A system and method for generating base water and precipitate, including combining produced water with seawater to precipitate barium sulfate from barium in the produced water and from sulfate in the seawater, and separating the precipitate to give the base water and the precipitate. The base water may have less than a specified amount of sulfate and be utilized for hydraulic fracturing fluid. The precipitate may give a weighting agent for drilling.

A universal chemical processor (UCP) including a reactor vessel having a central longitudinal axis and main chamber comprises a first inlet port for a main feedstock, a second inlet port for a fluidizing medium and a third inlet port for one or more reactants. The UCP also includes a reactive radioactive chemical processor (R.sup.2CP) that contains a radioactive element positioned extending along the longitudinal axis in the main chamber. In operation, a fluidized bed can be supported in the main chamber when a fluidizing medium and feedstock are supplied to the main chamber through the first and second inlet ports and the radioactive element of the R.sup.2CP emits ionizing radiation that is capable of ionizing feedstock and reactants, inducing chemical reactions, and sterilizing and decomposing any organic materials within a radiation zone.

Methods for removing heavy metals from a phosphoric acid solution produced in a wet process for manufacturing phosphoric acid, comprising treating the wet-process phosphoric acid solution with a small amount of a solid adsorbing material and a complex reagent to form a heavy metal complex-contaminated solid adsorbing material, and removing the contaminated solid adsorbing material to yield a treated phosphoric acid solution having a low heavy metal content.

A system and method of desalinating a brine stream are provided. The multistage desalination process with carbon dioxide capture recovers valuable products where the reject brine is passed through seven stages. In each stage, a specific metal ion is recovered. In stage 1, a ˜100% recovery of magnesium ions as magnesium hydroxide solid was obtained by chemical reaction with ammonia solution. In stage 2, Na.sup.+ reduction, as sodium bicarbonate, and CO.sub.2 uptake was achieved. In stage 3, electrocoagulation (EC) was used to recover sulfate ions as pure calcium sulfate solid and to regenerate NH.sub.3 as ammonium hydroxide. In stage 4, CaO was added to the treated brine. In stage 5, more recovery of NaHCO.sub.3 was attained by adding ammonium bicarbonate, while in stage 6, the treated brine mixture was passed through another modified Solvay process. In stage 7, EC was again used to recover CaCl.sub.2 solution and NH.sub.3 compounds.

A system and method of desalinating a brine stream are provided. The multistage desalination process with carbon dioxide capture recovers valuable products where the reject brine is passed through seven stages. In each stage, a specific metal ion is recovered. In stage 1, a ˜100% recovery of magnesium ions as magnesium hydroxide solid was obtained by chemical reaction with ammonia solution. In stage 2, Na.sup.+ reduction, as sodium bicarbonate, and CO.sub.2 uptake was achieved. In stage 3, electrocoagulation (EC) was used to recover sulfate ions as pure calcium sulfate solid and to regenerate NH.sub.3 as ammonium hydroxide. In stage 4, CaO was added to the treated brine. In stage 5, more recovery of NaHCO.sub.3 was attained by adding ammonium bicarbonate, while in stage 6, the treated brine mixture was passed through another modified Solvay process. In stage 7, EC was again used to recover CaCl.sub.2 solution and NH.sub.3 compounds.

A system and method for producing minerals from divalent ion-containing brine stream includes rejecting sulfate from a divalent-ion rich reject stream in a first nanofiltration seawater reverse osmosis (NF-SWRO) unit, producing solid calcium sulfate dihydrate and a magnesium-rich brine stream in a first concentration unit, concentrating the magnesium-rich brine stream to a saturation point of sodium chloride in a second concentration unit, producing solid sodium chloride and a supernatant product stream in a first crystallizing unit, produce a concentrated magnesium-rich bittern stream from the supernatant product stream in a third concentration unit, and at least one of producing hydrated magnesium chloride from the concentrated magnesium-rich bittern stream in a second crystallizing unit and producing anhydrous magnesium chloride by prilling the concentrated magnesium-rich bitterns stream under a hydrogen chloride atmosphere in a dry air process unit.

A system and method for producing minerals from divalent ion-containing brine stream includes rejecting sulfate from a divalent-ion rich reject stream in a first nanofiltration seawater reverse osmosis (NF-SWRO) unit, producing solid calcium sulfate dihydrate and a magnesium-rich brine stream in a first concentration unit, concentrating the magnesium-rich brine stream to a saturation point of sodium chloride in a second concentration unit, producing solid sodium chloride and a supernatant product stream in a first crystallizing unit, produce a concentrated magnesium-rich bittern stream from the supernatant product stream in a third concentration unit, and at least one of producing hydrated magnesium chloride from the concentrated magnesium-rich bittern stream in a second crystallizing unit and producing anhydrous magnesium chloride by prilling the concentrated magnesium-rich bitterns stream under a hydrogen chloride atmosphere in a dry air process unit.

A method for sequestering CO.sub.2 by creating precipitated calcium carbonates including Calcite, Dolomite, Vaterite and Struvite; (1) Utilizing a mutually beneficial bacterial/algal colony that can fix CO.sub.2 as Calcite, Dolomite, Vaterite and Struvite (2) providing sunlight, water, CO.sub.2 from either the air or industrial waste streams; and (3) assisting microbial/algal induced carbonate precipitation of Calcite, Dolomite, Vaterite and Struvite, thereby sequestering most of the CO.sub.2 introduced in step (2). In addition, chlorine, sulfur, H.sub.2S, NOx and toxic heavy metals will be fixed into the Calcite, Dolomite, Vaterite and/or Struvite matrix, rendering them environmentally harmless.

A process may involve digesting raw phosphate with concentrated sulfuric acid and converting the raw phosphate to calcium sulfate in the form of dihydrate and/or hemihydrate, and phosphoric acid, separating off calcium sulfate as solid from a liquid phase of a suspension that is obtained, treating the calcium sulfate that is separated off or from a stockpile with an acid to give a suspension with purified calcium sulfate and P.sub.2O.sub.5-containing acid solution, separating off the purified calcium sulfate as solid from a liquid phase of a suspension obtained, using the P.sub.2O.sub.5-containing liquid phase as a portion of the sulfuric acid required for digesting the raw phosphate or as feedstock for treating phosphogypsum from the stockpile to give a suspension of purified calcium sulfate and P.sub.2O.sub.5-containing acid solution, which is thereafter processed.

A method for separating a particulate stream of an evaporite mineral feedstock, the method comprising passing the stream to an air classifier configured to separate the particulate stream into a fine component and a coarse component.