WO2023140055A1 - 二酸化炭素の固定化方法 - Google Patents

二酸化炭素の固定化方法 Download PDF

Info

Publication number
WO2023140055A1
WO2023140055A1 PCT/JP2022/047822 JP2022047822W WO2023140055A1 WO 2023140055 A1 WO2023140055 A1 WO 2023140055A1 JP 2022047822 W JP2022047822 W JP 2022047822W WO 2023140055 A1 WO2023140055 A1 WO 2023140055A1
Authority
WO
WIPO (PCT)
Prior art keywords
concentrated liquid
carbon dioxide
earth metal
alkaline earth
membrane
Prior art date
Application number
PCT/JP2022/047822
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
隆雄 中垣
コーリ アダム マイヤズ
翔 藤本
良彦 加藤
悟 平野
基頼 早水
慶明 三保
Original Assignee
学校法人早稲田大学
日揮グローバル株式会社
株式会社ササクラ
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 学校法人早稲田大学, 日揮グローバル株式会社, 株式会社ササクラ filed Critical 学校法人早稲田大学
Priority to JP2023575161A priority Critical patent/JPWO2023140055A1/ja
Publication of WO2023140055A1 publication Critical patent/WO2023140055A1/ja

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/62—Carbon oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/58—Multistep processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/02—Treatment of water, waste water, or sewage by heating
    • C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/469—Treatment of water, waste water, or sewage by electrochemical methods by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis

Definitions

  • the present invention relates to a method for immobilizing carbon dioxide on alkaline earth metals.
  • CO 2 fixation method As global warming becomes more serious, it is required to suppress temperature rise, and as an evaluation model for this, the goal is to reduce anthropogenic carbon dioxide (CO 2 ) emissions to zero.
  • a CO2 fixation method is mentioned as a means to achieve the above-mentioned goal.
  • As an effective CO 2 fixation method there is a method of using alkaline earth metals such as Mg and Ca to bind and fix CO 2 with these alkaline earth metals.
  • Mg and Ca are also contained in seawater and waste brine from seawater desalination plants. For example, CO 2 fixation methods using seawater have been proposed (see, for example, Patent Documents 1 and 2).
  • the present invention provides a method for fixing carbon dioxide to alkaline earth metals that enhances the ability to reduce carbon dioxide while considering the amount of carbon dioxide emissions.
  • the object of the present invention is to provide a first step of passing seawater or brackish water through a nanofiltration membrane to generate a first concentrated liquid that is concentrated without permeating through the nanofiltration membrane, a second step of adding an alkali to the first concentrated liquid generated in the first step, reacting carbon dioxide with the alkaline earth metal contained in the first concentrated liquid to fix it, and depositing alkaline earth metal carbonate crystals, and depositing alkaline earth metal carbonate crystals deposited in the second step.
  • the first step includes a concentration step of concentrating the NF membrane permeate that has passed through the nanofiltration membrane to generate a second concentrate, and an electrodialysis step of separating an acid solution and an alkali solution by electrodialyzing the second concentrate, and the second step is achieved by a carbon dioxide immobilization method of adding the alkali solution obtained in the electrodialysis step to the first concentrate.
  • the concentration step preferably includes a step of concentrating the NF membrane permeate liquid with a reverse osmosis membrane.
  • the first step preferably further comprises an alkaline earth metal removal step of removing alkaline earth metals contained in the second concentrated liquid with a chelate resin or an ion exchange resin before the electrodialysis step.
  • the first step preferably further includes a resin regeneration step of regenerating the chelate resin or ion exchange resin using the acid solution obtained in the electrodialysis step.
  • the acid solution in which the chelate resin or ion exchange resin is regenerated is combined with the first concentrated liquid.
  • the first step preferably further includes an evaporative crystallization step of precipitating calcium sulfate crystals by evaporative crystallization of the first concentrated liquid, and a solid-liquid separation step of solid-liquid separating and recovering the calcium sulfate crystals precipitated by the evaporative crystallization step from the first concentrated liquid.
  • the object of the present invention includes a first step of passing seawater or brackish water through a nanofiltration membrane to generate a first concentrated liquid that is concentrated without passing through the nanofiltration membrane, a second step of adding an alkali to the first concentrated liquid generated in the first step, reacting carbon dioxide with the alkaline earth metal contained in the first concentrated liquid to immobilize it, and precipitating alkaline earth metal carbonate crystals, and the alkaline earth metal carbonate crystals deposited in the second step.
  • a third step of solid-liquid separation and recovery from the first concentrated liquid includes an electrodialysis step of separating an acid solution and an alkaline solution by electrodialyzing the NF membrane permeate that has passed through the nanofiltration membrane, and the second step is achieved by a carbon dioxide immobilization method in which the alkaline solution obtained in the electrodialysis step is added to the first concentrated liquid.
  • FIG. 1 is a processing flow diagram for explaining a carbon dioxide fixation method according to a first embodiment of the present invention
  • FIG. 3 is a diagram showing a modification of one step in the processing flow shown in FIG. 1
  • FIG. 2 is a diagram showing an example of changes in the amount of various ions in the processing flow shown in FIG. 1
  • FIG. 8 is a diagram showing a modification of another step in the processing flow shown in FIG. 1
  • FIG. 5 is a processing flow diagram for explaining a carbon dioxide fixation method according to a second embodiment of the present invention.
  • the carbon dioxide fixation method of the present invention provides a method for fixing carbon dioxide to alkaline earth metals contained in seawater or brackish water.
  • alkaline earth metal means a broad range including Mg and Be, which are elements of Group 2 of the periodic table, in addition to Ca, Sr, Ba and Ra.
  • Mg and Be are elements of Group 2 of the periodic table, in addition to Ca, Sr, Ba and Ra.
  • Seawater or brackish water is an aqueous solution containing alkaline earth metal ions such as magnesium ions (Mg 2+ ) and calcium ions (Ca 2+ ).
  • Seawater or brackish water usually contains at least one kind of crystalline ions selected from calcium sulfate, sodium chloride, potassium chloride and sodium sulfate, in addition to alkaline earth metal ions.
  • seawater or brine usually contains at least one ion selected from chloride ions (Cl ⁇ ), sulfate ions (SO 4 2 ⁇ ), sodium ions (Na + ), and potassium (K + ).
  • brackish water one obtained from at least one selected from seawater, salt lakes, and industrial wastewater can be used.
  • seawater, salt lakes, and industrial wastewater river water, rainwater, treated sewage water, produced water from oil fields and gas fields, and the like can also be used as long as they contain alkaline earth metals.
  • brackish water includes water production using salt lakes and the like, waste liquid brine discharged from desalination and salt making processes, recovery of valuables using seawater and salt lakes, and industrial wastewater from chemical factories and the like.
  • the brackish water is preferably at least one kind selected from brackish water obtained from a fresh water generator using seawater, brackish water obtained from a process of making salt from seawater, and brackish water obtained from a process of recovering lithium from a salt lake.
  • FIG. 1 is a processing flow diagram for explaining a carbon dioxide fixation method according to a first embodiment of the present invention.
  • seawater is treated, but the same treatment can be applied to brackish water.
  • FIG. 1 is a processing flow diagram for explaining a carbon dioxide fixation method according to a first embodiment of the present invention.
  • seawater is treated, but the same treatment can be applied to brackish water.
  • the method for immobilizing carbon dioxide of the first embodiment includes a first step S1 of generating a first concentrated liquid that is an NF membrane concentrated liquid that is concentrated without permeating the NF membrane by passing seawater through a nanofiltration membrane (NF membrane), and adding an alkali to the first concentrated liquid generated in the first step S1 to react carbon dioxide with the alkaline earth metal contained in the first concentrated liquid to immobilize and precipitate alkaline earth metal carbonate crystals. It comprises a second step S2 and a third step S3 of recovering the alkaline earth metal carbonate crystals deposited in the second step S2 by solid-liquid separation from the first concentrated liquid.
  • NF membrane nanofiltration membrane
  • ⁇ S1 First step>
  • the seawater is supplied to the NF membrane unit by a medium pressure pump or the like and passed through the NF membrane, thereby generating an NF membrane permeated liquid that has passed through the NF membrane and a first concentrated liquid that is concentrated without passing through the NF membrane.
  • the pretreatment step S0 can perform the same pretreatment as in the conventional seawater desalination treatment using a reverse osmosis membrane, and can be exemplified by filtration, coagulation, sedimentation and the like.
  • the first step S1 can also be performed by multiple stages (two stages in FIG.
  • the permeated liquid of the NF membrane unit 101 in the former stage may be introduced into the NF membrane unit 102 in the latter stage, and the concentrated liquids of the NF membrane units 101 and 102 in each stage may be combined to generate the NF membrane concentrate.
  • FIG. 3 shows an example of the amounts (kg/h) of various ions contained in seawater, NF membrane permeate and NF membrane concentrate (first concentrate) when seawater is supplied at a flow rate of 100 m 3 /h.
  • the first step S1 includes a concentration step S11 for concentrating the NF membrane permeate to generate a second concentrate, an alkaline earth metal removal step S12 for removing the alkaline earth metal contained in the generated second concentrate, and an electrodialysis step S13 for electrodialyzing the second concentrate from which the alkaline earth metal has been removed.
  • the NF membrane-permeated liquid is supplied to a reverse osmosis membrane (RO membrane) unit by a high-pressure pump or the like and is passed through the RO membrane, thereby concentrating without passing through the RO membrane. Since the NF membrane permeated liquid contains almost no SO 4 2 ⁇ , the NF membrane permeated liquid can be concentrated to a high concentration by low-energy membrane treatment using an RO membrane.
  • the concentration step S11 preferably includes a membrane concentration step using an RO membrane as in the present embodiment, but is not limited to this. For example, it may include an evaporation concentration step of evaporating and concentrating the NF membrane permeate liquid.
  • the concentration step S11 includes a membrane concentration step using an RO membrane
  • the treatment is not limited to the treatment using only the RO membrane, and may be combined with other treatments using a semipermeable membrane.
  • the concentration step S11 includes an RO membrane concentration step S111 in which the NF membrane permeated liquid is concentrated with an RO membrane to generate an RO membrane concentrate, and a composite membrane treatment step S112 in which the RO membrane concentrate is supplied to the high pressure chamber of the semipermeable membrane unit separated by the semipermeable membrane, and the RO membrane concentrate is further concentrated by utilizing the pressure difference between the recovered liquid passing through the low pressure chamber.
  • the recovered liquid supplied to the low-pressure chamber can use a part of the RO membrane concentrated liquid that has passed through the high-pressure chamber, and the recovered liquid that has passed through the low-pressure chamber can be combined with the NF membrane permeated liquid before the RO membrane concentration step S111.
  • the membrane-treated permeate that has passed through the RO membrane in the concentration step S11 can be recovered, for example, as manufactured water.
  • the concentration step S11 may be performed only on part of the NF membrane permeated liquid produced in the first step S1, and the remaining NF membrane permeated liquid not used in the concentration step S11 may be used in another step such as a desalination process.
  • the NF membrane permeated liquid that is not used in another process may be discharged into the ocean or the like.
  • the alkaline earth metal removal step S12 can be performed, for example, by passing the second concentrated liquid through a column filled with a chelate resin.
  • a chelate resin it is preferable to use one capable of selectively capturing alkaline earth metal ions such as magnesium ions and calcium ions. Examples thereof include iminodiacetic acid type and aminophosphate type.
  • the alkaline earth metal removing step S12 is not limited to the step of removing the alkaline earth metal contained in the second concentrated liquid with a chelate resin, and may be a step of removing with an ion exchange resin.
  • the alkaline earth metal ion concentration of the second concentrated liquid produced in the concentration step S11 is high (for example, about several hundred ppm)
  • a step of adding sodium hydroxide, sodium carbonate, or the like to the second concentrated liquid to crystallize and remove alkaline earth metal ions such as magnesium ions and calcium ions may be provided before the alkaline earth metal removal step S12.
  • the alkaline earth metal ion concentration of the second concentrated liquid generated in the concentration step S11 is low, the alkaline earth metal removal step S12 may be omitted.
  • the electrodialysis step S13 can use, for example, a bipolar membrane electrodialysis device.
  • the second concentrated liquid that has undergone the alkaline earth metal removal step S12 is a high-purity NaCl solution in which the concentration of impurities such as magnesium and calcium is sufficiently reduced (for example, 1 ppm or less), and is separated into an HCl solution and a NaOH solution by the electrodialysis step S13.
  • Electrodialysis preferably utilizes renewable energy, such as solar energy, and can reduce CO2 emissions throughout the process.
  • the NaOH solution obtained in the electrodialysis step S13 can be suitably used as the alkali added in the second step S2.
  • part of the seawater that has undergone the pretreatment step S0 is bypassed without passing through the NF membrane so that the alkaline solution produced in the electrodialysis step S13 is only the amount required in the second step S2.
  • the seawater bypassing the NF membrane can be used for immobilization of carbon dioxide in the second step S2 after joining the first concentrated liquid.
  • the first step S1 further includes an evaporation crystallization step S14 and a solid-liquid separation step S15.
  • evaporative crystallization step S14 calcium sulfate crystals are precipitated by evaporating and concentrating the first concentrated liquid in the crystallizer before performing the second step S2.
  • this seed crystal for example, calcium sulfate crystals recovered in the solid-liquid separation step S15 described later can be used.
  • the distilled water produced in the evaporative crystallization step S14 can be recovered, for example, together with the membrane treatment permeate produced in the concentration step S11 as production water, and can also be used as washing water in the third step S3 described later.
  • an acid to the first concentrated liquid before performing the evaporation and crystallization step S14 to adjust the pH.
  • this acid for example, the HCl solution obtained in the electrodialysis step S13 can be used.
  • the calcium sulfate crystals precipitated in the evaporative crystallization step S14 are recovered by solid-liquid separation from the first concentrated liquid using a solid-liquid separation device.
  • the recovered calcium sulfate crystals can be used, for example, as gypsum.
  • the first step S1 further includes a resin regeneration step S16 for regenerating the chelate resin or ion-exchange resin by passing a regeneration liquid through the chelate resin or ion-exchange resin that captured the alkaline-earth metal in the alkaline-earth metal removal step S12 to desorb the alkaline earth metal.
  • a regeneration liquid an acid solution is preferably used, and for example, the HCl solution obtained in the electrodialysis step S13 can be preferably used.
  • Alkaline earth metals to be recovered, such as magnesium, are contained not only in the first concentrated liquid but also in the NF membrane permeated liquid.
  • the acid solution obtained by regenerating the chelate resin or the ion exchange resin is preferably combined with the first concentrated liquid before the evaporation and crystallization step S14 is performed.
  • the recovery rate of the alkaline earth metal required for fixing carbon dioxide in the second step S2 can be increased.
  • a part of the HCl solution obtained in the electrodialysis step S13 may be combined with the seawater before performing the first step S1. Thereby, fouling of the film surfaces of the NF film and the RO film in the first step S1 can be suppressed.
  • the seawater to which the HCl solution is combined may be seawater before performing the pretreatment step S0, or seawater after performing the pretreatment step S0.
  • ⁇ S2 Second step>
  • the pH of the first concentrated liquid is adjusted to the alkaline side (for example, pH 9 to 10) and stored in a storage tank.
  • a gas containing carbon dioxide By blowing a gas containing carbon dioxide into the first concentrated liquid and bringing it into gas-liquid contact by bubbling, the alkaline earth metal contained in the first concentrated liquid is reacted with carbon dioxide and immobilized.
  • the gas containing carbon dioxide may be the atmosphere, or may be exhaust gas from various combustion devices.
  • the concentration of carbon dioxide contained in the gas is not limited, but for example, the concentration of carbon dioxide contained in the gas is from the atmosphere to about 100% by volume.
  • the addition of the alkali to the first concentrated liquid may be performed before as well as during the bubbling of the carbon dioxide-containing gas.
  • fine bubbles of carbon dioxide fine bubbles such as microbubbles and ultrafine bubbles
  • the method of bringing the first concentrated liquid and carbon dioxide into gas-liquid contact is, in addition to the method of blowing CO2 gas into the first concentrated liquid, in a single-stage or multi-stage desulfurization tower or degassing tower, etc. It may be a method of spraying the first concentrated liquid into the CO2 gas with a spray nozzle or tray, etc., and various known gas-liquid contactors can be used in consideration of the reaction rate, reaction amount, CO2 concentration in gas such as exhaust gas, etc.
  • the alkali added to the first concentrated liquid in the second step S2 is preferably the NaOH solution obtained in the electrodialysis step S13 as described above, and an increase in CO 2 emissions accompanying the separate production of alkali can be suppressed.
  • an alkali different from the alkali obtained in the electrodialysis step S13 may be used, or the alkali obtained in the electrodialysis step S13 and another alkali may be used in combination.
  • the second step S2 has the following merits. First, since the amount of the first concentrated liquid in which the second step S2 is performed can be reduced, the amount of alkali (NaOH) to be added can be reduced, and the power consumption of the electrodialysis step S13 can be suppressed. In addition, since the concentration of the alkaline earth metal in the first concentrated liquid in which the second step S2 is performed increases, the reaction efficiency of carbon dioxide increases, so the amount of bubbling of carbon dioxide is reduced and the power consumption required for bubbling can be suppressed.
  • NaOH alkali
  • the evaporative crystallization step S14 and the solid-liquid separation step S15 are not essential in the present invention, and the configuration may be such that they are not provided.
  • ⁇ S3 Third step>
  • the first concentrated liquid that has undergone the second step S2 becomes a slurry liquid in which alkaline earth metal carbonate crystals containing a small amount of CaCO3 and the like in addition to MgCO3 are precipitated by the reaction between the alkaline earth metal and carbon dioxide.
  • the alkaline earth metal carbonate crystals contained in the slurry liquid are recovered by solid-liquid separation using a solid-liquid separator such as a centrifugal separator.
  • the third step S3 comprises a neutralization step S31 of neutralizing the filtrate after recovering the alkaline earth metal carbonate crystals from the first concentrated liquid. Since the filtrate of the first concentrated liquid usually has a pH of 9 or higher due to the addition of alkali, by neutralizing it by adding an acid (for example, pH 7 to 8), it can be discharged as it is to the outside of the system such as the ocean. It is preferable to use the HCl solution obtained in the electrodialysis step S13 as the acid added to the filtrate, and it is possible to suppress an increase in CO 2 emissions accompanying the separate production of the acid.
  • the third step S3 further includes a water washing step S32 of washing the collected alkaline earth metal carbonate crystals with washing water to dissolve and remove Na + , K + etc. adhering to the alkaline earth metal carbonate crystals in the washing water.
  • the washing water used in the water washing step S32 preferably contains the distilled water produced in the evaporative crystallization step S14. For example, by combining the distilled water with the NF membrane permeated liquid and using it as washing water, it is possible to suppress an increase in CO 2 emissions accompanying the separate production of washing water.
  • Alkaline earth metal carbonate crystals such as MgCO 3 after washing can be suitably used as building materials such as concrete and cement. Therefore, the present invention can also provide a method for producing an alkaline earth metal carbonate salt using the carbon dioxide fixation method.
  • the carbon dioxide fixation method of this embodiment can easily and efficiently fix carbon dioxide to the alkaline earth metals contained in seawater or brackish water, and the alkali, acid, distilled water, etc. generated in each step can be used to complete carbon dioxide fixation in the system, so it is possible to increase the carbon dioxide reduction capacity while considering the amount of carbon dioxide emitted in the entire process.
  • FIG. 5 is a processing flow diagram for explaining the carbon dioxide immobilization method according to the second embodiment of the present invention.
  • the carbon dioxide fixation method of the second embodiment shown in FIG. 5 includes a first step S1 of passing seawater through an NF membrane to generate a first concentrated liquid that is concentrated without permeating the NF membrane, a second step S2 of adding an alkali to the first concentrated liquid generated in the first step S1, reacting carbon dioxide with the alkaline earth metal contained in the first concentrated liquid, and immobilizing it to precipitate alkaline earth metal carbonate crystals. and a third step S3 of recovering the alkaline earth metal carbonate crystals deposited in the second step S2 by solid-liquid separation from the first concentrated liquid.
  • seawater is also treated, but brackish water can also be treated in the same manner, and can be suitably used particularly when the Ca or Mg content is high.
  • brackish water can also be treated in the same manner, and can be suitably used particularly when the Ca or Mg content is high.
  • the first concentrated liquid in which the evaporative crystallization step S14 is performed contains Ca 2+ , Na + , K + and the like, but since calcium sulfate crystals have reverse solubility in which the solubility decreases as the temperature rises, concentration is performed to a concentration ratio at which NaCl and KCl are not precipitated while maintaining the operating temperature of the evaporative concentration so that Ca 2+ is precipitated but Na + and K + are not precipitated.
  • the operating temperature of the evaporative concentration is preferably 70 to 90°C, and is set to 80°C, for example.
  • the precipitated calcium sulfate crystals can be recovered in the solid-liquid separation step S15 as in the first embodiment. Distilled water produced in the evaporative crystallization step S14 can be used as manufacturing water and washing water, as in the first embodiment.
  • alkaline earth metal carbonate crystals such as MgCO 3 precipitated in the second step S2 are solid-liquid separated from the first concentrated liquid by a solid-liquid separator and recovered.
  • the recovered alkaline earth metal carbonate crystals are washed with washing water in the washing step S32 as in the first embodiment.
  • the washing water used in the water washing step S32 can be, for example, the distilled water produced in the concentrated crystallization step S331, which will be described later, other than the distilled water produced in the evaporative crystallization step S14.
  • the third step S3 includes a crystal recovery step S33 of precipitating and recovering crystals of sodium chloride, potassium chloride and sodium sulfate from the filtrate after recovering the alkaline earth metal carbonate crystals from the first concentrated liquid.
  • the filtrate in which the crystal recovery step S33 is performed is preferably only a part of the filtrate obtained by solid-liquid separation of the alkaline earth metal carbonate crystals, and the remainder of the filtrate obtained by solid-liquid separation is preferably discharged out of the system through the neutralization step S31 in order to suppress an increase in impurity concentration.
  • the washing water used to wash the alkaline earth metal carbonate crystals in the washing step S32 may be added to the filtrate in which the crystal collecting step S33 is performed.
  • the crystal recovery step S33 includes a concentration crystallization step S331 in which sodium chloride crystals are precipitated and recovered by evaporating and concentrating the filtrate, and a cooling crystallization step S332 in which the precipitated crystals are recovered by cooling and crystallizing the filtrate.
  • the filtrate is supplied to a crystallizer and heated to evaporate and concentrate to precipitate crystals mainly composed of sodium chloride (NaCl), and then the sodium chloride crystals are separated by a solid-liquid separation device.
  • the operating temperature of the evaporative concentration is preferably 60 to 80°C, and is set to 70°C, for example.
  • the filtrate that has undergone the concentrated crystallization step S331 is supplied to a cooling crystallizer and cooled to a predetermined cooling crystallization temperature while stirring, thereby precipitating crystals of the target impurity, and then the crystals are separated by a solid-liquid separator.
  • the cooling crystallization step S332 includes a first cooling crystallization step S3321 of cooling and crystallizing the first concentrated liquid to recover crystals containing potassium chloride (KCl) as a main component, and cooling and crystallization of the filtrate that has passed through the first cooling crystallization step S3321 at a temperature lower than the cooling crystallization temperature of the first cooling crystallization step S3321 to recover sodium sulfate crystals (Na 2 SO 4 .10H 2 O) precipitated. and a second cooling crystallization step S3322.
  • KCl potassium chloride
  • the cooling crystallization temperature in the first cooling crystallization step S3321 is a temperature at which crystals mainly composed of KCl are precipitated, but crystals of Na 2 SO 4 .10H 2 O are not precipitated, and is preferably 33 to 40°C, and is set to, for example, 36°C.
  • the cooling crystallization temperature in the second cooling crystallization step S3322 is the temperature at which Na 2 SO 4.10H 2 O crystals precipitate, and is set to 0 to 10° C., for example.
  • the filtrate that has passed through the crystal recovery step S33 is alkaline, and can be partially combined with the first concentrated liquid before the evaporation and crystallization step S14 is performed.
  • the remainder of the filtrate that has passed through the crystal recovery step S33 can be neutralized with an acid such as the HCl solution obtained in the electrodialysis step S13 in a neutralization step S34 and discharged out of the system.
  • the crystal recovery step S33 it is not necessary to perform all of the concentration crystallization step S331, the first cooling crystallization step S3321, and the second cooling crystallization step S3322, and only the necessary steps may be appropriately selected according to the components of the seawater or brackish water to be treated so that at least one crystal selected from sodium chloride, potassium chloride, and sodium sulfate can be precipitated and recovered from the filtrate.
  • the device for executing the processing flow according to each of the above embodiments can be newly configured, but for example, it is also possible to retrofit (retrofit) a device (for example, an NF membrane unit, etc.) for performing necessary processing to an existing seawater desalination device equipped with a pretreatment device and an RO membrane unit.
  • a device for example, an NF membrane unit, etc.
  • the first step S1 may be configured without the concentration step S11 of concentrating the NF membrane-permeated liquid to generate the second concentrated liquid. That is, the first step S1 may include an alkaline earth metal removal step S12 in which the alkaline earth metal contained in the NF membrane permeated liquid is removed by a chelate resin or an ion exchange resin without concentrating the generated NF membrane permeated liquid, and an electrodialysis step S13 in which the NF membrane permeated liquid that has undergone the alkaline earth metal removal step S12 is electrodialyzed to separate the acid solution and the alkaline solution.
  • an alkaline earth metal removal step S12 in which the alkaline earth metal contained in the NF membrane permeated liquid is removed by a chelate resin or an ion exchange resin without concentrating the generated NF membrane permeated liquid
  • an electrodialysis step S13 in which the NF membrane permeated liquid that has undergone the alkaline earth metal removal step S12 is electrodialyzed to separate the
  • the alkaline earth metal ion concentration of the NF membrane permeated liquid produced in the first step S1 is high (for example, about several hundred ppm)
  • a step of adding sodium hydroxide, sodium carbonate, or the like to the NF membrane permeated liquid to crystallize and remove alkaline earth metal ions such as magnesium ions and calcium ions may be provided before the alkaline earth metal removal step S12.
  • the alkaline earth metal ion concentration of the NF membrane permeated liquid produced in the first step S1 is low, the alkaline earth metal removing step S12 may be omitted.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Hydrology & Water Resources (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Electrochemistry (AREA)
  • Molecular Biology (AREA)
  • Nanotechnology (AREA)
  • Biomedical Technology (AREA)
  • Removal Of Specific Substances (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
PCT/JP2022/047822 2022-01-24 2022-12-26 二酸化炭素の固定化方法 WO2023140055A1 (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2023575161A JPWO2023140055A1 (enrdf_load_stackoverflow) 2022-01-24 2022-12-26

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2022-008721 2022-01-24
JP2022008721 2022-01-24

Publications (1)

Publication Number Publication Date
WO2023140055A1 true WO2023140055A1 (ja) 2023-07-27

Family

ID=87348229

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/047822 WO2023140055A1 (ja) 2022-01-24 2022-12-26 二酸化炭素の固定化方法

Country Status (2)

Country Link
JP (1) JPWO2023140055A1 (enrdf_load_stackoverflow)
WO (1) WO2023140055A1 (enrdf_load_stackoverflow)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005262078A (ja) * 2004-03-18 2005-09-29 Nitto Denko Corp 造水方法
JP2011056345A (ja) * 2009-09-07 2011-03-24 Toshiba Corp 淡水化システム
JP2012213767A (ja) * 2011-03-31 2012-11-08 Solt Industry Center Of Japan Ｋ及びＭｇの回収方法及び装置
US20130020259A1 (en) * 2011-07-18 2013-01-24 Katana Energy Llc Membrane and Electrodialysis based Seawater Desalination with Salt, Boron and Gypsum Recovery
US20130248445A1 (en) * 2010-09-30 2013-09-26 Sijing Wang Membrane filtration process with high water recovery
JP2015524787A (ja) * 2012-08-16 2015-08-27 ラマン, アヒランRAMAN, Ahilan 塩化ナトリウム鹹水の製造方法及びシステム
WO2021261410A1 (ja) * 2020-06-22 2021-12-30 学校法人早稲田大学 二酸化炭素の固定化方法
WO2022030529A1 (ja) * 2020-08-05 2022-02-10 学校法人早稲田大学 二酸化炭素の固定化方法
WO2022226333A1 (en) * 2021-04-23 2022-10-27 Enviro Water Minerals Company, Inc. Sustainable desalination systems and methods using recycled brine streams

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005262078A (ja) * 2004-03-18 2005-09-29 Nitto Denko Corp 造水方法
JP2011056345A (ja) * 2009-09-07 2011-03-24 Toshiba Corp 淡水化システム
US20130248445A1 (en) * 2010-09-30 2013-09-26 Sijing Wang Membrane filtration process with high water recovery
JP2012213767A (ja) * 2011-03-31 2012-11-08 Solt Industry Center Of Japan Ｋ及びＭｇの回収方法及び装置
US20130020259A1 (en) * 2011-07-18 2013-01-24 Katana Energy Llc Membrane and Electrodialysis based Seawater Desalination with Salt, Boron and Gypsum Recovery
JP2015524787A (ja) * 2012-08-16 2015-08-27 ラマン, アヒランRAMAN, Ahilan 塩化ナトリウム鹹水の製造方法及びシステム
WO2021261410A1 (ja) * 2020-06-22 2021-12-30 学校法人早稲田大学 二酸化炭素の固定化方法
WO2022030529A1 (ja) * 2020-08-05 2022-02-10 学校法人早稲田大学 二酸化炭素の固定化方法
WO2022226333A1 (en) * 2021-04-23 2022-10-27 Enviro Water Minerals Company, Inc. Sustainable desalination systems and methods using recycled brine streams

Also Published As

Publication number Publication date
JPWO2023140055A1 (enrdf_load_stackoverflow) 2023-07-27

Similar Documents

Publication Publication Date Title
WO2022030529A1 (ja) 二酸化炭素の固定化方法
CN104843927B (zh) 脱硫废水零排放工艺及系统
AU2005285052B2 (en) Water desalination process and apparatus
US20170036937A1 (en) Method for treating aqueous saline streams
CN101932528A (zh) 用于处理废水的方法和系统
CN115784503A (zh) 一种从盐湖卤水中提锂并制备电池级碳酸锂的系统及方法
US20230049146A1 (en) Lithium recovery from liquid streams
TWI619676B (zh) 製造氯化鈉鹽水之方法及系統
WO2021261410A1 (ja) 二酸化炭素の固定化方法
JP5968524B2 (ja) 水処理方法及び水処理システム
CN110937728A (zh) 一种脱硫废水的处理方法及处理系统
Ramasamy Short review of salt recovery from reverse osmosis rejects
WO2016160810A1 (en) Osmotic separation systems and methods
RU2720420C1 (ru) Способ сорбционного извлечения лития из литийсодержащих рассолов
CN214829617U (zh) 钢铁湿法脱硫废水处理系统
GB2394678A (en) A solution rich in magnesium chloride (MgCl2) produced from seawater.
US20240123400A1 (en) Systems and methods for integrated direct air carbon dioxide capture and desalination mineral recovery
CN209923115U (zh) 一种含盐废水的盐回收系统以及处理系统
CN112661335A (zh) 一种氟化铵废盐水资源化利用方法及装置
WO2023140055A1 (ja) 二酸化炭素の固定化方法
CN111362490A (zh) 脱硫废水的处理方法及系统
WO2024080132A1 (ja) 二酸化炭素の固定化方法
CN109607582A (zh) 一种从脱硫废水中回收镁盐的方法及系统
WO2025022834A1 (ja) 二酸化炭素の固定化方法
AU2022305126B2 (en) Method and installation for producing desalted and mineralized water from saline water

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22922205

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2023575161

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 22922205

Country of ref document: EP

Kind code of ref document: A1