2992results about "Alkali metal chlorides" patented technology

A process and system for purifying water is disclosed. For example, in one embodiment, the process may be used to remove a divalent salt, such as calcium sulfate, from a water source in order to prevent the divalent salt from precipitating during the process. The water source, for instance, may be fed to an ion separating device, such as an electrodialysis device. In the electrodialysis device, an ion exchange takes place between the divalent salt and another salt, such as a monovalent salt to produce two concentrated salt streams that contain salts having greater solubility in water than the divalent salt. In one embodiment, the two salt streams that are produced may then be combined to precipitate the divalent salt in a controlled manner. During the process, various other components contained within the water feed stream may also be removed from the stream and converted into useful products. In one particular embodiment, the process is configured to receive a byproduct stream from a reverse osmosis process.

This invention discloses improvements on previous inventions for catalytic conversion of coal and steam to methane. The disclosed improvements permit conversion of petroleum residua or heavy crude petroleum to methane and carbon dioxide such that nearly all of the heating value of the converted hydrocarbons is recovered as heating value of the product methane. The liquid feed is distributed over a fluidized solid particulate catalyst containing alkali metal and carbon as petroleum coke at elevated temperature and pressure from the lower stage and transported to the upper stage of a two-stage reactor. Particulate solids containing carbon and alkali metal are circulated between the two stages. Superheated steam and recycled hydrogen and carbon monoxide are fed to the lower stage, fluidizing the particulate solids and gasifying some of the carbon. The gas phase from the lower stage passes through the upper stage, completing the reaction of the gas phase.

The invention discloses a method and device for utilizing sewage containing ammonia and sodium. The method comprises the steps of deamination reaction, denitrification reaction, gas-liquid separation, triple-effect multistage evaporation, evaprative crystallization and freezing crystallization, electrodialysis and sodium filteration membrane, and concentration of reverse osmosis membrane, so that distilled water and membrane deion pure water are recovered, and the resource utilization of sole sodium chloride and sodium sulfate is realized.

A desalination plant for treating a sea water or brackish water feed is provided. The desalination plant includes a first treatment section to effectively remove scaling species, the first treatment section including nanofiltration section, the nanofiltration section including at least two stages and at least two passes; and a reverse osmosis section that operates at high recovery to produce a purified permeate stream and a selectively NaCl salt-enriched reject stream as a saline output.

Methods for the production of shaped nanoscale-to-microscale structures, wherein a nanoscale-to-microscale template is provided having an original chemical composition and an original shape, and the nanoscale-to-microscale template subjected to a chemical reaction, so as to partially or completely convert the nanoscale-to-microscale template into the shaped nanoscale-to-microscale structure having a chemical composition different than the original chemical composition and having substantially the same shape as the original shape, being a scaled version of the original shape. The shaped nanoscale-to-microscale structure formed comprises an element (such as silicon), a metallic alloy (such as a silicon alloy), or a non-oxide compound (such as silicon carbide or silicon nitride).

In the methods for treatment of caustic effluents described in the specification, a spent caustic refinery effluent is supplied to a submerged combustion gas evaporator in which hot combustion gas containing carbon dioxide is injected into the caustic liquid to concentrate the liquid and convert a hydroxide constituent to a carbonate. Where the caustic effluent is from a petroleum refinery, oil in the waste liquid is separated from the aqueous constituent before, during or after concentration.

The invention discloses an industrial application of an MVR (mechanical vapor recompression) crystallizing evaporator technology in the production of sodium sulfate and sodium chloride in Huaian, Jiangsu, and relates to an improvement of a salt and sodium sulfate coproduction evaporation technology, belonging to the technical field of chemical three-waste treatment and utilization, and in particular to an application of an MVR crystallizing evaporator in a sodium sulfate and sodium chloride separation technology. The application is mainly technically characterized in that sodium sulfate liquid is concentrated by the MVR crystallizing evaporator, the sodium sulfate is produced at high temperature, and the sodium chloride is produced at low temperature. According to the invention, the mechanical re-compressed vapor is evaporated, concentrated and crystallized at 90-100 DEG C to obtain sodium sulfate, and the re-compressed vapor at a low temperature of 55 DEG C is concentrated and crystallized to obtain sodium chloride. According to the invention, the application of the MVR technology to the concentration of sodium sulfate liquid is realized, the sodium sulfate is produced at high temperature, and sodium chloride is produced at low temperature. The application disclosed by the invention is an environmental protection project which saves energy, reduces emission and avoids waste gas, waste water and waste residue.

The invention relates to a process method for recovering ammonium chloride and sodium chloride from waste water containing the ammonium chloride and the sodium chloride, which produces the ammonium chloride and the sodium chloride by using mother solution which is generated in a process for producing sodium bicarbonate by natural bittern double decomposition reaction and contains the ammonium chloride and the sodium chloride as raw materials. The method adopts ammonium still, evaporation, crystallization and separation process to treat, wherein the evaporation adopts multiple-effect, a heat pump and a vacuum evaporation process, and selects a falling film evaporator and a forced circulation type evaporator to perform triple-effect mixed-flow procedure, so that sodium chloride is crystallized and separated in the evaporation; and the ammonium chloride is crystallized and separated by cooling after the evaporation. The method effectively reduces the operation temperature of the equipment, can repeatedly use secondary steam and condensed water, reduces erosion of the ammonium chloride solution to the equipment, saves the energy, reduces the cost, improves the production efficiency, and reduces environmental pollution.

The invention provides a treating method for sewage containing sodium sulfate and sodium chloride. The method comprises a step of preparing sewage to be treated as raw water and a step of carrying out nanofiltration on the raw water. The method may also comprise a step of carrying out evaporative crystallization on concentrated water obtained after nanofiltration so as to obtain anhydrous sodium sulfate. The method may further comprise a step of carrying out reverse osmosis treatment on yielded water obtained after nanofiltration and using yielded water obtained after reverse osmosis treatment as diluting water in nanofiltration of the raw water. The method may also comprise a step of carrying out secondary nanofiltration on yielded water obtained after nanofiltration so as to obtain concentrated water and yielded water obtained after secondary nanofiltration, a step of carrying out reverse osmosis treatment on yielded water obtained after secondary nanofiltration and carrying out evaporative crystallization on concentrated water obtained after reverse osmosis treatment so as to obtain sodium chloride, a step of using yielded water obtained after reverse osmosis treatment as diluting water in nanofiltration of the raw water, and a step of carrying out evaporative crystallization on concentrated water obtained after secondary nanofiltration in the sequence of concentration so as to obtain anhydrous sodium sulfate or subjecting the concentrated water together with next batch of raw water to nanofiltration again . The method provided in the invention can be used for separating and purifying anhydrous sodium sulfate and sodium chloride and for purifying sewage.

The invention discloses a wastewater evaporation concentration process and a wastewater evaporation concentration device system. The process comprises the following steps of: delivering softened wastewater to be treated to a mechanical vapor recompression (MVR) system to perform evaporation and concentration, compressing the generated secondary steam and then delivering the compressed steam to an evaporator to recycle, delivering the concentrate to a triple-effect mixed flow forced circulating evaporation crystallization system to perform evaporation and crystallization, performing solid-liquid centrifugal separation on the crystallized concentrate and crystal grains, returning the separated mother solution to a stock solution tank or continuously performing evaporation and crystallization, and reclaiming the separated crystal, wherein the secondary steam generated by evaporation and crystallization is recycled for the evaporation crystallization system. After the wastewater is evaporated and concentrated by adopting the process of mechanical vapor recompression circulating evaporation and triple-effect mixed flow forced circulating evaporation crystallization, the wastewater does not need to be discharged to the ground water area, and the wastewater is discharged in a form of steam or closed and embedded in a form of sludge or the like, so the purpose of zero discharge of the wastewater can be fulfilled; and the process system has high heat efficiency, low energy consumption, energy conservation, great reduction in running cost, low temperature difference, low corrosion, difficult scale formation and long equipment service life.

The invention provides a brine purification technical method which comprises that: a first step is that limewater is added into brine so that reaction happens to calcium hydroxide in the limewater and magnesian ion in the brine to generate magnesium hydrate sedimentation, the magnesian ion in the brine is removed, excessive calcium hydroxide is used for causticizing the sodium sulfate in the brine into sodium hydroxide; a second step is that flue gas is put into the brine after the magnesian ion is removed for carrying out reaction between carbon dioxide in the flue gas and the sodium hydroxide causticized in the brine to generate sodium carbonate which reacts with calcium ion in the brine to generate calcium carbonate sedimentation, the calcium ion in the brine is removed; a third step is that slurry produced in the first step and the second step is collected; and a fourth step is that refined brine after being treated by the first step and the second step is recycled. The technical method can reduce the pollution to environment, can save energy, and can reduce the consumption of raw brine and the purification cost of the brine at the same time, thereby conforming to the requirements of the strategy of sustainable development.

Processes comprising: (a) reacting phosgene and a monohydroxyl aryl compound in the presence of a suitable catalyst to form a diaryl carbonate and a solution comprising an alkali chloride; (b) separating the diaryl carbonate from the solution; (c) adjusting the pH of the solution to a value of less than or equal to 8 to form a pH-adjusted solution; (d) treating the pH-adjusted solution with an adsorbent to form a treated solution; (e) subjecting at least a portion of the treated solution to electrochemical oxidation to form chlorine and an alkali hydroxide solution; and (f) recycling at least a portion of one or both of the chlorine and the alkali hydroxide solution.

The invention relates to a chemical industrial waste salt refining process which comprises the following steps: pretreating high salt wastewater generated in the production process of aminobenzene ether and p-nitrophenol so as to adjust the pH value, adsorbing by using activated carbon, kieselguhr or macroporous resin, removing organisms and organic salts in the wastewater, reducing the COD of the wastewater, neutralizing the high salt wastewater, performing multi-effect evaporation or mechanical recompression so as to evaporate and crystallize, and centrifuging a solid salt; performing high-temperature calcination on the centrifuged solid salt in a rotary kiln or a tunnel kiln, thereby decomposing and oxidizing the organisms at a high temperature, further thoroughly combusting the tail gas generated through calcination in a heat accumulation type tail gas combustion furnace, preheating and recycling the tail gas, performing spraying absorption, dissolving the calcinated salt with water so as to prepare a saturated solution, filtering by using a precise filter, directly supplying the filtrate to ionic membrane caustic soda for use, or performing multi-effect evaporation or mechanical recompression on the filtered saturated salt water so as to evaporate, crystallize and purify, and performing centrifugation, thereby obtaining high-quality solid sodium chloride.

The invention relates to a crystallization treatment method and device of high salt wastewater and belongs to the technical field of water treatment. The method is characterized in that after sodium sulfate concentrated water is treated by a freezing crystallization system, generated mother liquor A enters into an MVR system for evaporative crystallization; after sodium chloride concentrated water is treated by the MVR system, generated mother liquor B enters into a freezing crystallization system for freezing crystallization, and the mother liquor can be treated in a circulation overlapping manner; a drain outlet of the MVR system of the device is connected with a liquid inlet of a crystallization tank in the freezing crystallization system through a pipeline and the drain outlet of the freezing crystallization system is connected with a liquid inlet pipe of the MVR evaporative crystallization system. The method has the advantages that the mother liquor is treated by a freezing crystallization technology and an MVR evaporation crystallization technology in a circulation overlapping manner, so that the problems of zero emission and resource utilization are solved, and therefore, the energy consumption is effectively reduced and the operating cost is lowered.

Zero discharge processing methods for the treatment of agricultural drainage water (ADW) are disclosed. The disclosed methods are capable of meeting the three critical issues in treating ADW: (1) selective removal of sulfate scale-prone species and toxic species; (2) production of usable water that at least meets irrigation water quality; and (3) recovery of sodium sulfate and sodium chloride as valuable commodities.

The invention relates to a process for production of diaryl carbonate combined with the electrolysis of the resultant alkali metal chloride-containing process wastewater. The process according to the invention makes possible, inter alia, improved utilization in electrolysis of the alkali metal chloride-containing solution obtained in the production of diaryl carbonate.

An automated salt dispensing system operating in conjunction with an at least one salt chlorine generator with a controller, an at least one water supply pipe with an at least one inflow and an at least one outflow, an at least one water diversion pipe, an at least one actuator in communication with the controller and controlling a control valve, said control valve being coupled to said at least one water supply and said at least one diversion pipe and diverting water into said water diversion pipe. The invention further includes an at least one brine solution holding tank; and an at least one pressure differential device, wherein the at least one brine solution holding tank is coupled to said at least one pressure differential device and the controller signals the actuator and the control valve diverts water from the water supply pipe into the water diversion pipe and the at least pressure differential device draws brine solution from an at least one brine solution holding tank into the water supply line.