CA1070537A - Method fo feeding fibrous material into a pressurized vessel - Google Patents
Method fo feeding fibrous material into a pressurized vesselInfo
- Publication number
- CA1070537A CA1070537A CA295,514A CA295514A CA1070537A CA 1070537 A CA1070537 A CA 1070537A CA 295514 A CA295514 A CA 295514A CA 1070537 A CA1070537 A CA 1070537A
- Authority
- CA
- Canada
- Prior art keywords
- conduit
- vessel
- compacting
- screw conveyor
- plug
- 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
-
- 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
- D21C7/00—Digesters
- D21C7/06—Feeding devices
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23K—FODDER
- A23K10/00—Animal feeding-stuffs
- A23K10/30—Animal feeding-stuffs from material of plant origin, e.g. roots, seeds or hay; from material of fungal origin, e.g. mushrooms
- A23K10/32—Animal feeding-stuffs from material of plant origin, e.g. roots, seeds or hay; from material of fungal origin, e.g. mushrooms from hydrolysates of wood or straw
-
- 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
- B01J3/00—Processes of utilising sub-atmospheric or super-atmospheric pressure to effect chemical or physical change of matter; Apparatus therefor
- B01J3/02—Feed or outlet devices therefor
-
- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P60/00—Technologies relating to agriculture, livestock or agroalimentary industries
- Y02P60/80—Food processing, e.g. use of renewable energies or variable speed drives in handling, conveying or stacking
- Y02P60/87—Re-use of by-products of food processing for fodder production
Abstract
ABSTRACT OF THE DISCLOSURE
A method of feeding fibrous ligno-cellulose raw material into a pressurized vessel such as a digester operating at approximately 300 pounds per square inch. The raw material is first pre-compacted by a screw conveyor and subsequently compacted to a density of at least 45 pounds per cubic foot of oven dry material to form a plug in a feeding conduit communicating with the digester. During the pre-compacting and compacting stage, the moisture of the material is maintained at a natural level of about 10%
to 50% by weight. The plug thus forms a continuously advancing mass of material which-separates the interior of the digester from the surrounding atmosphere without the need of special valve means normally used in prior art. The advancement of the plug takes place along a straight line generally coincident with the centreline of the screw conveyor but axially spaced from same.
A method of feeding fibrous ligno-cellulose raw material into a pressurized vessel such as a digester operating at approximately 300 pounds per square inch. The raw material is first pre-compacted by a screw conveyor and subsequently compacted to a density of at least 45 pounds per cubic foot of oven dry material to form a plug in a feeding conduit communicating with the digester. During the pre-compacting and compacting stage, the moisture of the material is maintained at a natural level of about 10%
to 50% by weight. The plug thus forms a continuously advancing mass of material which-separates the interior of the digester from the surrounding atmosphere without the need of special valve means normally used in prior art. The advancement of the plug takes place along a straight line generally coincident with the centreline of the screw conveyor but axially spaced from same.
Description
The present invention relates to a method of feeding fibrous ligno-cellulose raw material of the type capable of being conveyed in a screw conveyor into a pressurized vesselJ such as a pressurized digester used in the production of animal fodder, pulping digester, or the like, operating at a vapour medium pressure of up to 300 pounds per square inch. It has long been recognized that it is of advantage if digesters of the above type operate in a continuous man~er.
Continuous digesters have long been known in the art of pulp production. Reference may be had to Canadian patent 610,484, issued December 13, 1960 (H.S. Messing)t Canadian patent 636,473, issued February 13, 1962 (N.H. Sandberg); Canadian patent 66~,307, issued August 27, l9fi3 (F.B.R. Green);
Canadian patent 766,039, iss~ed August 29, 1967 (J.C.F.C.
Richter)~ Canadian patent 788,204, issued June 25, 1968 (A.J. Roerig).
One of the problems of operat~ng continuous digesters is that the pres~urized interior of the digester mu~t be safely insulated from the surrounding atmosphere.
-20 In known prior art, this problem is solved by providing the feeding region of a digester with a special valve di~posed at a suitable location of the feeding system. The valve must be o a heavy duty structure particularly when the digester operates at a relatively high pressure of,say, 300 p.s.i.
The valve is relatively expensi~e to produce. It must be maintained in a perfect operative condition to avoid potential ~erious conse~uences of failure which might result in the blow-back through the feeding system. Another known way of solving the above problem is disclosed in Canadian patent 0 636,473 issued on February 13, 1962 to Sandberg. In this arrangement, the inlet region of an apparatus for pre-soaking - wood chips is provided with an inlet arrangement wherein a
Continuous digesters have long been known in the art of pulp production. Reference may be had to Canadian patent 610,484, issued December 13, 1960 (H.S. Messing)t Canadian patent 636,473, issued February 13, 1962 (N.H. Sandberg); Canadian patent 66~,307, issued August 27, l9fi3 (F.B.R. Green);
Canadian patent 766,039, iss~ed August 29, 1967 (J.C.F.C.
Richter)~ Canadian patent 788,204, issued June 25, 1968 (A.J. Roerig).
One of the problems of operat~ng continuous digesters is that the pres~urized interior of the digester mu~t be safely insulated from the surrounding atmosphere.
-20 In known prior art, this problem is solved by providing the feeding region of a digester with a special valve di~posed at a suitable location of the feeding system. The valve must be o a heavy duty structure particularly when the digester operates at a relatively high pressure of,say, 300 p.s.i.
The valve is relatively expensi~e to produce. It must be maintained in a perfect operative condition to avoid potential ~erious conse~uences of failure which might result in the blow-back through the feeding system. Another known way of solving the above problem is disclosed in Canadian patent 0 636,473 issued on February 13, 1962 to Sandberg. In this arrangement, the inlet region of an apparatus for pre-soaking - wood chips is provided with an inlet arrangement wherein a
- 2 -hopper for d~y chips is separated by a rotary valve from a pre-soaking apparatus of the type of a screw conveyor whose outlet is tapered to compress the pre-soaked chips to the density of approximately 25 pounds per cubic foot to form a ~plug~ which is further advanced into an impregnating chamber operating at about 170 p.s.i., the advancing plu~
forming a barrier separating the pre-soaking chamber from the impregnating chamber. Even though the latter arrangement i8 based on recognition of the action of a compacted ~plug"
of wood chips, it still reauires the valve upstream of the screw conveyor as the plug of pre-soa~ed chips is relatively unstable and tends to blow back, particularly if the delivery of further chips form the upstream end of the plug is interrupted for any reason.
Fibrous ligno-cellulose raw material such as wood chips, straw or baga6se are fed into a continuous digester by a screw conveyor which i~ only capable to compact the material to a degree not e _ the fibre~ of the material become sheared ~etween periphery of the feed~ng screw helix and longitudinal ribs normhlly prov~ded in the housing of the screw conveyor.
It i8 an ob~ect of the present invention to overcome the above drawbacksby a new and useful method of feeding the above material into a pressurized vessel.
According to the invention and in general terms, the material is first deliYered in a generally free-fall bulk form into an inlet region of a screw conveyor whereupon it is advanced by the screw conveyor to an outlet region thereof and is pre-- compacted to a first degree of compactness. The material is then advanced further in the pre-compacted state into an elong-- ated, tubular conduit generally coaxial with the centreline of the screw conveyor such that the material occupies the entire 1070~37 cross-sectional of a first length of said conduit to cause the interior walls of the conduit to frictionally "drag" the advanc-ing material, whereby the material is eventually compacted to a bulk density of at least 45 pounds per cubic foot of oven dry material to form within the conduit a dry plug advancing through a second length of the conduit. Throughout the pre-compacting and the compacting stage, the material is maintained at its natural moisture content of about 10 to 50% by weight.
Eventually, the leading end of the advancing plug of the material is discharged into the pressurized vessel. The invention thus accomplishes the feeding of a continuous digester with the material in the form of a relatively solid, dry plug which was found to resist penetration by steam of up to 310 p.s.i. to effectively separate the pressurized interior of the digester from the surrounding atmosphere. Accordingly, no valves or the like are required at any portion of the inlet end of the dige~ter.
The pre-compacting of the material i8 only effected to a density which does not result in exceeding the fibre shear limlt within the-screw conveyor area. The fiber shear limit, of course, differs depending on the type of the material. Further compacting of the material to the ~plug" state is preferably effected by a reciprocating pushing movement at a point ~
stream of the screw conveyor combined with a frictional drag at the walls of the conduit through which the material is ~eing advanced. The reciprocating pushing mov~ment is particularly suita~le when the material is of a relatively low fibre shear limit (e.g. straw, bagasse, etc.) ~ o~t~t 4~ Tt was found that it is peo~e~b~e to effect the reciprocating pushing movemRnt along an annular locus whose outside diameter is generally coincident with the inside diameter of the conduit as such action compresses the material such that stress lines in the compressed material assume generally arcuate configurations whose apexes point~
towards the outlet of the conduit into the vessel. Thus, the stress generated within the compacted material affects the beam strength of the compacted material, to reduce the danger of a blow-back of the compacted "plug" within the conduit, due to the pressure in the vessel.
The invention will now be described by way of examples with reference to the accompanying drawings showing two basic types of an apparatus capable of carrying out the method.
In the drawings: ~
Figure 1 is a simplified diagram of a plant for processing a fibrous, lîgno-cellulose material to animal fodder, the facility including one embodiment of the apparatus capable of operating according to the method of the present invention;
Figure 2 is a simplified partial, sectional view of one embodiment of the apparatus capable of operating according to the method of the present invention;
Figure 3 i~ a simplifled plan view of the apparatus ~ shown ~n Figure 2, including accessories such as drive-motor etc., not shown in Figure 2;
Figure~ 4 is a side elevation of the apparatus shown in Figure 3;
Figure 5 i8 a simplified, partial, sectional view similar to Figure 2 but showing another embodiment of an apparatus capable of carrying out the method accordlng to the present invention;
Figure 6 ~s a simplified plan ~iew of the apparatus as shown in Figure 5;
Figure 7 is a side elevation of the apparatus shown in Figure 6;
Figure 8 i~ a variant of detail VIII of Figure 2; and 1~70537 Figure 9 is a simplified flow diagram of a hydraulic system used in driving compacting means of the apparatus as shown in Figures 2 - ~ or Figures 5 - 7.
Figure 1 shows an example of application of the present invention in a fac~lity for converting cellulosic material such as poplar wood chips, straw, bagasse or the like material into nutritious fodder. The ligno-cellulose raw material is of the type of a bulk form capable of being conveyed in a screw conveyor.
Those skilled in the art will appreciate that the material of this type may include a plurality of different lengths of the particles, e.g. from a complete length of straw stalks or stems to chopped straw, the material including wood chips but also different sorts of sawmill rejects it being understood that e.g.
sawdust of so-called saw-flour type is in fact composed of minute particles of wood whose fibers are too short to fall within the scope of the term of "fibrous" material.
The raw material is fed in a generally free-fall bulk form from a hopper A through an outlet B into an inlet region of a ~crew conveyor C. The conveyor C advance~ the material to an outlet region D (Fig. 2) of the conveyor, wherein the material reaches a pre-compacted state of a first degree of compactness which is below the value that would exceed the minimum shear limit of fibres contained in the material. The shear lim~t differs with different material and if exceeded, ~he screw con~eyor would no longer be capable of advancing the material as the material outside ~he periphery of the screw conveyor would separate from the material within the spiral of the screw. Those sk~lled ~n the art will appreciate that the required degree of pre-compacting of the material can be influ-enced by a plurality of factors such as tSe pitch and depth of the¦screw conveyor, the volume and conf~guration of the outlet region, the speed at which t~e pre-compacted material is further 107~537 discharged from the outlet region etc. The adjusting of one or more of the determining factors is most reliably accomplished by the trial-and-error process.
From the outlet region D, the pre-compacted material i5 further advanced into an elongated tubular conduit generally coaxial with the screw conveyor such that the material occupies the entire cross-sectional area of a first length F (Fig. 2) of the conduit E. Near the end of leng~h F, the material beoomes compacted to a bulk density of at least 45 pounds per cubic n foot of oven dry material and advances through a second length G of the conduit E to finally become discharged into a pressur-ized vessel H operatively connected with a steam generator I
which normally maintains the pressure within the vessel R at a value of up to 300 p.s.i., and with a by-product recovery column J as in Figure~l. The material discharged at the outlet of conduit E returns back to a generally free-fall bulk volume state, sub~ect to pressure differential. The vessel H is proYiaed with a further conveyor X for continuous advancing of the processed material towards an outlet L from which the processed material is discharged over a blow valve (not shown) into a blow bin ~. Reference N designates a drive unit of the conveyor X.
As mentioned before, the present invention relates to a new and useful metho~ for feedin~ the above type of raw material into a pressurized vessel such as vessel ~ referred to above, so as to enable a continuous feeding of the material and effectiv~ly preYenting the pressur$zed medium within the ve~sel X to blow back ~nto the area of the screw conveyor B.
It WA8 found out that the "plu~" dens~ty of the magnitude of 45 pounds per cubic foot of oven dry material over a certain length of the portion G is resistant to pressure and ~ s~enm penetration from the pressurized ves~el to a degree ~ 070537 sufficient to effectively close the conduit ~ear the outlet to the pressurized vessel, even if the advancement of the plug is interrupted for any particular reason.
The method according to the invention can best be carried out in an apparatus virtually identical ~th the device disclosed in a copending United States patent application, seria~ number , filed 1976 , entitled Two embodiments of the apparatus will now be described in a greater detail.
Figures 2 - 4 show a first embodiment of the apparatus.
A base frame 1 of the device supports a bearing housing 2 through which passes a shaft 3 protruding from a gear box 4 (not shown in Figure 2) which, as shown in Figure 4 i8 driven by a drive motor 5 over a V-belt drive 6. The free end 7 (Fignre 2) of shaft 3 i9 fixedly secured inside a tubular core 8 of a conveyor screw 9 provided with a continuous helix 10 of .~
a predetermined depth 11 (Figure 2). The helix 10 is arranged to rotate in contact with axially elongated, radially equ~dis-tantly spaced ribs 12 fixedly secured to the inside of a tube 13 forming a part of the path of the screw conveyor. ~he tube ; 13 is surrounded by a hollow p~ston 14 which is movable in a reciprocating fashion-ax~ally of the screw conveyor. The outside diameter of piston 14 is slidably received for reciprocat~ng, telescopic movement within an inlet end of a tubular conduit 15. The face of the piston 14 turned away from the outlet B of the hopper A is provided with a compression ring 16 whose cutside diameter corresponds to that of the piston 14 and whose inside diameter is approx~mately the same as the inside 0 diameter of tube 13.
The conduit 15 is provided with slot~ 17, 18 through - which protrude, radially relative to piston 14, connector members 19, 20, fixedly secured to the piston 14,the outside ends of the members 19, 20 being fixedly secured to slide rods 21, 22, mounted for sliding movement generally parallel with the axis of the screw conveyor, each within a slotted sleeve 23, 24.
One end of each of the rods 21, 22 is hingedly secured to a respective link member 25, 26 associated with the free end of respective piston rod 27, 2g o~ a hydraulic cylinder 29, 30 the respective end of each cylinder bël~ng mounted on a bracket 31, 32 fixedly secured to the frame 1, as be~t seen in figures
forming a barrier separating the pre-soaking chamber from the impregnating chamber. Even though the latter arrangement i8 based on recognition of the action of a compacted ~plug"
of wood chips, it still reauires the valve upstream of the screw conveyor as the plug of pre-soa~ed chips is relatively unstable and tends to blow back, particularly if the delivery of further chips form the upstream end of the plug is interrupted for any reason.
Fibrous ligno-cellulose raw material such as wood chips, straw or baga6se are fed into a continuous digester by a screw conveyor which i~ only capable to compact the material to a degree not e _ the fibre~ of the material become sheared ~etween periphery of the feed~ng screw helix and longitudinal ribs normhlly prov~ded in the housing of the screw conveyor.
It i8 an ob~ect of the present invention to overcome the above drawbacksby a new and useful method of feeding the above material into a pressurized vessel.
According to the invention and in general terms, the material is first deliYered in a generally free-fall bulk form into an inlet region of a screw conveyor whereupon it is advanced by the screw conveyor to an outlet region thereof and is pre-- compacted to a first degree of compactness. The material is then advanced further in the pre-compacted state into an elong-- ated, tubular conduit generally coaxial with the centreline of the screw conveyor such that the material occupies the entire 1070~37 cross-sectional of a first length of said conduit to cause the interior walls of the conduit to frictionally "drag" the advanc-ing material, whereby the material is eventually compacted to a bulk density of at least 45 pounds per cubic foot of oven dry material to form within the conduit a dry plug advancing through a second length of the conduit. Throughout the pre-compacting and the compacting stage, the material is maintained at its natural moisture content of about 10 to 50% by weight.
Eventually, the leading end of the advancing plug of the material is discharged into the pressurized vessel. The invention thus accomplishes the feeding of a continuous digester with the material in the form of a relatively solid, dry plug which was found to resist penetration by steam of up to 310 p.s.i. to effectively separate the pressurized interior of the digester from the surrounding atmosphere. Accordingly, no valves or the like are required at any portion of the inlet end of the dige~ter.
The pre-compacting of the material i8 only effected to a density which does not result in exceeding the fibre shear limlt within the-screw conveyor area. The fiber shear limit, of course, differs depending on the type of the material. Further compacting of the material to the ~plug" state is preferably effected by a reciprocating pushing movement at a point ~
stream of the screw conveyor combined with a frictional drag at the walls of the conduit through which the material is ~eing advanced. The reciprocating pushing mov~ment is particularly suita~le when the material is of a relatively low fibre shear limit (e.g. straw, bagasse, etc.) ~ o~t~t 4~ Tt was found that it is peo~e~b~e to effect the reciprocating pushing movemRnt along an annular locus whose outside diameter is generally coincident with the inside diameter of the conduit as such action compresses the material such that stress lines in the compressed material assume generally arcuate configurations whose apexes point~
towards the outlet of the conduit into the vessel. Thus, the stress generated within the compacted material affects the beam strength of the compacted material, to reduce the danger of a blow-back of the compacted "plug" within the conduit, due to the pressure in the vessel.
The invention will now be described by way of examples with reference to the accompanying drawings showing two basic types of an apparatus capable of carrying out the method.
In the drawings: ~
Figure 1 is a simplified diagram of a plant for processing a fibrous, lîgno-cellulose material to animal fodder, the facility including one embodiment of the apparatus capable of operating according to the method of the present invention;
Figure 2 is a simplified partial, sectional view of one embodiment of the apparatus capable of operating according to the method of the present invention;
Figure 3 i~ a simplifled plan view of the apparatus ~ shown ~n Figure 2, including accessories such as drive-motor etc., not shown in Figure 2;
Figure~ 4 is a side elevation of the apparatus shown in Figure 3;
Figure 5 i8 a simplified, partial, sectional view similar to Figure 2 but showing another embodiment of an apparatus capable of carrying out the method accordlng to the present invention;
Figure 6 ~s a simplified plan ~iew of the apparatus as shown in Figure 5;
Figure 7 is a side elevation of the apparatus shown in Figure 6;
Figure 8 i~ a variant of detail VIII of Figure 2; and 1~70537 Figure 9 is a simplified flow diagram of a hydraulic system used in driving compacting means of the apparatus as shown in Figures 2 - ~ or Figures 5 - 7.
Figure 1 shows an example of application of the present invention in a fac~lity for converting cellulosic material such as poplar wood chips, straw, bagasse or the like material into nutritious fodder. The ligno-cellulose raw material is of the type of a bulk form capable of being conveyed in a screw conveyor.
Those skilled in the art will appreciate that the material of this type may include a plurality of different lengths of the particles, e.g. from a complete length of straw stalks or stems to chopped straw, the material including wood chips but also different sorts of sawmill rejects it being understood that e.g.
sawdust of so-called saw-flour type is in fact composed of minute particles of wood whose fibers are too short to fall within the scope of the term of "fibrous" material.
The raw material is fed in a generally free-fall bulk form from a hopper A through an outlet B into an inlet region of a ~crew conveyor C. The conveyor C advance~ the material to an outlet region D (Fig. 2) of the conveyor, wherein the material reaches a pre-compacted state of a first degree of compactness which is below the value that would exceed the minimum shear limit of fibres contained in the material. The shear lim~t differs with different material and if exceeded, ~he screw con~eyor would no longer be capable of advancing the material as the material outside ~he periphery of the screw conveyor would separate from the material within the spiral of the screw. Those sk~lled ~n the art will appreciate that the required degree of pre-compacting of the material can be influ-enced by a plurality of factors such as tSe pitch and depth of the¦screw conveyor, the volume and conf~guration of the outlet region, the speed at which t~e pre-compacted material is further 107~537 discharged from the outlet region etc. The adjusting of one or more of the determining factors is most reliably accomplished by the trial-and-error process.
From the outlet region D, the pre-compacted material i5 further advanced into an elongated tubular conduit generally coaxial with the screw conveyor such that the material occupies the entire cross-sectional area of a first length F (Fig. 2) of the conduit E. Near the end of leng~h F, the material beoomes compacted to a bulk density of at least 45 pounds per cubic n foot of oven dry material and advances through a second length G of the conduit E to finally become discharged into a pressur-ized vessel H operatively connected with a steam generator I
which normally maintains the pressure within the vessel R at a value of up to 300 p.s.i., and with a by-product recovery column J as in Figure~l. The material discharged at the outlet of conduit E returns back to a generally free-fall bulk volume state, sub~ect to pressure differential. The vessel H is proYiaed with a further conveyor X for continuous advancing of the processed material towards an outlet L from which the processed material is discharged over a blow valve (not shown) into a blow bin ~. Reference N designates a drive unit of the conveyor X.
As mentioned before, the present invention relates to a new and useful metho~ for feedin~ the above type of raw material into a pressurized vessel such as vessel ~ referred to above, so as to enable a continuous feeding of the material and effectiv~ly preYenting the pressur$zed medium within the ve~sel X to blow back ~nto the area of the screw conveyor B.
It WA8 found out that the "plu~" dens~ty of the magnitude of 45 pounds per cubic foot of oven dry material over a certain length of the portion G is resistant to pressure and ~ s~enm penetration from the pressurized ves~el to a degree ~ 070537 sufficient to effectively close the conduit ~ear the outlet to the pressurized vessel, even if the advancement of the plug is interrupted for any particular reason.
The method according to the invention can best be carried out in an apparatus virtually identical ~th the device disclosed in a copending United States patent application, seria~ number , filed 1976 , entitled Two embodiments of the apparatus will now be described in a greater detail.
Figures 2 - 4 show a first embodiment of the apparatus.
A base frame 1 of the device supports a bearing housing 2 through which passes a shaft 3 protruding from a gear box 4 (not shown in Figure 2) which, as shown in Figure 4 i8 driven by a drive motor 5 over a V-belt drive 6. The free end 7 (Fignre 2) of shaft 3 i9 fixedly secured inside a tubular core 8 of a conveyor screw 9 provided with a continuous helix 10 of .~
a predetermined depth 11 (Figure 2). The helix 10 is arranged to rotate in contact with axially elongated, radially equ~dis-tantly spaced ribs 12 fixedly secured to the inside of a tube 13 forming a part of the path of the screw conveyor. ~he tube ; 13 is surrounded by a hollow p~ston 14 which is movable in a reciprocating fashion-ax~ally of the screw conveyor. The outside diameter of piston 14 is slidably received for reciprocat~ng, telescopic movement within an inlet end of a tubular conduit 15. The face of the piston 14 turned away from the outlet B of the hopper A is provided with a compression ring 16 whose cutside diameter corresponds to that of the piston 14 and whose inside diameter is approx~mately the same as the inside 0 diameter of tube 13.
The conduit 15 is provided with slot~ 17, 18 through - which protrude, radially relative to piston 14, connector members 19, 20, fixedly secured to the piston 14,the outside ends of the members 19, 20 being fixedly secured to slide rods 21, 22, mounted for sliding movement generally parallel with the axis of the screw conveyor, each within a slotted sleeve 23, 24.
One end of each of the rods 21, 22 is hingedly secured to a respective link member 25, 26 associated with the free end of respective piston rod 27, 2g o~ a hydraulic cylinder 29, 30 the respective end of each cylinder bël~ng mounted on a bracket 31, 32 fixedly secured to the frame 1, as be~t seen in figures
3 and 4.
The drive system of each of the cylinders 29 and 30 : i8 not shown in figures 2 - 4 but is indicated by way of a flow diagram in figure 9.
The system includes a high volume pump 33 whose discharge communicates o~er a check valve 34 with line 35 commun-icating with one side of a flow control valve 36, the other side of the valve 36 being in communication with piston actuator lines 37, 38. Coupled with the high Yolume pump 33 is a low volume high pressure pump 39 which operates at a pressure of 1500 to 3000 p.s.i. The low-volumej high pressure pump -39 also communicates with the line 35 and with the assoc~ated portions as referred to hereinabove. A branch line 40 i8 disposed between the h~gh volume pump 33 and the chec~ valve 34, to communicate, over a pilot valve 41 with sump 42 of the system.
Branched off the line 35 is a pilot line 43 whose one end commun~cates with the pilot valve 41.
When.pumps 33 and 3~ are driven and assuming there is virtually no resistance to be overcome by the hydraulic cylinder 29 or 3~, the pressure generated by the high volume pump is sufficient to open the chec~ valve 34 and to deliver the pressurized fluid to the flow control valve 36. The pilot valve 41 i~ closed and, in the position shown ~n figure 9, the hydraulic fluid is delivered throught the valve 36 to the sump 42. On switching the flow control valve 36 to an "on" position, the hydraulic fluid flows through the piston actuation line 37 to the left-hand side of piston P while the line 38 now communicates through valve 36 with the sump 42. The piston P is driven to the right-hand side of cylinder 29, 30 thus driving the piston rod 27, 28. When the piston P reaches its right hand side limit, the control valve 36 i8 triggered to reverse the flow in lines 37 and 38 to thus cause the movement of piston P back to the left-hand side. As the fibrous ligno-cellulose raw material accumulates in the conduit E, the pressure acting against the compressive movement of piston rod 27, 28 increases until it ,~ reaches a point at which the pressure developed by the high volume pump 33 is no longer capable of open~ng the check valve 34. At this po~nt, the pilot line 43 transfers a pressure ; signal to the pilot ~alve 41 to actuate same such that the fluid di~charged by the high volume pump 33 is transferred through line 40 to the ~ump 42. At this point, it is only the low volume, high pressure pump 39 that operates the B~stem of the cylinder 29, 30. Normally, one complete back-and-forth stroke of piston ~' P i8 effected within approximately one second. The system i8, of course, provided by a rel~ef line 44 providea wlth a relief valve ~not shown).
The above hydraulic system is suitably associated with the circuit ~not shown3 of the drive motor 5 in a known manner such that both systems operate simultaneously.
The operation of the device shown in figures 2 - 4 will now be described with reference to fiqure 2 and particularly to the diagram section thereof showing the compacting of the material. The ligno-cellulose raw material enters, in a generally free-fall bulk form the inlet region B of the screw conveyor ~.
- As the screw conveyor advances the material through tube 13, an~
assuming that piston 14 is in its extended position (dotted lines in Figure 2), the material is conveyed and gradually compacted by the action of the screw conveyor and also due to accumulation of the material at the outlet region D of the screw conveyor, to reach an increased density at 46. As the piston 14 moves back-wards, an instant increase in the density occurs at the outset of the movement (points 46 - 47), followed by a further gradual increase shown between points 47 and 4~ of the diagram. As the material leaves the area of the inside of the ring 16 at the face of piston 14, a rebound takes place (48 - 49) due to the fact that the material enters the first length F of the conduit 15.
The rebound results in a slight decrease in the density of the pre-compacted material, as shown by the line between points 48 and 49. The subsequent forward movement of piston 14 further aavances the material through the length F of the conduit 15.
Due to the friction at the wall of the conduit 15, the material becomes gradually compacted to a high degree. The frict~onal effect of the wall of conduit 15 is further enhanced by friction vanes 53 which restrict the cro~s-sect~onal area of the conduit ~' to assist in regulating the compacting of the material at varying material~feed rates. Eventually, the compactnes~ of the material reaches the value corresponding to point 50 of the diagram. The line 50-51 designates a slight decrease in ~ensity, also referred to as "reboundn, which occurs as the piston 14 retract~. The material advances through the remaining length G of conduit 15 at a uniform compactness, as shown ~y the line connecting point~ 51 and 52.
In general terms, the~ul~ at point 45 ~ 8 generally free-fall bu~k form. Point 48 designates the density at which fibre shear occurs at the conveyor screw, while the level of point 51 corresponds to a density wherein the msterial - hs~ at least 45 pound8 per cubic foot of oven dry material. ~t 1~70537 wag found out that the latter compactness is sufficient to prevent the pressurized steam from vessel H to enter the conduit 15. Thus the advancing "plug" within region G of the conduit 15 forms a continuous closure means, thus eliminating the need of any additional valves or the like.
: At the outlet of conduit 15 into the vessel H the material drops back to the free-fall volume subject to pressure differential.
The method according to the present invention was tested with a device similar to that shown in figures 2 - 4.
The operative conditions have been found to be as follows:
Processea Material Straw Poplar Wood ". Out~ide diameter of the screw conv~yor 5~ 5 '~ Out~i~e diameter o~ the core of the screw aonveyor 2~ 2 Inside-diameter of~the conduit 15 8~ 8 Length of section F of the conduit18" 18"
Length of section G of the conduit6~ 6 Pitch of the helix 10 2-1/2" 2-1/2 Inside diameter of the ring 16 5-1/2" 5-1/2 Length of stroke of piston 14 3~ 3"
Density at point 48 (in pounds per cub~c foot of oven dry material) 10 15 Density at point 51 (in pounds per cubic foot of oven ary material) 46 54 Number of $trokes of p~ston 14 2 per sec 1 per sec Speed of oonveyor 9 250 rpm 150 rpm Length of piston 14 7-1/2~ 7-1/2~
It will be observea from the above that only some of the figure~ of operation of the device have to be modlfied depend~ng on the type of the con~eyed material. It wlll further be appreciated that the point 51 of co~pactness is prefer-ably achieved solely ~y the reciprocating action of piston 14, pa~ticularly when a low-strength fibre materi~l such a8 straw is :1070537 being supplied to the pressurized vessel. On the other hand, it was found that certain materials, e.g. hardwood, have the fibre shear limit value high enough to make it possible to achieve the "plug" compactness solely by the action of the screw conveyor, without the need for a reciprocating piston. Of course, such arrangement of the device requires much stronger overall arrangement of the screw conveyor assembly. Therefore, it is preferred to gen-erate the "plug" compacting pressure by subjecting the material within the conduit to a repeated intermittent compressive force oriented in axial direct~on towards the vessel H, the compressive force being applied to said material near the end of said conduit 15 remote from the vessel ~.
Another type of apparatus suitable for carrying the method according to the present invention ig shown in Figure~ 5 - 7. It has a base frame 60 to whose left hand side is flxedly secured a bracket 61 supporting, by way of a pivot pin 62 one end of a hydraulic cylinder 63 whose piston rod mechanism ~ncludes a l~nk member 64 connected to a reciprocating rod 65 slidably secured in a housing 66 ~uppported on the frame 60. As best seen from figure 6, the rod 65 passes through a tubular piston housing 67. The free end of rod 65 is secured to a cylindric piston 68. Accordingly, with the operation of the cylinder 63, the piston 68 can be moved back and forth, the piston being guided by an enlarged diameter recess in the piston housing 67 ~8 shown in figure 5. The same figure shows that the face of piston 68 has a central depression. Accord~ngly, the forwardmost portion of the face of the piston 68 is of an annular configuration.
A portion of the piston housing 67 is surroundea by a sleeve 69 which is rotatable about the piston housing 67 and i8 supported by a ball bearing assem~ly fixedly secured to one end of the sleeve 69 is a sprocket gear 71 for rotatably driving the sleeve 69. The sleeve 69 forms the core of a con-107~3537 veyor screw 72 provided with a helix 73 as shown. The free end of the conveyor 72 is surrounded by a tubular housing 74 having an outlet end of the shape of a frusto-conical chamber 75 whose minor base end communicates with a conduit E of generally the same configuration as the conduit of the embodiment shown in figures 2 - 4. The conduit E is provided with friction vanes similar to the vanes as shown in figure 2 or in figure 8.
It will be appreciated that the device operates in generally the same fashion as the previously described embodiment in that the screw conveyor receives generally loose material pre-compacts the material and advances it into the chamber 75 from which the material is further conveyed and compacted by the reciprocating action of piston 68. The face of piston 68 travels to a distance closely spaced from the inlet of tubular conduit E ~8 shown in broken lines in figure S.
Turning now to ~igure 8 and with reference to figure 2, figure 8 ~hows one embodiment of ad~ustable friction vanes 53 ln a schematic detail of a preferred embodiment. The conduit 15 i8 provided with a plurality of elongated slots 8~ e~uidistant- !
ly spaced from each other in peripheral direction. Each slot 80 receives a flat, segmental plate 81 which closely fit~
within the slot 80 for a sliding movement there$n. The upper portion of the plate 81 is guided in a housing 82 whose top receives a set screw 83 engaging the upper edge of the plate 81 and determining the depth of penetration of the retaining edge 84 of segment 81 into the interior of conduit 15. The annular housing 8~ i6, of course, fixedly secured to the exterior of conduit 15 by welding.
It w~ll be appreciatea fr the above descr~ption of figure 8 that simple manipulating of set screws 85 will result in a deeper or shallower penetration of the edge 86 into the conduit 15 with a resulting greater or lesser increase in 107al537 the frictional force imparted to the advancing material proceeding from the left to the right of figure 8.
Those s~illed in the art will readily conceive further ways of effecting the method according to the presènt invention differing from the above disclosure but still falling within the scope of the following claims.
The drive system of each of the cylinders 29 and 30 : i8 not shown in figures 2 - 4 but is indicated by way of a flow diagram in figure 9.
The system includes a high volume pump 33 whose discharge communicates o~er a check valve 34 with line 35 commun-icating with one side of a flow control valve 36, the other side of the valve 36 being in communication with piston actuator lines 37, 38. Coupled with the high Yolume pump 33 is a low volume high pressure pump 39 which operates at a pressure of 1500 to 3000 p.s.i. The low-volumej high pressure pump -39 also communicates with the line 35 and with the assoc~ated portions as referred to hereinabove. A branch line 40 i8 disposed between the h~gh volume pump 33 and the chec~ valve 34, to communicate, over a pilot valve 41 with sump 42 of the system.
Branched off the line 35 is a pilot line 43 whose one end commun~cates with the pilot valve 41.
When.pumps 33 and 3~ are driven and assuming there is virtually no resistance to be overcome by the hydraulic cylinder 29 or 3~, the pressure generated by the high volume pump is sufficient to open the chec~ valve 34 and to deliver the pressurized fluid to the flow control valve 36. The pilot valve 41 i~ closed and, in the position shown ~n figure 9, the hydraulic fluid is delivered throught the valve 36 to the sump 42. On switching the flow control valve 36 to an "on" position, the hydraulic fluid flows through the piston actuation line 37 to the left-hand side of piston P while the line 38 now communicates through valve 36 with the sump 42. The piston P is driven to the right-hand side of cylinder 29, 30 thus driving the piston rod 27, 28. When the piston P reaches its right hand side limit, the control valve 36 i8 triggered to reverse the flow in lines 37 and 38 to thus cause the movement of piston P back to the left-hand side. As the fibrous ligno-cellulose raw material accumulates in the conduit E, the pressure acting against the compressive movement of piston rod 27, 28 increases until it ,~ reaches a point at which the pressure developed by the high volume pump 33 is no longer capable of open~ng the check valve 34. At this po~nt, the pilot line 43 transfers a pressure ; signal to the pilot ~alve 41 to actuate same such that the fluid di~charged by the high volume pump 33 is transferred through line 40 to the ~ump 42. At this point, it is only the low volume, high pressure pump 39 that operates the B~stem of the cylinder 29, 30. Normally, one complete back-and-forth stroke of piston ~' P i8 effected within approximately one second. The system i8, of course, provided by a rel~ef line 44 providea wlth a relief valve ~not shown).
The above hydraulic system is suitably associated with the circuit ~not shown3 of the drive motor 5 in a known manner such that both systems operate simultaneously.
The operation of the device shown in figures 2 - 4 will now be described with reference to fiqure 2 and particularly to the diagram section thereof showing the compacting of the material. The ligno-cellulose raw material enters, in a generally free-fall bulk form the inlet region B of the screw conveyor ~.
- As the screw conveyor advances the material through tube 13, an~
assuming that piston 14 is in its extended position (dotted lines in Figure 2), the material is conveyed and gradually compacted by the action of the screw conveyor and also due to accumulation of the material at the outlet region D of the screw conveyor, to reach an increased density at 46. As the piston 14 moves back-wards, an instant increase in the density occurs at the outset of the movement (points 46 - 47), followed by a further gradual increase shown between points 47 and 4~ of the diagram. As the material leaves the area of the inside of the ring 16 at the face of piston 14, a rebound takes place (48 - 49) due to the fact that the material enters the first length F of the conduit 15.
The rebound results in a slight decrease in the density of the pre-compacted material, as shown by the line between points 48 and 49. The subsequent forward movement of piston 14 further aavances the material through the length F of the conduit 15.
Due to the friction at the wall of the conduit 15, the material becomes gradually compacted to a high degree. The frict~onal effect of the wall of conduit 15 is further enhanced by friction vanes 53 which restrict the cro~s-sect~onal area of the conduit ~' to assist in regulating the compacting of the material at varying material~feed rates. Eventually, the compactnes~ of the material reaches the value corresponding to point 50 of the diagram. The line 50-51 designates a slight decrease in ~ensity, also referred to as "reboundn, which occurs as the piston 14 retract~. The material advances through the remaining length G of conduit 15 at a uniform compactness, as shown ~y the line connecting point~ 51 and 52.
In general terms, the~ul~ at point 45 ~ 8 generally free-fall bu~k form. Point 48 designates the density at which fibre shear occurs at the conveyor screw, while the level of point 51 corresponds to a density wherein the msterial - hs~ at least 45 pound8 per cubic foot of oven dry material. ~t 1~70537 wag found out that the latter compactness is sufficient to prevent the pressurized steam from vessel H to enter the conduit 15. Thus the advancing "plug" within region G of the conduit 15 forms a continuous closure means, thus eliminating the need of any additional valves or the like.
: At the outlet of conduit 15 into the vessel H the material drops back to the free-fall volume subject to pressure differential.
The method according to the present invention was tested with a device similar to that shown in figures 2 - 4.
The operative conditions have been found to be as follows:
Processea Material Straw Poplar Wood ". Out~ide diameter of the screw conv~yor 5~ 5 '~ Out~i~e diameter o~ the core of the screw aonveyor 2~ 2 Inside-diameter of~the conduit 15 8~ 8 Length of section F of the conduit18" 18"
Length of section G of the conduit6~ 6 Pitch of the helix 10 2-1/2" 2-1/2 Inside diameter of the ring 16 5-1/2" 5-1/2 Length of stroke of piston 14 3~ 3"
Density at point 48 (in pounds per cub~c foot of oven dry material) 10 15 Density at point 51 (in pounds per cubic foot of oven ary material) 46 54 Number of $trokes of p~ston 14 2 per sec 1 per sec Speed of oonveyor 9 250 rpm 150 rpm Length of piston 14 7-1/2~ 7-1/2~
It will be observea from the above that only some of the figure~ of operation of the device have to be modlfied depend~ng on the type of the con~eyed material. It wlll further be appreciated that the point 51 of co~pactness is prefer-ably achieved solely ~y the reciprocating action of piston 14, pa~ticularly when a low-strength fibre materi~l such a8 straw is :1070537 being supplied to the pressurized vessel. On the other hand, it was found that certain materials, e.g. hardwood, have the fibre shear limit value high enough to make it possible to achieve the "plug" compactness solely by the action of the screw conveyor, without the need for a reciprocating piston. Of course, such arrangement of the device requires much stronger overall arrangement of the screw conveyor assembly. Therefore, it is preferred to gen-erate the "plug" compacting pressure by subjecting the material within the conduit to a repeated intermittent compressive force oriented in axial direct~on towards the vessel H, the compressive force being applied to said material near the end of said conduit 15 remote from the vessel ~.
Another type of apparatus suitable for carrying the method according to the present invention ig shown in Figure~ 5 - 7. It has a base frame 60 to whose left hand side is flxedly secured a bracket 61 supporting, by way of a pivot pin 62 one end of a hydraulic cylinder 63 whose piston rod mechanism ~ncludes a l~nk member 64 connected to a reciprocating rod 65 slidably secured in a housing 66 ~uppported on the frame 60. As best seen from figure 6, the rod 65 passes through a tubular piston housing 67. The free end of rod 65 is secured to a cylindric piston 68. Accordingly, with the operation of the cylinder 63, the piston 68 can be moved back and forth, the piston being guided by an enlarged diameter recess in the piston housing 67 ~8 shown in figure 5. The same figure shows that the face of piston 68 has a central depression. Accord~ngly, the forwardmost portion of the face of the piston 68 is of an annular configuration.
A portion of the piston housing 67 is surroundea by a sleeve 69 which is rotatable about the piston housing 67 and i8 supported by a ball bearing assem~ly fixedly secured to one end of the sleeve 69 is a sprocket gear 71 for rotatably driving the sleeve 69. The sleeve 69 forms the core of a con-107~3537 veyor screw 72 provided with a helix 73 as shown. The free end of the conveyor 72 is surrounded by a tubular housing 74 having an outlet end of the shape of a frusto-conical chamber 75 whose minor base end communicates with a conduit E of generally the same configuration as the conduit of the embodiment shown in figures 2 - 4. The conduit E is provided with friction vanes similar to the vanes as shown in figure 2 or in figure 8.
It will be appreciated that the device operates in generally the same fashion as the previously described embodiment in that the screw conveyor receives generally loose material pre-compacts the material and advances it into the chamber 75 from which the material is further conveyed and compacted by the reciprocating action of piston 68. The face of piston 68 travels to a distance closely spaced from the inlet of tubular conduit E ~8 shown in broken lines in figure S.
Turning now to ~igure 8 and with reference to figure 2, figure 8 ~hows one embodiment of ad~ustable friction vanes 53 ln a schematic detail of a preferred embodiment. The conduit 15 i8 provided with a plurality of elongated slots 8~ e~uidistant- !
ly spaced from each other in peripheral direction. Each slot 80 receives a flat, segmental plate 81 which closely fit~
within the slot 80 for a sliding movement there$n. The upper portion of the plate 81 is guided in a housing 82 whose top receives a set screw 83 engaging the upper edge of the plate 81 and determining the depth of penetration of the retaining edge 84 of segment 81 into the interior of conduit 15. The annular housing 8~ i6, of course, fixedly secured to the exterior of conduit 15 by welding.
It w~ll be appreciatea fr the above descr~ption of figure 8 that simple manipulating of set screws 85 will result in a deeper or shallower penetration of the edge 86 into the conduit 15 with a resulting greater or lesser increase in 107al537 the frictional force imparted to the advancing material proceeding from the left to the right of figure 8.
Those s~illed in the art will readily conceive further ways of effecting the method according to the presènt invention differing from the above disclosure but still falling within the scope of the following claims.
Claims (4)
1. Method of feeding fibrous ligno-cellulose raw material through a tubular conduit into a vessel whose interior contains steam pressurized to the range of up to 300 pounds per square inch, said method including the step of compacting said material within a predetermined length of said conduit adjacent to said vessel to a density of at least 45 pounds per cubic foot of oven dry material, while maintaining the moisture thereof at approximately 10 to 50% by weight, simultaneously advancing the compacted material through said length of said conduit to discharge the leading end thereof into said vessel;
whereby the compacted material located within said pre-determined length of the conduit forms a closure plug for preventing the escape of pressurized medium from said vessel into said conduit.
whereby the compacted material located within said pre-determined length of the conduit forms a closure plug for preventing the escape of pressurized medium from said vessel into said conduit.
2. Method of feeding fibrous, ligno-cellulose raw material of the type capable of being conveyed in a screw conv-eyor into a pressurized vessel, said vessel containing vapour medium pressurized to approximately 300 pounds per square inch, said method comprising the steps of:
(a) feeding said material in a generally free-fall bulk form into an inlet region of a screw conveyor;
(b) advancing said material by said screw conveyor to an outlet region of said screw conveyor while simultaneously pre-compacting said material at said outlet region to a first degree of compactness;
(c) further advancing said pre-compacted material in a direction generally co-axial with said screw conveyor, into an elongated, tubular conduit such that the material occupies the entire cross-sectional area of a first length of said conduit;
(d) further compacting the material located in said length of said conduit, to a bulk density of at least 45 pounds per cubic foot of oven dry material;
(e) the moisture content of said material throughout said pre-compacting and said compacting stage being maintained at a natural level of approximately 10 to 50% by weight;
(f) further advancing said material through said conduit towards said vessel, at said bulk density of at least 45 pounds per cubic foot of oven dry material, to form from said material a plug advancing through a second length of said conduit; and (g) discharging the leading end of said plug into said pressurized vessel, whereby said plug forms in said conduit a closure separating, in a pressure-tight fashion, the inside of said vessel from said first length of said conduit.
(a) feeding said material in a generally free-fall bulk form into an inlet region of a screw conveyor;
(b) advancing said material by said screw conveyor to an outlet region of said screw conveyor while simultaneously pre-compacting said material at said outlet region to a first degree of compactness;
(c) further advancing said pre-compacted material in a direction generally co-axial with said screw conveyor, into an elongated, tubular conduit such that the material occupies the entire cross-sectional area of a first length of said conduit;
(d) further compacting the material located in said length of said conduit, to a bulk density of at least 45 pounds per cubic foot of oven dry material;
(e) the moisture content of said material throughout said pre-compacting and said compacting stage being maintained at a natural level of approximately 10 to 50% by weight;
(f) further advancing said material through said conduit towards said vessel, at said bulk density of at least 45 pounds per cubic foot of oven dry material, to form from said material a plug advancing through a second length of said conduit; and (g) discharging the leading end of said plug into said pressurized vessel, whereby said plug forms in said conduit a closure separating, in a pressure-tight fashion, the inside of said vessel from said first length of said conduit.
3. Method as claimed in claim 2, wherein the degree of a compacting pressure acting on said material during said stage of pre-compacting is gradually increased from a generally free-fall bulk pressure to a pressure below the value of a minimum shear limit of fibres contained in said material, whereby said pre-compacting can be effected by screw conveyor means.
4. A method as claimed in claim 3, wherein said compacting pressure is generated by subjecting the material within said conduit to a repeated intermittent compressive force oriented coaxially with said screw conveyor in the direction towards said vessel, while subjecting the material to a frictionally retarding action near the walls of said conduit, said intermittent compressive force being applied to said material near the end of said conduit remote from said vessel and along an annular locus whose outside diameter is generally coincident with the inside diameter of said conduit.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US76209477A | 1977-01-24 | 1977-01-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1070537A true CA1070537A (en) | 1980-01-29 |
Family
ID=25064104
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA295,514A Expired CA1070537A (en) | 1977-01-24 | 1978-01-24 | Method fo feeding fibrous material into a pressurized vessel |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS53111102A (en) |
| AU (1) | AU3269278A (en) |
| BE (1) | BE863159A (en) |
| CA (1) | CA1070537A (en) |
| DE (1) | DE2714993C3 (en) |
| DK (1) | DK33078A (en) |
| ES (1) | ES466296A1 (en) |
| FR (1) | FR2378125A1 (en) |
| GB (1) | GB1599092A (en) |
| SE (1) | SE7800730L (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4798651A (en) * | 1987-03-24 | 1989-01-17 | Stake Technology Ltd. | Process for preparing pulp for paper making |
| US6413362B1 (en) | 1999-11-24 | 2002-07-02 | Kimberly-Clark Worldwide, Inc. | Method of steam treating low yield papermaking fibers to produce a permanent curl |
| US6506282B2 (en) | 1998-12-30 | 2003-01-14 | Kimberly-Clark Worldwide, Inc. | Steam explosion treatment with addition of chemicals |
| DE19983882B4 (en) * | 1998-12-30 | 2007-12-06 | Neenah Paper, Inc. (n.d.Ges.d. Staates Delaware) | Fiber material with high specific volume, high strength and permanent fiber morphology |
| US8449680B2 (en) | 2008-07-24 | 2013-05-28 | Mascoma Canada Inc. | Method and apparatus for treating a cellulosic feedstock |
| US8545633B2 (en) | 2009-08-24 | 2013-10-01 | Abengoa Bioenergy New Technologies, Inc. | Method for producing ethanol and co-products from cellulosic biomass |
| US8778084B2 (en) | 2008-07-24 | 2014-07-15 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for treating a cellulosic feedstock |
| US8900370B2 (en) | 2008-07-24 | 2014-12-02 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US8911557B2 (en) | 2008-07-24 | 2014-12-16 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US8915644B2 (en) | 2008-07-24 | 2014-12-23 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US9004742B2 (en) | 2009-01-23 | 2015-04-14 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US9010522B2 (en) | 2008-07-24 | 2015-04-21 | Abengoa Bioenergy New Technologies, Llc | Method and apparatus for conveying a cellulosic feedstock |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4119025A (en) * | 1977-01-24 | 1978-10-10 | Stake Technology Ltd. | Method and apparatus for conveying particulate material |
| AT398587B (en) * | 1992-02-04 | 1994-12-27 | Oesterreichische Homogenholz A | INPUT PROCEDURE |
| WO1996005365A1 (en) * | 1994-08-11 | 1996-02-22 | Beloit Technologies, Inc. | Means for gas-sealingly conveying shredded pulp |
| AU3032899A (en) | 1998-03-13 | 1999-10-11 | Rhodia Acetow Aktiengesellschaft | Device, method and pressurized reactor for the treatment of solids with liquefied gases under pressure |
| DE10139128A1 (en) * | 2001-08-09 | 2003-02-27 | Herbert Georg Nopper | Device and method for vacuum impregnation |
| SE537758C2 (en) * | 2013-02-22 | 2015-10-13 | Valmet Oy | Screw conveyor for lignocellulose-containing material |
| CN103726381A (en) * | 2013-12-30 | 2014-04-16 | 中冶美利纸业股份有限公司 | Continuous-cooking dehydration system of spiral feeder |
-
1977
- 1977-04-04 DE DE2714993A patent/DE2714993C3/en not_active Expired
-
1978
- 1978-01-20 BE BE184521A patent/BE863159A/en unknown
- 1978-01-20 SE SE7800730A patent/SE7800730L/en unknown
- 1978-01-23 GB GB2574/78A patent/GB1599092A/en not_active Expired
- 1978-01-23 FR FR7801821A patent/FR2378125A1/en not_active Withdrawn
- 1978-01-23 DK DK33078A patent/DK33078A/en unknown
- 1978-01-24 JP JP587078A patent/JPS53111102A/en active Pending
- 1978-01-24 CA CA295,514A patent/CA1070537A/en not_active Expired
- 1978-01-24 ES ES466296A patent/ES466296A1/en not_active Expired
- 1978-01-24 AU AU32692/78A patent/AU3269278A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4798651A (en) * | 1987-03-24 | 1989-01-17 | Stake Technology Ltd. | Process for preparing pulp for paper making |
| US6506282B2 (en) | 1998-12-30 | 2003-01-14 | Kimberly-Clark Worldwide, Inc. | Steam explosion treatment with addition of chemicals |
| DE19983882B4 (en) * | 1998-12-30 | 2007-12-06 | Neenah Paper, Inc. (n.d.Ges.d. Staates Delaware) | Fiber material with high specific volume, high strength and permanent fiber morphology |
| US6413362B1 (en) | 1999-11-24 | 2002-07-02 | Kimberly-Clark Worldwide, Inc. | Method of steam treating low yield papermaking fibers to produce a permanent curl |
| US8778084B2 (en) | 2008-07-24 | 2014-07-15 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for treating a cellulosic feedstock |
| US8449680B2 (en) | 2008-07-24 | 2013-05-28 | Mascoma Canada Inc. | Method and apparatus for treating a cellulosic feedstock |
| US8900370B2 (en) | 2008-07-24 | 2014-12-02 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US8911557B2 (en) | 2008-07-24 | 2014-12-16 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US8915644B2 (en) | 2008-07-24 | 2014-12-23 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US9010522B2 (en) | 2008-07-24 | 2015-04-21 | Abengoa Bioenergy New Technologies, Llc | Method and apparatus for conveying a cellulosic feedstock |
| US9004742B2 (en) | 2009-01-23 | 2015-04-14 | Abengoa Bioenergy New Technologies, Llc. | Method and apparatus for conveying a cellulosic feedstock |
| US8545633B2 (en) | 2009-08-24 | 2013-10-01 | Abengoa Bioenergy New Technologies, Inc. | Method for producing ethanol and co-products from cellulosic biomass |
| US9335043B2 (en) | 2009-08-24 | 2016-05-10 | Abengoa Bioenergy New Technologies, Inc. | Method for producing ethanol and co-products from cellulosic biomass |
Also Published As
| Publication number | Publication date |
|---|---|
| AU3269278A (en) | 1979-08-02 |
| FR2378125A1 (en) | 1978-08-18 |
| DE2714993A1 (en) | 1978-07-27 |
| SE7800730L (en) | 1978-07-25 |
| JPS53111102A (en) | 1978-09-28 |
| DK33078A (en) | 1978-07-25 |
| DE2714993C3 (en) | 1979-08-16 |
| BE863159A (en) | 1978-05-16 |
| GB1599092A (en) | 1981-09-30 |
| ES466296A1 (en) | 1978-10-01 |
| DE2714993B2 (en) | 1978-12-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1070537A (en) | Method fo feeding fibrous material into a pressurized vessel | |
| US4119025A (en) | Method and apparatus for conveying particulate material | |
| US4632795A (en) | Method and apparatus for extrusion processing of cellulose bearing materials | |
| US4186658A (en) | Apparatus for conveying particulate material | |
| CA1138708A (en) | Press for expressing liquid from a mass | |
| US4283252A (en) | Method and apparatus for producing fiber pulp from fibrous lignocellulose containing material | |
| EP0689376B1 (en) | Baling machine | |
| NO790243L (en) | PROCEDURE AND DEVICE FOR DIVISION OF FIBER-CONTAINING, COMPRESSIBLE MATERIALS, AT THE SAME TIME AS THESE ARE TRANSPORTED FROM A PLANT WITH A CERTAIN GAS PRESSURE TO ANOTHER PLANT WITH A LOWER GAS PRESSURE | |
| WO2013126007A1 (en) | Arrangement, system and method for handling non-wood plant material | |
| WO1993023709A1 (en) | Apparatus for feeding a reactive component into a pressure vessel, for example a reactor chamber or a furnace | |
| US5213686A (en) | Compression feeder | |
| EP0009850B1 (en) | A device for compressing fibre material, in particular dried green fodder, into bales | |
| US3683796A (en) | Apparatus having an auger-compacter for reducing the volume of waste materials | |
| JPS6260517B2 (en) | ||
| GB1576154A (en) | Baler | |
| GB2131342A (en) | Method and apparatus for extrusion processing of cellulose or fibre containing materials | |
| US20090050000A1 (en) | Biomass pressure liquid recovery system | |
| US5471921A (en) | Apparatus for dewatering and lossening raw biopulp | |
| US4198302A (en) | Apparatus for relieving blockage of the pulp discharge passage in a cyclone in a pulping system | |
| AU642160B2 (en) | Improved plug screw feeder | |
| SE512732C2 (en) | Screw Press | |
| EP3666859A1 (en) | Speed controlled plug screw feeder | |
| AU7128187A (en) | Screw press | |
| CA1223578A (en) | Method and apparatus for extrusion processing of cellulose bearing materials | |
| EP0034560A2 (en) | Method and apparatus for efficiently producing cellulosic pulp by the thermo-mechanical pulping method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |