Methods, systems, and apparatus, relate to a method for carbon capture from sea water. A first source of sea water into a reverse osmosis chamber. Reverse osmosis is performed on the sea water to produce fresh water and brine. The brine is provided to an electrolyzer. A current is passed through the brine and fresh water, thereby producing a hydroxide solution in a cathode chamber of the electrolyzer. The hydroxide solution is collected and placed into a contacting chamber and new sea water introduced. Precipitates are produced comprising at least calcium carbonate and magnesium carbonate.

A method to improve the solid/solid separation of an amorphous aluminium trihydroxide containing suspension from a gypsum containing suspension in a saturated calcium sulphate solution without the need for a dewatering step following the solid-solid separation.

A treatment for a large body of water to make the water suitable for recreational purposes is disclosed. A sedimentation zone and a dissipation zone are designated in the water body. A disinfection method based on a CT index and a flocculant composition are utilized in the sedimentation zone to aid in the settling of different microorganisms and/or contaminants. Also, the water in the sedimentation zone is minimally disturbed to facilitate the sedimentation process. A permanent chlorine residual is maintained in the dissipation zone by adding an efficient amount of a chlorine disinfectant such that at least a 0.5 mg/L free chlorine level is maintained in the water volume. Water is injected into the dissipation zone by means of one or more inlet nozzles. Along with natural currents produced by winds and water temperature differences, a water dissipation pattern from within the dissipation zone into the sedimentation zone is generated.

In a process for treating wastewater from a combined gasification and Fischer-Tropsch (F-T) process, feedstock derived from Municipal Solid Waste or the like is gasified in a reactor (R) and treated in a cleanup unit (C) which generates a first wastewater stream (1st WWT STREAM) containing salts and inorganic pollutants. The first wastewater stream is treated in a treatment unit (T1) to remove inorganic pollutants derived from the syngas The treatment comprises a) degassing, and subsequently b) neutralising the first wastewater stream before treatment in a Dissolved Air Flotation unit (72c) and filtering in a moving sand bed or similar (72d) to remove solids, and a stripping process to remove ammonia. A second wastewater stream (2.sup.nd WWT Stream) containing organic pollutants but being low in salts arises from the F-T process and is treated separately to allow recycling within the F-T process.

An apparatus for treating a stream of contaminated water having an elevated concentration of at least one of light metals, heavy metals, sulfates that includes at least one process fluid inlet communicating with a process conduit; at least one electrode reaction vessel in fluid communication with the process conduit, the reaction vessel having an interior chamber and at least one electrode positioned in the reaction chamber, the electrode powered by a alternating current source; and at least one magnetic field reaction vessel in fluid communication with the process conduit, the magnetic field reaction vessel having an outwardly oriented surface and an opposed inwardly oriented surface, the magnetic field reaction vessel having at least one magnet in contact with the inwardly oriented surface of the magnetic field reaction vessel.

The invention relates to a technique for handling liquid radioactive waste from a nuclear fuel-energy cycle, and may be used in a process for processing liquid radioactive waste for maximally reducing the volume thereof and removing radionuclides by concentrating same in a solid phase. The aim is achieved by means of a method for processing liquid radioactive waste and for the recovery thereof, including waste oxidation, separating sludge, colloids and suspended particles from a liquid phase, and removing, from the liquid phase, radionuclides to be subsequently recovered using selective sorbents and filters; the method is characterized in that, prior to the stage for separating sludge, colloids and suspended particles from the liquid phase of the radioactive waste, selective sorbents in the form of powders are added and mixed into the liquid waste.

Methods for removing a soluble heavy metal-sulfur complex from a process solution comprise contacting the process solution with an oxidant to oxidize the heavy metal-sulfur complex and form an oxidized complex precipitate, or with an acid to acidify the heavy metal-sulfur complex and form an acidified complex precipitate, and removing the precipitate from the process solution to provide a heavy metal-reduced solution. The method is advantageous for removing heavy metals such as mercury, cadmium, barium, iron, vanadium and/or manganese from process solutions, for example originating from natural gas production, petroleum production, water treatment or mining.

Method for dewatering sludge assisted by flocculating reagent, said method comprising an injection of flocculating reagent into the sludge and a step for dewatering said sludge, characterized in that it comprises a preliminary step for mixing (4) said sludge so as to destructure it and reduce its viscosity. Installation for implementing this method.

Disclosed are methods of treating wastewater using a membrane bioreactor and achieving a target phosphorus concentration for the membrane permeate stream. These methods include the steps of dosing a wastewater stream with a rare earth clarifying agent and passing the dosed wastewater stream through the membrane to obtain a membrane permeate stream with a permeate concentration that is less than the phosphorus concentration of the influent stream. This permeate concentration also can be equal to or less than a target phosphorus concentration. In the methods as disclosed herein, the rare earth clarifying agent can be chloride salts of one or more rare earth elements and in certain embodiments, the rare earth clarifying agent can be CeCl.sub.3 and LaCl.sub.3.

Various illustrative embodiments of a process for enhanced flocculation and clarification of produced water from oil and gas wells using nanoparticles are provided herein. Certain nanoparticles can increase the settling rate of solids in produced water when used alone or combined with certain conventional flocculents.