Processing of ammonia and peroxide in liquid streams

Abstract

Methods and related systems for treating ammonia- and hydrogen peroxide-containing streams are provided. Some embodiments relate to decomposing at least some hydrogen peroxide in a first stream that contains both ammonia and hydrogen peroxide. The resulting stream may be treated (e.g., using a stripper and scrubber subsystem) to enrich the ammonia while, in some instances, using the ammonia to at least partially neutralize a second stream that contains sulfuric acid and hydrogen peroxide. The first and / or second stream may contain and / or be derived from semiconductor processing wastewater. The resulting neutralized stream may have a sufficiently high pH for further hydrogen peroxide decomposition. The methods and systems may further produce ammonium sulfate, which may be further concentrated (e.g., to form a solid ammonium sulfate salt).

Description

[0001] PROCESSING OF AMMONIA AND PEROXIDE IN LIQUID STREAMS

[0002] TECHNICAL FIELD

[0003] Methods and related systems for treating ammonia- and hydrogen peroxidecontaining streams are provided.

[0004] SUMMARY

[0005] Methods and related systems for treating ammonia- and hydrogen peroxidecontaining streams are provided. The subject matter of the present invention involves, in some cases, interrelated products, alternative solutions to a particular problem, and / or a plurality of different uses of one or more systems and / or articles.

[0006] Certain aspects relate to a method. In some embodiments, the method comprises exposing an ammonia-containing aqueous input stream comprising ammonia in an amount of greater than or equal to 10 mg / L and hydrogen peroxide in an amount of greater than or equal to 100 mg / L to a first hydrogen peroxide decomposition agent comprising a metal and / or metal oxide and a second hydrogen peroxide decomposition agent comprising an enzyme, such that at least 90 mole percent (mol%) of the hydrogen peroxide of the ammonia-containing aqueous input stream is decomposed, thereby forming a peroxide-diminished ammonia-containing stream; exposing at least some of the ammonia from the peroxide-diminished ammonia-containing stream to a sulfuric acid-containing aqueous input stream comprising sulfuric acid in an amount of greater than or equal to 0.1 M and hydrogen peroxide in an amount of greater than or equal to 100 mg / L, thereby forming a neutralized aqueous stream comprising dissolved ammonium sulfate and hydrogen peroxide, the neutralized aqueous stream having a higher pH than the sulfuric acid-containing aqueous input stream; and exposing at least a portion of the neutralized aqueous stream to a third hydrogen peroxide decomposition agent comprising an enzyme, such that at least 90 mol% of the hydrogen peroxide of the neutralized aqueous stream is decomposed, thereby forming a peroxide-diminished neutralized aqueous stream comprising dissolved ammonium sulfate.

[0007] Some aspects related to water treatment systems. In some embodiments, the water treatment system comprises a stripper vessel comprising: a liquid inlet fluidically connected to a source of an ammonia-containing aqueous input stream comprising ammonia and hydrogen peroxide; a liquid outlet; a gas inlet; and a gas outlet; and a 13190680.1 scrubber vessel comprising: a liquid inlet fluidically connected to a source of a sulfuric acid-containing aqueous input stream comprising sulfuric acid and hydrogen peroxide; a liquid outlet; a gas inlet fluidically connected to the gas outlet of the stripper vessel; and a gas outlet.

[0008] Other advantages and novel features of the present invention will become apparent from the following detailed description of various non-limiting embodiments of the invention when considered in conjunction with the accompanying figures. In cases where the present specification and a document incorporated by reference include conflicting and / or inconsistent disclosure, the present specification shall control.

[0009] BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention. In the figures:

[0011] FIG. 1A is a schematic diagram of an example of a system configured to decompose hydrogen peroxide and expose ammonia to acid, according to some embodiments;

[0012] FIG. IB is a schematic diagram of an example of a system configured to decompose hydrogen peroxide and expose ammonia to acid, according to some embodiments;

[0013] FIG. 2A is a schematic diagram of an example of an ammonia-acid exposure subsystem comprising a stripper vessel and a scrubber vessel, according to some embodiments;

[0014] FIG. 2B is a schematic diagram of an example of an ammonia-acid exposure subsystem comprising a gas-transfer membrane separator, according to some embodiments;

[0015] FIG. 3A is a schematic diagram of an example of a system configured to decompose hydrogen peroxide and expose ammonia to acid and further concentrate

[0016] 13190680.1 ammonium sulfate at least in part via a membrane separator, according to some embodiments;

[0017] FIG. 3B is a schematic diagram of an example of a system configured to decompose hydrogen peroxide and expose ammonia to acid and further concentrate ammonium sulfate at least in part via a membrane separator, according to some embodiments;

[0018] FIG. 3C is a schematic diagram of an example of a system configured to decompose hydrogen peroxide, expose ammonia to acid, further concentrate ammonium sulfate at least in part via a membrane separator, and form solid ammonium sulfate in a solids formation vessel, according to some embodiments;

[0019] FIG. 4A is a schematic illustration of an example of a single-membrane membrane separator, according to some embodiments;

[0020] FIG. 4B is a schematic illustration of an example of a membrane separator comprising multiple semi-permeable membranes fluidically connected in parallel, according to some embodiments; and

[0021] FIG. 4C is a schematic illustration of an example of a membrane separator comprising multiple semi-permeable membranes fluidically connected in series, according to some embodiments.

[0022] DETAILED DESCRIPTION

[0023] Methods and related systems for treating ammonia- and hydrogen peroxidecontaining streams are provided. Some embodiments relate to decomposing at least some hydrogen peroxide in a first stream that contains both ammonia and hydrogen peroxide. The resulting stream may be treated (e.g., using a stripper and scrubber subsystem) to enrich the ammonia while, in some instances, using the ammonia to at least partially neutralize a second stream that contains sulfuric acid and hydrogen peroxide. The first and / or second stream may contain and / or be derived from semiconductor processing wastewater. The resulting neutralized stream may have a pH better suited for further hydrogen peroxide decomposition. The methods and systems may further produce ammonium sulfate, which may be further concentrated (e.g., to form a solid ammonium sulfate salt).

[0024] Certain processes, such as semiconductor processing, produce liquid streams that must be treated for environmental, safety, and / or economic reasons. For example,

[0025] 13190680.1 semiconductor processing facilities may produce wastewater streams containing chemical species such as ammonia and / or sulfuric acid whose removal and / or conversion would be beneficial. One strategy for removing ammonia and sulfuric acid from waste streams is using a stripper / scrubber system in which ammonia is stripped from one waste stream and scrubbed into another stream, where it can react with sulfuric acid to produce dissolved ammonium sulfate. However, it has been realized in the context of this disclosure that hydrogen peroxide (H2O2) may be present in one or both of the ammonia- containing and sulfuric-acid containing streams and may have deleterious effects on the ammonia and / or sulfuric acid processing. Accordingly, systems and methods that treat the hydrogen peroxide in a manner compatible with the underlying ammonia and sulfuric acid-containing stream treatments is desirable. It has been realized in the context of this disclosure that exposure of a stream containing ammonia and hydrogen peroxide to certain hydrogen peroxide decomposition agents may facilitate decomposition of the hydrogen peroxide without disrupting the ammonia and sulfuric acid treatment. Further, it has been found that the underlying ammonia and sulfuric acid treatment can facilitate the hydrogen peroxide removal (e.g., by raising the pH to a level compatible with certain hydrogen peroxide decomposition agents or otherwise making the pH more suitable for the hydrogen peroxide decomposition). Accordingly, the methods and systems of this disclosure provide a synergistic approach to treating liquid streams and, in some instances, efficiently producing a value-added product in ammonium sulfate (e.g., via membrane based liquid separations).

[0026] Methods for treating streams containing ammonia and hydrogen peroxide, and related systems, are generally described. FIGS. 1A-1B and 3A-3C show schematic illustrations of system 100, which is an example of a system in which certain methods described herein may be carried out.

[0027] Some embodiments comprise treating an ammonia-containing aqueous input stream. Referring again to FIGS. 1A-B and 3A-3C, ammonia-containing aqueous input stream 101 may be fed into system 100 for treatment.

[0028] In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, and / or up to 99 wt%, up to 99.9 wt%, or more of the liquid of the ammonia-containing aqueous input stream is water. The ammonia-containing aqueous input stream may comprise ammonia in a relatively large amount. Ammonia is a weak base, so an aqueous solution of ammonia will have both the conjugate base

[0029] 13190680.1 (ammonia molecules, NH3) and conjugate acid (ammonium ions, NH4+) present at the same time (with the relative amount depending on the pH of the ammonia-containing aqueous input stream based on the principles of acid-base chemical equilibria).

[0030] In some embodiments, the ammonia-containing aqueous input stream comprises ammonia in an amount (corresponding to the sum of the amounts of NH3 and NH4+) of greater than or equal to 10 mg / L, greater than or equal to 20 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100 mg / L, greater than or equal to 200 mg / L, greater than or equal to 300 mg / L, and / or up to 400 mg / L, up to 500 mg / L, or more. Combinations of these ranges are possible. As an illustrative example, if the ammonia- containing aqueous input stream comprises ammonia molecules in an amount of 20 mg / L and ammonium ions in an amount of 30 mg / L, the ammonia-containing aqueous input stream in this context would be considered to comprise ammonia in an amount of 50 mg / L (corresponding to the sum of the amounts of NH3 and NH4+).

[0031] In some embodiments, the ammonia-containing aqueous input stream comprises hydrogen peroxide in addition to the ammonia. In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or more (e.g., all) of the liquid of the ammonia-containing aqueous input stream is a combination of water and hydrogen peroxide. The hydrogen peroxide may be present in a relatively high amount (e.g., as the result of the hydrogen peroxide being used as a reagent in an industrial process that produced at least a portion of the ammonia- containing aqueous input stream, such as surface cleaning and / or conditioning in semiconductor processing). In some embodiments, the ammonia-containing aqueous input stream comprises hydrogen peroxide in an amount of greater than or equal to 100 mg / L, greater than or equal to 200 mg / L, greater than or equal to 500 mg / L, greater than or equal to 1,000 mg / L, greater than or equal to 2,000 mg / L, and / or up to 5,000 mg / L, up to 10,000 mg / L, up to 20,000 mg / L, or more. Combinations of these ranges are possible.

[0032] In some embodiments, the ammonia-containing aqueous input stream has a relatively high pH. The high pH may be at least in part due to the presence of the ammonia as a base in the stream. In some embodiments, the ammonia-containing aqueous input stream has a pH of greater than or equal to 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 11, and / or up to 12, up to 13, up to 14, or greater. Combinations of these ranges are possible.

[0033] 13190680.1 The ammonia-containing aqueous input stream may contain or be derived from any of a variety of sources, e.g., that produce streams containing both ammonia and hydrogen peroxide. As mentioned above, in some embodiments the ammonia-containing aqueous input stream is or is derived from a wastewater stream. The wastewater stream may be an effluent from an industrial process (e.g., a manufacturing process and / or chemical or materials synthesis process). In some embodiments, the wastewater stream is a semiconductor processing wastewater stream. Accordingly, some embodiments relate to receiving a semiconductor processing wastewater stream and transporting at least a portion of the semiconductor processing wastewater stream to the water treatment system, forming some or all of the ammonia-containing aqueous input stream. Semiconductor processing facilities include those used to fabricate semiconductor devices. An example of a semiconductor device is a microelectronics device, including, but not limited to, processors such as computer processing units (CPUs), graphical processing units (GPUs), and / or integrated circuits. Semiconductor processing wastewater may contain at least some components (e.g., residual reagents, reaction products, and / or spectator species) that contacted a semiconductor during a semiconductor processing process (e.g., a process for the formation of electronics from silicon semiconductors, III-V semiconductors, and / or other types of semiconductors).

[0034] In some embodiments, at least some of the hydrogen peroxide in the ammonia- containing aqueous input stream is decomposed. It may be desirable in some instances to decompose the hydrogen peroxide because the hydrogen peroxide, as an oxidant, may present an environmental and / or safety risk and / or may adversely affect downstream water treatment processes. The decomposition of hydrogen peroxide may proceed via any of a variety of mechanisms. One such example is the decomposition of hydrogen peroxide to water and oxygen gas as follows:

[0035] In some embodiments, one or more hydrogen peroxide decomposition agents are employed to facilitate the decomposition of the hydrogen peroxide. In some embodiments, the ammonia-containing aqueous input stream is exposed to one or more hydrogen peroxide decomposition agents. In some such embodiments, the ammonia- containing aqueous input stream is exposed to two or more distinct hydrogen peroxide decomposition agents either simultaneously or sequentially. For example, ammonia- containing aqueous input stream 101 may be exposed to a first hydrogen peroxide

[0036] 13190680.1 decomposition agent and a second, different hydrogen peroxide decomposition agent. Referring back to system 100 in FIGS. 1A-1B, and 3A-3C, ammonia-containing aqueous input stream 101 may be exposed to a first hydrogen peroxide decomposition agent from stream 102 and to a second hydrogen peroxide decomposition agent from stream 103. The ammonia-containing aqueous input stream may be exposed to the first and / or second hydrogen peroxide decomposition agent in any of a variety of manners. For example, the ammonia-containing aqueous input stream and the first and / or second hydrogen peroxide decomposition agents may be fed to one or more reactor vessels (e.g., a batch, semi-batch, or continuous reactor vessel) and subsequently mixed. In some embodiments, the first and / or second hydrogen peroxide decomposition agent is in a solid form when exposed to the ammonia-containing aqueous input stream. In some embodiments, the first and / or second hydrogen peroxide decomposition agent is in a liquid form when exposed to the ammonia-containing aqueous input stream (e.g., as a solute in a liquid stream that is mixed with the ammonia-containing aqueous input stream).

[0037] As noted above, in some embodiments the first hydrogen peroxide decomposition agent and second hydrogen peroxide decomposition agent are exposed to the ammonia- containing aqueous input stream sequentially. For example, in some embodiments, at least a portion of the exposure of the ammonia-containing aqueous input stream to the first hydrogen peroxide decomposition agent is performed prior to any exposure of the ammonia-containing aqueous input stream to the second hydrogen peroxide decomposition agent. It should be understood that the use of “first” and “second” in this context is to differentiate the different hydrogen peroxide decomposition agents, and the reverse order may be possible in some embodiments (e.g., at least a portion of the exposure of the ammonia-containing aqueous input stream to the second hydrogen peroxide decomposition agent may be performed prior to any exposure of the ammonia- containing aqueous input stream to the first hydrogen peroxide decomposition agent).

[0038] In some embodiments, the exposure of at least some of the first hydrogen peroxide decomposition agent to the ammonia-containing aqueous input stream occurs simultaneously with the exposure of at least some of the second hydrogen peroxide decomposition agent to the ammonia-containing aqueous input stream.

[0039] Any of a variety of hydrogen peroxide decomposition agents may be employed, depending on, for example, the pH of the ammonia-containing aqueous input stream

[0040] 13190680.1 and / or the presence of other species within the stream (e.g., which may affect chemical compatibility). In some embodiments, the first hydrogen peroxide decomposition agent and / or the second hydrogen peroxide decomposition agent is a catalyst for hydrogen peroxide decomposition. In some embodiments, the first hydrogen peroxide decomposition agent comprises a metal and / or metal oxide. Examples of metal and / or metal oxides that may be employed to facilitate hydrogen peroxide decomposition (e.g., as a hydrogen decomposition catalyst) include, but are not limited to silver metal, a silver oxide, copper metal, a copper oxide, iron metal, an iron oxide, nickel metal, a nickel oxide, manganese metal, a manganese oxide, platinum metal, a platinum oxide, zirconium metal, and / or a zirconium oxide. As one specific example, the first hydrogen peroxide decomposition agent may comprise manganese dioxide (MnCE). In some embodiments, the second hydrogen peroxide decomposition agent comprises an enzyme. Examples of enzymes that may be employed to facilitate hydrogen peroxide decomposition (e.g., as a hydrogen peroxide decomposition catalyst) include catalase and / or a peroxidase. It has been realized in the context of this disclosure that employing a first hydrogen peroxide decomposition agent and a second, different hydrogen peroxide decomposition agent may promote more effective and / or practical hydrogen peroxide decomposition under the conditions of the method than using a single hydrogen peroxide decomposition agent. For example, in some embodiments, such as some in which hydrogen peroxide is present in the ammonia-containing aqueous input stream at a relatively high amount, use of only an enzyme hydrogen peroxide decomposition agent would be impractical as the required loadings of enzyme might be cost-prohibitive and / or lead to poor performance (e.g., due to protein aggregation and / or denaturing). However, use of a metal and / or metal oxide hydrogen peroxide decomposition agent in addition to the enzyme hydrogen peroxide decomposition agent may lower the amount of enzyme needed for adequate hydrogen peroxide decomposition. Additionally, by lowering the amount of enzyme in the streams, the resulting total organic carbon (TOC) may be lowered, which can reduce the extent or need for further processing of the resulting streams to reduce TOC downstream of the hydrogen peroxide decomposition process. It has also been observed that a combination of an enzyme-based hydrogen peroxide decomposition agent and a metal and / or metal oxide-based hydrogen peroxide decomposition agent can lead to more effective decomposition of hydrogen peroxide than when either type of hydrogen peroxide decomposition agent is used alone. Such an

[0041] 13190680.1 increased effectiveness may be helpful in instances where hydrogen peroxide is present at relatively high concentrations (e.g., greater than or equal to 1,000 mg / L, greater than or equal to 2,000 mg / L, or more). Yet another advantage is that the use of enzymes can significantly benefit the amount of metal catalyst that must be used; these are, in some embodiments, added at 1:1 to a 1:1.5 stoichiometric ratio of H2O2 to catalyst, so without enzymes, the dosage would be very high.

[0042] Any of a variety of dosages of the first hydrogen peroxide decomposition agent and the second hydrogen peroxide decomposition agent may be used, provided that a sufficient amount of the first hydrogen peroxide decomposition agent and the second hydrogen peroxide decomposition agent is present to facilitate the desired hydrogen peroxide decomposition. In some embodiments, the enzyme dosage is greater than or equal to 2 parts per million (ppm) or greater than or equal to 5 ppm (on a mass basis). In some embodiments, the enzyme dosage is less than or equal to 4000 ppm or less than or equal to 100 ppm (on a mass basis). Combinations of these ranges are possible (e.g., 2 - 4,000 ppm, or 5-100 ppm).

[0043] In some embodiments, metal catalyst is added to establish a stoichiometric ratio of 1:1 - 1:1.5 of H2O2 remaining after enzyme addition to metal catalyst.

[0044] The exposure of the ammonia-containing aqueous input stream to one or more hydrogen peroxide decomposition agents (e.g., the first hydrogen peroxide decomposition agent and / or the second hydrogen peroxide decomposition agent) may be performed (e.g., in terms of quantity / type of agent, duration of exposure, and / or temperature) such that a relatively high percentage of the hydrogen peroxide is decomposed. For example, in some embodiments, the ammonia-containing aqueous input stream is exposed to one or more hydrogen peroxide decomposition agents (e.g., the first hydrogen peroxide decomposition agent and / or the second hydrogen peroxide decomposition agent) such that at least 90 mole percent (mol%), at least 95 mol%, at least 98 mol%, at least 99 mol%, at least 99.9 mol%, at least 99.99 mol%, or more (e.g., all) of the hydrogen peroxide in the ammonia-containing aqueous input stream is decomposed.

[0045] The decomposition of the hydrogen peroxide in the ammonia-containing aqueous input stream may lead to the formation of a peroxide-diminished ammonia-containing stream. For example, referring back to system 100 in FIGS. 1A-1B and 3A-3C, exposure of ammonia-containing aqueous input stream 101 to the first hydrogen

[0046] 13190680.1 peroxide decomposition agent in stream 102 and the second hydrogen peroxide decomposition agent in stream 103 may lead to the formation of some or all of peroxidediminished ammonia-containing stream 104. The term “peroxide-diminished ammonia- containing stream” is used for convenience in identifying the stream and its relative amount of hydrogen peroxide compared to the ammonia-containing aqueous input stream; the term is not intended to imply any specific absolute concentration of hydrogen peroxide. In some embodiments, hydrogen peroxide is present in the peroxidediminished ammonia-containing stream in an amount of less than or equal to 1,000 mg / L, less than or equal to 500 mg / L, less than or equal to 200 mg / L, less than or equal to 100 mg / L, less than or equal to 50 mg / L, less than or equal to 20 mg / L, less than or equal to 10 mg / L, less than or equal to 1 mg / L, and / or as low as 0.1 mg / L, as low as 0.01 mg / L, or lower (e.g., 0 mg / L). Combinations of these ranges are possible.

[0047] Some embodiments comprise treating a sulfuric acid-containing aqueous input stream. Referring again to FIGS. 1A-B and 3A-3C, sulfuric acid-containing aqueous input stream 105 may be fed into system 100 for treatment.

[0048] In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, and / or up to 99 wt%, up to 99.9 wt%, or more of the liquid of the sulfuric acid-containing aqueous input stream is water. The sulfuric acid-containing aqueous input stream may comprise sulfuric acid (H2SO4) in a relatively large amount. Sulfuric acid is a strong base, so an aqueous solution of sulfuric acid will typically contain the conjugate bases (hydrogen sulfate (HSO4') and sulfate ions (SO42'))and protons dissociated from the sulfuric acid (e.g., typically forming hydronium ions, H3O+).

[0049] In some embodiments, the sulfuric acid-containing aqueous input stream comprises sulfuric acid in an amount (corresponding to the sum of the amounts of H2SO4, HSO4', and SO42') of greater than or equal to 0.1 M, greater than or equal to 0.2 M, greater than or equal to 0.5 M, greater than or equal to 1 M, greater than or equal to 2 M, and / or up to 3 M, up to 4 M, up to 5 M, or more. Combinations of these ranges are possible. As an illustrative example, if the sulfuric-containing aqueous input stream comprises H2SO4 molecules in an amount of 0.000001 M, HSO4' ions in an amount of 0.09 M, and SO42' ions in an amount of 0.01 M, the sulfuric acid-containing aqueous input stream in this context would be considered to comprise sulfuric acid in an amount

[0050] 13190680.1 of 0.1 M (corresponding to the sum of the amounts of H2SO4, HSO4', and SO42' rounded to a single significant digit).

[0051] In some embodiments, the sulfuric acid-containing aqueous input stream comprises hydrogen peroxide in addition to the sulfuric acid. In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or more (e.g., all) of the liquid of the sulfuric acid-containing aqueous input stream is a combination of water and hydrogen peroxide. The hydrogen peroxide may be present in a relatively high amount (e.g., as the result of the hydrogen peroxide being used as a reagent in an industrial process that produced at least a portion of the sulfuric acid-containing aqueous input stream, such as surface cleaning and / or conditioning in semiconductor processing). In some embodiments, the sulfuric acidcontaining aqueous input stream comprises hydrogen peroxide in an amount of greater than or equal to 100 mg / L, greater than or equal to 200 mg / L, greater than or equal to 500 mg / L, greater than or equal to 1,000 mg / L, greater than or equal to 2,000 mg / L, and / or up to 5,000 mg / L, up to 10,000 mg / L, up to 20,000 mg / L, or more. Combinations of these ranges are possible.

[0052] In some embodiments, the ammonia-containing aqueous input stream has a relatively low pH. The low pH may be at least in part due to the presence of the sulfuric acid as an acid in the stream. In some embodiments, the sulfuric acid-containing aqueous input stream has a pH of less than 7, less than or equal to 6, less than or equal to 5, less than or equal to 4, less than or equal to 3, less than or equal to 2, and / or as low as 1, as low as 0, as low as -1, or lower. Combinations of these ranges are possible.

[0053] The sulfuric acid-containing aqueous input stream may contain or be derived from any of a variety of sources, e.g., that produce streams containing both sulfuric acid and hydrogen peroxide. As mentioned above, in some embodiments, the sulfuric acidcontaining aqueous input stream is or is derived from a wastewater stream. The wastewater stream may be an effluent from an industrial process (e.g., a manufacturing process and / or chemical or materials synthesis process). In some embodiments, the wastewater stream is a semiconductor processing wastewater stream. Accordingly, some embodiments relate to receiving a semiconductor processing waste water stream and transporting at least a portion of the semiconductor processing wastewater stream, forming some or all of the sulfuric acid-containing aqueous input stream. In some embodiments where both the ammonia-containing aqueous input stream and the sulfuric

[0054] 13190680.1 acid-containing aqueous input stream contain liquid (e.g., wastewater) produced by an industrial process and / or industrial facility, the same or different industrial process and / or industrial facility produces the liquid for the ammonia-containing aqueous input stream and the liquid for the sulfuric acid-containing aqueous input stream.

[0055] In some embodiments, at least some (e.g., at least 10 wt%, at least 25 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or all) of the ammonia from the peroxide-diminished ammonia-containing stream is exposed to the sulfuric acid-containing aqueous input stream. In some such embodiments, the exposure is direct, with at least a portion of the ammonia-containing aqueous input stream contacting the sulfuric acid-containing aqueous input stream (e.g., by mixing within one or more tanks / reactors). However, in other embodiments, at least some of the ammonia from the peroxide-diminished ammonia-containing stream that is exposed to the sulfuric acid-containing aqueous input stream is first removed from the peroxide-diminished ammonia-containing stream. The ammonia removed from the ammonia-containing aqueous input stream may then be transported to and contacted with at least a portion of the sulfuric acid-containing aqueous input stream.

[0056] In some embodiments, the ammonia from the ammonia-containing aqueous input stream is exposed to the sulfuric acid-containing aqueous input stream in an ammonia- acid exposure sub-system. For example, in the embodiments illustrated in FIGS. 1A-1B and 3A-3C, ammonia-acid exposure sub-system 200 receives peroxide-diminished ammonia-containing stream 104 and sulfuric acid-containing aqueous input stream 105 and produces neutralized aqueous stream 106 as an output, with neutralized aqueous stream 106 comprising at least some of the products of the exposure of the ammonia from peroxide-diminished ammonia-containing stream 104 to one or more components of sulfuric acid-containing aqueous input stream 105 within ammonia-acid exposure subsystem 200. Further non-limiting description of certain embodiments of the ammonia- acid exposure sub-system, such as those involving a stripper vessel and / or a scrubber vessel or those involving a gas-transfer membrane system, are provided below.

[0057] The exposure of the ammonia from the ammonia-containing aqueous input stream to the sulfuric acid-containing aqueous input stream may result in the formation of a neutralized aqueous stream comprising dissolved ammonium sulfate and hydrogen peroxide. Some or all of the hydrogen peroxide in the neutralized aqueous stream may

[0058] 13190680.1 be from the sulfuric acid-containing aqueous input stream. The neutralized aqueous stream may have a higher pH than the sulfuric acid-containing aqueous input stream (e.g., by at least 0.5 pH units, at least 1 pH unit, at least 1.5 pH units, at least 2 pH units, at least 3 pH units, at least 4 pH units, at least 5 pH units, at least 6 pH units, and / or up to 7 pH units, up to 8 pH units, up to 9 pH units, or more). The name “neutralized aqueous stream” is used for convenience to refer to the stream, which may have a higher pH than the sulfuric acid-containing aqueous input stream due to the reaction between the base ammonia and the acid sulfuric acid, and is not meant to indicate that the neutralized aqueous stream has any particular absolute pH value.

[0059] In some embodiments, the neutralized aqueous stream has a pH of greater than or equal to 4, greater than or equal to 5, greater than or equal to 6, greater than or equal to 7, and / or up to 8, up to 9, or up to 10. Combinations of these ranges are possible.

[0060] It has been realized in the context of this disclosure that the increase in pH caused by the exposure of the ammonia to the sulfuric acid-containing aqueous input stream may facilitate effective and practical decomposition of at least some of the hydrogen peroxide in the sulfuric acid-containing aqueous input stream. That is because, for example, certain hydrogen peroxide decomposition agents that might be useful in decomposing the hydrogen peroxide in the sulfuric acid-containing aqueous input stream may be more stable and / or more effective (e.g., as catalysts) at pH values higher than that of the sulfuric acid-containing aqueous input stream. As one specific example, enzyme hydrogen peroxide decomposition agents may be ineffective at relatively low pH values and may even denature at such pH values. Further, by using the ammonia to increase the pH of the sulfuric acid-containing aqueous input stream to form the neutralized aqueous stream instead of by using external base (e.g., external sodium hydroxide and / or external sodium bicarbonate), fewer reagents and / or less equipment may be needed for the system, thereby increasing process efficiency and / or cost effectiveness. Even further, the exposure of the ammonia to the sulfuric acid in the sulfuric acid-containing aqueous input stream may produce dissolved ammonium sulfate (NH4SO4) in the neutralized aqueous stream, which may be useful as a value-added product.

[0061] The neutralized aqueous stream may comprise dissolved ammonium sulfate in a relatively high amount. For example, the neutralized aqueous stream may comprise dissolved ammonium sulfate in an amount of greater than or equal to 10 mg / L, greater than or equal to 20 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100

[0062] 13190680.1 mg / L, greater than or equal to 200 mg / L, greater than or equal to 300 mg / L, and / or up to 400 mg / L, up to 500 mg / L, or more. Combinations of these ranges are possible. In some embodiments, the neutralized aqueous stream comprises dissolved ammonium sulfate in an amount of at least 5 wt%, or at least 25 wt%. In some embodiments, the neutralized aqueous stream comprises dissolved ammonium sulfate in an amount of less than or equal to 35 wt%, or less than 30 wt%. Combinations of these ranges are possible (e.g., 5 wt% - 35 wt%, or 25 wt% - 30 wt%).

[0063] As noted above, in some embodiments, at least some of the ammonia from the peroxide-diminished ammonia-containing stream that is exposed to the sulfuric acidcontaining aqueous input stream is first removed from the peroxide-diminished ammonia-containing stream. One way in which the ammonia may be removed and subsequently exposed to the sulfuric acid-containing aqueous input stream is via a gas stream (e.g., air). For example, in some embodiments, at least some of the ammonia is removed at least in part by exposing at least a portion of the peroxide-diminished ammonia-containing stream to an input gas stream, thereby forming an ammonia-laden gas stream. In some such embodiments, at least a portion of the ammonia-laden gas stream is exposed to the sulfuric acid-containing aqueous stream.

[0064] In some embodiments, a stripper vessel and / or a scrubber vessel is employed (e.g., as part of the ammonia-acid exposure sub-system) to transfer ammonia from the peroxide-diminished ammonia-containing stream to the sulfuric acid-containing aqueous input stream via a gas stream. FIG. 2A shows a schematic diagram of an example of such an embodiment, where ammonia-acid exposure sub-system 200A comprises stripper vessel 207 and scrubber vessel 208. Stripper vessel liquid input 201 comprising at least a portion of peroxide-diminished ammonia-containing stream 104 may be transported to stripper vessel 207. Further, input gas 202 may also be transported to stripper vessel 207, such that input gas 202 contacts at least a portion of stripper vessel liquid input 201. Resulting ammonia-laden gas stream 203 and stripper vessel liquid output 204 may each exit stripper vessel 207. Stripper vessel liquid output 204 may comprise an aqueous stream that is free of ammonia or comprises ammonia in an amount that is lower than stripper vessel liquid input 201. Stripper vessel liquid output 204 may be discharged from the system and / or further treated (e.g., in one or more downstream processes). Stripper vessel 207 may be fluidically connected to scrubber vessel 208 such

[0065] 13190680.1 that at least a portion of ammonia-laden gas stream 203 is transported by stripper vessel 207 to scrubber vessel 208.

[0066] Meanwhile, in the embodiment shown in FIG. 2A, scrubber vessel liquid input 205 comprising at least a portion of sulfuric acid-containing aqueous input stream 105 may be transported to scrubber vessel 208, such that at least a portion of ammonia-laden gas stream 203 contacts at least a portion of scrubber vessel liquid input 205, thereby exposing at least a portion of sulfuric acid-containing aqueous input stream 105 to at least some of the ammonia from peroxide-diminished ammonia-containing stream 104. Resulting scrubber vessel gas output 206 and neutralized aqueous stream 106 may each exit scrubber vessel 208. Scrubber vessel gas output 206 may comprise a gaseous stream that is free of ammonia or comprises ammonia at a concentration that is lower than ammonia-laden gas stream 203.

[0067] Any of a variety of stripper vessel configurations may be employed. The stripper vessel may comprise a stripping column and / or stripping tower. In some embodiments, the stripper vessel may comprise an interior volume configured to promote the contact of gas and liquid. For example, the stripper vessel may comprise packing in at least a portion of the interior volume. One example of a potentially suitable packing is polyvinyl chloride (PVC). The packing may facilitate turbulent gas flow and / or enhanced direct contact between the gas input and the stripper vessel liquid input. In some embodiments, the stripper vessel comprises a packed tower. Another example of a stripper vessel configuration is a vessel configured to flow liquid across vertically- arranged trays. The stripper vessel may be configured to operate in a cross-flow configuration or in a counter-current configuration (e.g., with the input gas entering the stripper vessel near the bottom of the vessel and the liquid input entering the stripper vessel near the top of the vessel).

[0068] The stripper vessel may comprise a liquid inlet. The liquid inlet may be fluidically connected to a source of the ammonia-containing aqueous input stream. In such a way, the peroxide-diminished ammonia-containing stream may be transported to the stripper vessel. For example, stripper vessel liquid input 201 comprising at least a portion of peroxide-diminished ammonia-containing stream 104 may be transported to liquid inlet 209 of stripper vessel 207. In some embodiments, the stripper vessel comprises a liquid outlet. For example, stripper vessel 207 comprises liquid outlet 210 configured to output stripper vessel liquid output 204. In some embodiments, the

[0069] 13190680.1 stripper vessel comprises a gas inlet. For example, stripper vessel 207 comprises gas inlet 211 configured to receive input gas 202 (e.g., as an air inlet). In some embodiments, the stripper vessel comprises a gas outlet. For example, stripper vessel 207 comprises gas outlet 212 configured to output ammonia-laden gas stream 203.

[0070] Any of a variety of scrubber vessel configurations may be employed. The scrubber vessel may comprise a scrubbing column and / or scrubbing tower. In some embodiments, the scrubber vessel may comprise an interior volume configured to promote the contact of gas and liquid. For example, the scrubber vessel may comprise packing in at least a portion of the interior volume. One example of a potentially suitable packing is polyvinyl chloride (PVC). The packing may facilitate turbulent gas flow and / or enhanced direct contact between the ammonia-laden gas stream and the scrubber vessel liquid input. In some embodiments, the scrubber vessel comprises a packed tower. Another example of a scrubber vessel configuration is a vessel configured to flow liquid across vertically-arranged trays. The scrubber vessel may be configured to operate in a cross-flow configuration or in a counter-current configuration (e.g., with the ammonia-laden gas stream entering the scrubber vessel near the bottom of the vessel and the liquid input comprising at least a portion of the sulfuric acid-containing aqueous input stream entering the scrubber vessel near the top of the vessel).

[0071] The scrubber vessel may comprise a liquid inlet. The liquid inlet may be fluidically connected to a source of the sulfuric acid-containing aqueous input stream. In such a way, the sulfuric acid-containing aqueous input stream may be transported to the scrubber vessel. For example, scrubber vessel liquid input 205 comprising at least a portion of sulfuric acid-containing aqueous input stream 105 may be transported to liquid inlet 213 of scrubber vessel 208. In some embodiments, the scrubber vessel comprises a liquid outlet. For example, scrubber vessel 208 comprises liquid outlet 216 configured to output neutralized aqueous stream 106. In some embodiments, the scrubber vessel comprises a gas inlet. For example, scrubber vessel 208 comprises gas inlet 214 fluidically connected to gas outlet 212 of stripper vessel 207. Gas inlet 214 of scrubber vessel 208 may therefore be configured to receive some or all of ammonia-laden gas stream 203. In some embodiments, the scrubber vessel comprises a gas outlet. For example, scrubber vessel 208 comprises gas outlet 215 configured to output scrubber vessel gas output 206.

[0072] 13190680.1 Another way in which the ammonia may be removed from the peroxidediminished ammonia-containing stream and subsequently exposed to the sulfuric acidcontaining aqueous input stream is via a gas transfer membrane. For example, in some embodiments, at least some of the ammonia is removed at least in part by (a) transporting a gas-transfer membrane separator retentate input comprising at least a portion of the peroxide-diminished ammonia-containing stream to the retentate side of a gas-transfer membrane separator comprising a gas-transfer membrane and (b) transporting a gas-transfer membrane separator permeate input comprising at least a portion of the sulfuric acid-containing aqueous input stream to the permeate side of the membrane separator (e.g., as a draw stream). At least a portion of the ammonia may permeate through the gas transfer membrane, thereby being transported from the retentate side into at least a portion of the sulfuric acid-containing aqueous input stream on the permeate side, thereby generating the neutralized aqueous stream. The neutralized aqueous stream may then exit the permeate side of the membrane separator as the gastransfer membrane separator permeate output. For example, FIG. 2B shows a schematic diagram of an embodiment in which a gas-transfer membrane separator retentate input in the form of gas-transfer membrane separator retentate input stream 505 comprising at least a portion of the peroxide-diminished ammonia-containing stream 104 is transported to retentate side 503 of gas-transfer membrane separator 502 comprising gas-transfer membrane 509. Further, a gas-transfer membrane separator permeate input in the form of gas-transfer membrane separator permeate input stream 508 comprising at least a portion of sulfuric acid-containing aqueous input stream 105 is transported to permeate side 504 of membrane separator 502 as a draw stream. At least a portion of the ammonia from peroxide-diminished ammonia-containing stream 104 may permeate through gastransfer membrane 509, thereby being transported from retentate side 503 into at least a portion of gas-transfer membrane permeate input stream 508 on permeate side 504, thereby generating a gas-transfer membrane separator permeate output in the form of gas-transfer membrane separator permeate output stream 507 comprising the neutralized aqueous stream. A gas-transfer membrane separator retentate output in the form of gastransfer membrane separator retentate output stream 506 exits retentate side 503 and has a lower concentration of ammonia than gas-transfer membrane separator retentate input stream 505.

[0073] 13190680.1 The gas-transfer membrane separator may be operated in any of a variety of configurations. For example, the gas-transfer membrane separator may be operated in a counter-current configuration in which the gas-transfer membrane separator retentate input and the gas-transfer membrane separator permeate input have primary flow directions that are substantially parallel (e.g., within 10 degrees of parallel, within 5 degrees of parallel, within 2 degrees of parallel, within 1 degree of parallel, or closer) and in opposite directions. Alternatively, the gas-transfer membrane may be operated in a configuration in which the gas-transfer membrane separator retentate input and the gastransfer membrane separator permeate input flow have primary flow directions that are substantially parallel (e.g., within 10 degrees of parallel, within 5 degrees of parallel, within 2 degrees of parallel, within 1 degree of parallel, or closer) and in the same direction.

[0074] It some embodiments, at least some of the hydrogen peroxide in the neutralized aqueous stream is decomposed. As noted above in the context of the ammonia- containing aqueous input stream, it may be desirable in some instances to decompose the hydrogen peroxide because the hydrogen peroxide, as an oxidant, may present an environmental of safety risk and / or may adversely affect downstream water treatment processes. The decomposition of hydrogen peroxide in the neutralized aqueous stream may proceed via the same reactions and / or mechanisms as described above in the context of the ammonia-containing aqueous input stream (e.g., decomposition to water and oxygen gas), or it may proceed via a different reaction and / or mechanism.

[0075] In some embodiments, one or more hydrogen peroxide decomposition agents are employed to facilitate the decomposition of the hydrogen peroxide in the neutralized aqueous stream. In some embodiments, the neutralized aqueous stream is exposed to one or more hydrogen peroxide decomposition agents (e.g., a third hydrogen peroxide decomposition agent). In some such embodiments, the neutralized aqueous stream is exposed to two or more distinct hydrogen peroxide decomposition agents either simultaneously or sequentially. For example, the neutralized aqueous stream may be exposed to a third hydrogen peroxide decomposition agent and a fourth, different hydrogen peroxide decomposition agent. Referring back to system 100 in FIGS. 1A-1B, and 3A-3C, neutralized aqueous stream 106 may be exposed to a third hydrogen peroxide decomposition agent from stream 107, thereby forming peroxide-diminished neutralized aqueous stream 108. FIG. IB and FIG. 3B show examples of embodiments

[0076] 13190680.1 where a fourth hydrogen peroxide decomposition agent from stream 109 is further exposed to neutralized aqueous stream 106 in forming peroxide-diminished neutralized aqueous stream 108. The neutralized aqueous stream may be exposed to the third and / or fourth hydrogen peroxide decomposition agent in any of a variety of manners. For example, the neutralized aqueous stream and the third and / or fourth hydrogen peroxide decomposition agents may be fed to one or more reactor vessels (e.g., a batch, semibatch, or continuous reactor vessel) and subsequently mixed. In some embodiments, the third and / or fourth hydrogen peroxide decomposition agent is in a solid form when exposed to the neutralized aqueous stream. In some embodiments, the third and / or fourth hydrogen peroxide decomposition agent is in a liquid form when exposed to the neutralized aqueous stream (e.g., as a solute in a liquid stream that is mixed with the neutralized aqueous stream).

[0077] As noted above, in some embodiments the third hydrogen peroxide decomposition agent and fourth hydrogen peroxide decomposition agent are exposed to the neutralized aqueous stream sequentially. For example, in some embodiments, at least a portion of the exposure of the neutralized aqueous stream to the third hydrogen peroxide decomposition agent is performed prior to any exposure of the neutralized aqueous stream to the fourth hydrogen peroxide decomposition agent. It should be understood that the use of “third” and “fourth” in this context is to differentiate the different hydrogen peroxide decomposition agents, and the reverse order may be possible in some embodiments (e.g., at least a portion of the exposure of neutralized aqueous stream to the fourth hydrogen peroxide decomposition agent may be performed prior to any exposure of neutralized aqueous stream to the third hydrogen peroxide decomposition agent).

[0078] In some embodiments, the exposure of at least some of the third hydrogen peroxide decomposition agent to the neutralized aqueous stream occurs simultaneously with the exposure of at least some of the fourth hydrogen peroxide decomposition agent to the neutralized aqueous stream.

[0079] Any of a variety of hydrogen peroxide decomposition agents may be employed, depending on, for example, the pH of the neutralized aqueous stream and / or the presence of other species within the stream (e.g., which may affect chemical compatibility). In some embodiments, the third hydrogen peroxide decomposition agent and / or fourth hydrogen peroxide decomposition agent is a catalyst for hydrogen peroxide

[0080] 13190680.1 decompo sition. In some embodiments, the third hydrogen peroxide decomposition agent comprises an enzyme. As noted above, examples of enzymes that may be employed to facilitate hydrogen peroxide decomposition (e.g., as a hydrogen peroxide decomposition catalyst) include catalase and / or a peroxidase. In some embodiments in which a fourth hydrogen peroxide decomposition agent is employed, the fourth hydrogen peroxide decomposition agent comprises a metal and / or metal oxide. Examples of metal and / or metal oxides that may be employed to facilitate hydrogen peroxide decomposition (e.g., as a hydrogen decomposition catalyst) include, but are not limited to silver metal, a silver oxide, copper metal, a copper oxide, iron metal, an iron oxide, nickel metal, a nickel oxide, manganese metal, a manganese oxide, platinum metal, a platinum oxide, zirconium metal, and / or a zirconium oxide. As one specific example, the fourth hydrogen peroxide decomposition agent may comprise manganese dioxide (MnCh). It has been realized in the context of this disclosure that employing a third hydrogen peroxide decomposition agent and a fourth, different hydrogen peroxide decomposition agent may promote more effective and / or practical hydrogen peroxide decomposition under the conditions of the method than using a single hydrogen peroxide decomposition agent. For example, in some embodiments, such as some in which hydrogen peroxide is present in the neutralized aqueous stream at a relatively high amount, use of only an enzyme hydrogen peroxide decomposition agent would be impractical as the required loadings of enzyme might be expensive and / or lead to poor performance (e.g., due to protein aggregation and / or denaturing). However, use of a metal and / or metal oxide hydrogen peroxide decomposition agent in addition to the enzyme hydrogen peroxide decomposition agent may lower the amount of enzyme needed for adequate hydrogen peroxide decomposition. As also noted above, the increase in the pH of the neutralized aqueous stream as a result of the at least partial neutralization from the contact of the sulfuric acid-containing aqueous input stream with the ammonia may facilitate the use of certain hydrogen peroxide decomposition agents, such as enzyme hydrogen peroxide decomposition agents that would otherwise be inactive and / or unstable at the pH of the sulfuric acid-containing aqueous input stream.

[0081] Any of a variety of dosages of the third hydrogen peroxide decomposition agent and the fourth hydrogen peroxide decomposition agent may be used, provided that a sufficient amount of the first hydrogen peroxide decomposition agent and the second hydrogen peroxide decomposition agent is present to facilitate the desired hydrogen

[0082] 13190680.1 peroxide decomposition. In some embodiments, the enzyme dosage is greater than or equal to 2 parts per million (ppm) or greater than or equal to 5 ppm (on a mass basis). In some embodiments, the enzyme dosage is less than or equal to 4000 ppm or less than or equal to 100 ppm (on a mass basis). Combinations of these ranges are possible (e.g., 2 - 4,000 ppm, or 5-100 ppm). In some embodiments, metal catalyst is added to establish a stoichiometric ratio of 1:1 - 1:1.5 of H2O2 remaining after enzyme addition to metal catalyst.

[0083] The exposure of the neutralized aqueous stream to the one or more hydrogen peroxide decomposition agents (e.g., the third hydrogen peroxide decomposition agent and in some instances the fourth hydrogen peroxide decomposition agent) may be performed (e.g., in terms of quantity / type of agent, duration of exposure, and / or temperature) such that a relatively high percentage of the hydrogen peroxide in the neutralized aqueous stream is decomposed. For example, in some embodiments, the neutralized aqueous stream is exposed to the one or more hydrogen peroxide decomposition agents (e.g., the third hydrogen peroxide decomposition agent and in some instances the fourth hydrogen peroxide decomposition agent) such that at least 90 mole percent (mol%), at least 95 mol%, at least 98 mol%, at least 99 mol%, at least 99.9 mol%, at least 99.99 mol%, or more (e.g., all) of the hydrogen peroxide in the neutralized aqueous stream is decomposed.

[0084] The decomposition of the hydrogen peroxide in the neutralized aqueous stream may lead to the formation of a peroxide-diminished neutralized aqueous stream. The term “peroxide-diminished neutralized aqueous stream” is used for convenience in identifying the stream and its relative amount of hydrogen peroxide compared to the neutralized aqueous stream; the term is not intended to imply any specific absolute concentration of hydrogen peroxide. In some embodiments, hydrogen peroxide is present in the peroxide-diminished neutralized aqueous stream in an amount of less than or equal to 1,000 mg / L, less than or equal to 500 mg / L, less than or equal to 200 mg / L, less than or equal to 100 mg / L, less than or equal to 50 mg / L, less than or equal to 20 mg / L, less than or equal to 10 mg / L, less than or equal to 1 mg / L, and / or as low as 0.1 mg / L, as low as 0.01 mg / L, or lower (e.g., 0 mg / L). Combinations of these ranges are possible.

[0085] The peroxide-diminished neutralized aqueous stream may comprise dissolved ammonium sulfate in a relatively high amount. For example, the peroxide-diminished

[0086] 13190680.1 neutralized aqueous stream may comprise dissolved ammonium sulfate in an amount of greater than or equal to 10 mg / L, greater than or equal to 20 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100 mg / L, greater than or equal to 200 mg / L, greater than or equal to 300 mg / L, and / or up to 400 mg / L, up to 500 mg / L, or more. Combinations of these ranges are possible.

[0087] In some embodiments, the concentration of the dissolved ammonium sulfate in the peroxide-diminished neutralized aqueous stream is increased. The increase in ammonium sulfate concentration may be advantageous in some instances where the ammonium sulfate is desired as a value-added product of the water treatment process and / or where little to no liquid waste streams are desired (e.g., where zero-liquid discharge is desired). The concentration of the dissolved ammonium sulfate may facilitate the obtaining of solid ammonium sulfate. In some embodiments, at least a portion of water from the from the peroxide-diminished neutralized aqueous stream is removed, thereby forming a concentrated ammonium sulfate-containing aqueous stream having a concentration of ammonium sulfate that is greater than that of the peroxidediminished neutralized aqueous stream (e.g., by a factor of greater than or equal to 1.05, greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 3, greater than or equal to 5, greater than or equal to 10, and / or up to 20, up to 50, or greater). Combinations of these ranges are possible (e.g., greater than or equal to 1.5 and less than or equal to 20, or greater than or equal to 2 and less than or equal to 4).

[0088] In some embodiments, the water is removed from the peroxide-diminished neutralized aqueous stream by one or more membrane separators. Accordingly, in some embodiments, a membrane separator retentate output may form some or all of the concentrated ammonium sulfate-containing aqueous stream.

[0089] Some embodiments comprise transporting a membrane separator retentate input (e.g., a membrane separator retentate inlet stream) to a retentate side of a membrane separator. A membrane separator refers to a collection of components including one or more semi-permeable membranes configured to perform a membrane-based separation process (e.g., an osmotic process, a filtration process, or a combination thereof) on an input (e.g., at least one input stream) and produce an output (e.g., at least one output stream). The membrane separator may comprise at least one semi-permeable membrane defining a permeate side of the membrane separator and a retentate side of the membrane

[0090] 13190680.1 separator. Each membrane separator described herein may include further sub-units such as, for example, individual semi-permeable membrane modules (e.g., in the form of cartridges), valving, fluidic conduits, and the like. As described in more detail below, each membrane separator can include a single semi-permeable membrane or multiple semi-permeable membranes. In some embodiments, a single membrane separator can include multiple sub-units (e.g., multiple modules such as multiple cartridges) that may or may not share a common container.

[0091] The retentate side of the membrane separator may be fluidically connected to one or more components of the ammonia-acid exposure sub-system. For example, the retentate side of the membrane separator (e.g., retentate side 303 in FIGS. 3A-3C) may be fluidically connected to the liquid outlet of the scrubber vessel (e.g., liquid outlet 216 in FIG. 2A).

[0092] In association with various embodiments, inputs (e.g., the membrane separator retentate input) and outputs (e.g., the membrane separator permeate output, the membrane separator retentate output) are described. In each case the input and / or output may be in the form of a single stream or multiple streams. In some embodiments, it can be advantageous to use a single stream, as opposed to multiple streams. Thus, in some embodiments, the membrane separator retentate input is in the form of a single stream. In certain embodiments, the membrane separator retentate output is in the form of a single stream. In certain embodiments, the membrane separator permeate output is in the form of a single stream.

[0093] In some embodiments, the membrane separator retentate input comprises at least a portion of the peroxide-diminished neutralized aqueous stream. In some embodiments, the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) (which may comprise at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the peroxide-diminished neutralized aqueous stream, optionally with one or more other streams) is transported to a retentate side of the membrane separator such that a membrane separator retentate output (e.g., a membrane separator retentate output stream) exits the retentate side of the membrane separator, the membrane separator retentate output (e.g., a membrane separator retentate output stream) having a concentration of dissolved ammonium sulfate that is greater (e.g., by a factor of at least 1.03, at least 1.035, at least 1.05, at least 1.10, at least 1.25, at least 1.40, at least 1.50, at

[0094] 13190680.1 least 2, at least 3, at least 4, at least 5, at least 10, and / or up to 20, up to 50, or greater) than the concentration of dissolved ammonium sulfate of the membrane separator retentate input (e.g., a membrane separator retentate inlet stream). For example, referring again to FIGS. 3A-3B, membrane separator 302 may comprise at least one semi-permeable membrane defining retentate side 303 and permeate side 304, and the membrane separator retentate input in the form of membrane retentate inlet stream 305 may be transported to retentate side 303 such that the membrane separator retentate output in the form of membrane separator retentate outlet stream 306 exits retentate side 303. In some embodiments, such as those shown in FIGS. 3A-3B, the membrane separator retentate input in the form of retentate inlet stream 305 comprises at least a portion of peroxide-diminished neutralized aqueous stream 108. This step may be performed such that membrane separator retentate outlet stream 306 has a concentration of dissolved ammonium sulfate that is greater than the concentration of dissolved ammonium sulfate of membrane separator retentate inlet stream 305, according to some embodiments. For example, this step may be performed such that membrane separator retentate outlet stream 306 has a concentration of the ammonium sulfate that is increased with respect to the concentration of membrane separator retentate inlet stream 305 (e.g., by a factor of at least 1.03, at least 1.035, at least 1.05, at least 1.10, at least 1.25, at least 1.40, at least 1.50, at least 2, at least 3, at least 4, at least 5, at least 10, and / or up to 20, up to 50, or greater). In some embodiments, a hydraulic pressure is applied (e.g., to facilitate transport of liquid and / or solute from the retentate side to the permeate side). For example, the hydraulic pressure may be applied the retentate side of the membrane separator during at least a portion of time during which the at least a portion of liquid from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through the semi-permeable membrane of the membrane separator, to the permeate side of the membrane separator. In some embodiments, the system is operated such that the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) has a hydraulic pressure of at least 200 psi (at least 1.38 x 103kPa), at least 500 psi (at least 3.45 x 103kPa), at least 750 psi (at least 5.17 x 103kPa), at least 1000 psi (at least 6.90 x 103kPa), and / or up to 1500 psi (up to 1.03 x 104kPa), up to 2000 psi (up to 1.38 x 104kPa), or more.

[0095] 13190680.1 In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or more) of liquid (e.g., water) from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator. Referring again to FIGS. 3A- 3B, for example, at least a portion of liquid from membrane separator retentate input in the form of membrane separator retentate inlet stream 305 may be transported from retentate side 303, through a semi-permeable membrane, to permeate side 304. Liquid transported from the retentate side to the permeate side of the membrane separator may form some or all of a membrane separator permeate output (e.g., a membrane separator permeate outlet stream) (e.g., membrane separator permeate outlet stream 307 in FIGS. 3A-3B), which may be discharged from the system (e.g., as relatively pure liquid such as relatively pure water).

[0096] In some, but not necessarily all embodiments, a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of ammonium ions and sulfate ions from ammonium sulfate from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi- permeable membrane of the membrane separator, to a permeate side of the membrane separator. However, in some embodiments, little or none (e.g., less than or equal to 10 wt%, less than or equal to 5 wt%, less than or equal to 2 wt%, less than or equal to 1 wt%, less than or equal to 0.1 wt%, or less) of the ammonium ions or sulfate ions from ammonium sulfate from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator.

[0097] In some embodiments, the membrane separator is operated as an osmotic separator. For example, in some embodiments, the semi-permeable membrane is an osmotic membrane. Transport of solvent (e.g., water) through osmotic membrane(s) of membrane separators can be achieved via a transmembrane net driving force (i.e., a net driving force through the thickness of the membrane(s)), according to certain embodiments. Generally, the transmembrane net driving force (A%) is expressed as:

[0098] 13190680.1 AX= AR - A / 7 = (Pi - P2) - ( / 7X- / 72) [1] wherein Pi is the hydraulic pressure on the retentate side of the osmotic membrane, P2 is the hydraulic pressure on the permeate side of the osmotic membrane, III is the osmotic pressure of the stream on the retentate side of the osmotic membrane, and Ih is the osmotic pressure of the stream on the permeate side of the osmotic membrane. (Pi - P2 can be referred to as the transmembrane hydraulic pressure difference, and (Th - Ih can be referred to as the transmembrane osmotic pressure difference.

[0099] The osmotic pressure of a particular liquid is an intrinsic property of the liquid. The osmotic pressure can be determined in a number of ways, with the most efficient method depending upon the type of liquid being analyzed. For certain solutions with relatively low molar concentrations of ions, osmotic pressure can be accurately measured using an osmometer. In other cases, the osmotic pressure can simply be determined by comparison with solutions with known osmotic pressures. For example, to determine the osmotic pressure of an uncharacterized solution, one could apply a known amount of the uncharacterized solution on one side of a non-porous, semi-permeable, osmotic membrane and iteratively apply different solutions with known osmotic pressures on the other side of the osmotic membrane until the differential pressure through the thickness of the membrane is zero.

[0100] The osmotic pressure (IT) of a solution containing n solubilized species may be estimated as: n = ^=1ijMjRT [2] wherein ij is the van’t Hoff factor of the jthsolubilized species, Mj is the molar concentration of the jthsolubilized species in the solution, R is the ideal gas constant, and T is the absolute temperature of the solution. Equation [2] generally provides an accurate estimate of osmotic pressure for liquid with low concentrations of solubilized species (e.g., concentrations at or below between about 4 wt% and about 6 wt%). For many liquids comprising solubilized species, at species concentrations above around 4-6 wt%, the increase in osmotic pressure per increase in salt concentration is greater than linear (e.g., slightly exponential).

[0101] As mentioned above, one type of osmotic separation technique that can be performed using the membrane separators of this disclosure, according to some embodiments, is reverse osmosis. Reverse osmosis generally occurs when the osmotic

[0102] 13190680.1 pressure on the retentate side of the osmotic membrane is greater than the osmotic pressure on the permeate side of the osmotic membrane, and a pressure is applied to the retentate side of the osmotic membrane such that the hydraulic pressure on the retentate side of the osmotic membrane is sufficiently greater than the hydraulic pressure on the permeate side of the osmotic membrane such that the osmotic pressure difference is overcome and liquid (e.g., a solvent such as water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane. Generally, such situations result when the transmembrane hydraulic pressure difference (P1-P2) is greater than the transmembrane osmotic pressure difference (77 / - Ph) such that liquid (e.g., a solvent such as water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane (rather than having liquid be transported from the permeate side of the osmotic membrane to the retentate side of the osmotic membrane, which would be energetically favored in the absence of the pressure applied to the retentate side of the osmotic membrane). In some embodiments, the membrane separator is operated to perform reverse osmosis.

[0103] While FIGS. 3A-3B show a single membrane separator, it should be understood that a different number of membrane separators can be employed in the system and used in the methods of this disclosure. In some embodiments, the membrane separator is a first membrane separator and the system comprises additional membrane separators arranged in series and / or parallel with the first membrane separator. In some embodiments, the system comprises a plurality of membrane separators (e.g., at least two, at least three, at least four, at least five, at least ten, and least twenty, or more membrane separators) configured as described in this disclosure. For example, some embodiments comprise transporting a second membrane separator retentate input (e.g., a second membrane separator retentate inlet stream) to a retentate side of a second membrane separator. The second membrane separator may comprise at least one semi- permeable membrane defining a permeate side of the second membrane separator and a retentate side of the second membrane separator. The second membrane separator retentate input (e.g., a second membrane separator retentate inlet stream) may comprise at least a portion of the first membrane separator retentate output. Moreover, some embodiments comprise transporting a third membrane separator retentate input (e.g., a third membrane separator retentate inlet stream) to a retentate side of a third membrane separator. The third membrane separator may comprise at least one semi-permeable

[0104] 13190680.1 membrane defining a permeate side of the third membrane separator and a retentate side of the third membrane separator. The third membrane separator retentate input (e.g., a membrane separator retentate inlet stream) may comprise at least a portion of the second membrane separator retentate output.

[0105] In some embodiments, a pressure of any of the streams described herein can be increased via one or more additional components, such as one or more booster pumps. In some embodiments, a pressure of any of the streams described herein can be decreased via one or more additional components, such as one or more additional valves and / or energy recovery devices. In some embodiments, a membrane separator described herein further comprises one or more heating, cooling, or other concentration or dilution mechanisms or devices.

[0106] The membrane separators described herein (e.g., the first membrane separator, the second membrane separator, the third membrane separator) can each include a single semi-permeable membrane or a plurality of semi-permeable membranes.

[0107] FIG. 4A is a schematic illustration of membrane separator 400A, in which a single semi-permeable membrane is used to separate permeate side 404 from retentate side 406. Membrane separator 400A can be operated by transporting retentate inlet stream 410 across retentate side 406. At least a portion of a liquid (e.g., a solvent) and, in some instances, solute within retentate inlet stream 410 can be transported across semi-permeable membrane 402 to permeate side 404. This can result in the formation of retentate outlet stream 412, which can include a higher concentration of solute than is contained within retentate inlet stream 410, as well as permeate outlet stream 414. Permeate outlet stream 414 can correspond to the liquid (e.g., solvent) and, in some instances, solute, of retentate inlet stream 410 that was transported from retentate side 406 to permeate side 404.

[0108] In some embodiments, a membrane separator (e.g., the first membrane separator, the second membrane separator, the third membrane separator) comprises a plurality of semi-permeable membranes connected in parallel. One example of such an arrangement is shown in FIG. 4B. In FIG. 4B, membrane separator 400B comprises three semi- permeable membranes 402A, 202B, and 402C arranged in parallel. Retentate inlet stream 410 is split into three sub-streams, with one sub-stream fed to retentate side 406A of semi-permeable membrane 402A, another sub-stream fed to retentate side 406B of semi-permeable membrane 402B, and yet another sub-stream fed to retentate side 406C

[0109] 13190680.1 of semi-permeable membrane 402C. Membrane separator 400B can be operated by transporting the retentate inlet sub-streams across the retentate sides of the semi- permeable membranes. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within retentate inlet stream 410 can be transported across each of semi-permeable membranes 402A, 402B, and 402C to permeate sides 404A, 404B, and 404C, respectively. This can result in the formation of three retentate outlet sub-streams, which can be combined to form retentate outlet stream 412. Retentate outlet stream 412 can include a higher concentration of solute than is contained within retentate inlet stream 410. Permeate outlet stream 414 can also be formed (from three permeate outlet sub-streams). Permeate outlet stream 414 can correspond to the liquid (e.g., solvent), and, in some instances, solute of retentate inlet stream 410 that was transported from retentate sides 406A-406C to permeate sides 404A-404C.

[0110] While FIG. 4B shows three semi-permeable membranes connected in parallel, other embodiments could include 2, 4, 5, or more semi-permeable membranes connected in parallel.

[0111] In some embodiments, a membrane separator (e.g., the first membrane separator, the second membrane separator) comprises a plurality of semi-permeable membranes connected in series. One example of such an arrangement is shown in FIG. 4C. In FIG. 4C, membrane separator 400C comprises three semi-permeable membranes 402A, 402B, and 402C arranged in series. In FIG. 4C, retentate inlet stream 410 is first transported to retentate side 406A of semi-permeable membrane 402A. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within retentate inlet stream 410 can be transported across semi-permeable membrane 402A to permeate side 404A of semi- permeable membrane 402A. This can result in the formation of permeate outlet stream 414 and first intermediate retentate stream 440 that is transported to retentate side 406B of semi-permeable membrane 402B. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within first intermediate retentate stream 440 can be transported across semi-permeable membrane 402B to permeate side 404B of semi- permeable membrane 402B. This can result in the formation of permeate outlet stream 450 and second intermediate retentate stream 441 that is transported to retentate side 406C of semi-permeable membrane 402C. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute within second intermediate retentate stream 441 can be transported across semi-permeable membrane 402C to permeate side 404C of semi-

[0112] 13190680.1 permeable membrane 402C. This can result in the formation of permeate outlet stream 451 and retentate outlet stream 412.

[0113] While FIG. 4C shows three semi-permeable membranes connected in series, other embodiments could include 2, 4, 5, or more semi-permeable membranes connected in series.

[0114] For membrane separators comprising a plurality of semi-permeable membranes, parameters such as rejection percentage, recovery, and salt passage percentage at standard conditions for the membrane separators are calculated by performing a mass balance on the entire membrane separator. This means that all initial retentate streams for the membrane separator would be added and considered together, all final permeate outlet streams for the membrane separator would be added and considered together, and all final retentate outlet streams for the membrane separator would be added and considered together. For example, as mentioned above, in FIG. 4B, membrane separator 400B comprises three semi-permeable membranes 402A, 402B, and 402C arranged in parallel. Accordingly, calculation of the composition of the retentate inlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400B would involve taking measurements of retentate inlet stream 410 prior to it being split into the three inlet sub- streams fed to retentate sides 406 A, 406B, and 406C of semi-permeable membranes 402A, 402B, and 402C, respectively. Similarly, calculation of the composition of the retentate outlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400B would involve taking measurements of retentate outlet stream 412, which is a combination of the three outlet sub- streams from retentate sides 406 A, 406B, and 406C from semi- permeable membranes 402A, 402B, and 402C, respectively. Also similarly, calculation of the composition of the permeate outlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions would involve taking measurements of permeate outlet stream 414, which is a combination of the three outlet sub- streams from permeate sides 404A, 404B, and 404C from semi-permeable membranes 402A, 402B, and 402C, respectively.

[0115] 13190680.1 As another example of the calculation of parameters corresponding to a membrane separator comprising a plurality of semi-permeable membranes, reference is made to membrane separator 400C in FIG. 4C. Membrane separator 400C comprises three semi-permeable membranes 402A, 402B, and 402C arranged in series. Accordingly, calculation of the composition of the retentate inlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400C would involve taking measurements of retentate inlet stream 410 prior to it entering semi-permeable membrane 402A because semi-permeable membrane 402A is the initial semi-permeable membrane in the series. Similarly, calculation of the composition of the retentate outlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400C would involve taking measurements of retentate outlet stream 412 exiting semi-permeable membrane 402C because semi-permeable membrane 402C is the final semi-permeable membrane in the series with respect to the retentate outlet streams, thereby making retentate outlet stream 412 the final retentate outlet stream of membrane separator 400C. Calculation of the composition of the permeate outlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions would involve taking measurements of a combination of permeate outlet streams 414, 450, and 451 exiting semi-permeable membranes 402A, 402B, and 402C respectively. In addition, in some embodiments, a given membrane separator could include multiple semi-permeable membranes connected in parallel as well as multiple semi-permeable membranes connected in series.

[0116] In some embodiments, the membrane separator comprises a plurality of semi- permeable membranes. In some such embodiments, the plurality of semi-permeable membranes within the membrane separator are connected in series. In some such embodiments, the plurality of semi-permeable membranes within the membrane separator are connected in parallel. In certain embodiments, the membrane separator comprises a plurality of membranes a first portion of which are connected in series and another portion of which are connected in parallel.

[0117] As mentioned above, each membrane separator of the system may comprise at least one semi-permeable membrane. In general, a semi-permeable membrane is a

[0118] 13190680.1 barrier that allows some components of a mixture to pass through while blocking at least some of other components (e.g., blocking all of another component, or reducing the relative rate of permeation of another component). For example, a semi-permeable membrane may block some molecules in a liquid solution from passing through while allowing others to pass through. In some instances, a semi-permeable membrane blocks some molecules and permits other molecules to pass through based on their molecular weight and / or charge. As noted above, a semi-permeable membrane can be used for osmotic processes. For example, the semi-permeable membrane may be an osmotic membrane. An osmotic membrane may be capable of producing an osmotic pressure difference between solutions on either side of the membrane upon application of a hydraulic pressure difference across the two sides of the membrane. For example, if an osmotic membrane is placed between two solutions of identical composition such that there is initially no osmotic pressure difference across the membrane, application of a hydraulic pressure difference across the osmotic membrane may allow for transport of components from one side of the membrane to the other such that an osmotic pressure difference across the two sides of the membrane is established. Semi-permeable membranes may also be used for nanofiltration processes. Semi-permeable membranes may be configured for osmotic processes, nanofiltration processes, and / or processes in which separation is achieved based on a combination of nanofiltration and osmotic mechanisms (e.g., based on, for example, the molecular weight cutoff of the membranes, pore sizes of the membranes, the nature of the mixtures to which they are exposed, and a magnitude of applied hydraulic pressure).

[0119] The semi-permeable membrane medium can comprise, for example, a metal, a ceramic, a polymer (e.g., polyamides, polyethylenes, polyesters, poly(tetrafluoroethylene), polysulfones, polycarbonates, polypropylenes, poly(acrylates)), and / or composites or other combinations of these. The semi-permeable membranes generally allow for the selective transport of solvent (e.g., water) through the membrane, where solvent is capable of being transmitted through the membrane while solute (e.g., solubilized species such as solubilized ions) are inhibited from being transported through the membrane. Examples of commercially available semi-permeable membranes that can be used in association with certain of the embodiments described herein include, but are not limited to, those commercially available from Dow Water and Process Solutions (e.g., FilmTec™ membranes), Hydranautics, GE Osmonics, Suez, LG,

[0120] 13190680.1 Toyobo, Microdyn, and Toray Membrane, among others known to those of ordinary skill in the art.

[0121] In some embodiments, the semi-permeable membrane of a membrane separator of this disclosure has an average molecular weight cutoff (MWCO) that is sufficiently high such that a desired amount of liquid and / or solute (and / or type of solute) can pass through during operation of the system. In some embodiments, the semi-permeable membrane(s) of the membrane separator and / or the second membrane separator, has an average MWCO of greater than or equal to 50 Daltons, greater than or equal to 75 Daltons, greater than or equal to 100 Daltons, greater than or equal to 150 Daltons, or greater. In some embodiments, the semi-permeable membrane of a membrane separator of this disclosure has an average molecular weight cutoff (MWCO) that is sufficiently low such that a desired amount of solute (and / or type of solute) is rejected such that an effective separation is performed. In some embodiments, the semi-permeable membrane(s) of the membrane separator and / or the second membrane separator has an average MWCO of less than or equal to 400 Daltons, less than or equal to 300 Daltons, less than or equal to 250 Daltons, less than or equal to 200 Daltons, or less. Combinations of these ranges (e.g., greater than or equal to 50 Daltons and less than or equal to 400 Daltons, greater than or equal to 50 Daltons and less than or equal to 250 Daltons) are possible. The average MWCO of a membrane refers to the lowest molecular weight solute in which 90% of the solute is retained by the membrane.

[0122] The average MWCO of the semi-permeable membrane may affect any of a variety of the parameters discussed below, such as solute permeability, salt passage, rejection, and / or recovery.

[0123] The solute (e.g., ammonium sulfate) permeability of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., solute concentration of incoming influent). The solute permeability of a membrane separator can be calculated from the solute flux through the membrane and the respective concentrations of solute on either side using equation [3] below:

[0124] JS = B(CR- CP) [3]

[0125] In the above equation, Jsrepresents the ion flux, CR represents the concentration of solute on the retentate side of the membrane, Cp represents the concentration of solute on the permeate side of the membrane, and B represents the solute permeability. Solute

[0126] 13190680.1 permeability is dependent on the species of solute in the retentate inlet stream and the concentrations on either side of the membrane.

[0127] In some embodiments in which multiple membrane separators are employed, the solute permeabilities of the membrane separator and the second membrane separator (and, if present a third membrane separator, a fourth membrane separator, or more) during operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams.

[0128] Water permeability can be calculated from the water flux, pressure differential and osmotic differential, as shown below in equation [4]:

[0129] Jw = A(AP - An) [4]

[0130] In the above equation [4], Jwrepresents the flux of water through the membrane, AP represents the hydraulic pressure differential across the membrane, An represents the osmotic pressure differential across the membrane, and A represents the water permeability.

[0131] The salt passage percentage at standard conditions of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., concentration of incoming influent). The salt passage percentage at standard conditions of a membrane separator is an intrinsic property of the separator based on the quantity of salt, as a percentage, which passes through the semi-permeable membrane(s) from the retentate side to the permeate side of the membrane separator under defined reference conditions. The salt passage percentage at standard conditions of a membrane separator can be determined using the standardized test described in ASTM D4516-19a.

[0132] In some embodiments in which multiple membrane separators are employed, the salt passages at standard conditions of the first membrane separator and the second membrane separator (and, if present a third membrane separator, a fourth membrane separator, or more) used in in the operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams. In some embodiments, the salt passage percentage at standard conditions of the first membrane separator and / or the second membrane separator membrane separator are independently greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to

[0133] 13190680.1 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, and / or up to 80%, up to 85%, up to 90%, or greater. In some embodiments, the membrane separator has a relatively low salt passage percentage at standard conditions. Such a low salt passage percentage at standard conditions may be useful in embodiments in which the membrane separator is operated as a high-rejection reverse osmosis separator. In some embodiments, the membrane separator has a salt passage percentage at standard conditions of less than or equal to 10%, less than or equal to 5%, less than or equal to 2%, less than or equal to 1%, less than or equal to 0.1%, or less.

[0134] Intrinsic properties of a semi-permeable membrane such as salt passage percentage at standard conditions and / or MWCO can be selected based on supplier specifications for commercially-obtained membranes, by controlling the synthesis of membranes, and / or by physically and / or chemically modifying existing membranes (e.g., commercially obtained membranes).

[0135] The rejection of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., solute concentration of incoming influent). The rejection, R, of a membrane separator can be calculated from CR (the concentration of solute on the retentate side of the membrane) and Cp (the concentration of solute on the permeate side of the membrane) and expressed as a percentage using Equation [5] below:

[0136] R = [1 - (Cp / CR)] * 100 [5]

[0137] In some embodiments in which multiple membrane separators are employed, the rejections (7?) of the first membrane separator and the second membrane separator (and, if present the third membrane separator, the fourth membrane separator, or more) during operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams.

[0138] In some embodiments, the rejection for at least one solute (e.g., ammonium sulfate, or all solutes) (e.g., the solute during the step of transporting the membrane separator retentate input to the retentate side of the membrane separator) of the membrane separator is greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, greater

[0139] 13190680.1 than or equal to 80%, greater than or equal to 85%, greater than or equal to 90%, greater than or equal to 95%, greater than or equal to 98%, greater than or equal to 99%, greater than or equal to 99.9%, or greater. In some embodiments, the rejection for at least one solute (e.g., ammonium sulfate, or all solutes) (e.g., the solute during the step of transporting the membrane separator retentate input to the retentate side of the membrane separator) of the membrane separator is less than or equal to 100%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 75%, less than or equal to 60%, less than or equal to 50%, or less. Combinations of these ranges (e.g., greater than or equal to 10% and less than or equal to 100%) are possible.

[0140] In some embodiments, solid ammonium sulfate is formed from at least a portion of the dissolved ammonium salt in the concentrated ammonium sulfate-containing aqueous stream. The solid ammonium sulfate may be formed in a solids formation vessel. For example, referring to FIG. 3C, solids formation vessel 309 may have a liquid inlet fluidically connected to retentate side 303 of membrane separator 302 such that at least a portion of concentrated ammonium sulfate-containing aqueous stream 308 (which comprises at least a portion of membrane separator retentate outlet stream 306) is transported to solids formation vessel 309.

[0141] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the solid ammonium sulfate is formed via precipitation from the concentrated ammonium sulfate-containing aqueous stream (or a stream comprising at least a portion of the concentrated ammonium sulfate-containing aqueous stream). In some embodiments, the solid ammonium sulfate is formed via crystallization from the concentrated ammonium sulfate-containing aqueous stream (or a stream comprising at least a portion of the concentrated ammonium sulfate-containing aqueous stream stream).

[0142] The solids formation vessel may comprise one or more vessels for receiving at least a portion of a liquid stream (e.g., via a liquid inlet). In some embodiments, the solids formation vessel comprises a cooling apparatus in thermal communication with the vessel (e.g., for lowering a temperature of a liquid within the vessel). In some embodiments, the solids formation vessel comprises a precipitation unit configured to induce precipitation (e.g., amorphous precipitation and / or crystallization). In some embodiments, the solids formation vessel comprises a crystallizer. Examples of

[0143] 13190680.1 apparatuses suitable for solid ammonium sulfate production (e.g., via precipitation) include, but are not limited to, forced circulation evaporators, solvent extraction apparatuses, froth flotation devices, electrodialysis devices, and low-temperature eutectic freeze crystallization apparatuses.

[0144] As used herein, two elements are in fluidic communication with each other (or, equivalently, in fluid communication with each other) when fluid may be transported from one of the elements to the other of the elements without otherwise altering the configurations of the elements or a configuration of an element between them (such as a valve). Two conduits connected by an open valve (thus allowing for the flow of fluid between the two conduits) are considered to be in fluidic communication with each other. In contrast, two conduits separated by a closed valve (thus preventing the flow of fluid between the conduits) are not considered to be in fluidic communication with each other.

[0145] As used herein, two elements are fluidically connected to each other when they are connected such that, under at least one configuration of the elements and any intervening elements, the two elements are in fluidic communication with each other. Two membrane separators connected by a valve and conduits that permit flow between the membrane separators in at least one configuration of the valve would be said to be fluidically connected to each other. To further illustrate, two membrane separators that are connected by a valve and conduits that permit flow between the membrane separators in a first valve configuration but not a second valve configuration are considered to be fluidically connected to each other both when the valve is in the first configuration and when the valve is in the second configuration. In contrast, two membrane separators that are not connected to each other (e.g., by a valve, another conduit, or another component) in a way that would permit fluid to be transported between them under any configuration would not be said to be fluidically connected to each other. Elements that are in fluidic communication with each other are always fluidically connected to each other, but not all elements that are fluidically connected to each other are necessarily in fluidic communication with each other.

[0146] Various components are described herein as being fluidically connected. Fluidic connections may be either direct fluidic connections or indirect fluidic connections. Generally, a direct fluidic connection exists between a first region and a second region (and the two regions are said to be directly fluidically connected to each other) when

[0147] 13190680.1 they are fluidically connected to each other and when the composition of the fluid at the second region of the fluidic connection has not substantially changed relative to the composition of the fluid at the first region of the fluidic connection (i.e., no fluid component that was present in the first region of the fluidic connection is present in a weight percentage in the second region of the fluidic connection that is more than 5% different from the weight percentage of that component in the first region of the fluidic connection). As an illustrative example, a stream that connects first and second unit operations, and in which the pressure and temperature of the fluid is adjusted but the composition of the fluid is not altered, would be said to directly fluidically connect the first and second unit operations. If, on the other hand, a separation step is performed and / or a chemical reaction is performed that substantially alters the composition of the stream contents during passage from the first component to the second component, the stream would not be said to directly fluidically connect the first and second unit operations. In some embodiments, a direct fluidic connection between a first region and a second region can be configured such that the fluid does not undergo a phase change from the first region to the second region. In some embodiments, the direct fluidic connection can be configured such that at least 50 wt% (or at least 75 wt%, at least 90 wt%, at least 95 wt%, or at least 98 wt%) of the fluid (e.g., liquid) in the first region is transported to the second region via the direct fluidic connection. Any of the fluidic connections described herein may be, in some embodiments, direct fluidic connections. In other cases, the fluidic connections may be indirect fluidic connections.

[0148] The following applications are incorporated herein by reference, in their entirety, for all purposes: U.S. Patent Application Publication No. US 2015 / 0060286 published on March 5, 2015, filed as U.S. Patent Application No. 14 / 452,387 on August 5, 2014, and entitled “WATER TREATMENT SYSTEMS AND ASSOCIATED METHODS”; U.S. Patent Application Publication No. US 2015 / 0129410 published on May 14, 2015, filed as U.S. Patent Application No. 14 / 485,606 on September 12, 2014, and entitled “SYSTEMS INCLUDING A CONDENSING APPARATUS SUCH AS A BUBBLE COLUMN CONDENSER”; U.S. Patent Application Publication No. US 2015 / 0083577 published on March 26, 2015, filed as U.S. Application No. 14 / 494,101 on September 23, 2014, and entitled “DESALINATION SYSTEMS AND ASSOCIATED METHODS”; U.S. Patent Application Publication No. US 2016 / 0228795 published on August 11, 2016, filed as U.S. Patent Application No. 14 / 719,295 on May 21, 2015, and

[0149] 13190680.1 entitled “METHODS AND SYSTEMS FOR PRODUCING TREATED BRINES”; U.S. Patent Application Publication No. US 2019 / 0009218 published on January 10, 2019, filed as U.S. Patent Application No. 15 / 747,907 on January 26, 2018, and entitled “OSMOTIC DESALINATION METHODS AND ASSOCIATED SYSTEMS”; U.S. Patent Application Publication No. US 2017 / 0144906 published on May 25, 2017, filed as U.S. Patent Application No. 15 / 364,785 on November 30, 2016, and entitled “SYSTEMS AND METHODS FOR TREATMENT OF WATER, SUCH AS OILFIELD WASTEWATER, VIA CHEMICAL COAGULATION”; U.S. Patent Application Publication No. US 2021 / 0179452 published on June 17, 2021, filed as U.S. Patent Application No. 17 / 270,142 on February 22, 2021, and entitled “LIQUID SOLUTION CONCENTRATION SYSTEM COMPRISING ISOLATED SUBSYSTEM AND RELATED METHODS”; U.S. Patent Application Publication No. US 2022 / 0380233 published on December 1, 2022, filed as U.S. Patent Application No. 17 / 882,701 on August 8, 2022, and entitled “OSMOTIC METHODS AND SYSTEMS INVOLVING ENERGY RECOVERY”; U.S. Patent Application Publication No. US 2024 / 0109037 published on April 4, 2024, filed as U.S. Patent Application No. 18 / 315,130 on May 10, 2023, and entitled “LIQUID SEPARATION USING SOLUTE-PERMEABLE MEMBRANES AND RELATED SYSTEMS”; and U.S. Patent Application Publication No. 2023 / 0001355, published on January 5, 2023, filed as U.S. Patent Application No. 17 / 305,289 on July 2, 2021, and entitled “MEMBRANES WITH CONTROLLED POROSITY FOR SERIAL FILTRATION”.

[0150] While several embodiments of the present invention have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and / or structures for performing the functions and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is deemed to be within the scope of the present invention. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the teachings of the present invention is / are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. It is, therefore, to be understood that the foregoing embodiments are

[0151] 13190680.1 presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, and / or methods, if such features, systems, articles, materials, and / or methods are not mutually inconsistent, is included within the scope of the present invention.

[0152] As used herein in the specification and in the claims, the phrase “at least a portion” means some or all. “At least a portion” may mean, in accordance with certain embodiments, at least 1 wt%, at least 2 wt%, at least 5 wt%, at least 10 wt%, at least 25 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt%, and / or, in certain embodiments, up to 100 wt%.

[0153] The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0154] The phrase “and / or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and / or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0155] As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives

[0156] 13190680.1 (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0157] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and / or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0158] Unless clearly indicated to the contrary, concentrations and percentages described herein are on a mass basis.

[0159] As used herein, “wt%” is an abbreviation of weight percentage. As used herein, “at%” is an abbreviation of atomic percentage.

[0160] Some embodiments may be embodied as a method, of which various examples have been described. The acts performed as part of the methods may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include different (e.g., more or less) acts than those that are described, and / or that may involve performing some acts simultaneously, even though the acts are shown as being performed sequentially in the embodiments specifically described above.

[0161] Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are

[0162] 13190680.1 performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0163] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

[0164] 13190680.1

Claims

1. CLAIMSWhat is claimed is:

1. A method, comprising: exposing an ammonia-containing aqueous input stream comprising ammonia in an amount of greater than or equal to 10 mg / L and hydrogen peroxide in an amount of greater than or equal to 100 mg / L to a first hydrogen peroxide decomposition agent comprising a metal and / or metal oxide and a second hydrogen peroxide decomposition agent comprising an enzyme, such that at least 90 mole percent (mol%) of the hydrogen peroxide of the ammonia-containing aqueous input stream is decomposed, thereby forming a peroxide-diminished ammonia-containing stream; exposing at least some of the ammonia from the peroxide-diminished ammonia- containing stream to a sulfuric acid-containing aqueous input stream comprising sulfuric acid in an amount of greater than or equal to 0.1 M and hydrogen peroxide in an amount of greater than or equal to 100 mg / L, thereby forming a neutralized aqueous stream comprising dissolved ammonium sulfate and hydrogen peroxide, the neutralized aqueous stream having a higher pH than the sulfuric acid-containing aqueous input stream; and exposing at least a portion of the neutralized aqueous stream to a third hydrogen peroxide decomposition agent comprising an enzyme, such that at least 90 mol% of the hydrogen peroxide of the neutralized aqueous stream is decomposed, thereby forming a peroxide-diminished neutralized aqueous stream comprising dissolved ammonium sulfate.

2. The method of claim 1, wherein the metal and / or metal oxide of the first hydrogen peroxide decomposition agent comprises silver metal, a silver oxide, copper metal, a copper oxide, iron metal, an iron oxide, nickel metal, a nickel oxide, manganese metal, a manganese oxide, platinum metal, a platinum oxide, zirconium metal, and / or a zirconium oxide.

3. The method of any one of claims 1-2, wherein the enzyme of the second hydrogen peroxide decomposition agent and / or the third hydrogen peroxide decomposition agent comprises catalase and / or a peroxidase.13191067.

14. The method of any one of claims 1-3, wherein the at least a portion of the neutralized aqueous stream is exposed to a fourth hydrogen peroxide decomposition agent comprising a metal and / or metal oxide in addition to the third hydrogen peroxide decomposition agent.

5. The method of claim 4, wherein the metal and / or metal oxide of the fourth hydrogen peroxide decomposition agent comprises silver metal, a silver oxide, copper metal, a copper oxide, iron metal, an iron oxide, nickel metal, a nickel oxide, manganese metal, a manganese oxide, platinum metal, a platinum oxide, zirconium metal, and / or a zirconium oxide.

6. The method of any one of claims 1-5, wherein at least a portion of the exposing of the ammonia-containing aqueous input stream to the first hydrogen peroxide decomposition agent is performed prior to any of the exposing of the ammonia- containing aqueous input stream to the second hydrogen peroxide decomposition agent.

7. The method of any one of claims 1-6, wherein the at least some of the ammonia from the peroxide-diminished ammonia-containing stream that is exposed to the sulfuric acid-containing aqueous input stream is first removed from the peroxide-diminished ammonia-containing stream.

8. The method of claim 7, wherein the at least some of the ammonia is removed at least in part by exposing at least a portion of the peroxide-diminished ammonia- containing stream to an input gas stream, thereby forming an ammonia-laden gas stream, and at least a portion of the ammonia-laden gas stream is exposed to the sulfuric acidcontaining aqueous stream.

9. The method of claim 8, wherein the at least a portion of the peroxide-diminished ammonia-containing stream is exposed to the input gas stream in a stripper vessel.

10. The method of any one of claims 1-9, wherein the exposing at least some of the ammonia from the peroxide-diminished ammonia-containing stream to the sulfuric acidcontaining aqueous input stream is performed in a scrubber vessel.13191067.

111. The method of any one of claims 1-10, wherein the ammonia-containing aqueous input stream comprises ammonia in an amount of less than or equal to 500 mg / L.

12. The method of any one of claims 1-11, wherein the ammonia-containing aqueous input stream comprises hydrogen peroxide in an amount of less than or equal to 20,000 mg / L.

13. The method of any one of claims 1-12, wherein the sulfuric acid-containing aqueous input stream comprises sulfuric acid in an amount of less than or equal to 5 M.

14. The method of any one of claims 1-13, wherein the sulfuric acid-containing aqueous input stream comprises hydrogen peroxide in an amount of less than or equal to 20,000 mg / L.

15. The method of any one of claims 1-14, wherein the neutralized aqueous stream has a pH of greater than or equal to 4 and less than or equal to 10.

16. The method of any one of claims 1-15, wherein the ammonia-containing aqueous input stream and / or the sulfuric acid-containing aqueous input stream is or is derived from a wastewater stream.

17. The method of claim 16, wherein the wastewater stream is a semiconductor processing waste water stream.

18. The method of any one of claims 1-17, further comprising removing at least a portion of water from the peroxide-diminished neutralized aqueous stream, thereby forming a concentrated ammonium sulfate-containing aqueous stream having a concentration of ammonium sulfate that is greater than that of the peroxide-diminished neutralized aqueous stream.13191067.

119. The method of claim 18, wherein the removing comprises transporting a membrane separator retentate input comprising at least a portion of peroxide-diminished neutralized aqueous stream to a retentate side of a membrane separator such that: a membrane separator retentate output exits the retentate side of the membrane separator, the membrane separator retentate output having a concentration of dissolved ammonium sulfate that is greater than a concentration of dissolved ammonium sulfate in the membrane separator retentate input, and at least a portion of water from the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator.

20. The method of claim 19, wherein the membrane separator retentate input is transported to the retentate side such that a portion of ammonium ions and sulfate ions from dissolved ammonium sulfate in the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator.

21. The method of any one of claims 19-20, wherein the membrane separator has a rejection for ammonium sulfate of less than or equal to 95%.

22. The method of any one of claims 19-21, wherein the membrane separator has a rejection for ammonium sulfate of greater than or equal to 10%.

23. The method of any one of claims 1-22, further comprising forming solid ammonium sulfate salt from at least a portion of the dissolved ammonium salt in the concentrated ammonium sulfate-containing aqueous stream.

24. The method of claim 23, wherein the solid ammonium sulfate salt is formed via crystallization.

25. A water treatment system, comprising: a stripper vessel comprising:13191067.1a liquid inlet fluidically connected to a source of an ammonia-containing aqueous input stream comprising ammonia and hydrogen peroxide; a liquid outlet; a gas inlet; and a gas outlet; and a scrubber vessel comprising: a liquid inlet fluidically connected to a source of a sulfuric acidcontaining aqueous input stream comprising sulfuric acid and hydrogen peroxide; a liquid outlet; a gas inlet fluidically connected to the gas outlet of the stripper vessel; and a gas outlet.

26. The system of claim 25, further comprising a membrane separator comprising at least one semi-permeable membrane defining a retentate side of the membrane separator and a permeate side of the membrane separator, wherein the retentate side of the membrane separator is fluidically connected to the liquid outlet of the scrubber vessel.

27. The system of any one of claims 25-26, further comprising a solids formation vessel comprising a liquid inlet fluidically connected to the retentate side of the membrane separator.

28. The system of claim 27, wherein the solids formation vessel comprises a crystallizer.13191067.1

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