A method for operating a wastewater treatment system is disclosed wherein the wastewater treatment system comprises at least one electrochemical cell comprising dimensionally stable electrodes having the same catalyst composition, the electrodes being immersed in wastewater and being connected to a power supply and wherein the voltage at the power supply is monitored and the polarity of the electrochemical cell(s) is reversed when the recorded voltage increases by a predetermined voltage difference. The wastewater treatment system can comprise at least one electrochemical cell which is kept inactive while the active electrochemical cells are operating. The inactive cell(s) can be activated when all the electrodes of the active cells are consumed as indicated by another increase in voltage at the power supply after the polarity of the active cells has been once reversed.

Provided are electrodialysis systems comprising a plurality of electrodialysis devices, wherein each electrodialysis device of the plurality of electrodialysis devices has a product inlet stream, a product outlet stream, a brine inlet stream, and a brine outlet stream. The product inlet stream for a first electrodialysis device comprises the brine outlet stream of a second electrodialysis device. Further, a first portion of a feed stream is the brine inlet stream for the first electrodialysis device and a second portion of the feed stream is the brine inlet stream for the second electrodialysis device or a third electrodialysis device.

This invention relates to treated geothermal brine compositions containing reduced concentrations of lithium, iron and silica compared to the untreated brines. Exemplary compositions contain concentration of lithium ranges from 0 to 200 mg/kg, concentration of silica ranges from 0 to 30 mg/kg, concentration of iron ranges from 0 to 300 mg/kg. Exemplary compositions also contain reduced concentrations of elements like arsenic, barium, and lead.

A magnetic polymer adsorption material, preparation method and use thereof, which relate to the field of magnetic polymer materials. The preparation method comprises: (1) preparing magnetic nanoparticles; (2) dissolving the magnetic nanoparticles in a pore-forming agent, adding N-vinylpyrrolidone, divinylbenzene and an initiator respectively, and mixing uniformly; (3) adding an emulsifier and a dispersant into an aqueous solution; adding a part of the oil phase solution prepared in step (2) at the temperature below 60° C., and adding the rest of the oil phase solution when the temperature rises to 60° C. or above, reacting with stirring, precipitating and filtering the reacted solution, washing and drying the precipitate, and finally obtaining the magnetic polymer adsorption material. The material has the particle size of 2-100 μm, the magnetization of 5-19.5 emu/g and the specific surface area of 210-950 m.sup.2/g, and can be applied to the adsorption of inorganic and organic matters in solutions, the controlled release of inorganic and organic matters, and the separation of different substances.

A filter medium for removal of contaminants from wastewater. The filter medium includes a walnut shell particle having a metal hydro(oxide) nanoparticle bonded to the surface of the nut shell particle. The filter medium is particularly useful for treating produced water and wastewater generated in steam-assisted gravity drainage (SAGD) in recovery of hydrocarbons from oil sands to remove total organic carbon and silica. Processes for preparing the filter medium and for treating wastewater using the filter medium are also provided.

The present invention provides a composition that includes a silicotitanate that has a sitinakite structure, the composition having higher cesium adsorptivity than conventional compositions. The present invention also provides a production method for the composition that includes a silicotitanate that has a sitinakite structure. The production method does not require the use of hazardous or deleterious materials, can generate a product using a compound that is easily acquired, and can use a general-purpose autoclave. Also provided is a silicotitanate composition that has higher strontium adsorptivity than the present invention. Provided is a silicotitanate composition that contains niobium and a silicotitanate that has a sitinakite structure, the composition having at least two or more diffraction peaks selected from the group consisting of 2θ=8.8°±0.5°, 2θ=10.0°±0.5°, and 2θ=29.6°±0.5°.

A media tank includes a housing having a first housing portion coupled to a second housing portion at an interface between the first and second housing portions, the first and second housing portions collectively defining an interior volume of the housing, and a divider positioned within the interior volume of the housing at the interface between the first and second housing portions to separate the interior volume into a first chamber at least partially defined by the first housing portion and the divider and a second chamber at least partially defined by the second housing portion and the divider. The first housing portion is coupled to the second housing portion via a friction weld at the interface. An annular gap is provided between the divider and the first housing portion. Flash from the friction weld is received within the annular gap.

The present invention relates to a method for recovering metals using an adsorbent, which comprises preparing a leachate comprising metal ions and cyanides, wherein the metal ions comprise gold ions and copper ions; and in a state where the leachate has a cyanide (CN) concentration of 0.1 ppm or greater, adding to the leachate an adsorbent, which has an open circuit potential value between the open circuit potential value of the gold ions and that of the copper ions; and selectively adsorbing the copper ions to the adsorbent.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

A water processing system includes a pretreatment system disposed within the water processing system. The pretreatment system may treat a feed stream including oil and brine and to generate a first brine stream. The pretreatment system includes a first filtration system that may receive the feed stream, the first filtration system may separate the feed stream into a hydrocarbon stream and an intermediate brine stream, the intermediate brine stream includes a plurality of minerals, and the hydrocarbon stream includes water, the oil, and suspended solids. The water processing system also includes a mineral removal system fluidly coupled to and disposed downstream from the first filtration system. The mineral removal system may receive and remove the plurality of minerals from the first brine stream output from the pretreatment system. The mineral removal system includes a first mineral removal unit that may remove a first portion of the plurality of minerals from the first brine stream and to generate a second brine stream. The water processing system also includes a hydrocarbon removal system disposed within the pretreatment system and fluidly coupled to the first filtration system. The hydrocarbon removal system may receive the hydrocarbon stream, to recover the oil, and to generate a recovered oil stream.