Abstract: A process of concentrating an aqueous suspension of solid particles comprising the steps of adding at least one organic polymeric flocculant to the suspension thereby forming flocculated solids in which the flocculated solids are allowed form a layer of solids and thereby forming a more concentrated suspension in which the process comprises the addition of an effective amount of an agent that is selected from the group consisting of free radical agents, oxidizing agents, enzymes and radiation, in which the agent is applied to the suspension prior to or substantially simultaneously with adding the organic polymeric flocculant and/or the organic polymeric flocculant is added to the suspension in a vessel and the agent is applied to the suspension in the same vessel. The process is particularly suitable for solids liquid separation in which the flocculated solids are allowed to settle by sedimentation in a gravity thickener.

Abstract: A method of rehabilitation of a deposition area to render it suitable for plant growth comprising a particulate mineral material, which particulate mineral material has been dewatered from a suspension of said material, comprising the steps of transferring the suspension of particulate mineral material as a fluid to the deposition area, and in which the suspension is allowed to stand and dewater at the deposition area to form a dewatered particulate mineral material, wherein the rehabilitation of the disposal area is achieved by adding a dewatering amount of a polymer to the suspension of the particulate mineral material while it is being transferred as a fluid to the deposition area, wherein the polymer is either a synthetic water-soluble polymer formed from one or more ethylenically unsaturated monomers having an intrinsic viscosity of at least 4 dl/g or a water-soluble polymer that is a natural polymer or semi natural polymer.

Abstract: The present invention relates to a process of concentrating an aqueous suspension of solid particles comprising the steps of adding at least one organic polymeric flocculant to the suspension thereby forming flocculated solids in which the flocculated solids are allowed form a layer of solids and thereby forming a more concentrated suspension in which the process comprises the addition of an effective amount of an agent that is selected from the group consisting of free radical agents, oxidising agents, enzymes and radiation, in which the agent is applied to the suspension prior to or substantially simultaneously with adding the organic polymeric flocculant and/or the organic polymeric flocculant is added to the suspension in a vessel and the agent is applied to the suspension in the same vessel. The process is particularly suitable for solids liquid separation in which the flocculated solids are allowed to settle by sedimentation in a gravity thickener.

Abstract: The present invention relates to a process of concentrating an aqueous suspension of solid particles comprising the steps of adding at least one organic polymeric flocculant to the suspension thereby forming flocculated solids in which the flocculated solids are allowed form a layer of solids and thereby forming a more concentrated suspension in which the process comprises the addition of an effective amount of an agent that is selected from the group consisting of free radical agents, oxidising agents, enzymes and radiation, in which the agent is applied to the suspension prior to or substantially simultaneously with adding the organic polymeric flocculant and/or the organic polymeric flocculant is added to the suspension in a vessel and the agent is applied to the suspension in the same vessel. The process is particularly suitable for solids liquid separation in which the flocculated solids are allowed to settle by sedimentation in a gravity thickener.

Abstract: A process in which a suspension comprising dispersed particulate material in an aqueous medium is transferred as a fluid to a deposition area, then allowed to stand and rigidify, and in which rigidification is improved whilst retaining the fluidity of the suspension during transfer, by combining with the suspension during transfer a rigidifying amount of a treatment system which comprises i) a water-soluble synthetic polymer and ii) a water-soluble natural or seminatural polymer. Improved rigidification can be achieved, including dose efficiency especially in regard to the amount of synthetic polymer required. In addition improvements in the clarity of liquor released from the suspension can be achieved.

Abstract: A process in which a suspension comprising dispersed particulate material in an aqueous medium is transferred as a fluid to a deposition area, then allowed to stand and rigidify, and in which rigidification is improved whilst retaining the fluidity of the suspension during transfer, by combining with the suspension during transfer a rigidifying amount of a treatment system which comprises i) a water-soluble synthetic polymer and ii) a water-soluble natural or seminatural polymer. Improved rigidification can be achieved, including dose efficiency especially in regard to the amount of synthetic polymer required. In addition improvements in the clarity of liquor released from the suspension can be achieved.

Abstract: A method of rehabilitation of a deposition area to render it suitable for plant growth comprising a particulate mineral material, which particulate mineral material has been dewatered from a suspension of said material, comprising the steps of transferring the suspension of particulate mineral material as a fluid to the deposition area, and in which the suspension is allowed to stand and dewater at the deposition area to form a dewatered particulate mineral material, wherein the rehabilitation of the disposal area is achieved by adding a dewatering amount of a polymer to the suspension of the particulate mineral material while it is being transferred as a fluid to the deposition area, wherein the polymer is either a synthetic water-soluble polymer formed from one or more ethylenically unsaturated monomers having an intrinsic viscosity of at least 4 dl/g or a water-soluble polymer that is a natural polymer or semi natural polymer.

Abstract: A process in which material comprising an aqueous liquid with dispersed particulate solids is pumped as a fluid then allowed to stand and rigidify and the rigidification is improved whilst retaining the pump ability of the material by combining polymeric particles with the material during or prior to pumping the material, wherein the polymeric particles comprise water soluble polymer which has an intrinsic viscosity of at least 3 dl/g. The process of the invention more effectively minimises the area taken up by a stack of the material of given volume whilst maintaining the pumpability of the material. This invention is particularly suited to material that comprises red mud from the Bayer alumina process.

Abstract: A process in which material comprising an aqueous liquid with dispersed particulate solids is pumped as a fluid then allowed to stand and rigidify and the rigidification is improved whilst retaining the pumpability of the material by combining polymeric particles with the material during or prior to pumping the material, wherein the polymeric particles comprise water soluble polymer which has an intrinsic viscosity of at least 3 dl/g. The process of the invention more effectively minimises the area taken up by a stack of the material of given volume whilst maintaining the pumpability of the material. This invention is particularly suited to material that comprises red mud from the Bayer alumina process.

Abstract: Aqueous drilling and reservoir fluids are provided comprising polymers with shale and clay inhibition characteristics. These polymers are dissolved in the fluid and are formed from 50 to 100 mo % monomers of formula (I), wherein R.sup.1 is selected from H and C.sub.1 to C.sub.4 alkyl groups; R.sup.2 is selected from C.sub.1 to C.sub.4 alkyl groups, --C(CH.sub.3).sub.2 CH.sub.2 COCH.sub.3, --CH.dbd.CH.sub.2 and --C(CH.sub.3).dbd.CH.sub.2. R.sup.3 is selected from H, C.sub.1 to C.sub.4 alkyl groups, CH.sub.2 .dbd.CH-- and CH.sub.2 .dbd.C(CH.sub.3)--; wherein when R.sup.3 is H or C.sub.1 to C.sub.4 alkyl then R.sup.1 is H and R.sup.2 is --CH.dbd.CH.sub.2 or --C(CH.sub.3).dbd.CH.sub.2 and when R.sup.2 is --C(CH.sub.3).sub.2 CH.sub.2 COCH.sub.3 then R.sup.1 is H; 0 to 50 mol % other ethylenically unsaturated non-ionic monomers and 0 to 20 mol % ionic ethylenically unsaturated monomers and the polymer has a molecular weight of below 1 million.

Abstract: Particulate water-soluble or water-swellable polymeric material is provided with a substantially uninterrupted continuous coating of crystalline material. Single particles or aggregates having a size below 1 mm in size can be made by mixing the polymeric particles with a substantially saturated or supersaturated aqueous solution of crystallizable material (optionally a melt of hydrate crystallizable material) and thereby depositing it as a continuous crystalline coating on the particles.

Abstract: Sulfonated polymers and copolymers are used as thinners in aqueous drilling or packer fluids. The sulfonated polymer has polydispersity below 2 and has a low solution viscosity. It is generally a copolymer of beta-arylamidoalkane sulfonate or allyl sulfonate or other aliphatic sulfonate with an ethylenically unsaturated carboxylic acid, generally acrylic acid.

Abstract: Dispersions in water-immiscible liquid of water-soluble or water-swellable polymer particles are stabilized by use of an aqueous emulsion of water insoluble viscosifying polymer particles that are swellable or soluble in the water-immiscible liquid. After adding the emulsion to the water-immiscible liquid, water is removed from around the particles of the viscosifying polymer, preferably by absorption into the water swellable or soluble polymer particles. Water-immiscible liquids in general can be thickened particularly effectively by use of an aqueous emulsion of water insoluble viscosifying polymer particles that are swellable but insoluble in the water-immiscible liquid. These insoluble particles have a dry size below 10 .mu.m and are formed from monomers of which 80 to 100% are hydrophobic, 30 to 100% are polar and hydrophobic, 0 to 20% are hydrophilic and not more than 30% by weight are aromatic.

Abstract: Aqueous well fluids, such as completion, stimulation and work over fluids contain, as a viscosifier, a polymer having recurring units derived from monomers of the formulaCH.sub.2 .dbd.C(R.sup.1)CONHR.sup.2 NR.sup.3 R.sup.4wherein R.sup.1 is hydrogen or methyl, R.sup.2 is straight or branched chain is C.sub.2-8 alkylene having at least 2 carbon atoms in the backbone and R.sup.3 and R.sup.4 are independently selected from C.sub.1-4 alkyl. Preferred units are derived from dimethylaminopropyl methacrylamide, generally as an acid addition salt. The fluids may contain high ion concentrations. The fluids may be used in processes in which they are maintained downhole for long periods of time at high temperatures.

Abstract: Sulphonated polymers and copolymers are used as thinners in aqueous drilling or packer fluids. The sulphonated polymer has polydispersity below 2 and has a low solution viscosity. It is generally a copolymer of beta-acrylamidoalkane sulphonate or allyl sulphonate or other aliphatic sulphonate with an ethylenically unsaturated carboxylic acid, generally acrylic acid.

Abstract: Water-immiscible liquids, for example oil-based drilling fluids, are thickened by the addition of an aqueous dispersion of polymeric particles that are water-insoluble, and insoluble but swellable polymer, in the water immiscible liquid. The particles have a unswollen average diameter of less than 10 .mu.m and at least 30% by weight are preferably in the range 0.5 to 5 .mu.m. Preferred polymers are formed from more than 80% by weight hydrophobic monomers, preferably alkyl (meth) acrylates, and up to 20% hydrophilic monomers, preferably unsaturated carboxylic acids, preferably acrylic acid.

Abstract: A soil sealing composition suitable for reducing the permeability of soil to water contaminated with electrolyte comprises an expanding lattice clay and a water soluble or water swellable polymer having a molecular weight of at least 500,000 and that is a copolymer of 2-acrylamido-2-methyl propane sulphonic acid, or certain other ethylenically unsaturated sulphonic acids, together with other ethylenically unsaturated monomer, preferably a blend of acrylamide and acrylic acid.

Abstract: Bentonites can be extended for use in drilling muds by addition of a novel polymer blend comprising a low molecular weight water soluble non-ionic or anionic polymer and a high molecular weight anionic polymer.