Abstract: An electrofiltering process for dewatering or separating particles from a liquid or a colloidal suspension, which comprises the use of an electrofilter with separated, submerged electrodes, consisting of a cathode assembly and an anode assembly, wherein the filtrate is recirculated from the cathode assembly of the electrofilter into the anode assembly where it is utilized as anolyte. An initial electrolytic solution containing a soluble compound of an alkali or alkaline earth metal, such as NaOH or NaHCO.sub.3, is added to the anode assembly as anolyte. A direct current is applied to the electrofilter, so that negatively charged particles in the suspension will migrate towards the anode assembly and form a caked deposit or slurry layer on the outside of the assembly. Simultaneouslly, the electrode reactions at the cathode will split water into hydrogen gas and hydroxide. This hydroxide is diluted with filtrate passing into the cathode assembly.

Abstract: A method and apparatus for measuring a colloidal potential are described using pulses of ultrasonic energy that are directed along a path within a liquid suspension of colloidal particles. A vibration potential is measured at at least a pair of positions along the path. The positions are known relative to the source of ultrasonic pulses. The vibration potential measurements are then used to derive a colloidal potential which is independent of its attenuation encountered by the ultrasonic energy inside the suspension. In one embodiment several potential measuring probes are used and in another embodiment one probe is moved between predetermined positions.

Abstract: An electrically augmented vacuum filtration apparatus and process wherein a suspension of solids is dewatered in a bath located between electrodes of opposite polarity with intermediate biodes (a biode being in a sense a combined anode and cathode structure) positioned in the bath between the electrodes.

Abstract: An electrode assembly for use in dewatering a suspension of solids in which an electric field augments an applied vacuum includes a chamber having ion-pervious walls on which a cake of solids is deposited and an electrode element within the chamber immersed in an electrolyte; the surface area of the ion-pervious walls being substantially greater than the surface area of the electrode element.

Abstract: A process for dewatering a suspension of solids in an electric field controllably maintained between opposing electrode structures, causing the solids to migrate relative to the carrier liquid to form a layer or cake on one set of electrode structures while withdrawing carrier liquid under vacuum in the opposite direction through the liqid pervious wall of hollow, counterelectrode structures. A selected electrolyte is pumped through the hollow electrode structure on which the cake is formed to continuously bathe the electrode element therein in said electrolyte. Vacuum is applied to the electrolyte in said electrode structure to remove gases evolved at the electrode element. The cake material is detached from the electrode structure and recovered.

Abstract: A system and method for dewatering of a suspension of solids in an electric field controllably maintained between a pair of opposing self-contained electrode structures, to cause the solids to migrate relative to the carrier liquid to form a layer or cake on the respective self-contained electrode structure, while allowing carrier liquid to be withdrawn under vacuum in the opposite direction through the liquid-pervious wall of a hollow self-contained counter electrode structure, combined with means for controlling the rate of filtrate liquid withdrawal consistent and compatible with the relative speed of migration of the solids in the carrier liquid, and wherein said layer or cake material may be detached from said electrode structure, for instance during exposure from the suspension.

Abstract: A system for dewatering a suspension of solids in an electric field controllably maintained between opposing electrode structures, to cause the solids to migrate relative to the carrier liquid to form a layer or cake on one set of electrode structures in which the electrode members are positioned within ion-permeable walls and immersed in a selected electrolyte, while allowing carrier liquid to be withdrawn under vacuum in the opposite direction through the liquid-pervious wall of hollow, counter electrode structures, and wherein said layer or cake material may be detached from said electrode structures during exposure from the suspension.

Abstract: A system and method for dewatering of a suspension of solids in an electric field controllably maintained between a pair of opposing self-contained electrode structures, to cause the solids to migrate relative to the carrier liquid to form a layer or cake on the respective self-contained electrode structure, while allowing carrier liquid to be withdrawn under vacuum in the opposite direction through the liquid - pervious wall of a hollow self-contained counter electrode structure, combined with means for controlling the rate of filtrate liquid withdrawal consistent and compatible with the relative speed of migration of the solids in the carrier liquid, and wherein said layer or cake material may be detached from said electrode structure, for instance during exposure from the suspension.