+

WO2018035573A1 - Procédé de dessalement - Google Patents

Procédé de dessalement Download PDF

Info

Publication number
WO2018035573A1
WO2018035573A1 PCT/AU2017/050904 AU2017050904W WO2018035573A1 WO 2018035573 A1 WO2018035573 A1 WO 2018035573A1 AU 2017050904 W AU2017050904 W AU 2017050904W WO 2018035573 A1 WO2018035573 A1 WO 2018035573A1
Authority
WO
WIPO (PCT)
Prior art keywords
ion
ammonium bicarbonate
exchange
bed
resin
Prior art date
Application number
PCT/AU2017/050904
Other languages
English (en)
Inventor
Richard Mark Pashley
Nainanayake Pathirannehelage Ganga Nilmini Chandrasekara
Original Assignee
Newsouth Innovations Pty Limited
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
Priority claimed from AU2016903405A external-priority patent/AU2016903405A0/en
Application filed by Newsouth Innovations Pty Limited filed Critical Newsouth Innovations Pty Limited
Publication of WO2018035573A1 publication Critical patent/WO2018035573A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J47/00—Ion-exchange processes in general; Apparatus therefor
    • B01J47/02—Column or bed processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J47/00—Ion-exchange processes in general; Apparatus therefor
    • B01J47/02—Column or bed processes
    • B01J47/04—Mixed-bed processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J49/00—Regeneration or reactivation of ion-exchangers; Apparatus therefor
    • B01J49/50—Regeneration or reactivation of ion-exchangers; Apparatus therefor characterised by the regeneration reagents
    • 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
    • C02F1/20—Treatment of water, waste water, or sewage by degassing, i.e. liberation of dissolved gases

Definitions

  • the present invention relates to a method of desalinating a salt solution.
  • Ion exchange (IEX) resins have been used for many years in various water treatment related practices.
  • mixed-bed ion exchange resins have been used to remove scale-forming ions such as Ca 2+ and Mg 2+ from feed water and to produce high quality water (i.e. comparable to distilled water) from tap water.
  • Such resins can also be used for the desalination of fairly concentrated brackish water and even sea water, without the need for high pumping pressures, extensive pretreatment or high thermal energy input.
  • utilization of ion-exchange resins on a large scale for desalination of water has been limited by the depletion of the resin and the need for large volumes of acid and base solutions to regenerate the spent resins, limiting the economic viability of the technique.
  • Ion-exchange resins are insoluble polymers that have bound ions which are able to be exchanged with other ions in solutions which come in contact with them.
  • the resins comprise charged functional groups, with mobile counter-ions of the opposite charge associated with the functional groups. It is the mobile counter-ions which may exchange with other ions of similar charge in an "ion exchange" process.
  • An ion- exchange resin may be referred to as "spent" when the majority of the mobile counter- ions associated with the charged functional groups have been replaced with the other ions of similar charge.
  • the mobile counter-ion of the cation-exchange resin is typically H + and the mobile counter-ion of the anion-exchange resin is typically OH " .
  • the cation- exchange resin and the anion-exchange resin are in the form of beads housed in an ion- exchange column.
  • the resin beads are firstly separated into the beads of the cation-exchange resin and the beads of the anion-exchange resin, and each component is then washed separately with a regenerating solution.
  • a regenerating acid solution is used to wash and thereby remove the exchanged cation on the cation-exchange resin.
  • a regenerating basic solution is used to wash and thereby remove the exchanged anion on the anion-exchange resin. Further washing steps (usually using the product water) are then subsequently used to rinse the regenerating solution away from the resin.
  • Some alternative methods have been investigated to regenerate IEX resins, such as thermal energy (e.g. the SirothermTM process), electrical energy (electrodialysis) or mechanical energy (piezodialysis).
  • thermal energy e.g. the SirothermTM process
  • electrical energy electrodialysis
  • mechanical energy pieodialysis
  • resin beads containing both a weak acid component and a weak base component were formed (using either a physical mixture of a weakly acidic resin and a weakly basic resin, or a resin containing both weakly acidic and weakly basic components), having a substantially reduced ion adsorption capacity at higher temperatures, allowing the resins to be regenerated by heating, e.g. to 60° C to 80° C.
  • This process has only been used to dilute brackish water and is currently not used on a large scale as it requires large energy investment during the heat treatment step.
  • the present invention provides a method for desalinating a salt solution, the method comprising the steps of:
  • the ion-exchange bed comprises one or more ion-exchange resins.
  • the one or more ion-exchange resins is in the form of a mixed-bed resin.
  • the mixed-bed resin is comprised of a mixture of a strongly acidic ion-exchange resin and a strongly basic ion-exchange resin.
  • the mixed-bed resin is comprised of a mixture of Amberlite IR 120 and Amberlite IRA 402.
  • the mixed-bed resin is comprised of a mixture of a weakly acidic ion-exchange resin and a weakly basic ion-exchange resin.
  • the mixed-bed resin is comprised of a mixture of Amberlite IRC 86 and Amberlite IRA 67.
  • the ion-exchange bed comprises a first ion-exchange resin in a first zone and a second ion-exchange resin in a second zone, wherein mobile ions of the first ion-exchange resin are oppositely charged to mobile ions of the second ion-exchange 5 resin.
  • the ion-exchange resin is a polymer comprising both an anion exchanger and a cation exchanger on the same polymer.
  • the anion exchanger and cation exchanger of the polymer may be, for example, strongly acidic and strongly basic o exchangers.
  • the anion exchanger and cation exchanger of the polymer may be, for example, weakly acidic and weakly basic exchangers.
  • the eluent comprising ammonium bicarbonate is an aqueous solution of about 0.05 M to about 4 M ammonium bicarbonate.
  • the eluent is5 at a temperature of less than approximately 40 °C, e.g. about 15 °C to about 40 °C, about 15 °C to about 30 °C, or at about room temperature (e.g. at about 20 °C or about 22 °C).
  • the salt comprises a cation selected from Na + , K + , Ca 2+ , Sr 2+ and o Cs + .
  • the salt is selected from the group consisting of NaCl, KC1,
  • the method comprises the further step c) of treating the ammonium bicarbonate solution produced by step b) to remove at least some of the ammonium bicarbonate.
  • the ammonium bicarbonate solution produced by step b) is treated to remove at least some of the ammonium bicarbonate by heating the ammonium bicarbonate solution to produce NH 3 gas and CO 2 gas.
  • the ammonium bicarbonate solution is heated using a bubble column evaporator (BCE) to produce NH 3 gas and CO 2 gas.
  • BCE bubble column evaporator
  • the NH 3 gas and CO 2 gas are used to form a subsequent ammonium bicarbonate solution.
  • the subsequent ammonium bicarbonate solution is used to elute the ion-exchange bed.
  • the present invention provides a method for desalinating a salt solution, the method comprising the steps of:
  • step c) treating the ammonium bicarbonate solution produced by step b) to remove at least some of the ammonium bicarbonate.
  • the method further comprises repeating steps a) to c).
  • the ammonium bicarbonate solution produced by step b) is treated to remove at least some of the ammonium bicarbonate by heating the ammonium bicarbonate solution to produce NH 3 gas and CO 2 gas.
  • the ammonium bicarbonate solution is heated using a bubble column evaporator (BCE) to produce NH 3 gas and CO 2 gas.
  • BCE bubble column evaporator
  • the NH 3 gas and CO 2 gas are used to form a subsequent ammonium bicarbonate solution.
  • the subsequent ammonium bicarbonate solution is used to elute (and thus regenerate) the ion-exchange bed.
  • the salt solution is saline water.
  • Figure 1 is a schematic diagram of the regeneration of a mixed-bed system
  • Figure 2 is a schematic representation of the cation-exchange resin and the anion- exchange resin in the mixed-bed resin used in the Example showing the functional groups (SO 3 " for the cation-exchange resin and NR 3 + , where each R is an alkyl group, for the anion-exchange resin) in the exhausted, or salt-loaded, state (State 1), and in the regenerated, or ammonium bicarbonate -loaded, state (State 2).
  • the functional groups SO 3 " for the cation-exchange resin and NR 3 + , where each R is an alkyl group, for the anion-exchange resin
  • Figure 3 is a graphical representation of the concentration (mol/1) of Na + , CI " and Nl3 ⁇ 4 + in the eluate with the volume of 0.1M ammonium bicarbonate (ml) as the feed solution (eluent) to a NaCl saturated mixed-bed resin at 20°C.
  • Figure 4 is a graphical representation of the cumulative desorption (mmol) of Na + , CI " and NH 4 + in the eluate with the volume of 0.1M ammonium bicarbonate (ml) as the feed solution (eluent) to a NaCl saturated mixed-bed resin at 20°C
  • Figure 5 is a graphical representation of the concentration (mol/1) of Na + and CI " in the eluate with the volume of 0.1M NaCl (ml) as the feed solution (eluent) to an ammonium bicarbonate-loaded mixed-bed resin at 20°C
  • Figure 6 is a graphical representation of the cumulative desorption (mmol) of Na + and
  • FIG. 7 is a schematic diagram for a complete desalination process using a strong acid/strong base 50:50 mixed-bed resin using ammonium bicarbonate regeneration.
  • DW refers to drinking water.
  • the bubble column evaporation (BCE) process is used to decompose the ammonium bicarbonate product solution.
  • the present invention provides a method for treating a salt solution to remove at least some of the salt from the solution.
  • the method comprises a first step of eluting an ion-exchange bed having both cation and anion exchangers with an eluent comprising ammonium bicarbonate to produce an ammonium bicarbonate-loaded ion- exchange bed.
  • the method comprises a second step of eluting the ammonium bicarbonate-loaded ion-exchange bed with the salt solution. Eluting the ammonium bicarbonate-loaded ion-exchange bed with the salt solution produces a solution comprising ammonium bicarbonate as the eluate.
  • the ammonium bicarbonate in the eluate can then be removed, for example, by heating the solution to form NH 3 gas and C0 2 gas.
  • the ion-exchange bed In order for an ion-exchange bed to desalinate a salt solution comprising a salt such as NaCl, the ion-exchange bed must be able to capture by ion exchange, and thus exchange, both the cation and the anion of the salt.
  • the ion-exchange bed must therefore comprise a cation exchanger and an anion exchanger.
  • the mobile counter cation bound to the cation exchanger exchanges with the cation species to be removed from the solution, and the mobile counter anion bound to the anion exchanger exchanges with the anion species to be removed from the solution.
  • the ion- exchange bed is "salt loaded" and must be regenerated for further use.
  • a “salt loaded” ion-exchange bed may also be referred to as “spent” or “exhausted”.
  • a salt-loaded ion-exchange bed is regenerated by separating out the spent cation exchanger and anion exchanger.
  • the spent cation exchanger is typically contacted with a concentrated acid solution to regenerate the cation exchanger.
  • the spent anionic exchanger is typically contacted with a concentrated base to regenerate the anion exchanger.
  • the method of the present invention enables the ion-exchange bed to be regenerated for further use in desalinating a salt solution without the need for separating the ion-exchangers.
  • the method of the present invention does not require the ammonium bicarbonate to be removed from the ion-exchange bed prior to the ammonium bicarbonate -loaded ion-exchange bed being used in the desalination of the salt solution. Eluting the ammonium bicarbonate-loaded ion-exchange bed with the salt solution produces a solution comprising ammonium bicarbonate.
  • the ammonium bicarbonate can be removed from the solution by simple, low cost processes, such as by heating the solution to form NH 3 gas and CO 2 gas which are then separated from the solution.
  • the ammonium bicarbonate can be removed from the solution, it is not necessary to remove the ammonium bicarbonate from the ion-exchange bed prior to the ammonium bicarbonate-loaded ion-exchange bed being used in the desalination of the salt solution.
  • NH 3 gas and CO 2 gas recovered from the ammonium bicarbonate solution can be regenerated into an ammonium bicarbonate solution and the resultant ammonium bicarbonate solution used to again elute and regenerate the ion-exchange bed.
  • the ion-exchange bed used in step a) may be a salt-loaded ion-exchange bed previously used in a desalination process.
  • the method of the present invention enables such a salt-loaded ion-exchange bed to be regenerated for further use in desalinating a salt solution.
  • the ion-exchange bed used in step a) may alternatively be an ion- exchange bed as initially manufactured or supplied by a supplier which requires treatment to replace the mobile-ions of the bed as manufactured or supplied with mobile ions suitable for use in a desalination method.
  • ion exchange broadly refers to an exchange of ions between two electrolytes or between an electrolyte solution and a solid or gel (e.g. an ion- exchange resin).
  • the ion exchange process can be used to purify, separate, and decontaminate aqueous and other ion-containing solutions with "ion exchangers".
  • an "ion exchanger” is a substance capable of exchanging an ion with an ion in solution. Ion exchangers are either cation exchangers that exchange positively charged ions (cations) or anion exchangers that exchange negatively charged ions (anions).
  • An "ion-exchange bed” is a bed comprising one or more ion exchangers through which an eluent can pass and exchange ions with the ion exchanger.
  • the bed may comprise the one or more ion exchangers in any manner that allows the eluent to pass through the bed and exchange ions with the one or more ion exchangers.
  • the bed typically comprises particles of one or more ion exchangers, e.g. in the form of beads.
  • the ion- exchange bed may be housed, for example, in an ion-exchange column.
  • the ion- exchange bed used in the method of the present invention comprises both cation and anion exchangers, that is, the ion-exchange bed comprises at least one cation exchanger and at least one anion exchanger.
  • the ion-exchange bed may, for example, comprise a uniform mixture of cation exchangers and anion exchangers or may comprise regions or zones comprising different proportions of cation exchangers and anion exchangers.
  • the ion-exchange bed comprises an amphoteric exchanger, that is, a single substance comprising both a cation exchanger and an anion exchanger.
  • the cation and anion exchangers may, for example, be ion-exchange resins, zeolites, porous ceramics or a clay, e.g. montmorillonite.
  • the cation and anion exchangers are ion-exchange resins.
  • the term "ion-exchange resin” broadly refers to an insoluble matrix of an organic polymeric material comprising a charged functional group, where the charged functional group has an exchangeable (or mobile) counter-ion associated with the charged functional group.
  • the functional group may be weakly acidic or strongly acidic (e.g. sulphonates, -SO 3 " ), or may be weakly basic or strongly basic (e.g. quaternary ammonium, -CH 2 N + (CH 3 ) 3 ).
  • a cation-exchange resin is able to exchange cations with cations in a solution.
  • Such a resin comprises an acidic functional group with an associated cation.
  • An anion- exchange resin is able to exchange anions with anions in a solution.
  • Such a resin comprises a basic functional group with an associated anion.
  • a reference to a "weakly basic” (or “weak base”) ion- exchange resin refers to an ion-exchange resin with a weakly basic functional group
  • a reference to a "weakly acidic" (or “weak acid”) ion-exchange resin refers to an ion-exchange resin with a weakly acidic functional group.
  • a reference to a "strongly basic” (or “strong base”) ion-exchange resin refers to an ion-exchange resin with a strongly basic functional group
  • a reference to a “strongly acidic” (or “strong acid”) ion-exchange resin refers to an ion-exchange resin with a strongly acidic functional group
  • a mobile counter-ion is associated with each charged functional group.
  • the mobile counter-ion may exchange with other ions of similar charge in an "ion exchange” process.
  • An ion-exchange resin may be referred to as "spent” (or “exhausted” or “salt loaded”) when the majority (more than 50%, e.g. more than 70%, 80% or 90%) of the mobile counter-ions associated with the charged functional groups have been replaced with ions from the eluent.
  • Regeneration of a spent ion-exchange resin may be achieved by reversing the ion exchange reactions referred to above.
  • a spent ion-exchange resin is regenerated by eluting the spent ion-exchange resin with a relatively concentrated solution of the original mobile counter-ions.
  • the ion-exchange bed may comprise one or more ion-exchange resins.
  • the one or more ion-exchange resins are in the form of a mixed-bed resin.
  • a mixed-bed resin is a resin bed in which separate particles of a cation-exchange resin and an anion-exchange resin, usually in the form of beads, are mixed together. That is, particles of a cation-exchange resin are mixed with particles of an anion- exchange resin to form a mixed resin bed or mixed-bed resin.
  • the mixed-bed resin comprises a uniform mixture of the particles of the cation- exchange resin and anion-exchange resin.
  • a mixed-bed resin may comprise a mixture of a cation-exchange resin and an anion exchange resin where the mixture comprises different relative proportions of the cation-exchange resin and the anion exchange resin in different regions of the mixed-bed resin.
  • an ion-exchange bed comprising a cation-exchange resin and an anion-exchange resin may alternatively comprise the cation-exchange resin and the anion-exchange resin in configurations other than a mixture of the resins.
  • the cation-exchange resin and anion- exchange resin may be provided in series, e.g. a cationic resin zone or unit followed by an anionic resin zone or unit, and vice versa.
  • the ion-exchange bed comprises a mixed bead resin.
  • Mixed bead resins are beads of a resin which comprise both an acidic functional group and a basic functional group, with an associated cation and anion, respectively, on the same bead, that is, the bead comprises both a cation-exchanger and an anion-exchanger.
  • Examples of mixed bead resin are given, for example, in Chandrasekara, N.P.G.N. and R.M. Pashley, Study of a new process for the efficient regeneration of ion-exchange resins. Desalination, 2015. 357(0): p. 131-139.
  • the ion exchange bed is in the form of a mixed-bed resin comprising particles of a cation-exchange resin and particles of an anion-exchange resin.
  • An ion-exchange resin typically comprises a partially cross linked aliphatic polymer, such as cross-linked polystyrene, comprising charged functional groups having an exchangeable counter-ion associated with the functional group.
  • the resin polymer comprises one or more additional copolymers.
  • the copolymers may include, but are not limited to, butadiene, ethylene, propylene, acrylonitrile, styrene, acrylic, vinylidene chloride, vinyl chloride, and derivatives and mixtures thereof.
  • the charged functional groups can be an integral part of the monomer or can be incorporated into the polymer after polymerisation.
  • the ion-exchange resin may be provided in any shape and size, including beads, rods, disks or combinations of more than one shape.
  • the ion-exchange resin may also include a mixture of particle sizes, such as a mixture of large and small particles.
  • the ion-exchange resins are typically in the form of beads.
  • the beads are small (0.2 to 1.5 mm diameter) porous beads with a high surface area.
  • the cation-exchange resin is a strongly acidic cation-exchange resin comprising a polystyrene matrix and sulfonic acid functional groups.
  • the cation-exchange resin is a weakly acidic cation-exchange resin, such as a cross-linked acrylic acid with carboxylic acid functional group, a cross-linked methacrylic acid with carboxylic acid functional group, or mixture thereof.
  • the anion-exchange resin is a strongly basic anion-exchange resin comprising quaternary amino groups, for example, trimethylammonium groups, e.g. poly AMPS.
  • the anion-exchange resin is a weakly basic anion-exchange resin comprising primary, secondary or tertiary amine groups, e.g. polyethylene amine.
  • Amberlite® IRA 402 is a styrene divinylbenzene copolymer, comprising the functional group trimethyl ammonium.
  • Diaion WA30 is produced by Mitsubishi Chemical Corporation.
  • the "form" of the resin referred to in Table 1 is the form of the resin as supplied by the manufacturer.
  • the resins may be used in the form supplied by the manufacturer or the resins may be associated with another counter ion.
  • Step (a) eluting with an eluent comprising ammonium bicarbonate
  • the method comprises a first step of eluting the ion-exchange bed with an eluent comprising ammonium bicarbonate (ammonium hydrogen carbonate) to produce an ammonium bicarbonate-loaded ion-exchange bed.
  • the eluent comprising ammonium bicarbonate may be aqueous or non-aqueous. However, the eluent is typically an aqueous solution of ammonium bicarbonate.
  • a reference herein to an "aqueous solution” refers to a solution in which water is the only solvent or is at least 50 % (e.g. at least 80%, at least 90 %, at least 95 %, or at least 99 %) by weight of the total solvents in the solution.
  • a reference to an aqueous solution of ammonium bicarbonate refers to an ammonium bicarbonate solution in which water is the only solvent or is at least 50 % by weight of the total solvents in the solution.
  • An aqueous ammonium bicarbonate solution may comprise a solution of ammonium bicarbonate in water and a water miscible co-solvent, such as methanol or ethanol, provided that water comprises at least 50 % by weight of the solvents present.
  • water comprises at least 90 %, at least 95 % or at least 99 %, by weight of the total solvents in the solution.
  • an ion-exchange bed may be referred to as "ammonium bicarbonate loaded" when the majority (more than 50%, e.g. more than 70%, 80% or 90%) of the mobile ions associated with the cation and anion exchangers have been replaced with Nl3 ⁇ 4 + or HCO 3 " ions.
  • the eluent comprising ammonium bicarbonate is an aqueous solution comprising a concentration of ammonium bicarbonate of about 0.05 M or greater.
  • the eluent comprising ammonium bicarbonate may, for example, be an aqueous solution comprising about 0.05 M to about 4.0 M ammonium bicarbonate.
  • the eluent comprising ammonium bicarbonate is an aqueous solution comprising about 0.05 to 2.0 M ammonium bicarbonate.
  • the eluent comprising ammonium bicarbonate is an aqueous solution comprising about 0.05 to 1.0 M ammonium bicarbonate.
  • the eluent comprising ammonium bicarbonate is an aqueous solution comprising about 0.05 to 0.5 M ammonium bicarbonate. Concentrations of ammonium bicarbonate above 0.5 M may cause bubbling of the ammonium bicarbonate solution, which in turn may produce channels inside a mixed-bed resin. This bubbling can, however, be reduced or completely prevented by application of a modest (e.g. ⁇ 1 bar) over-pressure acting on the concentrated solution. Concentrations of ammonium bicarbonate below 0.05 M may not be sufficient to effectively remove the ions associated with the ion- exchangers to form an ammonium bicarbonate-loaded ion-exchange bed.
  • Step (b) - eluting with the salt solution
  • salt is used to refer broadly to an ionic compound which is electrically neutral (i.e. without a net charge) in its solid form, but which dissolves into cations (positively charged ions) and anions (negative ions) in solution.
  • a salt is generally formed from the neutralization reaction of an acid and a base.
  • the component ions of a salt can be inorganic, such as chloride (CI " ), or organic, such as acetate (CH 3 CO 2 " ); and can be monatomic, such as fluoride (F " ), or polyatomic, such as sulfate (SO 4 2" ).
  • CI chloride
  • F fluoride
  • SO 4 2 sulfate
  • Salts that hydrolyze to produce hydroxide ions when dissolved in water are basic salts, whilst those that hydrolyze to produce hydronium ions in water are acidic salts.
  • Neutral salts are those that are neither acid nor basic salts.
  • An ion of the salt may be radioactive, for example, a salt comprising a radioactive isotope of Sr 2+ or Cs + .
  • Saline water is a general term for water that contains a significant concentration (i.e. >500 ppm) of dissolved salts (typically NaCl). The salt concentration is usually expressed in parts per thousand or parts per million (ppm).
  • Saline water may include, but is not limited to, groundwater, brackish water, sea water, hypersaline water, brine, produced water or process water.
  • the salt may be any salt (other than ammonium bicarbonate).
  • the salt may, for example, be selected from the group consisting of NaCl, KC1, CaCl 2 , SrCl 2 and CsCl.
  • the salt solution is typically an aqueous solution. Typically water is the only solvent in the salt solution. However, the process of the invention can also be used to desalinate solutions comprising salts dissolved in polar solvents other than water.
  • the salt solution comprises one or more cations selected from Na + , K + , Ca 2+ , Sr 2+ and Cs + .
  • the salt solution comprises one or more anions selected from CI “ , F “ , Br “ , CH 3 C0 2 “ , P0 4 3” and S0 4 2" .
  • the salt solution is an aqueous solution comprising one or more dissolved salts selected from NaCl, KC1, CaCl 2 , MgSO/ t , A1 2 (SC>4)3, FeCl 3 , ZnCl 2 , SrCl 2 and CsCl.
  • ammonium bicarbonate solution that is, a solution comprising ammonium bicarbonate (and a salt-loaded ion-exchange bed).
  • the ammonium bicarbonate solution comprises Nt3 ⁇ 4 + and HCO 3 " ions.
  • the ammonium bicarbonate can readily be removed from the ammonium bicarbonate solution as described below to form a solution having a lower salt concentration than the salt solution. Step (c)-treatment of the ammonium bicarbonate solution
  • ammonium bicarbonate may readily be removed from the ammonium bicarbonate solution produced by step b) by heating the ammonium bicarbonate solution to produce NH 3 gas and CO 2 gas.
  • the ammonium bicarbonate solution can be heated by heating the solution to about 60°C to produce NH 3 gas and CO 2 gas.
  • the NH 3 gas and CO 2 gas, being in gaseous form, can then be easily separated from the solution.
  • the ammonium bicarbonate solution produced by step b) is heated using a bubble column evaporator (BCE) to remove the ammonium bicarbonate by converting the ammonium bicarbonate into NH 3 gas and CO 2 gas.
  • BCE bubble column evaporator
  • bubbles of a gas are passed through a solution. Heated gas may be used so that as the hot bubbles pass through the solution, they convert some of the ammonium bicarbonate into NH 3 gas and CO 2 gas and also capture and remove at least some of the formed NH 3 gas and CC> 2 gas from the solution.
  • the BCE process can be used as a quick and efficient manner to convert the ammonium bicarbonate into NH 3 gas and CO 2 gas and remove the NH 3 gas and C0 2 gas from the solution.
  • ammonium bicarbonate is decomposed into NH 3 and CO 2 gases at temperatures of about 60 °C.
  • the use of a BCE to convert ammonium bicarbonate in a solution into NH 3 and CO 2 and remove the NH 3 and CO 2 from the solution is described in M. Shahid, X. Xue, C. Fan, B. W. Ninham and R. M. Pashley, Study of a Novel Method for the Thermolysis of Solutes in Aqueous Solution Using a Low Temperature Bubble Column Evaporator. J.
  • the ammonium bicarbonate solution may be heated in the presence of air or another gas.
  • the formed NH 3 and CO 2 gases are mixed with air or other gases.
  • the resulting mixture of gases, comprising NH 3 and CO 2 can be used to form a further ammonium solution without separation of the gases by, for example, passing the mixture of gases through water or an aqueous solution at a temperature of about room temperature or lower, resulting in the NH 3 and CO 2 dissolving in the water to form an ammonium bicarbonate solution.
  • the NH 3 gas and CO 2 gas may be separated from the mixture of gases, for example, in order to store the NH 3 gas and CO 2 gas for later use to form an ammonium bicarbonate solution.
  • the NH 3 and C0 2 gases may be separated from the mixture of gases using conventional gas separation techniques.
  • a hollow-fibre membrane is used to separate the NH 3 gas and CO 2 gas from the ammonium bicarbonate solution.
  • the ammonium bicarbonate solution is heated just prior to entering a hollow-fibre membrane gas exchange unit, where a counter flow air current continuously collects the decomposed gases, NH 3 gas and CO 2 gas, on the other side of the hollow-fibre membrane.
  • gas exchange units are available commercially and use either dense membranes, which allow gases to diffuse through the permeable hollow-fibre membrane, or use porous but hydrophobic hollow-fibre membranes.
  • the NH 3 gas and CO 2 gas can readily be dissolved in water, for example water at about room temperature, e.g. at about 15°C to 25°C, to form an ammonium bicarbonate solution.
  • water for example water at about room temperature, e.g. at about 15°C to 25°C
  • the NH 3 gas and CO 2 gas are dissolved in the water by contacting the NH 3 gas and CO 2 gas, optionally in a mixture with air or other gases, with the water, for example, by bubbling the gases through the water or passing the water through an atmosphere of the gases.
  • An elevated pressure may be used to expedite the dissolution of the NH 3 gas and CO 2 gas.
  • the ammonium bicarbonate solution can then be used to again regenerate the ion-exchange bed after it has been used in the desalination of the salt solution.
  • the present invention provides a method for desalinating a salt solution comprising the steps of:
  • step b) treating the ammonium bicarbonate solution of step b) to produce NH 3 gas and CO 2 gas to thereby remove at least some of the ammonium bicarbonate from the solution; and, optionally,
  • step d) using the NH 3 gas and C0 2 gas of step c) to form an ammonium bicarbonate solution and repeating steps a) to c).
  • the term "desalinating” is broadly used to refer to a process for removing at least some amount of a dissolved salt from a salt solution.
  • the salt solution is an aqueous solution.
  • the desired concentration of dissolved salts in desalinated water is at or below a threshold for potable municipal water, although it will be appreciated that this threshold may vary depending on the potential use for the water. For example, higher concentrations of dissolved salts may be tolerated for stock water, irrigation water, or water for use in industry or mining processing.
  • the cyclic nature of the method comprising steps a) to d) referred to above has significant inherent advantages, in that large amounts of acid and base waste regenerants (and waste from subsequent washes) are not generated. Such a cyclic method would be beneficial in the treatment and removal of radioactive ions in solution, for example, in nuclear power waste water.
  • the methods of the present invention may be used to desalinate brackish water or sea water.
  • the method can be used on a large or small scale.
  • the method does not require the use of high pressures or temperatures, or the use of concentrated acid and base solutions.
  • Reverse osmosis desalination processes can be noisy in practice, presenting a difficulty for use in some circumstances, e.g. on a ship or submarine.
  • the method of the present invention can be carried out in a relatively quiet manner.
  • a strong acid resin (Amberlite IR 120, H + form) and a strong base resin (Amberlite IRA 402, CI " form) were used for the mixed-bed system, purchased as the analytical grade from Sigma-Aldrich, Australia.
  • Ammonium bicarbonate (99%) was obtained from May & Baker LTD, Dagenham, England and 99% sodium chloride was obtained from Sigma-Aldrich, Australia.
  • Amberlite IR 120 which was received initially in its H + form, was converted to the Na + form by exposing to brine solution, followed by washing with Mili-Q water to remove the excessive NaCl present at the resin.
  • the strong acid resin (Amberlite IR 120, Na + form) and a strong base resin (Amberlite IRA 402, CI " form) samples were taken in roughly 4.2 g and 5.4 g samples, as their wet weight, respectively, to maintain roughly equal IEX capacity within the columns.
  • the resin beads were then mixed and packed into a thin column without trapping any air bubbles, with Mili-Q water up to bed heights of about 14.5 cm.
  • the mixed-bed systems regenerated by AB (refer Figure 2, State 2), was then exposed from the top to 0.1M NaCl solutions (at pH 5.6) at 20°C, in a continuous flow system at a rate of lOml/hr.
  • the eluate was collected in 10 ml samples and tested for the level of Na + , NHt + and CI " until it reached the values of Na + and CI " close to drinking quality water, as per the guidelines of the World Health Organisations (WHO). All of the chemical analyses were performed at least twice to ensure the accuracy of the results.
  • Table 2- Amount of Na , CI " and NH4 in each 10 ml of eluant sample during the regeneration of exhausted mixed-bed resins and cumulative millimoles (Cum.mmol) eluted.
  • the decomposition gases produced in the BCE process can then be used to regenerate concentrated AB solutions for further re-use.
  • IEX selectivity coefficients for various cations are quite diverse and Na + typically has higher selectivity compared to the NH ion.
  • the law of mass action plays a dominant role, especially for strong acid and strong base resins, thus replacing Na + by N3 ⁇ 4 + is readily achieved and is completely reversible, as confirmed by the results obtained in this study.
  • the IEX selectivity coefficients for anions are different and CI " typically has stronger binding than HCO 3 " [DOWEXTM Ion Exchange Resins: Using Ion Exchange Resin Selectivity Coefficients. Technical Information: 1-3].
  • the mass action law supports the regeneration process of the strong acid/strong base mixed-bed resins, even though the relative ion selectivity coefficients facilitate the desalting process.
  • the properties shown by the AB regenerated strong acid/strong base mixed-bed resins demonstrate that continuous flow column processes could be used to desalt NaCl solutions, at relatively high concentrations (e.g. 0.1 M or higher), producing a product solution of ammonium bicarbonate (AB).
  • This solution can be readily decomposed at modest temperatures to produce desalted water.
  • the gases produced, ammonia and carbon dioxide, can then be recollected in cold water to re-form a concentrated AB solution.
  • the method of the invention can therefore be used to provide a complete and continuous desalination process, which does not require heating of the resin, separation of the resin, or exposure of the resin to strong acids and bases during regeneration. An example of such a process is described schematically in Fig. 7.
  • This process combines the purification of saline water to drinking water together with regeneration of exhausted resins, through a recycling process, with low chemical waste.
  • the aqueous salt solution comprising dissolved NaCl (Vi NaCl feed (aq)) is eluted through the ammonium bicarbonate-load mixed-bed ion- exchange resin (AB Resin) to form an ammonium bicarbonate solution (Vi DW + AB (aq)) and a NaCl-loaded resin (NaCl Resin).
  • the resultant ammonium bicarbonate solution may be heated, for example in a BCE, to form CO 2 (gas) and NH 3 (gas) which are separated from the remainder of the solution, thus resulting in desalted drinking water (Vi/2 DW product).
  • the CO 2 (gas) and NH 3 (gas) can then be used to form a concentrated ammonium bicarbonate solution (Vi/2 Cone. AB (aq)), for example, by dissolving the CO 2 (gas) and NH 3 (gas) in water at a temperature of about 20°C or lower, optionally at above atmospheric pressure.
  • the resultant concentrated ammonium bicarbonate solution may then be used to regenerate the NaCl-loaded resin forming a concentrated NaCl-waste solution and a regenerated ammonium bicarbonate-loaded resin.
  • the present invention therefore enables the removal of salts from saline water using commercial acid and base resins combined together in a single column.
  • Ammonium bicarbonate solutions can be used as a regenerant solution throughout this process without the need for separating or heating of the resins, which offers an effective process for continuous desalination together with the production of drinking quality water.
  • the complete desalting process could be widely used commercially because it does not depend on the costly consumption of acid and base solutions for resin regeneration.
  • a further advantage is that the resins are never exposed to concentrated acids or bases, so increasing their operating life.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Treatment Of Water By Ion Exchange (AREA)

Abstract

La présente invention concerne un procédé de dessalement d'une solution saline, le procédé comprenant les étapes consistant à : a) éluer un lit à échange d'ions contenant à la fois des échangeurs de cations et d'anions avec un éluant comprenant du bicarbonate d'ammonium pour produire un lit à échange d'ions chargé de bicarbonate d'ammonium ; et b) éluer le lit à échange d'ions chargé de bicarbonate d'ammonium avec la solution saline.
PCT/AU2017/050904 2016-08-26 2017-08-25 Procédé de dessalement WO2018035573A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2016903405A AU2016903405A0 (en) 2016-08-26 Desalination Process
AU2016903405 2016-08-26

Publications (1)

Publication Number Publication Date
WO2018035573A1 true WO2018035573A1 (fr) 2018-03-01

Family

ID=61246682

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU2017/050904 WO2018035573A1 (fr) 2016-08-26 2017-08-25 Procédé de dessalement

Country Status (1)

Country Link
WO (1) WO2018035573A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020118371A1 (fr) * 2018-12-12 2020-06-18 Newsouth Innovations Pty Limited Résine pour le dessalement et processus de régénération
CN112279907A (zh) * 2019-07-27 2021-01-29 深圳市健元医药科技有限公司 一种索玛鲁肽的纯化方法
US20220025091A1 (en) * 2018-12-12 2022-01-27 Newsouth Innovations Pty Limited Resin for desalination and process of regeneration
CN115754048A (zh) * 2022-11-09 2023-03-07 南开大学 超滤管辅助酶解及加热潮解除盐的蛋白组学前处理方法
WO2024086871A1 (fr) * 2022-10-27 2024-05-02 Hydric Desalination Pty Ltd Nouvelle régénération de résines échangeuses d'ions à lit mélangé pour dessalement d'eau de mer

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2776258A (en) * 1953-04-28 1957-01-01 Ionics Ion-exchange-regenerant recovery
WO1989006221A1 (fr) * 1987-12-30 1989-07-13 Ferenc Borsos Procede et appareil de traitement d'eau brute
RU2036160C1 (ru) * 1991-08-29 1995-05-27 Научно-технический кооператив "Поиск" Способ обессоливания воды

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2776258A (en) * 1953-04-28 1957-01-01 Ionics Ion-exchange-regenerant recovery
WO1989006221A1 (fr) * 1987-12-30 1989-07-13 Ferenc Borsos Procede et appareil de traitement d'eau brute
RU2036160C1 (ru) * 1991-08-29 1995-05-27 Научно-технический кооператив "Поиск" Способ обессоливания воды

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SHAHID, M. ET AL.: "Study of a Novel Method for the Thermolysis of Solutes in Aqueous Solution Using a Low Temperature Bubble Column Evaporator", THE JOURNAL OF PHYSICAL CHEMISTRY B, vol. 119, no. 25, 11 June 2015 (2015-06-11), pages 8072 - 8079, XP055332447 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020118371A1 (fr) * 2018-12-12 2020-06-18 Newsouth Innovations Pty Limited Résine pour le dessalement et processus de régénération
US20220025091A1 (en) * 2018-12-12 2022-01-27 Newsouth Innovations Pty Limited Resin for desalination and process of regeneration
CN112279907A (zh) * 2019-07-27 2021-01-29 深圳市健元医药科技有限公司 一种索玛鲁肽的纯化方法
CN112279907B (zh) * 2019-07-27 2023-10-03 深圳市健元医药科技有限公司 一种索玛鲁肽的纯化方法
WO2024086871A1 (fr) * 2022-10-27 2024-05-02 Hydric Desalination Pty Ltd Nouvelle régénération de résines échangeuses d'ions à lit mélangé pour dessalement d'eau de mer
CN115754048A (zh) * 2022-11-09 2023-03-07 南开大学 超滤管辅助酶解及加热潮解除盐的蛋白组学前处理方法
CN115754048B (zh) * 2022-11-09 2024-10-25 南开大学 超滤管辅助酶解及加热潮解除盐的蛋白组学前处理方法

Similar Documents

Publication Publication Date Title
Zhang et al. Sustainable treatment of desulfurization wastewater by ion exchange and bipolar membrane electrodialysis hybrid technology
WO2018035573A1 (fr) Procédé de dessalement
JP3174036U (ja) 低エネルギーの電気脱イオン装置
TWI727046B (zh) 水處理方法、水處理裝置及離子交換樹脂之再生方法
US20110180477A1 (en) Low energy system and method of desalinating seawater
Duan et al. Achieving low-cost, highly selective nitrate removal with standard anion exchange resin by tuning recycled brine composition
JP2013528487A (ja) 水処理プロセス
KR20100099227A (ko) 수처리를 위한 시스템 및 방법
JP7003507B2 (ja) リチウムの回収方法
US20160229711A1 (en) Resin regeneration method for reducing organic contaminants
Wang et al. Ion exchange enabled selective separation from decontamination to desalination to decarbonization: recent advances and opportunities
Chandrasekara et al. Regeneration of strong acid/strong base mixed-bed resins using ammonium bicarbonate (AB) for a sustainable desalination process
Kovtun et al. Analysis of existing methods for improving the physical and chemical conditions of the ion exchange process in water treatment
Trokhymenko et al. Development of low waste technology of water purification from copper ions
US20150251928A1 (en) Ion exchange methods for treating water hardness
JP3045378B2 (ja) 海水の複合処理用の方法
EP3268316A1 (fr) Élimination d'iodure à partir de saumure à l'aide de résines de ralentissement d'ions
Ramzan et al. Performance analysis of cation and anion exchangers in water treatment plant: an industrial case study
US20220025091A1 (en) Resin for desalination and process of regeneration
Bolto et al. An ion-exchange process with thermal regeneration XII. Desalting of sewage effluents
RU2655141C1 (ru) Способ удаления кислорода из воды
de Torres Vincent et al. Beneficial reuse of treated municipal wastewater and flue gas carbon dioxide via combined ion exchange
Dydo et al. Boron removal using ion exchange membranes
RU2257265C1 (ru) Способ регенерации слабокислотных карбоксильных катионитов
WO2004103545A2 (fr) Recyclage d'agent regenerant

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: 17842459

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17842459

Country of ref document: EP

Kind code of ref document: A1

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载