Liquid removal apparatus and method for wood pulp

A method to accomplish liquid removal from a pulp slurry, said method comprising:

• a. moving the slurry into an above atmospheric pressure chamber in a manner to form said slurry as a layer at a processing area over a foraminous support surface means of a table assembly positioned in said pressure chamber;
• b. creating a lower pressure level, relative to the pressure level in said pressure chamber, in a pressure differential chamber provided in said table assembly, with said pressure differential chamber extending beneath said processing area, to create a pressure differential with said layer being stationary at said processing area to cause said liquid removal from said layer;
• c. creating a higher pressure level in said pressure differential chamber relative to the pressure level in said pressure chamber subsequent to said liquid removal to reduce said pressure differential;
• d. removing said layer from said processing area and from said pressure chamber, while maintaining above atmospheric pressure in said pressure chamber.

An apparatus for removing liquid from pulp slurry comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the pulp slurry thereon, said table assembly being arranged to contain said pulp slurry in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of pulp slurry under pressure into said chamber and onto said surface as a layer, with said layer in said processing area being at a stationary location relative to said support surface;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said pulp slurry on said surface means to cause liquid to flow from said pulp slurry to said pressure differential chamber, and also to reduce said pressure differential;
• g. removal means to remove said pulp slurry after liquid removal therefrom and after said pressure differential is reduced;
• h. said table assembly, including the pressure differential chamber, being positioned entirely in said pressure chamber.

An apparatus for removing liquid from pulp slurry comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the pulp slurry thereon, said table assembly being arranged to contain said pulp slurry in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of pulp slurry under pressure into said chamber and onto said surface as a layer, with said layer in said processing area being at a stationary location relative to said support surface;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said pulp slurry on said surface means to cause liquid to flow from said pulp slurry to said pressure differential chamber, and also to reduce said pressure differential;
• g. removal means to remove said pulp slurry after liquid removal therefrom and after said pressure differential is reduced;
• h. a contact plate means which is located in said pressure chamber and is moveable from an upper position above said processing area downwardly to a contact position where the contact plate means passes against said pulp slurry to enhance liquid removal.

An apparatus for removing liquid from pulp slurry comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the pulp slurry thereon, said table assembly being arranged to contain said pulp slurry in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of pulp slurry under pressure into said chamber and onto said surface as a layer, with said layer in said processing area being at a stationary location relative to said support surface;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said pulp slurry on said surface means to cause liquid to flow from said pulp slurry to said pressure differential chamber to form a deliquified pulp layer, and also to reduce said pressure differential;
• g. removal means to remove said pulp slurry after liquid removal therefrom and after said pressure differential is reduced;
• h. said removal comprising conveying belt means, and a layer discharge means to remove said layer from said processing area, said layer discharge means comprising a passageway having an inlet to receive said layer from said conveying belt means, said discharge passageway being sized and configured to receive said layer in substantial sealing relationship in said passageway, and leading to a lower pressure location outside of said pressure chamber, said discharge means further comprising control outlet discharge valve means through which said layer is discharged from said lower pressure location.

An apparatus for removing liquid from pulp slurry comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the pulp slurry thereon, and said table assembly is arranged to contain said pulp slurry in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of pulp slurry under pressure into said chamber and onto said surface as a layer, with said layer in said processing area being at a stationary location relative to said support surface;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said pulp slurry on said surface means to cause liquid to flow from said pulp slurry to said pressure differential chamber, and also to reduce said pressure differential;
• g. said processing area being arranged to accomplish both dewatering and washing, and there is additionally washing liquid input means which delivers said washing liquid onto the layer at said processing area;
• and
• h. said pressure differential means comprising tube means connecting to said pressure differential chamber, equalizing valve means arranged to selectively interconnect said pressure differential chamber with said pressure chamber, pressure reduction valve means connecting said tube means to a lower pressure area to create a lower pressure level in said pressure differential chamber, at least one tube of said tube means being directed to a liquid collecting location, and a recirculating line directing liquid as recirculated liquid from said liquid collecting location back to said pressure vessel where said recirculated liquid can be used as a wash liquid for said layer;
• i. removal means to remove said pulp slurry after liquid removal therefrom and after said pressure differential is reduced.

An apparatus adapted to perform a liquid displacement operation either to remove liquid from a material or to move a liquid into said material, said apparatus comprising:

• a. a conveying structure comprising a perforate conveying means having a first high pressure side on which to receive a portion of said material and a second low pressure side, and a conveying support structure for said conveying means;
• b. supply means to supply said material to said conveying structure;
• c. frame enclosure means mounted relative to said conveying means for movement relative to said conveying means between a first engaged position with said conveying means and a second non-engaged position spaced from said conveying means, said frame enclosure means having perimeter wall means defining, in said first position, a containment processing area for said portion of material;
• d. pressure differential means to provide a first greater pressure differential between the high and low pressure sides of the conveying means to effect a displacement of liquid relative to said portion of material at said processing area by causing said liquid to move relative to said portion of material in a direction toward the low pressure side of said conveying means, and to provide a second lesser pressure differential between said high and low pressure sides of the conveying means at the processing area so as to relieve a pressure differential force against said conveying means;
• e. a frame actuating means to cause relative movement between said frame enclosure means and said conveying structure in a manner that with said frame enclosure means being moved to its second position relative to said conveying structure, said conveying means is able to move said portion of material from said processing area;
• f. a pressure vessel in which said conveying structure and said frame enclosure means are contained, said pressure vessel being structured and arranged to be pressurized to a pressure to apply pressure to the high pressure side of the conveying means.

A method to perform a liquid displacement operation either to remove liquid from a material or to move a fluid into said material, said method comprising:

• a. providing a conveying structure comprising a perforate conveying means having a first high pressure side and a second low pressure side, and supporting said conveying means by a conveying support structure, said conveying means being enclosed in a pressure vessel;
• b. pressurizing said pressure vessel;
• c. positioning frame enclosure means that is located in said pressure vessel at a first engaged position with said conveying means with said frame enclosure means having perimeter wall means defining, in said first position, a processing area, and depositing a portion of said material on the high pressure side of said conveying means in said processing area;
• d. applying a pressure differential between the high and low pressure sides of the conveying means to effect a displacement relative to said portion of material at said processing area by causing said liquid to move relative to said portion of material in a direction toward the low pressure side of said conveying means;
• e. then reducing said pressure differential between said high and low pressure sides of the conveying means at the processing area so as to relieve a pressure differential force against said conveying means;
• f. moving said frame enclosure means relative to said conveying structure in a manner that with said frame enclosure means moved to a second position relative to said conveying structure, so as to be spaced from said conveying means, said conveying means moves said portion of material from said processing area.

An apparatus for performing liquid removal from a liquid bearing material comprising:

• a. a pressure vessel having a processing area;
• b. means for delivering a portion of said material into said vessel to said processing area for liquid removal;
• c. means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom;
• d. means for discharging such removed liquid from said vessel;
• e. means to selectively reduce said pressure differential at said processing area;
• f. means for moving said portion of material from said processing area when said pressure differential has been reduced;
• g. means for removing said portion of material from said vessel after being moved from said processing area;
• h. said apparatus further comprising containment means positioned within said vessel to contain said material in said processing area, said containment means comprising an enclosure frame means extending around said processing area to contain said pulp slurry in said processing area, and at least a section of said enclosure frame means is moveable between a first position enclosing said processing area, and a second position where at least said section of said enclosure frame means is spaced from said processing area, said apparatus further comprising a frame actuating means to move at least said frame section between said first and second position.

An apparatus for performing liquid removal from a liquid bearing material comprising:

• a. a pressure vessel having a processing area;
• b. means for delivering a portion of said material into said vessel to said processing area for liquid removal;
• c. means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom;
• d. means for discharging such removed liquid from said vessel;
• e. means to selectively reduce said pressure differential at said processing area;
• f. means for moving said portion of material from said processing area when said pressure differential has been reduced;
• g. means for removing said portion of material from said vessel after being moved from said processing area;
• h. said apparatus having two processing area portions in said pressure vessel, namely a first dewatering area and a second washing area, said apparatus further comprising frame enclosure means comprising a first mat forming enclosure section and a second washing enclosure section, said mat forming enclosure section defining said dewatering area, and said second enclosure section defining said washing area;
• i. said apparatus also comprising a wash liquid supply means.

An apparatus for removing liquid from a material or to move a liquid into said material, said apparatus comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a chamber pressure level;
• c. a table assembly which is positioned entirely within said vessel has a perforate support surface means for receiving the material thereon, said table assembly being arranged to contain said material in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of said material under pressure into said chamber and onto said surface means;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said material on said surface means, and also to reduce said pressure differential;
• g. removal means to remove said material from said processing area after said pressure differential is reduced, and out of said pressure chamber;
• h. said pressure chamber extending both above and below said table assembly, and being arranged to remain pressurized when said material is removed from the pressure chamber.

An apparatus for removing liquid from a material or to move a liquid into said material, said apparatus comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a chamber pressure level;
• c. a table assembly which is positioned within said vessel, has a perforate support surface means for receiving the material thereon, and said table assembly is arranged to contain said material in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of said material under pressure into said chamber and onto said surface means;
• e. said table assembly defining a pressure differential chamber below said support surface;
• f. pressure differential means to create a pressure differential between said pressure differential chamber and said pressure chamber with said material on said surface means, and also to reduce said pressure differential;
• g. removal means to remove said material after said pressure differential is reduced;
• h. said apparatus further comprising containment means to contain said material in said processing area, said containment means comprising an enclosure frame means extending around said processing area to contain said material in said processing area, and at least a section of said enclosure frame means is moveable between a first position adjacent to said perforate support surface means so as to contain said material, and a second position where at least said section of said enclosure frame means is spaced from said support surface means, said assembly further comprising a frame actuating means to move at least said frame section between said first and second position.

An apparatus for removing liquid from a liquid bearing material, comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the liquid bearing material thereon in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of said liquid bearing material under pressure into said chamber and onto said support surface means as a layer;
• e. pressure differential means to create a pressure differential across said material on said support surface means to cause liquid to flow from said material;
• f. a contact plate means which is located in said pressure chamber and is moveable from an upper position above said processing area downwardly to a contact position where the contact plate means presses against said liquid bearing material to enhance liquid removal.

An apparatus for removing liquid from a liquid bearing material, comprising:

• a. a pressure vessel defining a pressure chamber;
• b. means to pressurize said pressure chamber to a pressure level above atmospheric pressure;
• c. a table assembly which has a perforate support surface means for receiving the liquid bearing material thereon, in a processing area that is located over the support surface means, said support surface means being exposed to pressure in said pressure chamber;
• d. infeed means to direct a portion of said liquid bearing material under pressure into said chamber and onto said surface as a layer;
• e. pressure differential means to create a pressure differential across said material on said surface means to cause liquid to flow from said pulp slurry;
• g. removal means to remove said pulp slurry after liquid removal therefrom while said pressure chamber is pressurized to a level above atmospheric pressure, said removal means comprising a conveying means and means defining a discharge passageway having an inlet to receive said material from said conveying means, said discharge passageway being sized and configured to receive said layer in substantial sealing relationship in said passageway, and leading to a lower pressure location outside of said pressure chamber, said removal means further comprising control outlet discharge valve means through which said material is discharged from said lower pressure location.

An apparatus for performing liquid removal from a liquid bearing material and subsequent liquid displacement through said material, said apparatus comprising:

• a. a pressure vessel having a processing area;
• b. means for delivering a portion of said material into said vessel to said processing area for liquid removal;
• c. means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom and form a deliquified layer of material;
• d. means for discharging such removed liquid from said vessel;
• e. means for delivering a portion of a displacement liquid into said vessel and onto said deliquified material, with said means to provide a pressure differential causing said displacement liquid to move into said layer of material and displace liquid therefrom;
• f. means to selectively reduce said pressure differential at said processing area;
• g. means for moving said portion of material from said processing area when said pressure differential has been reduced;
• h. means for removing said portion of material from said vessel after being moved from said processing area;
• i. said apparatus being structured and arranged so that said vessel is pressurized above atmospheric pressure when said portion of material is delivered into said vessel, when said pressure differential exists, when said displacement liquid is delivered into said vessel, when said pressure differential is reduced, and when said portion of material is removed from said vessel after removal of liquid and displacement of liquid.

A method to accomplish liquid removal from a liquid bearing material and liquid displacement in said material, said method comprising:

• a. moving the material into an above atmospheric pressure chamber in a manner to form said slurry as a layer at a processing area over a foraminous support surface means of a table assembly positioned in said pressure chamber;
• b. creating a lower pressure level, relative to the pressure level in said pressure chamber, in a pressure differential chamber provided in said table assembly, with said pressure differential chamber extending beneath said processing area, to create a pressure differential with said layer being stationary at said processing area to cause said liquid removal from said layer;
• c. introducing a portion of displacement liquid into said pressure chamber while maintaining above atmospheric pressure in said pressure chamber, with said pressure differential causing said displacement liquid to move into said layer to displace liquid then in said layer;
• d. creating a higher pressure level in said pressure differential chamber relative to the pressure level in said pressure chamber to reduce said pressure differential;
• e. removing said material from said chamber, while maintaining above atmospheric pressure in said chamber.

An apparatus for performing liquid removal from a liquid bearing material comprising:

• a pressure vessel having a processing area;
• means for pressurizing said vessel above atmospheric pressure;
• means for delivering a portion of said material into said vessel to said processing area for liquid removal, while said vessel is above atmospheric pressure;
• means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom, while maintaining said vessel pressurized above atmospheric pressure;
• means for discharging such removed liquid from said vessel while maintaining said vessel pressurized above atmospheric pressure;
• means to selectively reduce said pressure differential at said processing area while maintaining said vessel pressurized above atmospheric pressure;
• means for moving said portion of material from said processing area to another location in said vessel when said pressure differential has been reduced, and while maintaining said vessel above atmospheric pressure;
• means for removing said portion of material from said vessel after being moved to said another location, while maintaining said vessel above atmospheric pressure;
• said means to selectively provide a pressure differential comprising a table assembly positioned entirely with said pressure vessel and defining a pressure differential chamber in said table assembly;
• said means to selectively .provide said pressure differential further comprising means to open said pressure differential chamber to a pressurized chamber in said pressure vessel, and said means to reduce said pressure differential comprises means to open said pressure differential chamber to a lower pressure area outside of said pressure vessel.

A method for performing liquid removal from a liquid bearing material comprising:

• delivering a portion of said material into a pressure chamber to a processing area therein while said chamber is pressurized above atmospheric pressure;
• providing a pressure differential across said portion at said processing area to remove liquid therefrom while maintaining said chamber pressurized above atmospheric pressure;
• discharging such removed liquid from said chamber while maintaining said vessel pressurized above atmospheric pressure;
• reducing said pressure differential at said processing area while maintaining said chamber above atmospheric pressure;
• moving said portion from said processing area, when said pressure differential has been reduced, to a location outside of said chamber, while maintaining said chamber above atmospheric pressure;
• said pressure differential being provided by creating a lower pressure level, relative to the pressure level in said pressure chamber, in a pressure differential chamber provided in a table assembly positioned in said pressure chamber, while maintaining pressure in said pressure chamber above atmospheric pressure and said pressure differential being reduced by creating a higher pressure level above atmospheric pressure in said pressure differential chamber relative to the pressure level in said pressure chamber, while maintaining pressure in said pressure chamber above atmospheric pressure.

An apparatus for performing liquid removal from a liquid bearing material comprising:

• a pressure vessel having a processing area;
• means for pressurizing said vessel above atmospheric pressure;
• means for delivering a portion of said material into said vessel to said processing area for liquid removal, while said vessel is above atmospheric pressure;
• means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom, while maintaining said vessel pressurized above atmospheric pressure
• means for discharging such removed liquid from said vessel while maintaining said vessel pressurized above atmospheric pressure;
• means to selectively reduce said pressure differential at said processing area while maintaining said vessel pressurized above atmospheric pressure;
• means for moving said portion of material from said processing area to another location in said vessel when said pressure differential has been reduced, and while maintaining said vessel above atmospheric pressure;
• means for removing said portion of material from said vessel after being to said another location, while maintaining said vessel above atmospheric pressure;
• contact plate means which is located in said pressure chamber and is moveable from an upper position above said processing area downwardly to a contact position where the contact plate means presses against said pulp slurry to enhance liquid removal.

An apparatus for performing liquid removal from a liquid bearing material comprising:

• a pressure vessel having a processing area;
• means for pressurizing said vessel above atmospheric pressure;
• means for delivering a portion of said material into said vessel to said processing area for liquid removal, while said vessel is above atmospheric pressure;
• means to selectively provide a pressure differential across said portion at said processing area to remove liquid therefrom, while maintaining said vessel pressurized above atmospheric pressure;
• means for discharging such removed liquid from said vessel while maintaining said vessel pressurized above atmospheric pressure;
• means to selectively reduce said pressure differential at said processing area while maintaining said vessel pressurized above atmospheric pressure;
• means for moving said portion of material from said processing area to another location in said vessel when said pressure differential has been reduced, and while maintaining said vessel above atmospheric pressure;
• means for removing said portion of material from said vessel after being moved to said another location, while maintaining said vessel above atmospheric pressure;
• said means for removing said portion of material from said vessel comprising means defining a passageway having an inlet to receive said material, said passageway being sized and converted to receive said material in substantial sealing relationship in said passageway, and leading to a lower pressure location outside of said pressure vessel, control outlet discharge valve means through which said material is discharged outside said vessel.