Disclosed are a recyclable clean fracturing fluid thickener, a preparation method and a recovery method thereof, and a high-temperature resistant clean fracturing fluid, which relate to the stimulation treatment of oil and gas fields. Diethanolamine and thionyl chloride are used as raw materials and reacted to obtain an intermediate, which is then reacted with an unsaturated fatty acid amidopropyl dimethylamine to produce the recyclable clean fracturing fluid thickener. The clean fracturing fluid can be used in the fracturing stimulation treatment of low and medium permeability reservoirs.

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.

A process mechanically breaks colloidal suspension bonds with the surrounding fluids through high energy impact with a stationary plate or a colliding fluid stream. The fluid with a colloidal suspension is pumped through one or more to 3 nozzles to collide with either a stationary plate in an impact chamber at high velocity, or another similar or different fluid stream. The process breaks the bonds maintaining the colloidal suspension, disassociates these materials, and allows for gravity or chemical separation of the previously colloidal particles from the fluid. The process can separate colloidal particles from a liquid medium through pressurization followed by high energy impact and rapid release.

A method of treating a contaminated oil comprising preparing a brine solution, adding ozone to the brine solution to produce ozonated brine solution, adding a volume of ozonated brine solution to a volume of the contaminated oil, mixing the volumes of contaminated oil and ozonated brine solution with coagulant and surfactant at a shear rate sufficiently high so as to cause formation of an emulsion of the contaminated oil and the brine solution, stopping the mixing, thereby causing the emulsion to separate into an aqueous brine liquid phase and an oil liquid phase, separating the brine liquid phase from the oil liquid phase, and separating at least one contaminant from the oil liquid phase to produce a volume of purified oil.

Waste water is remanufactured with ozone in a series of mixing vessels. The ozone is dispersed to both a top and a bottom portion of each mixing vessel, but in different amounts. This creates an electrical potential difference across the height of each mixing vessel which significantly improves the oxidation of organic carbon-based impurities and eliminates H.sub.2S and bacteria. Sludge and solids floating to the top of each mixing vessels are removed, as well as sludge and solids settling to the bottom of the mixing vessels. When oil and gas well waste water is treated in this manner, the resulting treated water is purified and has a high salt content suitable for oil or gas well injection.

A method of removing a soluble metal ion from a contaminated brine fluid comprising: adding lime to the contaminated brine fluid, wherein the lime causes the soluble metal ion to become insoluble in the contaminated brine fluid; and passing the contaminated brine fluid through a filter media, wherein the step of passing is performed after the step of adding, and wherein after the brine fluid is passed through the filter media, a brine fluid having a reduced concentration of the metal ion is produced. Another method of removing a soluble metal ion from a contaminated brine fluid comprises: passing the contaminated brine fluid through a filter media, wherein the filter media comprises the lime.

A water treatment apparatus, system and method including introducing an aqueous fluid into a chamber, the aqueous fluid having a pH below 7 and having an oxidizing agent. Contacting, within the chamber, the aqueous fluid with a corrodible sacrificial material which oxidizes in the presence of the oxidizing agent also reducing the oxidizing agent. Thereafter, adjusting, subsequent contacting the corroding particulate, the pH of the aqueous fluid to above 7.

Disclosed are a recyclable clean fracturing fluid thickener, a preparation method and a recovery method thereof, and a high-temperature resistant clean fracturing fluid, which relate to the stimulation treatment of oil and gas fields. Diethanolamine and thionyl chloride are used as raw materials and reacted to obtain an intermediate, which is then reacted with an unsaturated fatty acid amidopropyl dimethylamine to produce the recyclable clean fracturing fluid thickener. The clean fracturing fluid can be used in the fracturing stimulation treatment of low and medium permeability reservoirs.

Process for producing hydrophobically associating polyacrylamides Summary Process of manufacturing hydrophobically associating polyacrylamides comprising at least acrylamide or derivatives thereof and an associative monomer by adiabatic gel polymerization of an aqueous monomer solution, wherein the concentration of the monomers in the aqueous solution is from 1 mole/kg to 3.3 mole/kg, relating to the total of all components of the aqueous monomer solution. The process yields hydrophobically associating polyacrylamides having an improved viscosity efficiency. Hydrophobically associating polyacrylamides obtainable by the process of the present invention and use of such hydrophobically associating polyacrylamides for oilfield applications, in particular for enhanced oil recovery, conformance control and hydraulic fracturing.

A process mechanically breaks colloidal suspension bonds with the surrounding fluids through high energy impact with a stationary plate or a colliding fluid stream. The fluid with a colloidal suspension is pumped through one or more to 3 nozzles to collide with either a stationary plate in an impact chamber at high velocity, or another similar or different fluid stream. The process breaks the bonds maintaining the colloidal suspension, disassociates these materials, and allows for gravity or chemical separation of the previously colloidal particles from the fluid. The process can separate colloidal particles from a liquid medium through pressurization followed by high energy impact and rapid release.