CA1037228A - Gaseous reaction apparatus and processes - Google Patents
Gaseous reaction apparatus and processesInfo
- Publication number
- CA1037228A CA1037228A CA215,956A CA215956A CA1037228A CA 1037228 A CA1037228 A CA 1037228A CA 215956 A CA215956 A CA 215956A CA 1037228 A CA1037228 A CA 1037228A
- Authority
- CA
- Canada
- Prior art keywords
- gas
- vessel
- pulp
- inlet
- conduit
- 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
Links
Classifications
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/18—Stationary reactors having moving elements inside
- B01J19/1868—Stationary reactors having moving elements inside resulting in a loop-type movement
- B01J19/1881—Stationary reactors having moving elements inside resulting in a loop-type movement externally, i.e. the mixture leaving the vessel and subsequently re-entering it
Abstract
ABSTRACT OF THE DISCLOSURE
Gaseous reaction apparatus and processes wherein a portion of the supplied gas is discharged from the re-action vessel at a location below the upper level of a therein contained columnar mass of material and such dis-charged portion of the gas, with or without cooling, is recirculated back into the upper inlet end of the vessel, thereby controlling the temperature in the vessel by re-moving or redistributing heat therein. Such apparatus and processes are particularly useful in the gas phase treatment of fiberous material such as the bleaching or delignification of lignin-containing cellulose pulp.
Gaseous reaction apparatus and processes wherein a portion of the supplied gas is discharged from the re-action vessel at a location below the upper level of a therein contained columnar mass of material and such dis-charged portion of the gas, with or without cooling, is recirculated back into the upper inlet end of the vessel, thereby controlling the temperature in the vessel by re-moving or redistributing heat therein. Such apparatus and processes are particularly useful in the gas phase treatment of fiberous material such as the bleaching or delignification of lignin-containing cellulose pulp.
Description
: ~03722B
The present invention relates to the yaseous re-action of material and more specifically to apparatus and processes particularly suited for the gas phase treatment of fiberous material such as, by way of specific example, the bleaching or delignification of lignin-containing ` cellulose pulp.
.. Conventi:onal apparatus and processes for the gaseous ~: reaction of fiberous material, such as the treatment of ............ cellulose pulp with oxygen, generally react the material 10 or pulp in a closed vessel and pre-heat the pulp, prior . - to its supply into such vessel, to a temperature sufficient-ly high to initiate the reaction process. The heat of . reaction of such processes is sometimes of such great magnitude as to cause undesirably great temperature rise : 15 in the closed vessel; however, the temperature of the pulp must, even after such temperature rise, be main-tained sufficiently low to a.void the undesirable degreda-: tion of the pulp which inherently results from too great heating. Such conventional apparatus and processes general-. 20 ly do not include any provision for removal or redistribution of heat in the closed vessel and attempt to control the temperature in the vessel only by control of the tempera',ure to which the pulp is pre-heated prior to its supply there-into. Hence, in such apparatus and processes, the temperature of the pulp in the inlet end of the vessel sometimes . necessarily must be so low as to require an undesirably - long retention time.in the vessel for completion of the reaction.
An object of the present invention is to provide new and improved apparatus and processes particularly adapt-.. ed for permitting control of the temperature in a reaction . -2- .
" .
7512 I~S(PA) vessel employed in a yaseous reaction process.
Another object of the invention is to provide new and improved apparatus and processes of the type set forth particularly adapted for permitting redistribution of the heat in the reaction vessel.
Another object is to provide new and improved ap- ;
paratus and processes of the type set forth particularly ` adapted for permitting the temperature in the vessel to be maintained at a predetermined maximum level.
10Another object is to provide new and improved ap paratus and processes of the type set forth particularly adapted for removal of heat from the reaction vessel.
Another object is to provide new and improved ap-paratus and processes of the type set forth particularly adapted for permitting the material to be rapidly pre-; heated in the vessel to a temperature desirable for the ~ reaction process. ;
- Other objects and advantages of the invention will be apparent from the fol]owing description taken in connection with the accompanying drawings wherein, as will be understood, the preferred forms of the invention have ~een given by way of illustration only.
In accordance with the invention, apparatus for the gaseous reaction of material may comprise a vessel, material supply means including material inlet means at one end of said vessel for supplying material thereinto, gas supply means including gas inlet means at said one end of said vessel for supplying reactant gas thereinto and to material therein, material discharge means in-cluding material outlet means at the other end of said .
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1037~28 vessel for discharging material therefrom, said vessel ;; being provided with unrestricted gas discharge opening means for discharging gas from a gas-material mixture in said vessel separately from the material in such mixture, said gas discharge opening means being substantially spaced longitudinally of said vessel from said material and gas inlet means and also spaced longitudinally of ` said vessel from said material outle`t means, and gas re-`~ eirculation conduit means communicating said gas discharge opening means with said one end of said vessel for re-`~ eireulating gas discharged through said gas discharge opening means back into said one end of said vessel.
Also, in accordance with the invention, a process for the gaseous reaction of material may comprise the . .
steps of supplying the material into one end of a re-action vessel, supplying gas into said one end of said reaction vessel, retaining the supplied material in said reaction vessel for a time period whereby a portion of the supplied gas reacts with the material and then dis-eharging the material from the vessel, discharging another . .
porti.on of the supplied gas from the vessel separately from the discharged material and at a location substantial-ly spaced from said one end of the vessel, and recirculat-ing such discharged portion of the gas back into said one end of the vessel.
`Referring to the drawings:
Fig. 1 is a view schematically illustrating one apparatus constructed in accordance with the present ; invention;
Fig. 2 is a view schematically illustrating a ~~
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`"~ second apparatus constructed in accordance with the invention' and t Fig- 3 is a view schematically illustrating a < thlrd apparatus constructed in accordance with the invention.
Referring more particularly to the drawings, where-in similar reference characters designate corresponding parts throughout the several views, the embodiment of 'i the apparatus shown in Fig. 1 comprises an elongated, - generally vertical or upright, annular reaction vessel 10.
The reaction vessel 10 includes an upper portion 12 -peripherally bounded by a generally vertical annular wall ~- -14, and a therebelow adjoining lower portion 16 peripherally enclosed within a gener~lly vertical annular wall 18. The upper portion 12 of the vessel 10 is formed of horizontal :: .: : .
; cross-section or cross-sectional area substantially less ,~ than that of the communicating lower portion 16; and the annular wall 18 is upwardly extended to project circumfer-' entially around the lower end of the annular wall 14 .: .
radially spaced therefrom by a relatively large cross-section annular gas receiving chamber 20 which extends peripherally around the lower end of the vessel upper ' portion 12 and throughout its length is closed by the - -~; wall 14 from direct connection thereto. The annular , ~
lower end 22 of the gas receiving chamber 20 surrounds the lower end of the vessel upper portion 12 to be sub-. ~
' stantially spaced from the vessel upper end, and is entirely :''`'.
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open to serve as an unrestricted, large annular opening through which, during operation of the apparatus, gas is continuously discharged. The upper end of the chamber 20 is closed by an annular closure wall 24, however, below the closure wall 24, a gas discharge outlet 26 is con-nected to the chamber 20 for discharging gas from the latter. The chamber 20, chambèr lower end 22 and gas outlet 26 are free from screens and similar filtering media such as might restrict the flow of gas therethrough;
and the screen plugging problems and screen cleaning difficulties, inherent in the provision of a screen at their locations, are resultantly avoided.
` The upper end of the vessel upper portion 12 (that is, the upper inlet end of the vessel i0) is provided with at least one gas inlet 28 which communicates such upper portion 12 with a gas supply conduit 30, in turn, com-municating with a source (not shown) of ~he gas or gaseous ..
reagent to be employed during the operation of the apparatus.
The upper end of the vessel upper portion 12 is further provided with a material inlet or inlet conduit 32 which ` is connected to such upper end generally centrally of the vessel 10. The inlet conduit 32 contains a feed screw 34, mounted on a supporting shaft 36 rotata~ly driven by a driving motor (not shown), which is adapted for down-wardly feeding the material into the vessel upper portion 12. The inlet conduit 32 is connected to a supply conduit ` 38 including a portion tapering or progressively narrowing .
` in cross-section in the direction of the passage of material to the vessel 10 therethrough. A rotatably driven shaft ~0 is coaxially disposed in the supply conduit 38 and in :
' ' the tapering cross-section portion thereof carries a feed-and-compaction screw 42. Hence, during operation of the ~ .
apparatus, the driven rotation of the feed-and-compaction `
screw 42 in the tapering portion of the conduit 38 causes . compaction of the material in the supply conduit 38 to . prevent the flow of gases therethrough, while the screws 34, 42 feed the material into the upper end of the vessel :
: upper portion 12.
The upper end of the vessel upper portion 12 contains means particularly adapted for disintegrating, breaking-up and fluffing the compacted material supplied through the inlet conduit 32, such means also spreading -. the disintegrated, broken-up and fluffed material across the cross-section of the vessel upper portion 12. As illus-; trated, such means comprise an inner annulus or ring 44 of .: arcuately spaced apart rotary pIns connected to the shaft 36 for driven rotation therewith, and a coaxial, radially spaced, outer annulus or ring 46 of arcuately spaced apart stationary pins. During operation of the apparatus, the . 20 annulus 44 of the rotary pins is continuously rotatably driven .~ relative to the annulus 46 of stationary pins; and material ~,.
supplied through the inlet conduit 32 is disintegrated or fluffed by the relative rotation of the pins and thence . .
. discharged outwardly through the spaces between the ad-jacent ones of the pins to be resultantly spread in fluffed, disintegrated or broken-up condition across the cross-section of the vessel 10. It will be understood that this , .
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illustrated material disintegrating and spreading means, and also the beforedescribed material compacting and supplying means, are shown as beiny of described con-struction only for the purposes of illustration and could be of other construction suitable to perform their intended functions. The lower end of the vessel lower portion 16 (that is; the lower discharge end of the vessel) is pro-vided with a reacted material outlet or outlet conduit 48 ; and contains a bottom scraper 50 rotatably driven through a shaft 52 for discharging the material through such - outlet 48.
In accordance with the present invention, the apparatus further includes means for redistributing heat ~; in the react.ion vessel 10 during the reaction process to ~ 15 control the temperature therein. ~lore specifically, as ;; shown in Fig. 1, a recirculation conduit 54, external to the vessel 10, is connected at opposite ends to the gas outlet 26 and the gas inlet 28 for recirculating the gas discharged through the gas outlet 26 back through t~e gas inlet 28 into the upper end of the vessel. The xe-circulation conduit 54, moreover, is provided with a -~ convenlional centrifugal hlower 56 adapted for blo~ing ;-~ the recirculated gas through the recirculation conduit .i .
- 54 to the ~as inlet 28; and, as illustrated, the gas ~-supply conduit 30 is connected to the gas inlet 28 through ~; the recirculation conduit 54 whereby the recirculated gas and t}le g-as supplied by t~le conduit 30 are supplied interTnixed through the inlet 28.
A description of the operation of the before-.
described apparatus in the oxygen delignification of ., '~
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7512 IMP~) cellulose pulp hereinafter follows, it being estimated`
that the heat of such reaction is sufficient to raise the temperature of pulp in the vessel 10 about ei.ghty degrees Fahrenheit and it beiny understood that the maximum . 5 ternperature in the vessel 10 during such reaction must be ;~ maintained below about two-hundred fifty degrees Fahrenheit to prevent degredation of the pulp.
Throughout such operationr the shafts 36, 40, 52, are continuously rotatably driven to provide continuous rotation of the screws 34, 42, the annulus 44 of rotary pins and the bottom scraper 50. Pulp being reacted is retained in the vessel 10 for the period of time suitable : or desirable for the reaction in a porous, gas permeable pile or plug of fluffed pulp, which pile has its upper end ,~ 15 generally as indicated by the reference numeral 58 and spaced below the upper end of the vessel upper portion 12 by a gas space 60. The pulp moves progressively downwardly - in such porous plug form as reacted pulp is discharged ,~: from the bottom of the plug through the outlet 48. The pulp plug, thus maintained in the vessel 1.0, adjacent its upper end extends the full cross-section of the vessel :
upper portion 12 and expands in cross-section in the vessel lower portion 16 to the full width of the latter, thereby causing the pcrous pulp plug to have a large `~ 25 annular interface lOQ with the gas receiving chamber 20. .
:
Pulp to be reacted is continuously supplied to the feed-and-compaction screw 42 which compacts the pulp in the taperin~ portion of the supply conduit 38 and thereby forms a non-porous plug of the pulp upstream of the vessel 10 to prevent flow of gas to the vessel 10 throu~h the condui.t 38 and also preven. loss of gas 1037ZZ~
from the vessel 10 through the conduit 38. The feed screw 34 continuously receives this plug of pulp from - the conduit 38 and feeds the pulp downwardly to the therebelow annuli 44, 46 of relatively rotating pins.
Such pins, due to their relative rotation, disintegrate and fluff the pulp to a condition suitable for the reaction and the formation in the vessel 10 of the be-foredescribed porous, gas permeable pulp plug. The ~-:
annuli 44, 46 of pins, furthermore, discharge the pulp in a radially outward flow between adjacent ones of the ' pins whereby the pulp showers downwardly through the space 60 onto the upper end 58 of the therebelow pulp plug.
The temperature of this supplied pulp may be, for example, around one-hundred seventy degrees Fahrenheit.
~;i Simultaneously, reaction gas or oxygen is con-, tinuously supplied at a controlled rate from the gas supply conduit 30 through the gas inlet 28 into the gas ,, space 60 and to the pulp showering downwardly therethrough.
~ Hence, the pulp during its downward showering is exposed 'l 20 to the introduced reaction gas and a large portion of the , reaction gas is absorbed into the pulp at this time. The :. ~
unabsorbed gas continues downwardly through the porous ~-pulp plug at a velocity which is substantially greater ~
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~:, than that of the downward movement of the pulp through : '"
; the plug, an additional volume of the reaction gas being - absorbed into the pulp during such downward flow, and the remaining unabsorbed gas at the level of the inter-face 100 passes upwardly through the gas discharge opening 22 into the gas chamber 20 and thence is recirculated through the gas recirculation conduit 54 by the blower - 56 into the upper end of the vessel upper portion 12.
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` 1037228 The recirculated gas is, as will be noted, supplied into the gas space 60 through the gas inlet 28 intermixed with gas from the gas supply conduit 30. The major portion of the heat contained in the recirculated gas is in the form of water vapor originating from the lower end of the upper vessel portion 12 where, due to heat of reaction, evapora-tion of water from the hot pulp occurs. The recirculated gas entering the gas space 60 has a higher temperature than the entering pulp and, due to the high turbulence in .,;~.
`.~ 10 the gas space 60 and the large exposed surface area of the ~` pulp showering downwardly therethrough~ heat transfer from . ~ .
: the recirculated gas to such pulp by condensation of the . water vapor contained in the recirculated gas occurs almost . instantaneously whereby substantially equalized temperature ; : of the recirculated gas and the fluffed pulp is attained ~:
:' prior to the deposit of the pulp on the upper level of the i.~
~:. pulp bed 58. The amount of this heat transfer from the ., . recirculated gas to the pulp, is, of course, dependent .'.~ upon the volume of gas recirculated. However, it has been ;` 20 calculated for a case where the temperature rise within , .
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the pulp bed 58 due to heat of reaction would be eighty degrees Fahrenheit without gas recirculation, that re-circulation of three-tenths to eight-tenths of a pound of oxygen per pound of pulp would limit the temperature rise within the pulp bed 58 to forty to sixty degrees Fahrenheit, while elevating the temperature of ~he entering pulp in -the gas space 60 by twenty to forty degrees Fahrenheit (for example, from one-hundred seventy degrees Fahrenheight to a . ~ range of one-hundred ninety to two-hundred ten degrees `: 30 Fahrenheit) - that is, to a temperature level that will :
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immediately begin a fast process reaction. Within the pulp bed 58, the downward flow of gas acts to limit the temperature rise by evaporating water and absorbing heat generated by heat reaction from the hot pulp, and thereby prevents overheating and degradation of the pulp.
Fig. 2, wherein parts similar to those before-described are designated by the corresponding reference numerals followed by the suffix "a" illustrates an embodi-ment of the apparatus particularly adapted for employment in applications where cooling of the recirculated gas is necessary or desirable. In the Fig. 2 embodiment, a cooler, designated generally as 62, is interposed in the gas re-circulation conduit 54a for cooling the recirculated gas during its flow through such conduit 54a. The cooler 62 may be of any suitable conventional construction such as, for example, an indirect type heat exchanger or a direct type spray condenser and enables the temperature --~ .
of the recirculated gas to be sufficiently lowered as to provide control of the temperature in the vessel lOa, it being believed that such cooling of the recirculated gas is particularly beneficial in applications such as, for example, the gas phase chlorination of cellulose pulp.
Aside from the cooler 62, the only differences between the apparatus of Fig. 2 and Fig. 1 are that the former locates the blower 56a adjacent to the gas inlet 28a and connects the gas supply conduit 30a to the recirculation conduit 54a upstream of the blower 56a. The operation of the apparatus shown in Fig. 2 is believed to be apparent in view of the beforegiven description of the operation of the apparatus of Fig. 1.
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, Fig. 3, wherein parts similar to those of the : beforedescribed apparatus of Figs. 1 and 2 are designated by the corresponding reference numerals followed by the suffix "b", illustrates an embodiment of the apparatus particularly suited for employment in instances in which the supplied reactant gas must be diluted by an inert ` carrier gas such as nitrogen, air or steam. As shown in `; Fig. 3, the fluffing~-of the pulp occurs in a fluffer 64 ;
external to the vessel lOb. The fluffer 64 may include coasial annuli of rotating and stationary pins and is connected to the material inlet 68 at the upper end of the vessel upper portion 12b by a material supply . . .
~,~ conduit 66 while also connected to such upper end through a gas discharge conduit 70 arranged to discharge gas from ~r ,~ the vessel upper end, whereby such discharged gas blows ., .
` ; the fluffed or disintegrated pulp from the fluffer 64 ;
through the conduit 66 into the upper end of the vessel , upper portion 12b. The discharge outlet 48b at the lower ~ . .
end of the vessel lOb is provided with a rotatably driven discharge screw 72: and the vessel lOb beneath the vessel portion 16b includes a discharge chamber or section 74 separated from the lower end of the vessel portion 16b by a rotatably driven discharge platform 76 which controls ; the discharge of pulp from the bottom of the pulp plug to the discharge chamber 74 around the platform 76. The gas recirculation conduit 54b, as shown, may contain a . . , . :
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,'.'', , ',. . ~, 7512 I~(P~) :;; i '.`: 103qZZ~ ' cooler 62b and communicates with the gas inlet 28b through a conventional gas generating system designated generally as 78 and, per se, of any suitable conventional construction.
In the operation of the apparatus of Fig. 3, the gasldischarged from the gas chamber 20b to the gas recir~
;`' culation conduit 54b is primarily inert carrier gas t~ S
~h~^ougll preferably having therewith a residue of the re~
actant gas to prevent the reaction from being undesirably slow adjacent the lower end of the vessel upper `portion 12b, and is recirculated to the gas generation system 76 ~`
;~ which adds additional reactant gas to the carrier gas ~ `
prior to resupply through the gas inlet 28b into the gas ~` space 60b. The Fig. 3 embodiment is believed to be ; particularly useful in the treatment of fluffed pulp in ;
lS gas phase with chlorine monoxide and chlorine dioxide, but of course is not limited merely to these applications. ~;
It will be understood that, although the Fig. 3 embodiment ` has been shown and described as including a fluffer 64 external to the vessel lOb, it could alternatively include a fluffer within such vessel lOb and, for example, of the relatively rotating pin construction shown in the upper ends of the vessels 10, lOa of the embodiments of Figs. 1 and 2. Furthermore, such fluffers shown in the embodiments of Figs. 1 and 2 could, if desired, be replaced by an external fluffer such as that shown as 64 in the embodiment of Fig. 3.
: From the preceding description it will be seen that the invention provides new and improved apparatus and :::
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processes for accomplishing all of the beforestated objects and advantages. It will be understood, however, that although only three embodiments of the invention have been illustrated and hereinbefore described, the invention is not limited merely to these three embodiments, Co~ /a fes ~ but rather ~ !te~F'~n~ other e~odiments and variations ; within the scope of the following claims.
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The present invention relates to the yaseous re-action of material and more specifically to apparatus and processes particularly suited for the gas phase treatment of fiberous material such as, by way of specific example, the bleaching or delignification of lignin-containing ` cellulose pulp.
.. Conventi:onal apparatus and processes for the gaseous ~: reaction of fiberous material, such as the treatment of ............ cellulose pulp with oxygen, generally react the material 10 or pulp in a closed vessel and pre-heat the pulp, prior . - to its supply into such vessel, to a temperature sufficient-ly high to initiate the reaction process. The heat of . reaction of such processes is sometimes of such great magnitude as to cause undesirably great temperature rise : 15 in the closed vessel; however, the temperature of the pulp must, even after such temperature rise, be main-tained sufficiently low to a.void the undesirable degreda-: tion of the pulp which inherently results from too great heating. Such conventional apparatus and processes general-. 20 ly do not include any provision for removal or redistribution of heat in the closed vessel and attempt to control the temperature in the vessel only by control of the tempera',ure to which the pulp is pre-heated prior to its supply there-into. Hence, in such apparatus and processes, the temperature of the pulp in the inlet end of the vessel sometimes . necessarily must be so low as to require an undesirably - long retention time.in the vessel for completion of the reaction.
An object of the present invention is to provide new and improved apparatus and processes particularly adapt-.. ed for permitting control of the temperature in a reaction . -2- .
" .
7512 I~S(PA) vessel employed in a yaseous reaction process.
Another object of the invention is to provide new and improved apparatus and processes of the type set forth particularly adapted for permitting redistribution of the heat in the reaction vessel.
Another object is to provide new and improved ap- ;
paratus and processes of the type set forth particularly ` adapted for permitting the temperature in the vessel to be maintained at a predetermined maximum level.
10Another object is to provide new and improved ap paratus and processes of the type set forth particularly adapted for removal of heat from the reaction vessel.
Another object is to provide new and improved ap-paratus and processes of the type set forth particularly adapted for permitting the material to be rapidly pre-; heated in the vessel to a temperature desirable for the ~ reaction process. ;
- Other objects and advantages of the invention will be apparent from the fol]owing description taken in connection with the accompanying drawings wherein, as will be understood, the preferred forms of the invention have ~een given by way of illustration only.
In accordance with the invention, apparatus for the gaseous reaction of material may comprise a vessel, material supply means including material inlet means at one end of said vessel for supplying material thereinto, gas supply means including gas inlet means at said one end of said vessel for supplying reactant gas thereinto and to material therein, material discharge means in-cluding material outlet means at the other end of said .
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1037~28 vessel for discharging material therefrom, said vessel ;; being provided with unrestricted gas discharge opening means for discharging gas from a gas-material mixture in said vessel separately from the material in such mixture, said gas discharge opening means being substantially spaced longitudinally of said vessel from said material and gas inlet means and also spaced longitudinally of ` said vessel from said material outle`t means, and gas re-`~ eirculation conduit means communicating said gas discharge opening means with said one end of said vessel for re-`~ eireulating gas discharged through said gas discharge opening means back into said one end of said vessel.
Also, in accordance with the invention, a process for the gaseous reaction of material may comprise the . .
steps of supplying the material into one end of a re-action vessel, supplying gas into said one end of said reaction vessel, retaining the supplied material in said reaction vessel for a time period whereby a portion of the supplied gas reacts with the material and then dis-eharging the material from the vessel, discharging another . .
porti.on of the supplied gas from the vessel separately from the discharged material and at a location substantial-ly spaced from said one end of the vessel, and recirculat-ing such discharged portion of the gas back into said one end of the vessel.
`Referring to the drawings:
Fig. 1 is a view schematically illustrating one apparatus constructed in accordance with the present ; invention;
Fig. 2 is a view schematically illustrating a ~~
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`"~ second apparatus constructed in accordance with the invention' and t Fig- 3 is a view schematically illustrating a < thlrd apparatus constructed in accordance with the invention.
Referring more particularly to the drawings, where-in similar reference characters designate corresponding parts throughout the several views, the embodiment of 'i the apparatus shown in Fig. 1 comprises an elongated, - generally vertical or upright, annular reaction vessel 10.
The reaction vessel 10 includes an upper portion 12 -peripherally bounded by a generally vertical annular wall ~- -14, and a therebelow adjoining lower portion 16 peripherally enclosed within a gener~lly vertical annular wall 18. The upper portion 12 of the vessel 10 is formed of horizontal :: .: : .
; cross-section or cross-sectional area substantially less ,~ than that of the communicating lower portion 16; and the annular wall 18 is upwardly extended to project circumfer-' entially around the lower end of the annular wall 14 .: .
radially spaced therefrom by a relatively large cross-section annular gas receiving chamber 20 which extends peripherally around the lower end of the vessel upper ' portion 12 and throughout its length is closed by the - -~; wall 14 from direct connection thereto. The annular , ~
lower end 22 of the gas receiving chamber 20 surrounds the lower end of the vessel upper portion 12 to be sub-. ~
' stantially spaced from the vessel upper end, and is entirely :''`'.
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open to serve as an unrestricted, large annular opening through which, during operation of the apparatus, gas is continuously discharged. The upper end of the chamber 20 is closed by an annular closure wall 24, however, below the closure wall 24, a gas discharge outlet 26 is con-nected to the chamber 20 for discharging gas from the latter. The chamber 20, chambèr lower end 22 and gas outlet 26 are free from screens and similar filtering media such as might restrict the flow of gas therethrough;
and the screen plugging problems and screen cleaning difficulties, inherent in the provision of a screen at their locations, are resultantly avoided.
` The upper end of the vessel upper portion 12 (that is, the upper inlet end of the vessel i0) is provided with at least one gas inlet 28 which communicates such upper portion 12 with a gas supply conduit 30, in turn, com-municating with a source (not shown) of ~he gas or gaseous ..
reagent to be employed during the operation of the apparatus.
The upper end of the vessel upper portion 12 is further provided with a material inlet or inlet conduit 32 which ` is connected to such upper end generally centrally of the vessel 10. The inlet conduit 32 contains a feed screw 34, mounted on a supporting shaft 36 rotata~ly driven by a driving motor (not shown), which is adapted for down-wardly feeding the material into the vessel upper portion 12. The inlet conduit 32 is connected to a supply conduit ` 38 including a portion tapering or progressively narrowing .
` in cross-section in the direction of the passage of material to the vessel 10 therethrough. A rotatably driven shaft ~0 is coaxially disposed in the supply conduit 38 and in :
' ' the tapering cross-section portion thereof carries a feed-and-compaction screw 42. Hence, during operation of the ~ .
apparatus, the driven rotation of the feed-and-compaction `
screw 42 in the tapering portion of the conduit 38 causes . compaction of the material in the supply conduit 38 to . prevent the flow of gases therethrough, while the screws 34, 42 feed the material into the upper end of the vessel :
: upper portion 12.
The upper end of the vessel upper portion 12 contains means particularly adapted for disintegrating, breaking-up and fluffing the compacted material supplied through the inlet conduit 32, such means also spreading -. the disintegrated, broken-up and fluffed material across the cross-section of the vessel upper portion 12. As illus-; trated, such means comprise an inner annulus or ring 44 of .: arcuately spaced apart rotary pIns connected to the shaft 36 for driven rotation therewith, and a coaxial, radially spaced, outer annulus or ring 46 of arcuately spaced apart stationary pins. During operation of the apparatus, the . 20 annulus 44 of the rotary pins is continuously rotatably driven .~ relative to the annulus 46 of stationary pins; and material ~,.
supplied through the inlet conduit 32 is disintegrated or fluffed by the relative rotation of the pins and thence . .
. discharged outwardly through the spaces between the ad-jacent ones of the pins to be resultantly spread in fluffed, disintegrated or broken-up condition across the cross-section of the vessel 10. It will be understood that this , .
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` 7512 IM(I~
illustrated material disintegrating and spreading means, and also the beforedescribed material compacting and supplying means, are shown as beiny of described con-struction only for the purposes of illustration and could be of other construction suitable to perform their intended functions. The lower end of the vessel lower portion 16 (that is; the lower discharge end of the vessel) is pro-vided with a reacted material outlet or outlet conduit 48 ; and contains a bottom scraper 50 rotatably driven through a shaft 52 for discharging the material through such - outlet 48.
In accordance with the present invention, the apparatus further includes means for redistributing heat ~; in the react.ion vessel 10 during the reaction process to ~ 15 control the temperature therein. ~lore specifically, as ;; shown in Fig. 1, a recirculation conduit 54, external to the vessel 10, is connected at opposite ends to the gas outlet 26 and the gas inlet 28 for recirculating the gas discharged through the gas outlet 26 back through t~e gas inlet 28 into the upper end of the vessel. The xe-circulation conduit 54, moreover, is provided with a -~ convenlional centrifugal hlower 56 adapted for blo~ing ;-~ the recirculated gas through the recirculation conduit .i .
- 54 to the ~as inlet 28; and, as illustrated, the gas ~-supply conduit 30 is connected to the gas inlet 28 through ~; the recirculation conduit 54 whereby the recirculated gas and t}le g-as supplied by t~le conduit 30 are supplied interTnixed through the inlet 28.
A description of the operation of the before-.
described apparatus in the oxygen delignification of ., '~
-8- ~
.,' , ~
7512 IMP~) cellulose pulp hereinafter follows, it being estimated`
that the heat of such reaction is sufficient to raise the temperature of pulp in the vessel 10 about ei.ghty degrees Fahrenheit and it beiny understood that the maximum . 5 ternperature in the vessel 10 during such reaction must be ;~ maintained below about two-hundred fifty degrees Fahrenheit to prevent degredation of the pulp.
Throughout such operationr the shafts 36, 40, 52, are continuously rotatably driven to provide continuous rotation of the screws 34, 42, the annulus 44 of rotary pins and the bottom scraper 50. Pulp being reacted is retained in the vessel 10 for the period of time suitable : or desirable for the reaction in a porous, gas permeable pile or plug of fluffed pulp, which pile has its upper end ,~ 15 generally as indicated by the reference numeral 58 and spaced below the upper end of the vessel upper portion 12 by a gas space 60. The pulp moves progressively downwardly - in such porous plug form as reacted pulp is discharged ,~: from the bottom of the plug through the outlet 48. The pulp plug, thus maintained in the vessel 1.0, adjacent its upper end extends the full cross-section of the vessel :
upper portion 12 and expands in cross-section in the vessel lower portion 16 to the full width of the latter, thereby causing the pcrous pulp plug to have a large `~ 25 annular interface lOQ with the gas receiving chamber 20. .
:
Pulp to be reacted is continuously supplied to the feed-and-compaction screw 42 which compacts the pulp in the taperin~ portion of the supply conduit 38 and thereby forms a non-porous plug of the pulp upstream of the vessel 10 to prevent flow of gas to the vessel 10 throu~h the condui.t 38 and also preven. loss of gas 1037ZZ~
from the vessel 10 through the conduit 38. The feed screw 34 continuously receives this plug of pulp from - the conduit 38 and feeds the pulp downwardly to the therebelow annuli 44, 46 of relatively rotating pins.
Such pins, due to their relative rotation, disintegrate and fluff the pulp to a condition suitable for the reaction and the formation in the vessel 10 of the be-foredescribed porous, gas permeable pulp plug. The ~-:
annuli 44, 46 of pins, furthermore, discharge the pulp in a radially outward flow between adjacent ones of the ' pins whereby the pulp showers downwardly through the space 60 onto the upper end 58 of the therebelow pulp plug.
The temperature of this supplied pulp may be, for example, around one-hundred seventy degrees Fahrenheit.
~;i Simultaneously, reaction gas or oxygen is con-, tinuously supplied at a controlled rate from the gas supply conduit 30 through the gas inlet 28 into the gas ,, space 60 and to the pulp showering downwardly therethrough.
~ Hence, the pulp during its downward showering is exposed 'l 20 to the introduced reaction gas and a large portion of the , reaction gas is absorbed into the pulp at this time. The :. ~
unabsorbed gas continues downwardly through the porous ~-pulp plug at a velocity which is substantially greater ~
.. ,, l . .
~:, than that of the downward movement of the pulp through : '"
; the plug, an additional volume of the reaction gas being - absorbed into the pulp during such downward flow, and the remaining unabsorbed gas at the level of the inter-face 100 passes upwardly through the gas discharge opening 22 into the gas chamber 20 and thence is recirculated through the gas recirculation conduit 54 by the blower - 56 into the upper end of the vessel upper portion 12.
' ' ' - 1 0 -.` :
:
` 1037228 The recirculated gas is, as will be noted, supplied into the gas space 60 through the gas inlet 28 intermixed with gas from the gas supply conduit 30. The major portion of the heat contained in the recirculated gas is in the form of water vapor originating from the lower end of the upper vessel portion 12 where, due to heat of reaction, evapora-tion of water from the hot pulp occurs. The recirculated gas entering the gas space 60 has a higher temperature than the entering pulp and, due to the high turbulence in .,;~.
`.~ 10 the gas space 60 and the large exposed surface area of the ~` pulp showering downwardly therethrough~ heat transfer from . ~ .
: the recirculated gas to such pulp by condensation of the . water vapor contained in the recirculated gas occurs almost . instantaneously whereby substantially equalized temperature ; : of the recirculated gas and the fluffed pulp is attained ~:
:' prior to the deposit of the pulp on the upper level of the i.~
~:. pulp bed 58. The amount of this heat transfer from the ., . recirculated gas to the pulp, is, of course, dependent .'.~ upon the volume of gas recirculated. However, it has been ;` 20 calculated for a case where the temperature rise within , .
.
the pulp bed 58 due to heat of reaction would be eighty degrees Fahrenheit without gas recirculation, that re-circulation of three-tenths to eight-tenths of a pound of oxygen per pound of pulp would limit the temperature rise within the pulp bed 58 to forty to sixty degrees Fahrenheit, while elevating the temperature of ~he entering pulp in -the gas space 60 by twenty to forty degrees Fahrenheit (for example, from one-hundred seventy degrees Fahrenheight to a . ~ range of one-hundred ninety to two-hundred ten degrees `: 30 Fahrenheit) - that is, to a temperature level that will :
'~'' ' : :`
`"` ~037221~
immediately begin a fast process reaction. Within the pulp bed 58, the downward flow of gas acts to limit the temperature rise by evaporating water and absorbing heat generated by heat reaction from the hot pulp, and thereby prevents overheating and degradation of the pulp.
Fig. 2, wherein parts similar to those before-described are designated by the corresponding reference numerals followed by the suffix "a" illustrates an embodi-ment of the apparatus particularly adapted for employment in applications where cooling of the recirculated gas is necessary or desirable. In the Fig. 2 embodiment, a cooler, designated generally as 62, is interposed in the gas re-circulation conduit 54a for cooling the recirculated gas during its flow through such conduit 54a. The cooler 62 may be of any suitable conventional construction such as, for example, an indirect type heat exchanger or a direct type spray condenser and enables the temperature --~ .
of the recirculated gas to be sufficiently lowered as to provide control of the temperature in the vessel lOa, it being believed that such cooling of the recirculated gas is particularly beneficial in applications such as, for example, the gas phase chlorination of cellulose pulp.
Aside from the cooler 62, the only differences between the apparatus of Fig. 2 and Fig. 1 are that the former locates the blower 56a adjacent to the gas inlet 28a and connects the gas supply conduit 30a to the recirculation conduit 54a upstream of the blower 56a. The operation of the apparatus shown in Fig. 2 is believed to be apparent in view of the beforegiven description of the operation of the apparatus of Fig. 1.
.,''''' .
:, ,.: .
1037~2~3 :
, Fig. 3, wherein parts similar to those of the : beforedescribed apparatus of Figs. 1 and 2 are designated by the corresponding reference numerals followed by the suffix "b", illustrates an embodiment of the apparatus particularly suited for employment in instances in which the supplied reactant gas must be diluted by an inert ` carrier gas such as nitrogen, air or steam. As shown in `; Fig. 3, the fluffing~-of the pulp occurs in a fluffer 64 ;
external to the vessel lOb. The fluffer 64 may include coasial annuli of rotating and stationary pins and is connected to the material inlet 68 at the upper end of the vessel upper portion 12b by a material supply . . .
~,~ conduit 66 while also connected to such upper end through a gas discharge conduit 70 arranged to discharge gas from ~r ,~ the vessel upper end, whereby such discharged gas blows ., .
` ; the fluffed or disintegrated pulp from the fluffer 64 ;
through the conduit 66 into the upper end of the vessel , upper portion 12b. The discharge outlet 48b at the lower ~ . .
end of the vessel lOb is provided with a rotatably driven discharge screw 72: and the vessel lOb beneath the vessel portion 16b includes a discharge chamber or section 74 separated from the lower end of the vessel portion 16b by a rotatably driven discharge platform 76 which controls ; the discharge of pulp from the bottom of the pulp plug to the discharge chamber 74 around the platform 76. The gas recirculation conduit 54b, as shown, may contain a . . , . :
,' ':
,'.'', , ',. . ~, 7512 I~(P~) :;; i '.`: 103qZZ~ ' cooler 62b and communicates with the gas inlet 28b through a conventional gas generating system designated generally as 78 and, per se, of any suitable conventional construction.
In the operation of the apparatus of Fig. 3, the gasldischarged from the gas chamber 20b to the gas recir~
;`' culation conduit 54b is primarily inert carrier gas t~ S
~h~^ougll preferably having therewith a residue of the re~
actant gas to prevent the reaction from being undesirably slow adjacent the lower end of the vessel upper `portion 12b, and is recirculated to the gas generation system 76 ~`
;~ which adds additional reactant gas to the carrier gas ~ `
prior to resupply through the gas inlet 28b into the gas ~` space 60b. The Fig. 3 embodiment is believed to be ; particularly useful in the treatment of fluffed pulp in ;
lS gas phase with chlorine monoxide and chlorine dioxide, but of course is not limited merely to these applications. ~;
It will be understood that, although the Fig. 3 embodiment ` has been shown and described as including a fluffer 64 external to the vessel lOb, it could alternatively include a fluffer within such vessel lOb and, for example, of the relatively rotating pin construction shown in the upper ends of the vessels 10, lOa of the embodiments of Figs. 1 and 2. Furthermore, such fluffers shown in the embodiments of Figs. 1 and 2 could, if desired, be replaced by an external fluffer such as that shown as 64 in the embodiment of Fig. 3.
: From the preceding description it will be seen that the invention provides new and improved apparatus and :::
: j -14- `
7512 I~l(PA) Y "
~037221~ ~
processes for accomplishing all of the beforestated objects and advantages. It will be understood, however, that although only three embodiments of the invention have been illustrated and hereinbefore described, the invention is not limited merely to these three embodiments, Co~ /a fes ~ but rather ~ !te~F'~n~ other e~odiments and variations ; within the scope of the following claims.
,, ' `:
' 10 .~ ' .
.
.
~':
, . . .
,, ~ .
.
': -.
: . .~ . .
.
`
Claims (4)
1. Apparatus for the gaseous reaction of material, com-prising a generally vertical vessel, material supply means con-nected to the upper end of said vessel for supplying material into such upper end, gas supply means connected to the upper end of said vessel for supplying gas into such upper end and to material therein, means for discharging material from the lower end of said vessel, said vessel including an upper portion and a therebelow adjoining lower portion of cross-section greater than said upper portion, the juncture of said vessel portions being substantially spaced intermediate the upper and lower ends of said vessel, the outer periphery of said vessel adjacent said juncture of said vessel portions being provided with gas dis-charge means open to said vessel for discharging gas therefrom, said gas discharge means including a gas receiving chamber extending along the outer periphery of said vessel and open to said vessel lower portion through an unrestricted opening to receive gas therefrom, said gas discharge means further including gas outlet means connected to said chamber for discharging gas from said chamber; said chamber, said unrestricted opening and said gas outlet means being free from screens and similar filter-ing media, gas recirculation conduit means connecting said gas outlet means with said upper end of said vessel for recirculating gas discharged from said vessel through said gas outlet means back into said upper end of said vessel, and blower means connect-ed to said gas recirculation conduit means for causing gas dis-charged by said gas outlet means to flow through said gas recircu-lation conduit means towards said upper end of said vessel.
2. Gaseous reaction apparatus according to claim 1, further comprising cooler means connected to said gas recirculation conduit means for cooling the recirculated gas during its flow through such conduit means.
3. Gaseous reaction apparatus according to claim 1, wherein said gas supply means comprises at least one gas inlet at the upper end of said vessel and a source of gas communicating with said gas inlet to supply gas therethrough, said gas recircu-lation conduit means being connected to said gas inlet to recirculate the discharged gas therethrough.
4. Gaseous reaction apparatus according to claim 1, wherein said material supply means comprises at least one material inlet at the upper end of said vessel, material supply conduit means communicating with said material inlet for supplying material therethrough, compacting means operatively communicat-ing with said material supply conduit means for compacting material upstream of said material inlet, and material disintegrat-ing means operatively communicating with said material compact-ing means downstream of said material compacting means for disintegrating the material compacted by said material compacting means.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/445,212 US3964962A (en) | 1974-02-25 | 1974-02-25 | Gaseous reaction apparatus and processes including a peripheral gas receiving chamber and a gas recirculation conduit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1037228A true CA1037228A (en) | 1978-08-29 |
Family
ID=23768019
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA215,956A Expired CA1037228A (en) | 1974-02-25 | 1974-12-13 | Gaseous reaction apparatus and processes |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US3964962A (en) |
| JP (1) | JPS5833012B2 (en) |
| BR (1) | BR7500335A (en) |
| CA (1) | CA1037228A (en) |
| DE (1) | DE2507414A1 (en) |
| FI (1) | FI64821C (en) |
| NO (1) | NO141921B (en) |
| SE (1) | SE426855C (en) |
Families Citing this family (34)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE391544C (en) * | 1974-12-10 | 1985-10-10 | Billeruds Ab | SET FOR FORCED HEART MATCHING WOOD TIP |
| NO137651C (en) * | 1975-10-31 | 1978-03-29 | Myrens Verksted As | PROCEDURE AND APPARATUS FOR CONTINUOUS TREATMENT OF FINDEL FIBER MATERIAL OR CELLULOSIZED MASS WITH GAS WITHOUT COVER. |
| FI67413C (en) * | 1977-04-27 | 1985-03-11 | Myrens Verksted As | FOERFARANDE FOER BEHANDLING AV FINFOERDELAD FIBERHALTIG ELLER CELLULOSAHALTIG MASS SAMT ANORDNING FOER UTFOERANDE AV FOERFARANDET |
| US4128454A (en) * | 1977-12-07 | 1978-12-05 | Ingersoll-Rand Co. | System and method for gas phase pulp bleaching |
| US4209359A (en) * | 1978-10-23 | 1980-06-24 | International Paper Company | Process for removing residual oxygen from oxygen-bleached pulp |
| US4384920A (en) * | 1981-04-06 | 1983-05-24 | The Black Clawson Company | Method and apparatus for oxygen delignification |
| CA1219733A (en) * | 1983-08-11 | 1987-03-31 | Ingersoll-Rand Company | Gaseous reaction apparatus and process |
| US4581104A (en) * | 1983-08-11 | 1986-04-08 | Ingersoll-Rand Company | Method of reducing the lignin in wood pulp with oxygen gas recirculation |
| JP2510636Y2 (en) * | 1986-05-15 | 1996-09-18 | オリンパス光学工業株式会社 | Surgical microscope |
| FI79361B (en) * | 1988-01-05 | 1989-08-31 | Ahlstroem Oy | FOERFARANDE OCH APPARATUR FOER UNDERLAETTANDE AV UTTOEMNING AV FALLROER ELLER LIKNANDE OCH BEHANDLING AV MASSA I SAGDA UTRYMME. |
| SE462567B (en) * | 1988-11-25 | 1990-07-16 | Sunds Defibrator Ind Ab | DEVICE FOR CONTINUOUS TREATMENT OF CELLULOSAMASSA WITH AN ACTIVATING CHEMICAL |
| US5211811A (en) * | 1989-02-15 | 1993-05-18 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification |
| US5409570A (en) * | 1989-02-15 | 1995-04-25 | Union Camp Patent Holding, Inc. | Process for ozone bleaching of oxygen delignified pulp while conveying the pulp through a reaction zone |
| US5472572A (en) * | 1990-10-26 | 1995-12-05 | Union Camp Patent Holding, Inc. | Reactor for bleaching high consistency pulp with ozone |
| US5188708A (en) * | 1989-02-15 | 1993-02-23 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification followed by ozone relignification |
| US5181989A (en) * | 1990-10-26 | 1993-01-26 | Union Camp Patent Holdings, Inc. | Reactor for bleaching high consistency pulp with ozone |
| AT395180B (en) * | 1989-08-16 | 1992-10-12 | Andritz Ag Maschf | METHOD FOR CRUSHING MATERIALS AND SYSTEM FOR IMPLEMENTING IT |
| US5441603A (en) * | 1990-05-17 | 1995-08-15 | Union Camp Patent Holding, Inc. | Method for chelation of pulp prior to ozone delignification |
| US5164043A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5164044A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5520783A (en) * | 1990-10-26 | 1996-05-28 | Union Camp Patent Holding, Inc. | Apparatus for bleaching high consistency pulp with ozone |
| US5174861A (en) * | 1990-10-26 | 1992-12-29 | Union Camp Patent Holdings, Inc. | Method of bleaching high consistency pulp with ozone |
| DE69221385T2 (en) * | 1991-05-24 | 1997-12-11 | Union Camp Patent Holding | Two-stage pulp bleaching reactor and method for bleaching with ozone |
| WO1994015018A1 (en) * | 1992-12-18 | 1994-07-07 | Ingersoll-Rand Company | Method and apparatus for regulating wood pulp bleaching |
| US5810973A (en) * | 1993-09-21 | 1998-09-22 | Beloit Technologies, Inc. | Apparatus for producing small particles from high consistency wood pulp |
| US5554259A (en) * | 1993-10-01 | 1996-09-10 | Union Camp Patent Holdings, Inc. | Reduction of salt scale precipitation by control of process stream Ph and salt concentration |
| FI98836C (en) * | 1994-06-09 | 1997-08-25 | Ahlstroem Pumput Oy | Consistency pulp tower |
| US6007680A (en) * | 1994-12-08 | 1999-12-28 | Kvaerner Pulping Ab | Apparatus for safely conducting pressurized peroxide bleaching |
| US5954066A (en) * | 1995-01-25 | 1999-09-21 | Kvaerner Pulping Ab | Method for controlling chemical reaction |
| US5944952A (en) * | 1995-07-26 | 1999-08-31 | Beloit Technologies, Inc. | Method for bleaching high consistency pulp with a gaseous bleaching reagent |
| FI100011B (en) * | 1996-04-18 | 1997-08-15 | Sulzer Pumpen Ag | Method and apparatus for filling a massager |
| US6077396A (en) * | 1997-05-16 | 2000-06-20 | Lariviere; Christopher J. | Apparatus for fluffing and contacting high consistancy wood pulp with a gaseous bleaching reagent |
| SE514825C2 (en) * | 1999-09-16 | 2001-04-30 | Aga Ab | Oxygen delignification of cellulose pulp with oxidized white liquor as an alkaline source |
| FI20065557A0 (en) | 2006-09-07 | 2006-09-07 | Sulzer Pumpen Ag | Procedure and equipment for filling and cleaning a massager |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2733992A (en) * | 1956-02-07 | reyerson | ||
| US1633735A (en) * | 1925-07-15 | 1927-06-28 | Jr Frederick Knapp Fish | Process and apparatus for making pulp from fibrous material |
| US1669234A (en) * | 1927-04-22 | 1928-05-08 | Chemipulp Process Inc | Process and apparatus for treating fibrous materials for pulping purposes |
| GB684222A (en) * | 1950-07-08 | 1952-12-10 | Kamyr Ab | Cellulose digester |
| US2717195A (en) * | 1954-08-02 | 1955-09-06 | Jackson And Church Company | Method for treating a fibrous material |
| BE681488A (en) * | 1965-10-25 | 1966-10-31 | ||
| US3607618A (en) * | 1967-11-06 | 1971-09-21 | Process Dev Corp | Wood-pulping process |
| US3703435A (en) * | 1967-11-09 | 1972-11-21 | Sunds Ab | Method for finely disintegrating pulp,preferentially cellulose pulp,in connection with the bleaching thereof with gaseous bleaching agent |
| OA03094A (en) * | 1968-07-11 | 1970-12-15 | P P I South African Pulp And P | Improvements to the delignification and bleaching of cellulose pulps with gaseous oxygen. |
| US3654070A (en) * | 1970-04-02 | 1972-04-04 | Sterling Drug Inc | Oxidation and reuse of effluent from oxygen pulping of raw cellulose |
| US3693080A (en) * | 1970-12-21 | 1972-09-19 | Sperry Rand Corp | Time domain measurement of high frequency complex permittivity and permeability of transmission line enclosed material sample |
| US3814664A (en) * | 1972-09-11 | 1974-06-04 | Improved Machinery Inc | Gaseous reaction apparatus including a peripheral gas receiving chamber |
-
1974
- 1974-02-25 US US05/445,212 patent/US3964962A/en not_active Expired - Lifetime
- 1974-12-13 CA CA215,956A patent/CA1037228A/en not_active Expired
-
1975
- 1975-01-17 BR BR335/75A patent/BR7500335A/en unknown
- 1975-02-04 NO NO750349A patent/NO141921B/en unknown
- 1975-02-11 FI FI750370A patent/FI64821C/en not_active IP Right Cessation
- 1975-02-17 SE SE7501737A patent/SE426855C/en not_active IP Right Cessation
- 1975-02-20 DE DE19752507414 patent/DE2507414A1/en active Granted
- 1975-02-25 JP JP50022527A patent/JPS5833012B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5833012B2 (en) | 1983-07-16 |
| SE426855B (en) | 1983-02-14 |
| SE426855C (en) | 1984-06-05 |
| DE2507414A1 (en) | 1975-08-28 |
| NO141921B (en) | 1980-02-25 |
| BR7500335A (en) | 1975-12-02 |
| DE2507414C2 (en) | 1989-04-27 |
| JPS50119771A (en) | 1975-09-19 |
| NO750349L (en) | 1975-08-26 |
| FI64821B (en) | 1983-09-30 |
| FI750370A (en) | 1975-08-26 |
| US3964962A (en) | 1976-06-22 |
| FI64821C (en) | 1984-01-10 |
| SE7501737L (en) | 1975-08-26 |
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