Abstract: An advanced defluoridation agent and a method for removing fluoride ions in fluorine-containing wastewater are provided. The advanced defluoridation agent includes 40-70 wt % of polyaluminum sulfate, 0.3-30 wt % of hydroxyapatite and deionized water supplemented to 100 wt %. Using the advanced defluoridation agent of the present disclosure to treat fluoride-containing wastewater can achieve increased defluorination efficiency, reduced electrical conductivity, and reduced sludge content, and a better defluorination effect. The concentration of fluoride ions is lower than 15 ppm after using the advanced defluoridation agent of the present disclosure.

Abstract: A two-stage system and method for treating fluoride-containing wastewater are provided. The two-stage system includes a first concentration defluoridation section and a second concentration defluoridation section. In the first concentration defluoridation section, the first mixed wastewater containing high concentration of fluoride ions is mixed with calcium chloride and stirred in the second mixing tank to obtain the second mixed wastewater containing low-concentration fluoride ions; in the second concentration defluoridation section, the second mixed wastewater is mixed with an advanced defluoridation agent and stirred in the third mixing tank to form a third mixed wastewater; the third mixed wastewater is introduced into a flocculation tank from the third mixing tank; and polymer is added for flocculation and sedimentation, so as to discharge a sediment and a defluoridation wastewater, the fluoride ion of which is less than 15 ppm.

Abstract: A recycling system and method for treating waste sulfuric acid solution containing hydrogen peroxide are provided. The recycling system includes a preheat subsystem, a reaction cycle control subsystem, and a cooling subsystem. The preheat subsystem heats the waste sulfuric acid solution to a target temperature through a cyclic heat exchange method and then further raises the temperature using an acid-resistant heater. The reaction cycle control subsystem monitors the sulfuric acid concentration, hydrogen peroxide content, reaction temperature, and nitrate compound content of the waste sulfuric acid solution to determine the amount and mode of addition of a nitrate-containing promoter. The cooling subsystem includes a first cooling heat exchanger to transfer waste heat to the initial waste sulfuric acid solution and a second cooling heat exchanger to reduce the sulfuric acid to a safe temperature, thereby avoiding overheating.

Abstract: A method and device of removing and recycling metals from a mixing acid solution, includes adsorbing a mixing acid solution with a pH value of ?1 to 4 and a cobalt ion concentration of 100 to 1,000 mg/L by at least two cation resins in series setting to the cobalt ion concentration in the mixing acid solution is less than 10 mg/L, and then adjusting the pH value of the mixing acid solution after adsorption to meet a discharge standard, wherein the particle size of the at least two cation resins in series setting is 150˜1,200 ?m. After the cation resins are saturated by adsorption, regenerating the cation resins by sulfuric acid to form a cobalt sulfate solution, and then electrolytically treating the cobalt sulfate solution to obtain electrolytic cobalt and sulfuric acid electrolyte. The operation process is simple without complicated equipment, and it can effectively recycle metals from mixing acid solutions.

Abstract: A method for treating wastewater containing ertriazole compounds is provided. Hypochlorous acid (HOCl) having a neutral to slightly acidic pH value is added to the wastewater containing triazole compounds for reaction, thereby effectively reacting more than 90% of triazole compounds.

Abstract: A method and device of removing and recycling metals from a mixing acid solution, includes adsorbing a mixing acid solution with a pH value of ?1 to 4 and a cobalt ion concentration of 100 to 1,000 mg/L by at least two cation resins in series setting to the cobalt ion concentration in the mixing acid solution is less than 10 mg/L, and then adjusting the pH value of the mixing acid solution after adsorption to meet a discharge standard, wherein the particle size of the at least two cation resins in series setting is 150˜1,200 ?m. After the cation resins are saturated by adsorption, regenerating the cation resins by sulfuric acid to form a cobalt sulfate solution, and then electrolytically treating the cobalt sulfate solution to obtain electrolytic cobalt and sulfuric acid electrolyte. The operation process is simple without complicated equipment, and it can effectively recycle metals from mixing acid solutions.

Abstract: A water treatment system is provided with a nitrogen-containing organic compound oxidizing device that treats the first-stage treatment water after filtration and removal of cation ions. An oxidant-containing water stream and an inorganic bromide-containing water stream are respectively added into a pipeline that conducts the first-stage treatment water and then pass through an in-pipe mixer and a mixing unit, whereby to oxidize the nitrogen-containing organic compounds in the first-stage treatment water and then form the second-stage treatment water for output.

Abstract: A recycled water treatment system is equipped with different bio-treatment devices to decompose nitrogen-containing inorganic compounds and nitrogen-containing organic compounds in order to enhance efficiency of treating nitrogen-containing organic compounds, wherein an organism-carrying fixed-bed unit is used to efficiently decompose nitrogen-containing organic compounds.

Abstract: A water treatment system is provided with a nitrogen-containing organic compound oxidizing device that treats the first-stage treatment water after filtration and removal of cation ions. An oxidant-containing water stream and an inorganic bromide-containing water stream are respectively added into a pipeline that conducts the first-stage treatment water and then pass through an in-pipe mixer and a mixing unit, whereby to oxidize the nitrogen-containing organic compounds in the first-stage treatment water and then form the second-stage treatment water for output.

Abstract: A manufacturing system of an electronic-grade ammonia solution comprises: a mixing tank to mix an unsaturated ammonia aqueous solution and alkali to obtain a mixing solution; a stripping unit, disposes downstream the mixing tank and comprises a heat exchanger to heat the mixing solution, and a stripping column to mix a nitrogen gas and the heated mixing solution to obtain a mixing gas; a first absorption unit, disposes downstream the stripping unit and comprises a first condensation unit to cool down the mixing gas, and a first absorption column to mix a saturated ammonia aqueous solution and the cooled mixing gas to obtain a purge gas; and a second absorption unit, disposes downstream the first absorption unit and comprises a second condensation unit to cool down a DI water, and a second absorption column to mix the cooled DI water and the purge gas to obtain electronic-grade ammonia solution.

Abstract: A manufacturing system of an electronic-grade ammonia solution comprises: a mixing tank to mix an unsaturated ammonia aqueous solution and alkali to obtain a mixing solution; a stripping unit, disposes downstream the mixing tank and comprises a heat exchanger to heat the mixing solution, and a stripping column to mix a nitrogen gas and the heated mixing solution to obtain a mixing gas; a first absorption unit, disposes downstream the stripping unit and comprises a first condensation unit to cool down the mixing gas, and a first absorption column to mix a saturated ammonia aqueous solution and the cooled mixing gas to obtain a purge gas; and a second absorption unit, disposes downstream the first absorption unit and comprises a second condensation unit to cool down a DI water, and a second absorption column to mix the cooled DI water and the purge gas to obtain electronic-grade ammonia solution.