US3678983A - Thin film apparatus - Google Patents

Thin film apparatus Download PDF

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Publication number
US3678983A
US3678983A US44197A US3678983DA US3678983A US 3678983 A US3678983 A US 3678983A US 44197 A US44197 A US 44197A US 3678983D A US3678983D A US 3678983DA US 3678983 A US3678983 A US 3678983A
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US
United States
Prior art keywords
rotor
thin film
compartment
ring members
film apparatus
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
Application number
US44197A
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English (en)
Inventor
Fritz Widmer
Janos Miklos Gorbei
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Luwa Ltd
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Luwa Ltd
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Publication date
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D1/00—Evaporating
    • B01D1/22—Evaporating by bringing a thin layer of the liquid into contact with a heated surface
    • B01D1/222—In rotating vessels; vessels with movable parts
    • B01D1/223—In rotating vessels; vessels with movable parts containing a rotor
    • B01D1/225—In rotating vessels; vessels with movable parts containing a rotor with blades or scrapers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D1/00—Evaporating
    • B01D1/30—Accessories for evaporators ; Constructional details thereof
    • B01D1/305—Demister (vapour-liquid separation)

Definitions

  • Kleeman 5 ABSTRACT A thin film apparatus of the type embodying an approximately vertical treatment compartment or chamber and with which merges at the upper end thereof a separation compartment possessing a rotor equipped with vanes or blades as well as two ring members which are spaced in axial direction from one another.
  • the ring members surround the cross section of the separation compartment which is swept over by the rotor.
  • Radially extending droplet collecting ridges, grooves or the like are provided at the aforementioned rotor blades or vanes, these droplet collecting ridges opening between both of the ring members.
  • the ring members are rigidly connected for rotation with the vane rotor and possess an internal diameter which essentially corresponds to the diameter of the rotor, and furthermore, the ring members partially bound the liquidthroughpassage means disposed externally of the rotor.
  • the present invention relates to a new and improved construction of thin film apparatus of the type comprising an approximately vertically disposed treatment compartment or chamber and a separation compartment or chamber which merges with the upper end of the treatment compartment, this separation chamber containing a rotor equipped with blades or vanes.
  • the prior art is already familiar with a thin film evaporator embodying a vertically disposed, rotationally symmetrical evaporation compartment. At the upper end of the evaporation compartment there merges a separation compartment.
  • a shaft extends substantially coaxially with respect to said separation-and evaporation compartments.
  • a number of suitable vanes or blade members are attached to this shaft and extend axially over the length of the separation compartment and the evaporation compartment, these blades also extending radially up to the region of the inner wall of the evaporation compartment.
  • An annular compartment is provided between the separation chamber or compartment wall and the rotor vane extremities, a substantially ring-shaped disc member being secured in this annular compartment to the separation chamber wall at the region of the vanes.
  • a second substantially ring-shaped disk member is secured to the wall of the separation chamber directly above the upper ends of the vanes. Between these disk members there are secured to the inner separation chamber wall a number of axially extending vane portions which also extend radially up to the region of the rotor vanes.
  • vanes secured to the separation chamber wall between the two ring disk members have the function of acting upon the vapor currents departing from the region of the rotating vanes and which have imparted thereto a rotational movement and to deflect such vapor currents so as to partake in an axial directed movement in a direction towards the vapor discharge connection.
  • the separated droplets flow along the vapor chamber wall towards the evaporation chamber and are dammed up by the ring disks arranged at the separation chamber wall, from which location they can drop into the evaporation compartment.
  • a major drawback of this type droplet separator is the fact that the separated droplets which are to be returned into the evaporation chamber must penetrate through the ascending vapor current a number of times approximately at right angles. Hence, it is impossible to prevent the vapors which are flowing towards the vapor discharge connection from at least partially again entraining the downwardly falling droplets. Hence, the upperwardly directed vapor stream tends to remove these entrained droplets from the operable region of the droplet separator, and consequently, the withdrawn vapors are charged with particles of the material to be treated. This liquid component must then be either removed externally of the thin film apparatus by a separator from the vapors, or it can be conveyed away together with the vapors. In each situation, there cannot be avoided a more expensive processing of the material which is to be concentrated through the action of the thin film apparatus, because the efficiency of the thin film apparatus is reduced, or however, there must be taken into account a considerable loss of otherwise useful material.
  • Another noteworthy object of the present invention is to provide an improved thin film apparatus which provides for more economical material processing.
  • Still a further significant object of the present invention relates to an improved thin film apparatus which substantially minimizes the loss of droplets of the material being treated by minimizing entrainment thereof by the vapor stream departing from the system.
  • Still a further noteworthy object of the present invention relates to an improved thin film apparatus for the treatment of materials which is relatively simple in construction, extremely economical to manufacture, provides for improved economy in the treatment operation, is not readily subject to breakdown, and is easy to service.
  • the invention is predicated upon the recognition that in order to achieve a good efficiency of the separator it is less important to attain a practically complete first separation of all liquid droplets through multiple deflection of the vapor-or gas stream, which can be associated with considerably pressure losses; rather it is more important to prevent the separated liquid from again being entrained by the vapor-or gas stream.
  • the invention contemplates a thin film apparatus construction wherein the ring members are rigidly connected for rotation with the rotor equipped with blades or vanes, and furthermore, that such ring members possess an internal diameter which is approximately equal to the diameter of the rotor, and further, wherein such ring members partially bound the liquid-throughpassages or openings situated externally of the rotor construction.
  • FIG. 1 is an elevational sectional view of a preferred embodiment of inventive thin film evaporator equipped with a droplet separator;
  • FIG. 2 is a cross-sectional view of the thin film evaporator depicted in FIG. 1, taken substantially along the line Illl thereof;
  • FIG. 3 is an enlarged fragmentary view of a modified construction of droplet separator for use in the thin film evaporator construction of FIG. 1;
  • FIG. 4 is a similar enlarged fragmentary view of a still further variant construction of droplet separator for use in the thin film evaporator structure of FIG. 1.
  • FIGS. 1 and 2 reference numeral generally designates an approximately vertically arranged, rotationally symmetrical thin film evaporator embodying a housing 100 which is subdivided into a lower evaporation compartment or chamber 12 and a vapor compartment or chamber 14 arranged above this evaporation chamber 12.
  • the vapor compartment 14 defines an axial extension of the evaporation chamber 12.
  • the upper end of the vapor compartment or chamber 14 is sealed by a cover member 16, while the lower end of the evaporation compartment 12 is sealed by a conical member 18 which, in turn, opens into a discharge or outlet connection 20.
  • a suitable heating jacket 26 which encloses the confines of the evaporation chamber 12.
  • a material inlet opening or connection 22 is provided at the region of the vapor compartment 14 at the wall of the evaporation compartment or chamber 12. Further more, the wall of the vapor compartment 14 is equipped with a vapor discharge conduit 24 directly below the cover member 16.
  • a rotor construction is arranged coaxially with respect of the vapor compartment 14 and the evaporation compartment 12.
  • This rotor means or construction 32 will be seen to embody a central tubular body 34, the upper end of which is equipped with a shaft stub or journal 36 and by means of this journal is rotatably mounted at a suitable bearing 38 provided at the cover member 16.
  • the lower end of this tubular body or shaft 34 likewise has a shaft stub or journal 40 which is supported in a bearing 42.
  • Bearing 42 is retained by a plurality of supports 44 mounted coaxially within the conical portion 18.
  • a number or axially extending wiper vanes or blades 46 which also extend radially up to the region of the inner wall of the evaporation chamber 12.
  • a droplet separator construction generally designated by reference character 48.
  • This droplet separator 48 embodies a plurality of droplet separator blades or vanes 50 which extend axially between the evaporation chamber 12 and the vapor discharge conduit 24. Separator vanes 50 also extend radially towards the inner wall of the associated vapor compartment or chamber 14 and terminate at a spacing therefrom.
  • the star-shaped configuration of these separator vanes 50 which are arranged at the tubular body or shaft 34 are surrounded at their upper and lower ends by a respective substantially ring-shaped disk member 52 and 54.
  • ringshaped disk members 52 and 54 respectively, partially delimit or bound in axial direction the free space appearing between the wall of the vapor chamber 14 and the separator vanes or blades 50. Furthermore, it is also possible, depending upon the axial extent of the droplet separator 48, to provide over the length of the separator vanes 50 more than two such ringshaped disk members which, for instance, are arranged at an equal spacing from one another. Furthermore, viewed in the direction of rotation of the rotor 32, there are arranged at the front side or face of the separator vanes or blades 50 at an a plurality of droplet collecting ridges or depressions 56 which extend radially along the entire width of each associated separator vane 50. The rotor 32 is connected in driving relationship via the shaft stub 36 with a suitable drive motor 58 or any other suitable prime mover.
  • the material which is to be concentrated is introduced through the inlet connection 22 into the evaporation compartment 12 heated by the heating jacket 26.
  • the wiper blades 46 rotating within the evaporation compartment 12 distribute the material to be concentrated in the form of a thin film onto the inner wall of the evaporation compartment 12. Due to the action of gravity the thin film of material tends to flow towards the discharge or outlet connection 20.
  • the vapors, resulting from concentration of the material flow in counter current to the aforementioned thin layer or film, towards the vapor chamber or compartment 14, where they are conducted through the droplet separator unit 48.
  • the thus cleaned vapors are guided through the vapor discharge connection 24 to a nonillustrated condensor or other suitable piece of equipment, where they are condensed.
  • the vapor streams charged with droplets, and flowing towards the droplet separator 48, are deflected upon entry into such droplet separator, by the lower ring-shaped disk member 54 towards the center of the rotor unit 32.
  • the vapor current deflected at the region of the separator vanes 50 is engaged by these separator vanes 50, so that through the action of the centrifical forces the heavier droplets are separated at the vanes.
  • the vapors which flow through the droplet separator 48 have the tendency of entraining towards the vapor discharge connection 24 the droplets which have been separated out at the separator vanes or blades 50, However, to avoid or minimize such activity, the droplets, which have been collected by the collecting ridges 56 arranged at the front side of the separator vanes 50 in the direction of rotation of the rotor 32, are ejected by the action of the centrifical forces against the inner wall of the vapor compartment 14.
  • the radially directed vapor currents which exist by virtue of the rotation of the separator vanes or blades 50 flow through the axially directed currents which might still exist at the region of the free space between the inner wall of the vapor compartment 14 and the separator vanes 50.
  • the separated droplets flow under the action of gravity through the annular gap or throughpassage 72 formed between the ring-shaped disk member 54 and the inner wall of the vapor compartment 14 back, in countercurrent flow with respect to the vapors, into the evaporation compartment 12 where they can again admix with the new incoming material entering into the evaporation compartment 12 via the inlet connection or stud 22.
  • the droplet separator unit 48 By virtue of the previously described construction of the droplet separator unit 48, it is now possible to completely reclaim the liquid droplets entrained by the vapor currents, which not only enables dispensing with the use of a special separator outside of the thin film evaporator, rather also permits achieving an improved efficiency or degree of operation of the thin film evaporator. This is particularly then advantageous if expensive or relatively expensive materials are to be concentrated in the thin film evaporator.
  • FIG. 3 depicts a modified construction of droplet separator 48.
  • a plurality of separator vanes 50 are again arranged at the tubular body or shaft 34, each such vane or blade being equipped with two different types of droplet collecting ridges 66 and 68 respectively.
  • the droplet collecting ridges 66 are formed as recesses or depressions at the front face of the rotating separator vanes or blades 50
  • the other droplet collecting ridges 68 are constructed in the form of ledges disposed at the front face of each rotating separator vane 50.
  • the side of each ledge member 68 facing towards the evaporation compartment is equipped with a depression or ridge 70 which ensures for an improved withdrawal of the collected droplets.
  • the separator construction shown in this embodiment will be seen to have the ring-shaped disk members 60 and 60' which are arranged at the axial ends of the separator vanes 50 slotted at their periphery at least at one location, so that the thus formed marginal portions 62, 64 of the slotted location overlap one another, as shown.
  • These overlapping marginal portions 62, 64 of the annular or ring-shaped disks 60, 60 are flexed out of their plane in such a manner that they form a channel which is inclined in the direction of rotation of the droplet separator unit 48, with the inlet opening of such channel being disposed above the corresponding ring-shaped disk member 60 or 60 respectively.
  • the bent marginal portion 62 of the disk member 60 which extends upwardly at an inclination has the function of engaging the droplets collected directly above the corresponding ringshaped disk member 60 and to convey such below such ringshaped disk member
  • the inclined downwardly flexed marginal portion 64 of the ring-shaped disk member 60 has the function of imparting a movement component directed towards the evaporator compartment 12 to the droplets collected at the region of such marginal portion 64.
  • the lower ring-shaped disk member 60 is equipped with at least one such analogous opening or channel, whereby the function of this opening corresponds to that of the channel or opening described with respect to the ring-shaped disk member 60.
  • droplet separator 48 By virtue of this design of droplet separator 48 there is achieved that, apart from the gravitational forces which act upon the droplets, there is imparted particularly to the droplets collecting below the ring-shaped disk members 60 an additional component of movement so that there is achieved an improved return of the separated droplets.
  • the separator vanes or blades 74 are twice flexed or bent and form, as viewed in the axial extent of the droplet separator 48, a substantially zig-zag line.
  • the arrangement of separator vane 74 increases the separation effect of the droplet separator 48,
  • spiral 80 extends up to the direct region of the inner wall of the vapor compartment 14 in order to thus optimumly engage the separated liquid particles and to impart to such a component of movement which is directed towards the evaporation chamber 12.
  • the arrangement of a spiral 80 between the two ring-shaped disk members 78 and 78' furthermore has the advantage that the vapor rotating between the droplet separator 48 and the inner wall of the treatment chamber or compartment 14 has imparted to it a component of movement which is directed towards the evaporation compartment 12.
  • the droplet separator 48 possesses a greater rotational velocity than the vapor cushion between such droplet separator 48 and the inner wall of the vapor compartment 14, which, in turn, renders it possible to impart to the previously mentioned vapor cushion a component of movement which is directed in countercurrent to the vapors. Consequently, conditions can be obtained in the annular compartment which is partially bounded by the ring-shaped disk members 78 and 78' which ensure for an approximately percent return of the separated droplets.
  • a thin film apparatus comprising means providing a substantially vertically arranged material-treatment compartment which merges at its upper end with a droplet-separation compartment, rotor means equipped with blades provided for said separation compartment, at least two axially spaced ring members rigidly connected for rotation with said rotor means, said ring members encircling the cross-section of the separation compartment swept by said rotor means, substantially radially extending droplet collecting ridge means provided for said rotor blades and which open between said ring members, said ring members possessing an internal diameter which substantially corresponds to the diameter of said rotor means, said ring members partially limiting liquid-throughpassage means situated externally of said rotor means.
  • each extended member is defined by a ledge means.
  • a thin film apparatus as defined in claim 1 further including at least one spiral means for interconnecting both of said ring members.
  • each ring member is provided at its periphery with at least one cutout portion extending over the entire width of said ring member.
  • a thin film apparatus as defined in claim 1 further including a rotor provided with rotor vanes arranged in said treatment compartment, said rotor blades of said rotor means of said separation compartment being separate from said rotor vanes of said rotor of said treatment compartment.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
US44197A 1969-06-11 1970-06-08 Thin film apparatus Expired - Lifetime US3678983A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH888869A CH509558A (de) 1969-06-11 1969-06-11 Flüssigkeitsabscheider für Dünnschichtapparate

Publications (1)

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US3678983A true US3678983A (en) 1972-07-25

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US44197A Expired - Lifetime US3678983A (en) 1969-06-11 1970-06-08 Thin film apparatus

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US (1) US3678983A (de)
JP (1) JPS497318B1 (de)
CH (1) CH509558A (de)
FR (1) FR2045986A1 (de)
GB (1) GB1307416A (de)
SE (1) SE358091B (de)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3880668A (en) * 1972-04-05 1975-04-29 Western Consumers Ind Inc Apparatus for producing molasses food product
US3962028A (en) * 1974-09-09 1976-06-08 The De Laval Separator Company Swept surface evaporator
FR2463157A1 (fr) * 1978-03-13 1981-02-20 Owens Illinois Inc Procede de fabrication d'un terephtalate de polyethylene ameliore et stable
US4554055A (en) * 1983-03-07 1985-11-19 Phillips Petroleum Company Solvent recovery
US4965370A (en) * 1989-08-21 1990-10-23 Phillips Friedman Company N-methyl-2-pyrrolidone purification
US4981554A (en) * 1986-11-04 1991-01-01 Montedipe S.P.A. Thin-layer evaporator for high-viscosity, fluids
US5425849A (en) * 1991-04-11 1995-06-20 Feres; Vaclav Film-type evaporator
US5648032A (en) * 1995-08-01 1997-07-15 Eastman Chemical Company Process for producing polyester articles having low acetaldehyde content
US6512147B2 (en) 1997-10-28 2003-01-28 Ube Industries, Ltd. Apparatus and process for generating mixed multi-component vapor
US6627047B1 (en) * 1999-04-23 2003-09-30 Nippon Shokubai Co., Ltd. Method for preventing polymerization in thin-film type evaporating device
CN106669209A (zh) * 2016-12-30 2017-05-17 天津横天生物科技有限公司 一种刮板式薄膜浓缩器
CN113350897A (zh) * 2021-05-27 2021-09-07 李周滔 一种u形连体压力容器

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4313784A (en) * 1977-06-17 1982-02-02 International Refining Equipment Climbing film heat exchange apparatus
JP2016209779A (ja) * 2015-04-28 2016-12-15 関西化学機械製作株式会社 蒸発システム
CN109386994A (zh) * 2017-08-03 2019-02-26 沈阳天洁环保新能源有限公司 高效旋管式换热蒸发器及换热方法
CN111701262A (zh) * 2020-06-22 2020-09-25 天津科技大学 高效刮板薄膜蒸发装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1403804A (en) * 1916-10-30 1922-01-17 Merrell Soule Co Condensing apparatus
US2020211A (en) * 1934-10-29 1935-11-05 James P Quam Loud speaker
US2993842A (en) * 1959-05-07 1961-07-25 Arthur F Smith Fractionating processes and apparatus for carrying out the same
US3009514A (en) * 1957-12-30 1961-11-21 Gen Foods Corp Concentration process for aqueous gelatin solutions
US3234993A (en) * 1961-10-05 1966-02-15 Chemetron Corp Entrainment separator for wiped thin film processor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1403804A (en) * 1916-10-30 1922-01-17 Merrell Soule Co Condensing apparatus
US2020211A (en) * 1934-10-29 1935-11-05 James P Quam Loud speaker
US3009514A (en) * 1957-12-30 1961-11-21 Gen Foods Corp Concentration process for aqueous gelatin solutions
US2993842A (en) * 1959-05-07 1961-07-25 Arthur F Smith Fractionating processes and apparatus for carrying out the same
US3234993A (en) * 1961-10-05 1966-02-15 Chemetron Corp Entrainment separator for wiped thin film processor

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3880668A (en) * 1972-04-05 1975-04-29 Western Consumers Ind Inc Apparatus for producing molasses food product
US3962028A (en) * 1974-09-09 1976-06-08 The De Laval Separator Company Swept surface evaporator
FR2463157A1 (fr) * 1978-03-13 1981-02-20 Owens Illinois Inc Procede de fabrication d'un terephtalate de polyethylene ameliore et stable
US4554055A (en) * 1983-03-07 1985-11-19 Phillips Petroleum Company Solvent recovery
US4981554A (en) * 1986-11-04 1991-01-01 Montedipe S.P.A. Thin-layer evaporator for high-viscosity, fluids
US4965370A (en) * 1989-08-21 1990-10-23 Phillips Friedman Company N-methyl-2-pyrrolidone purification
US5425849A (en) * 1991-04-11 1995-06-20 Feres; Vaclav Film-type evaporator
US5648032A (en) * 1995-08-01 1997-07-15 Eastman Chemical Company Process for producing polyester articles having low acetaldehyde content
US6512147B2 (en) 1997-10-28 2003-01-28 Ube Industries, Ltd. Apparatus and process for generating mixed multi-component vapor
US6627047B1 (en) * 1999-04-23 2003-09-30 Nippon Shokubai Co., Ltd. Method for preventing polymerization in thin-film type evaporating device
MY120606A (en) * 1999-04-23 2005-11-30 Nippon Catalytic Chem Ind Method for preventing polymerization in thin-film type evaporating device
CN106669209A (zh) * 2016-12-30 2017-05-17 天津横天生物科技有限公司 一种刮板式薄膜浓缩器
CN113350897A (zh) * 2021-05-27 2021-09-07 李周滔 一种u形连体压力容器
CN113350897B (zh) * 2021-05-27 2022-07-12 烟台兴隆压力容器制造有限公司 一种u形连体压力容器

Also Published As

Publication number Publication date
DE2027357B2 (de) 1976-09-30
FR2045986A1 (de) 1971-03-05
JPS497318B1 (de) 1974-02-19
DE2027357A1 (de) 1970-12-23
SE358091B (de) 1973-07-23
CH509558A (de) 1971-06-30
GB1307416A (en) 1973-02-21

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