-07-23 | Wacker Chemie Gmbh | METHOD FOR THE CONTINUOUS PRODUCTION OF SILICONE MATERIALS VULCANIZABLE AT ROOM TEMPERATURE |
DE4027888A1 (en) * | 1990-09-03 | 1992-03-05 | Stoess & Co Gelatine | METHOD FOR CONTINUOUSLY RELEASING GELATINE |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3160352A (en) * | 1959-06-15 | 1964-12-08 | Gilman B Mollring | Apparatus for pulverizing and dispersing solid material into liquid suspension |
-
1965
- 1965-12-20 CH CH1769665A patent/CH437217A/en unknown
-
1966
- 1966-12-12 SE SE16966/66A patent/SE334143B/xx unknown
- 1966-12-13 AT AT1147566A patent/AT274742B/en active
- 1966-12-16 FR FR87812A patent/FR1506697A/en not_active Expired
- 1966-12-19 BR BR185479/66A patent/BR6685479D0/en unknown
- 1966-12-19 NL NL6617778A patent/NL6617778A/xx unknown
- 1966-12-20 BE BE691483D patent/BE691483A/xx unknown
-
1969
- 1969-11-12 US US875962A patent/US3647493A/en not_active Expired - Lifetime
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3160352A (en) * | 1959-06-15 | 1964-12-08 | Gilman B Mollring | Apparatus for pulverizing and dispersing solid material into liquid suspension |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2398774A1 (en) * | 1977-07-26 | 1979-02-23 | Akzona Inc | PROCESS FOR PREPARING A SOLUTION OF CELLULOSE IN A TERTIARY AMINE OXIDE |
US4144080A (en) * | 1977-07-26 | 1979-03-13 | Akzona Incorporated | Process for making amine oxide solution of cellulose |
US4211574A (en) * | 1977-07-26 | 1980-07-08 | Akzona Incorporated | Process for making a solid impregnated precursor of a solution of cellulose |
US4778835A (en) * | 1985-12-09 | 1988-10-18 | Eastman Kodak Company | Process and apparatus for preparing polyester dissipations |
US5609831A (en) * | 1992-08-20 | 1997-03-11 | Bernhard Rustige Gmbh & Co. Kommanditgesellschaft | Machine for producing a cross-linked extruded product |
EP1110690A2 (en) * | 1999-12-21 | 2001-06-27 | General Electric Company | Continuous preparation of heat-vulcanizable silicone compositions |
EP1110690A3 (en) * | 1999-12-21 | 2002-03-20 | General Electric Company | Continuous preparation of heat-vulcanizable silicone compositions |
US6414054B1 (en) | 1999-12-21 | 2002-07-02 | General Electric Company | Continuous preparation of heat-vulcanizable silicone compositions |
US20020136085A1 (en) * | 1999-12-21 | 2002-09-26 | Jodi Boffard | Continuous preparation of heat-vulcanizable silicone compositions |
US20040257905A1 (en) * | 1999-12-21 | 2004-12-23 | Jodi Boffard | Continuous annular layer mixer |
US6913380B2 (en) | 1999-12-21 | 2005-07-05 | General Electric Company | Continuous preparation of heat-vulcanizable silicone compositions |
US7178973B2 (en) | 1999-12-21 | 2007-02-20 | General Electric Company | Continuous annular layer mixer |
EP2446957A3 (en) * | 2005-09-28 | 2012-08-22 | China Tobacco Hunan Industrial Corporation | Devices for adding tobacco dust into paper making tobacco sheet |
US20130126647A1 (en) * | 2010-05-21 | 2013-05-23 | Charles Allen Arnold | Comminution Reactor |
Also Published As
Publication number | Publication date |
---|---|
BE691483A (en) | 1967-05-29 |
SE334143B (en) | 1971-04-19 |
CH437217A (en) | 1967-06-15 |
BR6685479D0 (en) | 1973-12-27 |
AT274742B (en) | 1969-09-25 |
NL6617778A (en) | 1967-06-21 |
FR1506697A (en) | 1967-12-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3647493A (en) | Method and apparatus for continuously producing solutions and suspensions | |
US3744763A (en) | Apparatus for producing emulsions or suspensions | |
AT402410B (en) | METHOD FOR PRODUCING A CELLULOSE SUSPENSION | |
US4788230A (en) | Process for making a low density syntactic foam product and the resultant product | |
EP1792643B1 (en) | High volume reactor and/or thin film evaporator employing a premixing device | |
US5368385A (en) | Continuous solution method and apparatus | |
US3510067A (en) | Method and device for converting thermoplastic foil waste to a flowable granular material | |
US3568940A (en) | Coaxial disc refining apparatus for reclaiming rubber scrap | |
US4698378A (en) | Procedure for the continuous production of free flowing and homogenous mixtures of plastic materials with admixtures | |
RU2215724C2 (en) | Method of production of spherical particles of energy-giving compounds | |
US2584225A (en) | Mixing apparatus | |
US3308171A (en) | Method for producing granular or powdery sorbitol from sorbitol solution | |
US3460769A (en) | Method and apparatus for reclaiming rubber scrap | |
US3271194A (en) | Solidification of saccharide solutions | |
CN100344664C (en) | Process for producing polyurethane foam | |
US3643874A (en) | Process for the preparation of intermediates of polyaddition resins | |
US3734415A (en) | Apparatus for the preparation of solid intermediates of polyaddition resins in the form of connected pieces useful for breaking and grinding | |
RU2515293C1 (en) | Method of granulating particulates | |
JPH0273869A (en) | Method for conversion of crude copper phthalocyanine into pigment form | |
JPH059456B2 (en) | ||
DE3125396A1 (en) | Process for dispersing granular or powdered solids with liquid components | |
EP1417998A1 (en) | Mixing device | |
US1225129A (en) | Process of mixing cement mortar. | |
CH381415A (en) | Process for the preparation of mixtures of thermoplastic polymers and plasticizers | |
US1778193A (en) | Mixing apparatus |