Methods and systems for treating oil sands tailings streams at an elevated pH using lime are disclosed herein. In some embodiments, the method comprises providing a tailings stream including 10-55% solids by total weight, increasing the pH of the tailings stream by combining the tailings stream with lime to produce a lime-tailings mixture having a pH of at least 11.0, and dewatering the lime-tailings mixture to produce a first stream having 10% or less solids by total weight and a second stream having 50% or more solids by total weight. The first stream can correspond to a release water stream, and the second stream can correspond to a cake. The lime slurry can include about 10% lime by total weight, and can comprise lime hydrate, quicklime, or a combination thereof. Dewatering the lime-tailings mixture can include routing the lime-tailings mixture to a centrifuge unit and/or a pressure or vacuum filtration unit.

Methods and systems for treating oil sands tailings streams at an elevated pH using lime are disclosed herein. In some embodiments, the method comprises providing a tailings stream including 10-55% solids by total weight, increasing the pH of the tailings stream by combining the tailings stream with lime to produce a lime-tailings mixture having a pH of at least 11.0, and dewatering the lime-tailings mixture to produce a first stream having 10% or less solids by total weight and a second stream having 50% or more solids by total weight. The first stream can correspond to a release water stream, and the second stream can correspond to a cake. The lime slurry can include about 10% lime by total weight, and can comprise lime hydrate, quicklime, or a combination thereof. Dewatering the lime-tailings mixture can include routing the lime-tailings mixture to a centrifuge unit and/or a pressure or vacuum filtration unit.

A method and a system for treatment of a spent chloroaluminate ionic liquid catalyst and an alkaline wastewater, where the method includes: 1) mixing the catalyst with a concentrated brine for hydrolysis reaction until residual activity of the catalyst is completely eliminated, to obtain an acidic hydrolysate and an acid-soluble oil; 2) mixing the acidic hydrolysate with an alkaline solution containing the alkaline wastewater for neutralization reaction until this reaction system becomes weak alkaline, to obtain a neutralization solution; 3) fully mixing the neutralization solution with a flocculant, carrying out sedimentation and separation, collecting the concentrated brine at an upper layer for reuse in the hydrolysis reaction, and collecting concentrated flocs at a lower layer; 4) dehydrating the concentrated flocs to obtain concentrated brine for reuse into the hydrolysis reaction, and collecting a wet solid slag; and 5) drying the wet solid slag to obtain a dry solid slag.

The systems and methods disclosed herein process produced/flowback water, such as high total dissolved solids produced water, to generate high purity, high value products with little to no waste. The generated high purity, high value products include caustic soda, hydrochloric acid, and/or sodium hypochlorite. Further, the methods and systems disclosed herein generate high quality brine for electrolysis through the systematic removal of contaminants such as but not limited to suspended solids, iron, sulfides, barium, radium, strontium, calcium, magnesium, manganese, fluoride, heavy metals, organic carbon, recoverable hydrocarbons, silica, lithium, and/or nitrogen containing compounds. Further, some products generated by the systems and methods disclosed herein may be recovered and reutilized or sold for other uses, such as carbon dioxide, calcium oxide, chlorine, magnesium oxide, calcium carbonate, and/or barium sulfate.

A process for reducing the production of sludge by municipal or industrial wastewater purification plants, comprising a step of mesophilic or thermophilic anaerobic digestion (20), or anaerobic digestion combining these two operating modes, of a stream of sludge to be treated (1), and at least one biological solubilization anaerobic treatment step (30); the process comprises, upstream of the anaerobic digestion step, a step of dehydration (10) of the sludge to be treated, followed by a step of mixing (15) the dehydrated sludge with a recirculated fraction of sludge that is more liquid, originating from recycling of the digestion (20), and/or from the anaerobic treatment step (30), and/or centrates originating from a final dehydration (50) of the treated sludge, wherein the recirculation rate is chosen such that the mixture has a dryness suitable for digestion, this mixture then being directed towards the digestion.

The invention relates to a method for treating an aqueous fluid, comprising bringing into contact the aqueous fluid with a fluidised bed of powdered activated carbon, and separating the aqueous fluid from the bed of powdered activated carbon, including a step of managing the fluidised bed of powdered activated carbon. The management step comprises the extraction of a fraction of the fluidised bed of powdered activated carbon in the form of sludge, at least a separation of the sludge extracted in the previous step so as to obtain a fraction having an insoluble index HCl which is higher than that of the sludge before separation by at least 5 percentage points, and a reinjection of said fraction into the fluidised bed of powdered activated carbon.

A system for processing drilling mud, the system including a primary separation tank having an inlet for receiving drilling waste and an outlet in fluid communication with a feed line, and an injection pump in fluid communication with a polymer tank and the feed line. The system also includes a clarifying tank in fluid communication with the feed line and a first collection tank, wherein effluent from the clarifying tank is discharged into the first collection tank, and a centrifuge in fluid communication with the clarifying tank and a second collection tank, wherein effluent from the centrifuge is discharged into the second collection tank.

A method enhancing biological digestion of wastewater sludge is provided. The method uses chlorine dioxide to accelerate and improve the efficiency of aerobic or anaerobic digestion.

Disclosed is a rotational flow rotation deoiling method for oil-based mud rock debris. The method comprises the following steps: (1) System viscosity control, wherein by means of heat exchange between a gas medium and the rock debris, the viscosity of the oil-based mud debris is reduced to reduce the interaction force between oil, water, and the surface and channels of solid particles, thereby facilitating the separation in a rotational flow field; (2) Rotational flow rotation deoiling, wherein the oil-based mud rock debris particles undergo a coupled motion of rotation and revolution, wherein by means of the rotation of the rock debris particles, the centrifugal desorption of oil on the surface of a solid phase, oil in capillaries and oil in pores is enhanced; and by means of the centrifugal force of periodic oscillation generated by the revolution thereof, the separation and enrichment of oil and gas and the solid phase are completed, thereby achieving the removal of the oil phase from the pore channels of the rock debris; and (3) gas-liquid separation and reuse, wherein an oil-containing mixture produced in step (2) is subjected to gas-liquid separation so as to realize the reuse of a base oil, circulation of the gas medium, and a harmless treatment of the rock debris; and a rotational flow rotation deoiling device for oil-based mud rock debris is further comprised.

Disclosed is a rotational flow rotation deoiling method for oil-based mud rock debris. The method comprises the following steps: (1) System viscosity control, wherein by means of heat exchange between a gas medium and the rock debris, the viscosity of the oil-based mud debris is reduced to reduce the interaction force between oil, water, and the surface and channels of solid particles, thereby facilitating the separation in a rotational flow field; (2) Rotational flow rotation deoiling, wherein the oil-based mud rock debris particles undergo a coupled motion of rotation and revolution, wherein by means of the rotation of the rock debris particles, the centrifugal desorption of oil on the surface of a solid phase, oil in capillaries and oil in pores is enhanced; and by means of the centrifugal force of periodic oscillation generated by the revolution thereof, the separation and enrichment of oil and gas and the solid phase are completed, thereby achieving the removal of the oil phase from the pore channels of the rock debris; and (3) gas-liquid separation and reuse, wherein an oil-containing mixture produced in step (2) is subjected to gas-liquid separation so as to realize the reuse of a base oil, circulation of the gas medium, and a harmless treatment of the rock debris; and a rotational flow rotation deoiling device for oil-based mud rock debris is further comprised.