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A method for removing acid-gases from water includes introducing acid into a flow of aqueous solution having acid-gases and associated conjugate bases having an initial pH to lower the pH. The lowered pH solution has a stripping gas passed therethrough, resulting in a vapor phase of liberated acid-g

A method for removing acid-gases from water includes introducing acid into a flow of aqueous solution having acid-gases and associated conjugate bases having an initial pH to lower the pH. The lowered pH solution has a stripping gas passed therethrough, resulting in a vapor phase of liberated acid-gas and stripping gas vapors, and a liquid phase comprising a lower concentration of acid-gases and associated conjugate bases than the aqueous solution. The liberated acid-gas and stripping gas vapors are collected and treated to remove acid-gas components, resulting in clean stripping gas product. The liquid phase is separated and collected with a second treating step, resulting in a final aqueous product having a lower concentration of acid-gases and associated conjugate bases than the liquid phase.

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1. A method for removing acid-gas contaminants from water, the method comprising the steps of: introducing a mixed production fluid comprising natural gas, water, and acid-gas components into a first separation apparatus;separating the mixed production fluid into at least a first distinct gas phase

1. A method for removing acid-gas contaminants from water, the method comprising the steps of: introducing a mixed production fluid comprising natural gas, water, and acid-gas components into a first separation apparatus;separating the mixed production fluid into at least a first distinct gas phase and a separate first distinct aqueous phase;collecting the first distinct aqueous phase and introducing an acid into the first distinct aqueous phase, the first distinct aqueous phase having a first concentration of acid-gases, a first concentration of associated conjugate bases, and a first pH, wherein the acid reduces the first pH of the first distinct aqueous phase to a second pH, the second pH being lower than the first pH;collecting the first distinct gas phase and treating the first distinct gas phase to remove acid-gas components therefrom, resulting in a second, substantially sweet gas phase that is substantially without acid-gas components;passing at least a portion of the second, substantially sweet gas phase through the first distinct aqueous phase at the second pH, resulting in a vapor phase composed of liberated acid-gas and stripping gas vapors, and a second distinct aqueous phase comprising a lower concentration of acid-gases and associated conjugate bases relative to the first distinct aqueous phase;separating and collecting the liberated acid-gas and stripping gas vapors;treating the liberated acid-gas and stripping gas vapors to remove acid-gas components, resulting in a clean stripping gas product;separating and collecting the second distinct aqueous phase; andtreating the second distinct aqueous phase with a second treatment step, resulting in a final aqueous product having a lower concentration of acid-gases and associated conjugate bases than the second distinct aqueous phase. 2. The method of claim 1, further comprising the step of raising the pH of the final aqueous product, using an alkaline material, for a particular end use. 3. The method of claim 2, wherein the particular end use is hydraulic fracturing. 4. The method of claim 1, wherein the final aqueous product has a combined concentration of a target acid-gas and associated conjugate base that is substantially zero. 5. The method of claim 1, wherein a target acid-gas and associated conjugate base species are removed substantially irreversibly. 6. The method of claim 1, wherein the step of passing at least a portion of the second, substantially sweet gas phase through the first distinct aqueous phase at the second pH is conducted at ambient conditions, without addition of heat to process fluids. 7. The method of claim 1, wherein the first distinct aqueous phase comprises hydrocarbons. 8. The method of claim 1, wherein the first distinct aqueous phase and second distinct aqueous phase comprise salt water. 9. The method of claim 1, wherein a concentration of total dissolved solids in the first distinct aqueous phase exceeds 100,000 parts per million by weight (ppmw). 10. The method of claim 1, wherein a concentration of hardness minerals in the first distinct aqueous phase exceeds 10,000 ppmw as CaCO3. 11. The method of claim 1, wherein the first distinct aqueous phase comprises produced water extracted from a subterranean formation. 12. The method of claim 1, wherein the second, substantially sweet gas phase is anoxic. 13. The method of claim 1, wherein the second, substantially sweet gas phase comprises natural gas. 14. The method of claim 1, wherein the second, substantially sweet gas phase is reused again as a stripping gas. 15. The method of claim 1, wherein a portion of the clean stripping gas product exits the process via a natural gas sales line. 16. The method of claim 1, further comprising the step of treating a portion of the clean stripping gas product to a further extent before the clean stripping gas product exits via a natural gas sales line. 17. The method of claim 1, wherein the second treatment step comprises introducing chlorine dioxide to the second distinct aqueous phase. 18. The method of claim 1, wherein a secondary treatment chemical is generated proximate a location of the second treatment step. 19. The method of claim 1, wherein the second treatment step comprises an introduction of chemicals selected to inhibit solids formation or deposition. 20. The method of claim 1, wherein the second treatment step comprises the introduction of chemicals selected to remove contaminants other than selected acid-gases from the first distinct aqueous phase. 21. The method of claim 1, wherein the method is performed in batches. 22. The method of claim 1, wherein the method is conducted in continuous feed. 23. A system for removing acid-gas contaminants from water, the system comprising: a first feed inlet fluidly coupled to a separator to supply to the separator a mixed production fluid comprising at least natural gas, water, and acid-gas components;a second feed inlet fluidly coupled to a first gas contactor vessel to supply a gas phase having natural gas and acid-gas components, the first gas contactor vessel in fluid communication with a vapor outlet of the separator, wherein in the first gas contactor vessel a mixture of acid-gas, natural gas, and stripping gas vapors is treated to remove acid-gas components;a third feed inlet fluidly coupled to a mixer to supply to the mixer an aqueous solution having acid-gases and associated conjugate bases and having an initial pH, the mixer in fluid communication with a liquid outlet of the separator;a fourth feed inlet fluidly coupled to the mixer to supply acid to the aqueous solution in the mixer;a fifth feed inlet fluidly coupled to a second gas contactor vessel, the second gas contactor vessel in fluid communication with an outlet of the mixer;a sixth feed inlet to the second gas contactor vessel, the second gas contactor vessel in fluid communication with a vapor outlet of the first gas contactor vessel to supply stripping gas to the aqueous solution in the second gas contactor vessel;a seventh feed inlet to the first gas contactor vessel, the first gas contactor vessel in fluid communication with a vapor outlet of the second gas contactor vessel;an eighth feed inlet to an acid-gas scavenging contactor vessel, the acid-gas scavenging contactor vessel in fluid communication with a liquid outlet of the second gas contactor vessel; anda ninth feed inlet to the acid-gas scavenging contactor vessel fluidly coupled to a supply of acid-gas scavenger chemical. 24. The system of claim 23, wherein the mixer, the second gas contactor vessel, and acid-gas scavenging contactor vessel are formed as a single contactor unit. 25. The system of claim 23, further comprising a tenth feed inlet to an alkaline contactor vessel to supply alkaline chemical to the aqueous solution conducted therein by an eleventh feed inlet in fluid communication with a liquid outlet of the acid-gas scavenging contactor vessel. 26. The system of claim 23, wherein the second gas contactor vessel comprises an internal sparge bar. 27. The system of claim 26, wherein the internal sparge bar is used to introduce stripping gas to the aqueous solution. 28. The system of claim 26, wherein the first gas contactor vessel is substantially horizontal. 29. The system of claim 26, further comprising a recycle loop to transfer fluid from one portion of the second gas contactor vessel to another portion thereof. 30. The system of claim 23, wherein substantially no waste gas stream is flared or emitted from the system.