Abstract: The invention provides methods and compositions for addressing the problem of microorganism infestations and especially biocorrosion in slurry transporting pipelines. The method comprises treating pipeline fluid (especially plug fluid) with an oxidizing biocide in an amount higher than the oxidant demand of the pipeline and a non-oxidizing biocide in an amount less than 30% of the minimum necessary to sterilize the microbiological organisms. This treatment makes use of the unique characteristics of a slurry pipeline to eliminate microorganisms without harming the pipeline as would be expected by using an oxidizing biocide.

Abstract: A method for minimizing the addition of water to a phosphoric acid production process is described. The method uses phosphoric acid to make down a flocculant that is added to the process in order to promote filtration or clarification of crude phosphoric acid. Preferably, the phosphoric acid is a crude, clarified phosphoric acid that is recycled from the phosphoric acid production process itself.

Abstract: The invention provides methods and compositions for addressing the problem of microorganism infestations and especially biocorrosion in slurry transporting pipelines. The method comprises treating pipeline fluid (especially plug fluid) with an oxidizing biocide in an amount higher than the oxidant demand of the pipeline and a non-oxidizing biocide in an amount less than 30% of the minimum necessary to sterilize the microbiological organisms. This treatment makes use of the unique characteristics of a slurry pipeline to eliminate microorganisms without harming the pipeline as would be expected by using an oxidizing biocide.

Abstract: The present disclosure is directed to a method of improving the transfer of slurry in a Bayer process through the addition of one or more chemical species to a Bayer process, wherein said chemical species is selected from the group consisting of: non-ionic surfactants, polyglycols, polyglycol ethers, anionic surfactants, anionic polymers, and a combination thereof. The present invention is also directed to a method of deaerating a slurry in a Bayer process through the addition of an effective amount of one or more chemical species to a Bayer process, wherein said chemical species is selected from the group consisting of: non-ionic surfactants, polyglycols, polyglycol ethers, anionic surfactants, anionic polymers, and a combination thereof.

Abstract: A method for minimizing the addition of water to a phosphoric acid production process is described. The method uses phosphoric acid to make down a flocculant that is added to the process in order to promote filtration or clarification of crude phosphoric acid. Preferably, the phosphoric acid is a crude, clarified phosphoric acid that is recycled from the phosphoric acid production process itself.

Abstract: The present invention provides an inverse emulsion polymer having a dispersed phase composed of an aqueous solution of an acrylic polymer and a continuous phase composed of an ester of a fatty acid and a water-soluble alcohol. The present invention further includes a method of water treatment which includes adding the inverse emulsion polymer to an industrial water system and hydrolyzing the ester of a fatty acid and a water-soluble alcohol into a fatty acid salt. The inverse emulsion polymer may be used as a flocculant to clarify industrial water systems at elevated temperature and/or elevated pressure and high pH.

Abstract: The present disclosure is directed to a method of improving the transfer of slurry in a Bayer process through the addition of one or more chemical species to a Bayer process, wherein said chemical species is selected from the group consisting of: non-ionic surfactants, polyglycols, polyglycol ethers, anionic surfactants, anionic polymers, and a combination thereof. The present invention is also directed to a method of deaerating a slurry in a Bayer process through the addition of an effective amount of one or more chemical species to a Bayer process, wherein said chemical species is selected from the group consisting of: non-ionic surfactants, polyglycols, polyglycol ethers, anionic surfactants, anionic polymers, and a combination thereof.

Abstract: A method for increasing the floccule size and volume of alumina trihydrate during the Bayer processing of bauxite ore using a flocculant in conjunction with a water continuous polymer. The addition of the flocculant and the water continuous polymer to the alumina trihydrate slurry following the security filtration and settling producing trihydrate that is put through the calcination process to produce purified alumina or used as seed for the precipitation process.

Abstract: The present invention is directed to improvements in the Bayer mining process, used for the recovery of alumina from bauxite ore. Water-continuous emulsion polymers are advantageously used to improve the clarification, filtration and scale control of red-mud containing liquors generated during the Bayer process. Preferred polymers are high molecular weight poly(methyl acrylate/acrylic acid), poly(methyl acrylate), poly(vinyl acetate/acrylic acid/methyl acrylate) and a combination of a high molecular weight poly(methyl acrylate/acrylic acid) with a lower molecular weight poly(methyl acrylate/acrylic acid).

Abstract: In the Bayer process for producing alumina from bauxite of the type wherein the bauxite is added to a caustic solution to produce a soluble aluminate solution and an insoluble red mud fraction which is then subjected to one or more separation steps to produce a thickener overflow which is then subjected to a Sand Filter to polish the thickener overflow the improvement which comprises treating the thickener overflow with a solids removal efficiency improving amount of a biopolymer.

Abstract: A process for improving the flocculation of suspended solids in a Bayer process liquor in a primary settler stage. The method includes the step of adding to a primary settler feed from about 1 to about 100 parts per million of a composition including a non-inverted, water-continuous polymer, said polymer being hydrolyzable in a Bayer process liquor to an acid form, said acid form being an active red mud flocculant.

Abstract: Bayer process liquors derived from the digestion of bauxites with a caustic solution are purified by removing the organic impurities present in the liquors. Removal of these impurities is accomplished by treating the liquor containing dispersed solids with a high viscosity polymer which includes diallyl dimethyl ammonium monomers.