Champion International Corporation Limited

Henry A Fremont

Walter Phalti Lawrence

Edward F Hedrick

William C Dorman

James W Bray

Mary C Obenour

Richard C Agar

Gregory W Marquart

An apparatus and method for dewatering sludges and the like as part of landfill operations by electrokinetic techniques including placing anode and cathode electrode modules in contact with the sludge and applying electrical energy to the electrodes to establish an electric field in the sludge. Charged particles within the sludge, including macro-molecules, colloids, and suspended particles, electrophoretically migrate to the oppositely charged counter electrode and consolidate. A filtration media located at one of the electrodes permits the electro-osmotic removal of water from the sludge to encourage solids densification. The electrical energy applied to the electrodes is a chopped, time-varying, intermittent unidirectional current having a rapid rise edge which provides dewatering results comparable to prior methods that used direct current or full AC current but at substantially reduced energy consumption to provide more economical dewatering. Presently preferred optimum conditions for practicing the invention are also disclosed, including means for applying the techniques of the disclosure to a continuous dewatering method and an apparatus for practicing that method. The application of the electrokinetic techniques to other processes such as electrodialysis, including electrolysis (using a membrane or bipolar membrane), desalinization or metathesis; and electrowinning, including electroplating; and other electrophoretic processes is suggested.

Continuous dewatering method

A process for cleaning fouled separation membranes such as ultrafiltration, reverse osmosis, and microfiltration membranes is provided comprising: removing a separation membrane having a fouled surface from operation; effecting reaction on the fouled surface of said membrane of an inorganic peroxide and an alkali metal or alkaline earth metal hypohalite; and thereafter, substantially removing the foulant and the reaction products thereof from the membrane surface.

Membrane cleaning process

An apparatus and method for dewatering sludges and the like as part of landfill operations by electrokinetic techniques including placing anode and cathode electrode modules in contact with the sludge and applying electrical energy to the electrodes to establish an electric field in the sludge. Charged particles within the sludge, including macro-molecules, colloids, and suspended particles, elecrophoretically migrate to the oppositely charged counter electrode and consolidate. A filtration media located at one of the electrodes permits the electro-osmotic removal of water from the sludge to encourage solids densification. The electrical energy applied to the electrodes is a chopped, time-varying, intermittent unidirectional current having a rapid rise edge which provides dewatering results comparable to prior methods that used direct current or full AC current but at substantially reduced energy consumption to provide more economical dewatering. Presently preferred optimum conditions for practicing the invention are also disclosed, including means for applying the techniques of the disclosure to a continuous dewatering method and an apparatus for practicing that method.

Continuous dewatering apparatus

The present invention relates to a novel cellulosic wood pulp fiber having lower specific volume for a given surface area than conventionally prepared wood pulp fibers, to products made therefrom, and to the process of making such fiber comprising hydrating cellulosic wood pulp fiber to a freeness of at least about 650 CSF and lower, freezing the fibers while in an aqueous slurry containing at least 40% water to a fiber temperature of at least -5.degree. C. or below, and thawing the pulp fibers to a temperature at which they will flow.

Wood pulp fiber process and resultant products

A process of making polyethylene pellets from polyethylene broke comprising forming a polyethylene solvent-free aqueous slurry of said broke and defibering said slurry to produce a polyethylene slurry having a fiber to solid polyethylene ratio of no more 1:20, dehydrating said polyethylene slurry to less than about 15% water, and pelletizing the polyethylene.

Polyethylene recovery from broke

An apparatus and method for filtering and classifying waste or process streams into three product streams using a polymeric net belt to drive a filter drum and hydrophobic polymeric filter element thereon. A matte of solids is doctored from the belt to provide a first product stream. A roller mounted on a fluid cylinder driven pivoted arm compresses the filter element to provide a smaller suspended solids stream for collection in a trough inside the drum. This second product stream is removed axially from the trough by means of a pump. A third clarified or effluent stream is produced and collected in the drum as the stream passes through the foam filter element. This third stream is removed axially in the direction opposite of said second stream. A shower keeps the foam in the compressed area water filled to prevent vapor lock or gas blockage in the cellular foam filter.

Apparatus and method for removing suspended solids from a stream

Disclosed is a process for extraction of coniferous woods, such as pine, with supercritical fluids to recover tall oil and turpentine, or components thereof. Gases such as carbon dioxide, nitrous oxide, nitrogen, and lower alkanes or lower alkenes at temperatures above critical and pressures of about 100 psi above critical; i.e., supercritical fluids, are contacted with subdivided wood. The extracted wood is suitable for pulping and subsequent papermaking. The extract-bearing fluid is preferably stripped of the extracts by reducing the pressure in stages, each pressure reduction effecting removal of extracts of a narrowly-defined molecular weight range. The fluid is recompressed and recycled.

Extraction of coniferous woods with fluid carbon dioxide and other

The method of removing fine suspended solids from an effluent stream comprising passing said stream through at least two contiguous layers of an open-celled compressible hydrophobic polymeric material and compressing said layers to remove the solids loaded therein to regenerate said material, said material being layered so that the open cells of each layer are randomly oriented.

Method of removing fine suspended solids from effluent streams

The method of treating an activated sludge to facilitate dewatering thereof comprising the steps of acidifying the sludge to a pH below about 2.2, heating the acidified sludge to a temperature of from about 150.degree. to 210.degree. F. and maintaining the sludge at said temperature for a period of time sufficient to obtain a settling rate of solids in the first three minutes of at least two-sixteenths inch per minute.

Activated sludge treatment

An improved method for removal of color bodies from aqueous effluents from paper and pulp mill manufacturing operations by ultrafiltration wherein the semi-permeable membrane utilized is a polyethyleneimine coated polysulfone film.

Color removal from paper and pulp mill aqueous effluents

An emission control system and a method of treating a gaseous effluent is disclosed. The system is particularly suited for treating gaseous effluents from a veneer dryer prior to venting to the atmosphere. The system comprises means for temperature adjustment, flow control, and catalytic oxidation of the effluent.

Emission control system and method

Black liquor obtained from the sulfate pulping of resinous woods, such as that obtained from sulfate pulp digestors, is flowed into a skim tank where tall oil soap is skimmed from the surface. The skimmed effluent black liquor from the skim tank is passed through an ultrafiltration unit. Residual tall oil soap content in the black liquor effluent is concentrated in this unit and then recycled to the skim tank, while the permeate is sent to disposal. A by-pass is provided around the ultrafiltration unit to prevent build up of insoluble material such as fiber and other debris in the skim tank. The continued concentration of the tall oil soap in the skim tank causes the tall oil soap to agglomerate thereby decreasing its solubility in the black liquor, and allowing additional tall oil soap to be recovered. Improved yields of tall oil soap at lower costs and use of energy result. Tall oil is then produced by acidifying the recovered tall oil soap skimmings.

Process for enhancing recovery of tall oil soap from black liquor

An emission control system and a method of treating a gaseous effluent from a veneer dryer prior to venting to the atmosphere. The system comprises means for temperature adjustment, flow control, and catalytic oxidation of the effluent.

Emission control system

This invention relates to an improved process and apparatus system for the continuous production of thin fiberboard products wherein a binder-impregnated wood fiber mat is continuously formed and then continuously and successively passed through a conditioning zone where the mat temperature is adjusted to about the glass transition temperature of the ligneous hemicellulosic matrix material of the wood fiber at a moisture content from about 6% to 12% by weight, prepressed to reduce the bulk thereof and substantially eliminate entrained air therefrom, hot pressed at a temperature and for a time sufficient to reduce the mat to the final thickness desired and to initiate but not to complete cure of the binder, and thereafter subjected to a temperature sufficient, but not above about 350.degree. F., and for a time sufficient to complete binder cure and mat consolidation.

Fiberboard manufacture

The method of treating a chlorine-based total bleachery effluent in which only a chlorine and sodium salts are used in the bleach sequence comprising the steps of adding aluminum ion to said effluent in an amount sufficient to precipitate substantially all of the organics and suspended solids therein, separating the solids from said effluent, electrodialyzing the treated effluent to provide two effluent streams, one containing 200 to 600 parts per million sodium chloride which can be returned to the bleachery, and a second concentrated stream containing 5 to 10% by weight sodium chloride, evaporating said concentrated stream to a concentration of about 25% sodium chloride by weight, and electrolyzing said concentrated sodium chloride solution to produce chlorine gas, sodium hydroxide, and sodium hypochlorite.

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Wyoming, OH, United States of America

Henry A Fremont