Abstract: The present invention is directed to a dewatering aid which functions unexpectedly efficiently in the dewatering of a particulate solids slurry, e.g. mineral ore concentrate or slurry, wherein a dewatering aid is added thereto followed by filtration of the slurry. Such improved dewatering results are achieved by adding to the mineral ore slurry, an effective amount of a dewatering aid comprising an alkoxylated C.sub.6 -C.sub.11 alkanol or alkanoic acid wherein alkoxylation is conducted with propylene oxide or butylene oxide.

Abstract: Aqueous mineral slurries are treated prior to dewatering, to increase throughput, with a condensation product of formaldehyde and dicyandiamide, which may be further reacted with ammonia or an ammonia salt and an alkylenepolyamine or copper chloride.

Abstract: Finely divided aqueous mineral slurries such as kaolin clay and calcium carbonate are dewatered, filtered and prepared for shipment by and with the addition of an effective amount (preferably 0.01 to 4.0 pounds per ton of solids) of melamine/formaldehyde polymer.

Abstract: A twin belt filter press system has an amendment such as sawdust, fed to a sludge or slurry being dewatered after the sludge/slurry has been initially dewatered in a gravity drain section to form a cake on a first porous belt. The amendment cascades into the partially dewatered cake off the first belt, allowing mixing of the cake and amendment in an essentially belt-wide drop zone so that the amendment partially and quickly desorbs the cake before the cake and amendment mixture progresses into a nip formed by the first belt and a porous second belt. The mixture subsequently is carried in a position between the belts for pressing to remove moisture from both the cake and amendment. In one embodiment a shear-minimizing mixer is arranged in the amendment drop zone to additionally mix the amendment with the cake.

Abstract: A process for separating water and hydrocarbon from the solids in a petroleum product tank sludge is water-free, solvent-free, conducted at ambient conditions, utilizes no pre-coating with a filter aid, and creates no hazardous environment for filtering finished product sludge, such as gasoline. The process comprises operating a first pump and pumping sludge to a mixing tank and agitating the mixture. Solids content is measured and a determined volume of filter aid is added. The filter aid and sludge are mixed by operation of a mixer assembly which co-acts with baffles in the tank to achieve homogeneity in the mixing tank. A second pump pumps the mixing sludge and filter aid through one of a plurality of alternately selectable sealed horizontal plate filter and recirculates the filtered liquid back through the mixing tank until a desired clarity is reached.

Abstract: A fluid filter is disclosed which includes a casing defining a fluid chamber with inlet and outlet apertures to and from the chamber to respectively conduct unfiltered fluid to the chamber and filtered fluid from the chamber. A flow path is defined within the chamber and a filter is interposed in the flow path substantially normal to the direction of flow of the fluid in the chamber. The filter includes a screen having a covering of a filter aid, such as diatomaceous earth, on an upstream side of the screen. The filter is regenerated by reciprocating the screen relative to the casing in a path corresponding to the path defined by the direction of flow.

Abstract: An apparatus and process of filtering fluids, such as white water is provided for use in the place of an existing save-all device or downstream of an existing save-all device at a paper-making mill. The white water having contaminants in a suspended state is introduced into the filtration vessel and is withdrawn from the interior of the filter element positioned within the filtration vessel. To clean the filter element from the cake which has built up on the exterior surface of the filter element, a backflushing shock is applied to the interior of the filter element, forcing all cake settled on the exterior to be dislodged, thereby cleaning the filter element. The backflushing shock is delivered from a backflushing reservoir wherein the backflushing fluid is contained under pressure at a level at least slightly above the level of a pressure differential which has built up across the filter element. The shock is applied for a period of 1-2 seconds, during which time the backflush reservoir is emptied.

Abstract: Water can be removed from an aqueous clay slurry using techniques such as filtration wherein the slurry is contacted with an anionic polymer having a molecular weight in the range from about 3,000 to about 1,000,000. The water is removed from the slurry at a rapid rate in order to provide a clay cake.

Abstract: A composition for promoting dewatering of granulated slag which comprises the combination of an anionic polyether sulfate surfactant with a cationic nitrogen-containing surfactant and optionally a defoaming agent, and a process for promoting dewatering of granulated slag using such composition, which are useful for preparing granulated slag having a moisture content of 4% or less as a material for cement.

Abstract: Disclosed is a method for dewatering an aqueous slurry of solid coal particulates wherein a dewatering aid is added to the slurry followed by filtration thereof, preferably with vacuum augmentation. Selected quaternary ammonium dewatering aids of specific structure are disclosed.

Abstract: An apparatus and process of filtering fluids, such as white water is provided for use in the place of an existing save-all device or downstream of an existing save-all device at a paper-making mill. The white water having contaminants in a suspended state is introduced into the filtration vessel and is withdrawn from the interior of the filter element positioned within the filtration vessel. To clean the filter element from the cake which has built up on the exterior surface of the filter element, a backflushing shock is applied to the interior of the filter element, forcing all cake settled on the exterior to be dislodged, thereby cleaning the filter element. The backflushing shock is delivered from a backflushing reservoir wherein the backflushing fluid is contained under pressure at a level at least slightly above the level of a pressure differential which has built up across the filter element. The shock is applied for a period of 1-2 seconds, during which time the backflush reservoir is emptied.

Abstract: This disclosure concerns a composition and process for separating solids from an oil and water mixture. The composition comprises lime and calcined perlite of a size distribution such than 0-5% is retained on 30 mesh, 45-65% is retained on 50 mesh, 80-90% is retained on 100 mesh and 90-100% is retained on 200 mesh screens. The process is particularly applicable to separating solids from an oily sludge to produce a recoverable oil product and a non-leaching filter cake which is environmentally acceptable.

Abstract: Separation of gypsum from phosphoric acid liquor produced during the production of phosphoric acid from finely ground phosphate rock. These aids are characterized as containing sulfonate and acrylamide.

Abstract: The invention relates to a process for improving the sedimentation and filtering properties of waste waters and/or slurries and muds containing clay minerals. The waste waters and/or slurries obtained in the various technologies and containing clay minerals and optionally also other solid components are treated with compounds containing ions having a hydrated ionic diameter of from 0.12 to 0.15 nm and a co-ordination number of 12.

Abstract: A method and apparatus for filtering/concentrating a raw liquid such as industrial waste water or suspension of various kinds. Such raw liquid is additionally dispersed with grains in advance before being subjected to a cross flow filtration in which a tubular filtering member is used. The raw liquid is supplied through the tubular member under pressure. Since the tubular filtering member is provided with a guide member which guides the supplied raw liquid spirally therealong, suspended matter or suspended particles will not stay on the filtering surface. The size of the grains is less than one third the diameter of the tubular member in case where said grains have a specific gravity larger than the raw liquid. If the grains have a specific gravity smaller than the raw liquid, the grain size may vary from one tenth to nine tenths the tubular filtering member.

Abstract: This invention relates to products obtained from sugar mill boiler ash, methods of using such products as a filtration material, and/or adsorbent material and methods of manufacturing such products. More specifically, this invention relates to filtration materials, with either a low or relatively high activated carbon content derived from the combustion of sugar cane residues whose characteristics and properties can be preselected and controlled to provide predetermined performance characteristics, and methods of obtaining such products through processing techniques which control the properties of such products. The invention also provides adsorbent materials of very high carbon content useful for applications other than a filter medium.

Abstract: A process is disclosed for treating sludge to remove the liquid hydrocarbons from the insoluble particles in the sludge to provide treated particles which are environmentally safe. The process involves mixing the sludge with a hydrocarbon diluent, separating the particles from the diluent-sludge mixture, then mixing the separated particles and remaining diluent with water and distilling off the remaining diluent to obtain the treated particles.

Abstract: An improved process for the preparation of TiCl.sub.4 comprising(a) chlorinating a raw material containing titanium and vanadium impurities to produce a crude TiCl.sub.4 reaction product,(b) separating the crude reaction product into solid by-products and TiCl.sub.4 -containing liquid,(c) reacting the TiCl.sub.4 -containing liquid with a reducing agent whereby vanadium impurities are converted into solid compounds, and(d) separating TiCl.sub.4 from the solid vanadium compounds, is improved by adding solid products of the vanadium reduction reactions to the crude TiCl.sub.4 reaction product prior to the separating step (b).

Abstract: Apparatus is provided to allow a relatively high pressure differential to build up across the filter element and layer of filter media in a filter aid filtration vessel.A process and apparatus are provided for reusing filter media in a filter aid filtration system.A process and apparatus are provided for drying filter cake in a filtration vessel to facilitate its disposal. Pressurized gas is used to assist in blowing the filter cake off of the filter elements.A process and apparatus are provided for draining the heel of a filter aid filtration vessel as filtrate.

Abstract: Process and apparatus for ultrafiltration of the cooling water of a pressurized water nuclear reactor, during operation of the reactor. A fraction of the flow of pressurized water is withdrawn continuously in at least one cold branch (8) of the primary circuit (2). This withdrawn water is circulated, while it is still at the temperature and pressure of the primary circuit (2), in contact with the entry face of an ultrafiltration wall (40). The filtrate is withdrawn at a pressure which is less than 15 bars lower than the primary water pressure. The concentrate is kept in circulation with the entry face of the wall (40). The wall (40) can consist of an assembly of tubes maintained between two tube plates. The invention applies to pressurized water nuclear reactors whatever the number of primary circuit loops.

Abstract: An apparatus for effecting filtration, clarification and purification of liquid which comprises a housing containing a filter element made up of a plurality of layers of adsorbent material, comprising a porous, non-woven fibrous matrix in which is included an adsorbing agent for removing dissolved or suspended matter from the liquid, and a plurality of layers of liquid-permeable material. The layers of adsorbent material and liquid-permeable material are interdigitated in a stack between liquid impervious walls, and the flow of liquid through the filter element is along path generally parallel to the confronting surfaces of the layers of adsorbent material and liquid-permeable material. A process for removing dissolved, suspended or particulate matter from a liquid containing same, utilizing the filter apparatus, is also disclosed.

Abstract: The purification process is carried out in two stages. In the first stage, pulverulent active carbon in finely-divided form is added to the waste water. The solids materials are then separated by conventional mechanical separating processes. The liquid phase prepurified in this manner is then allowed to trickle in a second stage through an active carbon adsorption tower, air being forced at the same time through the adsorption tower. The process has proved particularly valuable in the purification of pesticide-containing waste water.

Abstract: This present invention relates to a method of dehydrating a wet sludge. The wet sludge which is subjected to a preliminary dehydration by gravity dehydration or the like, is pelletized by a pelletizer, and obtained pellets of the sludge are subjected to compression dehydration with a pair of endless filter fabrics.

Abstract: Aqueous mineral slurries containing 10% by weight or more of finely divided mineral solids are flocculated prior to dewatering and/or thickening, and prepared for redispersion, by treating the slurries with polymers comprising at least about 1% by weight 2-acrylamido-2-methyl propyl sulfonic acid copolymerized with acrylamide and/or other suitable water-soluble monomers. The polymers must have a Brookfield viscosity of at least 7000 cps at 7.5% concentration in water. Flocculation of the mineral slurries with these polymers also provides improved re-dispersibility of the dewatered mineral in the filter cake. During redispersion, additional dry mineral may be added to obtain a final solids content as high as 70% or more. The Brookfield viscosity of the final high solids slurry comprising a significant portion of filter cake treated with the flocculants of this invention is lower than that of untreated material.

Abstract: Desulfurization sludge from a flue-gas scrubber operating with calcium-containing additives is dewatered in a thin layer with precipitatable impurities in the liquid phase being precipitated out by neutralization and collected in a thin layer which is then rinsed. The presence of these precipitated impurities on the gypsum which is recovered by this process has not been found to be detrimental to the use of it as a construction material.

Abstract: A method of removing radioactive waste from oil in which all particulates, radioactive contaminants, and moisture are removed from the oil. Particulate matter is removed from the oil by a combination of filtering and heating. Radioactive contaminants are reacted with chlorine to form salts which are removed by filtration. Moisture is removed by use of a flash tank.

Abstract: Wastewater is treated with activated carbon, lime, and filter aid, and subjected to membrane filtration to provide water free from suspended solids and having a TOC level less than about 200 mg/l and total solids less than about 2000 mg/l.

Abstract: An improved dewatering agent for aqueous slurries of mineral concentrates comprising branched dodecylbenzene sulphonic acid used alone or in combination with sodium xylene sulphonate.

Abstract: The present invention relates to a method for the treatment of sludges such as sewage sludges, night soils, water supply sludges, sludged deposition in bottoms of rivers, lakes, harbors and seas and industrial waste water sludges. According to this method, a fiber in an amount of 0.05 to 20% by weight based on solids in a sludge to be treated and an inorganic coagulant or polymeric coagulant are added to the sludge to coagulate the sludge, and water is removed from the coagulated sludge to obtain a filter cake having a low water content.

Abstract: A method for dehydrating sludge, and particularly sewage sludge, includes adding a particulate, thermally expanded volcanic material and a polyelectrolyte to said sludge prior to filtration, said volcanic material having a bulk density of less than 0.09 kg/liter and an average particle size ranging from 20 to 300 microns.

Abstract: A novel process for removing suspended solids from a liquid without loss of heel portion comprising circulating a suspension of a precoat filter aid through a closed chamber provided with at least one vertical tubular, liquid pervious filter aid retainer supported on a tube sheet with the lower pervious section level with said tube sheet until a filter cake is formed on said retainer, pumping a liquid with suspended solids through the chamber whereby clear liquid passes through said filter cake into said retainer where clear liquid is recovered and suspended solids are deposited on filter cake, continuing pumping liquid with suspended solids until a maximum differential pressure is reached, reduce the pumping rate of liquid while simultaneously increasing air pressure to a maximum of 15 psig in the chamber, draining liquid from the chamber through the filter cake and retainer while maintaining air pressure of 2 to 15 psig to recover the heel portion, abruptly back washing liquid through the retainer and filte

Abstract: To avoid formation of toxic trihalomethanes in drinking waters disinfected with halogens, these waters are treated with fine-particle-size ion exchange resin particles, optionally in the presence of a metal salt coagulant, to remove the trihalomethane precursors prior to halogenation.

Abstract: An improved dewatering agent for aqueous slurries of mineral concentrates comprising branched dodecylbenzene sulphonic acid used alone or in combination with sodium xylene sulphonate.

Abstract: A system wherein suspended solids are separated from liquids by passage through a filter after a precoat of filter aid has been deposited on a filter septum. The subsequent addition of filter aid to the liquid and its deposit on the precoat are so regulated that the filter cake produced maintains a practical specific cake resistance to flow therethrough at a preselected value, even if the concentration of suspended solids varies with time, said value being the ratio .DELTA.R/.DELTA.W, where .DELTA.W is a small increment of filter aid weight fed and .DELTA.R is an incremental increase in cake resistance to flow corresponding to that increment .DELTA.W, both increments being on a per unit of filtration area, and the resistance to flow being the differential pressure across the filter cake divided by the flow rate per unit of filtration area.

Abstract: A process and apparatus are disclosed for separating drilling mud and waste materials into pure water and a concentrated solid waste phase which is easily handled and disposed of. The process and apparatus provide for adjusting the pH of the drilling mud and waste materials to be separated, mixing the thus pH adjusted mud and waste materials with a flocculating agent and allowing the solids to settle out. The solids are then removed and further dewatered to produce a relatively dry concentrated solid waste phase. If desired, the clarified water is mixed with finely divided activated charcoal to remove various impurities from the clarified water. The mixture of clarified water and charcoal are then filtered to produce a filtrate stream which is further separated to produce pure water and a liquid phase containing dissolved solids. The pure water can then be reused in the drilling process or safely discharged into the environment.

Abstract: The invention is directed to a process for recovering elemental phosphorus values from phosphorus-containing waste materials. The process comprises reducing the size of the solid particulate materials of the sludge and forming a uniform homogenous sludge which is filtered through a high-pressure thin-cake filter resulting in a filtrate high in phosphorus values.The invention also discloses a pump retrieval means for retrieving the sludge from contaminated disposal areas and a preconditioning dewatering means for thickening and clarifying the sludge prior to comminuting the solids contained therein and filtrating to recover the phosphorus values contained therein.

Abstract: An organic suspension, such as sewage sludge, is conditioned by adding a conditioner and then filtering the suspension through a filter element to form a filter cake on the element. Improved dryness properties of the cake are obtained by using as conditioner during the formation of at least the first half (by weight solids), but not all, of the cake a high molecular weight polyelectrolyte conditioner and by using as conditioner during the formation of the remainder of the cake an inorganic conditioner or a low molecular weight polyelectrolyte conditioner.

Abstract: During the final stages of Al(OH).sub.3 production, deliquoring the aluminum trihydroxide slurry of excess sodium ions in the form of caustic liquor is conventionally achieved by numerous water washes prior to drying the product. Addition of an effective amount of highly charged, high molecular weight anionic polymer flocculant to the aluminum trihydroxide slurry improves the filtration rate, i.e., increases the amount and rate of removal of caustic liquor from the slurry. Addition of the flocculant reduces the amount of washing necessary to remove sodium ions from the final cake and also provides higher cake solids which results in greater production per unit time and less expenditure of energy in the drying process. Anionic polymers derived from 80 to 100% of an anionic vinyl monomer such as acrylic acid and from 20 to 0% of a nonionic vinyl monomer such as acrylamide having molecular weights between 1.5 to 12.0.times.10.sup.6 are useful in deliquoring aluminum trihydroxide slurries.

Abstract: A water treatment process for removing turbidity-causing impurities from water which involves contacting water containing such impurities with a relatively small amount of filter aid material, e.g., diatomaceous earth, for a time sufficient for impurities in the water to become adsorbed on said filter aid material, passing the water containing the filter aid material with impurities adsorbed thereon through a pre-filter having a flow rate of two liters/min./sq. m., or greater, and thereafter through a filter medium in the form of a porous, non-woven matrix consisting essentially of randomly arranged, irregularly intersecting and overlapping cellulose fibers intermixed with micro-bits of an expanded thermoplastic styrene-polymer or lower polyolefin, or of a flexible foamed polyurethane.

Abstract: A process for cleaning oil-contaminated well bore fluids, and particulate solids. An oil-contaminated well bore fluid, or particulate solids, or both, is admixed with an aqueous polymeric solution and diatomaceous earth, and the admixture filtered to free the oil-contaminated well bore fluid, or solids, of oil which is separated therefrom. The oil-decontaminated well bore fluid is thereby rendered suitable for reuse, and residual solids useful for reblending with the original well bore fluid, or rendered environmentally acceptable for discharge.

Abstract: A composition for altering the water function characteristics of a wet, particulate mineral mass combines a surfactant material having an HLB number of from about 6.0 to about 12.0 with a surfactant adsorption inhibitory amount of a coupling agent or hydrotrope. Urea may be added to the composition for the prevention of freezing.

Abstract: A process for the concentration and dewatering of an aqueous suspension of feldspathic minerals, comprising adding to the suspension a filter aid having the general formula: ##STR1## wherein R.sub.1 is an alkyl group of between 8 and 18 carbon atoms and wherein x and y are integers greater than 0 whose sum is between 2 and 15.

Abstract: Reducing the heavy metals content of an aqueous composition which includes adding lime to the composition and filtering the composition.

Abstract: A process for filtering alkaline solutions wherein calcined .alpha.-alumina is used as a filter aid.

Abstract: A composition for altering the water function characteristics of a wet, particulate mineral mass combines a surfactant material having an HLB number of from about 6.0 to about 12.0 with a surfactant adsorption inhibitory amount of a fatty acid substance.

Abstract: A filtration system utilizing a plurality coaxial, vertically disposed, filter elements for clarifying a liquid passed therethrough. Upon the accumulation of a predetermined amount of materials on or in the filter cake, the filter chamber is sealed and the contents drained creating a pressure differential across the filter elements to maintain the integrity of the filter cake on the filter septum. After the contents of the filter chamber have been drained the chamber is positively pressurized to remove any filtrate remaining in the filter cake and to dry the filter cake on the filter septum prior to removal. The expended filter cake and accumulants are removed from the filter septum and conveyed from the filter chamber by a discharge system. The filter chamber is filled with liquid and the filter septum mechanically scrubbed to remove any residual materials therefrom.

Abstract: A method is provided which comprises, adding to the liquid a filtering aid effective amount of a filter aid material consisting essentially of particulate expanded polymer formed by comminuting polymeric foam to eliminate substantially all closed cells of said foam and grading to a desired average particle size range smaller than 100 mesh and larger than about 700 mesh, and filtering the resulting liquid mixture through a filter medium.

Abstract: Radioactive particles are removed from waste or process water and encapsulated by a filtration process wherein the water is filtered through a filter medium composed of a thermoplastic organic polymer. The filter cake so obtained is dried and converted to a solid encapsulating medium by the application of heat and/or pressure. The filter medium comprises, at least partially, a thermoplastic polymer which is wettable by water but non-swelling in water and has a melting point of 100.degree. to 300.degree. C.

Abstract: An improved process for the filtration of phosphoric acid wherein the prefilt phosphoric acid produced from the "wet process" is conditioned with a flocculant and a dispersant and thereafter filtered to concentrate the acid.

Abstract: A method of filtering a coal-derived liquid comprising; mixing the coal liquid with a filter aid material comprising metallic particles; filtering the thus-obtained mixture; subjecting the resulting filter cake material to partial combustion; and separating the metallic particles from the filter cake for reuse as filter aid.