Methods and systems for calcining dewatered tailings and/or mine waste are disclosed herein. In some embodiments, the method comprises (i) processing dewatered tailings comprising clay minerals, (ii) calcining the processed tailings to produced calcined tailings, and (iii) altering a composition and/or one or more characteristics of the calcined tailings to produce a cementitious product. Altering the composition can include blending the calcined tailings with one or more additives, such as lime, dolomitic lime, lime kiln dust, argillaceous limestone, limestone, pulverized quicklime, ground calcium carbonate, quicklime, gypsum, natural pozzolans, artificial pozzolans, water, flow aids, or the like.

Terpolymers and use thereof are provided comprising one or more nonionic monomers, one or more anionic monomers and one or more cationic monomers, These terpolymers and compositions containing may be used as flocculants, for example, for treating tailings, such as oil sands tailings, to facilitate solid-liquid separation, for example, in order to efficiently recycle water and/or to reduce the volume of tailings which may be transferred to a tailings pond and/or to a dedicated disposal area.

Terpolymers and use thereof are provided comprising one or more nonionic monomers, one or more anionic monomers and one or more cationic monomers, These terpolymers and compositions containing may be used as flocculants, for example, for treating tailings, such as oil sands tailings, to facilitate solid-liquid separation, for example, in order to efficiently recycle water and/or to reduce the volume of tailings which may be transferred to a tailings pond and/or to a dedicated disposal area.

An industrial waste salt resourceful treatment method comprises the following steps: the industrial waste salt is sequentially subject to dissolving, chemical pre-purification, deep purification, organic matter concentration reduction, adsorption and oxidation decolorization and multi-effect evaporative crystallization to respectively obtain sodium sulfate, sodium chloride and sodium nitrate crystals; the crystallization temperature of sodium sulfate is in a range of 75° C. to 85° C.; the crystallization temperature of sodium chloride is in a range of 60 to 70° C.; and the crystallization temperature of sodium nitrate is in a range of 45° C. to 55° C. An industrial waste salt resourceful treatment device is further provided.

Methods and systems for calcining dewatered tailings and/or mine waste are disclosed herein. In some embodiments, the method comprises (i) processing dewatered tailings comprising clay minerals, (ii) calcining the processed tailings to produced calcined tailings, and (iii) altering a composition and/or one or more characteristics of the calcined tailings to produce a cementitious product. Altering the composition can include blending the calcined tailings with one or more additives, such as lime, dolomitic lime, lime kiln dust, argillaceous limestone, limestone, pulverized quicklime, ground calcium carbonate, quicklime, gypsum, natural pozzolans, artificial pozzolans, water, flow aids, or the like.

Methods and systems for treating tailings at an elevated pH using lime are disclosed herein. In some embodiments, the method comprises (i) providing a tailings stream comprising bicarbonates and a pH less than 9.0, (ii) adding a coagulant comprising calcium hydroxide to the tailings stream to form a mixture having a pH of at least 11.5 and a soluble calcium level no more than 800 mg/L, and (iii) dewatering the mixture to produce a product having a solids content of at least 40% by weight. In some embodiments, the pH and soluble calcium level of the mixture cause chemical modification of clay materials of the mixture via pozzolanic reactions. In some embodiments, the undrained shear strength of the product increases over a period of time of at least two days.

Processes of thickening slurries such as from metal and non-metal based ore processes are disclosed. The processes include treating a feed slurry in a thickener apparatus with an indifferent salt in sufficient quantity to increase efficiency of solids-liquid separation as compared to a feed slurry in the thickener apparatus without the added indifferent salt.

A method of separating sludge which involves adding an insoluble mineral colloidal suspension into an industrial sludge to destabilize the industrial sludge and separating destabilized components of the industrial sludge. The insoluble mineral colloidal suspension includes magnesium hydroxide. In an alternative embodiment dry finely divided magnesium hydroxide can be added and then dispersed into an industrial sludge. Conventional flocculants and/or coagulants can also be added. Conventional physical separation processes can be used to separate the destabilized industrial sludge.

A method of separating sludge which involves adding an insoluble mineral colloidal suspension into an industrial sludge to destabilize the industrial sludge and separating destabilized components of the industrial sludge. The insoluble mineral colloidal suspension includes magnesium hydroxide. In an alternative embodiment dry finely divided magnesium hydroxide can be added and then dispersed into an industrial sludge. Conventional flocculants and/or coagulants can also be added. Conventional physical separation processes can be used to separate the destabilized industrial sludge.

Waste solidification compositions and methods of using them repurpose calcium-containing industrial by-products. The compositions comprise either 1) a) auto shred residue; and b) a particulate wood-based product, or 2) a) a solid, particulate calcium-containing compound; and b) a superabsorbent material. The method of repurposing a solid, particulate calcium-containing industrial by-product comprises a) blending the by-product with a superabsorbent material to form a waste solidification composition; b) adding the waste solidification composition to a liquid industrial waste stream; and c) allowing the waste solidification composition to absorb at least 1 times its weight of the liquid industrial waste stream to form a solid waste product. The solid waste product passes Paint Filter Liquids Test Method 9095B.