Kamyr, Inc.

Ahlstrom Machinery, Inc.

Other

Erwin D Funk

Kaj Henricson

Joseph R Phillips

Carl L Elmore

Stephen J Dunn

C Bertil Stromberg

Bruno S Marcoccia

Rolf C Ryham

Brian F Greenwood

J Wayne Chamblee

Michael I Sherman

Ole J Richter

Mark D Barrett

James R Prough

Oliver A Laakso

Ted M Poulin

Mahendra R Doshi

Todd A Salvato

Keith A Carlton

Scott M Clum

John Baldwin

Stephen J Dunne

Rudy Koteles

John Bolles

A system and method for feeding comminuted cellulosic fibrous material such as wood chips to the top of a treatment vessel such as a continuous digester provide enhanced simplicity, operability, and maintainability by eliminating the high pressure transfer device conventionally used in the prior art. Instead of a high pressure transfer device the steamed and slurried chips are pressurized using one or more slurry pumps located at least thirty feet below the top of the treatment vessel and for pressurizing the slurry to a pressure of at least about 10 bar gauge. A return line from the top of the digester may, but need not necessarily, be operatively connected to the one or more pumps and if connected to the pumps the pressure in the return line may be reduced utilizing a pressure reduction valve and/or a flash tank. During pressurized transferring of the slurry from the pumps to a treatment vessel (which may be as little about 10 feet or as much as about a half a mile away) treatment liquid is provided which contains at least some active pumping chemical including sodium hydroxide, sodium sulfide; polysulfide, anthraquinone or their equivalents or derivatives; surfactants, enzymes, or chelants; or combinations thereof. Pseudo-countercurrent circulation of treatment liquids may be provided between stations.

Method for feeding comminuted fibrous material

A system and method for feeding comminuted cellulosic fibrous material such as wood chips to the top of a treatment vessel such as a continuous digester provide enhanced simplicity, operability, and maintainability by eliminating the high pressure transfer device conventionally used in the prior art. Instead of a high pressure transfer device the steamed and slurried chips are pressurized using one or more slurry pumps located at least thirty feet below the top of the treatment vessel and for pressurizing the slurry to a pressure of at least about 10 bar gauge. A return line from the top of the digester may, but need not necessarily, be operatively connected to the one or more pumps and if connected to the pumps the pressure in the return line may be reduced utilizing a pressure reduction valve and/or a flash tank. Steam from the flash tank may be used in steaming the chips. Pressure relief prevention may be provided by isolation valves in the lines leading to and from the top of the treatment vessel controlled by a controller which is responsive to the pressure sensed in the slurry line leading to the top of the treatment vessel.

Method and system for feeding comminuted fibrous material

A method and apparatus supply ozone containing gas under superatmospheric pressure to an ozone delignification device. The speed of a water ring compressor is controlled so that it compresses as much ozone gas per unit time at desired superatmospheric pressure as the ozone delignification unit utilizes, with essentially no excess. The ozone containing gas is fed from the water ring compressor through a separator buffer tank which levels out pressure pulses and separates cooling water from compressed ozone gas prior to the gas entering the ozone delignification unit. The gas passes through a control valve controlled by a mass flowmeter which senses the amount of cellulose pulp fed to the ozone delignification unit. The speed control of the compressor may be provided by a differential pressure controller connected across the control valve.

Method of controlling pressurized ozone to a pulp delignification reactor

A slurry of recycled cellulose fibers is deinked by introducing the slurry into the first end of a vortex, sparging gas radially inwardly into the slurry to cause gas bubbles to attach to contaminants and ink particles to form an aerated slurry, discharging the aerated slurry from near the second end of the vortex into a separation vessel, effecting separation of a foam of ink laden gas bubbles from the cellulose fiber slurry in the separation vessel, and removing from the separation vessel the foam with associated ink and contaminants in a first stream, and de-inked cellulose fiber slurry in a second stream. The separation vessel is typically a foam separating vessel with separation effected by flotation, and by discharging the foam. The slurry is introduced into the flotation vessel below the liquid level in it. The slurry typically has a consistency of about 0.5-2%, and the gas to slurry volume ratio during sparging may be 0.1-1 to 1.0 (e.g. 0.2-0.7 to 1, or 0.3-0.4 to 1). The foam separating vessel may be cylindrical with a shower head at the top, and rejects therefrom directed to a rejects tank. Sparging takes place in a hydrocyclone with an outlet that may or may not be restricted; a rejects outlet may extend from a first end of the hydrocyclone to a rejects tank.

Gas sparged hydrocyclone with foam separating vessel

In a method of bleaching medium consistency pulp with ozone using a mixer, ozone containing gas and about 6-15% consistency pulp are fed to the mixer, and then discharged in a first, preferably vertical, path. The mixture of pulp and ozone moves in a first part of the vertical path a time period of about 1-5 seconds at a velocity of about 1-5 m/s so that the gas and pulp do not separate during movement in this first part, and the vast majority of the pulp brightening reaction between the ozone and pulp takes place. This is preferably accomplished by passing the mixture upwardly in a small diameter conduit having a height of about 3-20 meters. Then the velocity of the pulp is slowed while still moving in the first path, preferably by feeding it directly to a much larger diameter (e. g. 1.5-10 times) conduit, so the height of the unit may be kept under 100 feet. The pulp flows in the large diameter conduit for about 0.5-5 minutes so that residual reactions take place.

Medium consistency ozone bleaching

Medium consistency (e.g. about 6-15%) paper pulp is effectively bleached with ozone in a carrier gas (typically oxygen) by effecting efficient separation of carrier gas from the pulp after reaction with the ozone, and introducing the ozone into the pulp at a pressure of about 10-13 bar. Ozone in oxygen and medium consistency paper pulp are fed to a fluidizing mixer; the intimate uniform mixture produced is then passed upwardly in a reaction vessel until about 99% of the ozone has been consumed, and then separation of gas from the pulp is initiated by moving the pulp mixture into a generally horizontal tube leading to a gas zone in a large diameter retention vessel. A pressurized gas pad is maintained at and above the introduction of the pulp into the retention vessel, while the level of pulp in the retention vessel is maintained below the point of introduction. The pulp may be withdrawn from the retention vessel with a fluidizing degassing pump, and the pressurized gas removed from the top of the vessel may be fed to an apparatus using oxygen gas under pressure.

Medium consistency pulp ozone bleaching

Pressurized ozone pulp delignification reactor and a compressor for

Compressible material is compacted into a plug by a device including a housing, solid outer wall, and restricting adjustable portion at an outlet. A root wall is rotated about an axis and conveys the material to be compressed in a channel having solid sidewalls. Without significant extraction of liquid from the material, the material is compressed until discharged in a compacted plug form from the housing outlet. A pneumatic cylinder provides an adjustable force for effecting the compaction adjacent the housing outlet. Examples of compressible materials that may be acted upon in the practice of various industrial processes include wood chips, high consistency paper pulp (cellulose pulp), wax and fibrous waste (for making artificial fireplace logs), and mud and straw (for producing building blocks or bricks).

Compression feeder

In a dewatering press having a number of rotors rotatable in a cylindrical press housing with an inlet channel defining an inlet for a humid mass into the housing, a mechanism for equalizing the amount of mass fed to the inlet channels. A screw feeder is associated with each inlet channel, and equalization is accomplished by providing opening communication between the screw feeders at their pressure ends, adjacent the inlet channels. A module having a conduit associated with each inlet channel, and a cross over tunnel at the portion of the module adjacent the press housing, is disposed between the feeder screw housing and the press housing.

Feeding equalization for sludge presses

It is desirable to be able to treat medium consistency (e.g. about 8-12% by weight) paper pulp suspensions with treatment liquid (e.g. a wash liquid), and to thicken the pulp to about 30-50% consistency at the same time. A moving (e.g. rotating) channel is defined by a root wall and upstanding side walls--some or all of which are perforated--and treatment liquid is introduced by an arcuately elongated distributor with perforated side walls into the center of the pulp within the channel, filtrate flowing out through the perforated walls. A pivoted wall portion of the stationary housing of the treatment device restricts outflow of the thickened pulp cake from the device, the cake flowing between a doctor blade and the pivoted wall portion.

Method and apparatus for liquid treatment of and liquid extraction on a

A method and apparatus are provided for the dehydration of low rank coal, such as lignite. The coal is formed into particles having a size of less than about 4 inches, is subjected to atmospheric steaming, and then preheating with steam at a pressure of about 20-100 psig. The particles are then entrained in liquid and fed to a high pressure feeder at which they are transferred to a high pressure circulation loop, at a pressure of between about 300-1500 psig. The particles and liquid are fed to a liquid/particles separator at the top of a vertical dehydrating vessel, and the particles at the top of the vessel are contacted by saturated steam. Condensed steam and particles flow downwardly in the dehydration vessel, and are subjected to a counter-current wash at the bottom of the vessel. A slurry of liquid and particles discharged from the bottom of the dehydration vessel has the pressure thereof gradually reduced in a second high pressure feeder, and is transferred to a low pressure loop at a pressure of between about 20-100 psig. The liquid and particles are separated, and then the particles are subjected to evaporative cooling.

Dehydration of lignite or the like

A low pressure feeder includes a rotor containing at least one pocket having a single access opening to it, the rotor rotatable about an axis and enclosed in a housing having an inlet port vertically above an outlet port. A sealing structure is disposed in a large clearance volume between the rotor and the housing, the sealing structure comprising a single shoe having an opening communicating with the inlet port, and one or more pressure compensators for biasing the shoe into engagement with the rotor. The pressure compensators are responsive to the process pressure at the feeder high pressure outlet port. A gas blast structure is provided for supplying a blast of gas to the pocket to effect discharge of material from the pocket when it is in communication with the outlet port. A vent is provided immediately before the inlet port in the direction of rotation of the roller, the access opening being dimensioned with respect to the vent and inlet port so that it can communicate with both during a portion of path of rotation thereof.

Simple dry feeder

A method of transporting heavier than water particles such as coal from an elevated supply site to a delivery site at a substantial elevation below said elevated supply site comprising the steps of mixing the particles at the supply site with liquid such as water to form a slurry of particles and liquid, introducing slurry at the supply site into a confined path extending downwardly from the supply site to the delivery site, confining a volume of slurry material in energy transmitting relation to the slurry in the confined path such that the static head of the slurry in the confined path is transmitted to the confined volume, continuously withdrawing material from the confined volume at spaced first and second positions and introducing liquid into the confined volume in such a way as to (1) maintain the pressure conditions within the confined volume generally equal to the static head of the slurry in the confined path minus the friction losses and (2) enable slurry from the confined path to flow into the confined volume and the particles thereof to move within the confined volume such that the material at the first withdrawal position contains the larger particles of the slurry and the material at the second withdrawal position is substantially devoid of the larger particles of the slurry, continuously separating a liquid fraction from the material withdrawn from the confined volume at the second withdrawal position in such a way that the pressure of said liquid fraction is not materially lowered with respect to the pressure of the material in the confined volume, pumping the liquid fraction along a confined path extending upwardly to the supply site, and utilizing the liquid fraction pumped to the supply site as the liquid in the mixing step, and apparatus for carrying out the method.

Method and apparatus for transporting mined particles from an elevated

A method and system are provided for continuously conveying hard particulate material of non-uniform size, like coal. A high pressure transfer device has high and low pressure feed and discharge lines extending to and from it, and a screen arrangement for allowing liquid and fines to pass from the low pressure feed line to the low pressure discharge line, while stopping large particles. An excess accumulation of fines is prevented by providing a screen assembly vertically above the high pressure transfer device. Level control in a hopper--which provides the low pressure feed line--is accomplished merely utilizing an overflow technique. The concentration of particles in the liquid in the high pressure discharge line is maintained about 50% by withdrawing a portion of the liquid (while still under pressure) from the high pressure discharge line, and returning it to the high pressure feed line. A density measuring device downstream of the liquid withdrawal automatically controls the amount of liquid withdrawal.

Materials transfer system and methodology

A method of recovering mineral nodules deposited on the ocean floor which comprises the steps of pumping a continuous flow of ocean water along a first confined path through an exchange position within the vicinity of the ocean floor where the mineral nodules to be recovered are deposited from an ocean water inlet position out of the aforesaid ocean vicinity and then upwardly to a discharge position on a surface vessel, confining ocean water within a second path within the aforesaid ocean vicinity, continuously flowing ocean water in the second path by pumping the same at a pumping position spaced down-stream from an exchange position therein, continuously moving from the ocean floor to a separating position within the aforesaid ocean vicinity a mixture containing deposited mineral nodules and smaller particles forming a part of the ocean floor on which the mineral nodules were deposited, continuously separating the mixture at the separating position so as to obtain a supply of separated mineral nodules within ocean water, continuously feeding the supply of separated mineral nodules to the second path at a feeding position upstream from the exchange position therein, and continuously exchanging between the exchange positions within the first and second paths successive incremental volumes of ocean water and mineral nodules from the second path to the first path with comparable successive incremental volumes of ocean water from the first path to the second path.

Growing community of inventors

Glens Falls, NY, United States of America

Erwin D Funk