The present invention provides processes for removing nitrogen species from fresh water or high salinity water recirculated aquaculture systems. The processes are based on physico-chemical treatments which are performed at ambient temperatures and at low p H values thus keeping the total ammonia nitrogen concentrations below a value which is considered detrimental for the growth or survival rate of cultured fish/shrimp.

Processes for removing nitrogen species from fresh water or high salinity water recirculated aquaculture systems. The processes are based on physico-chemical treatments which are performed at ambient temperatures and at low pH values thus keeping the total ammonia nitrogen concentrations below a value which is considered detrimental for the growth or survival rate of cultured fish/shrimp.

A method for producing an ion exchange resin. The method comprises steps of: (a) providing a basic ion exchange resin in the acidic form which comprises amino polyol groups and has a volume % swell from 15 to 30% upon conversion from the basic form to the acidic form, and (b) washing the resin with water or aqueous acid.

A method for producing an ion exchange resin. The method comprises steps of: (a) providing a basic ion exchange resin in the acidic form which comprises amino polyol groups and has a volume % swell from 15 to 30% upon conversion from the basic form to the acidic form, and (b) washing the resin with water or aqueous acid.

A method of destroying a fluorocarbon compound includes regenerating an adsorbent to remove the fluorocarbon compound and to produce a regeneration fluid having a concentration of the fluorocarbon compound and directing the regeneration fluid to an electro-oxidation system. The method also includes applying a current to the electro-oxidation system to oxidize the fluorocarbon compound within the regeneration fluid and measuring a quantity of fluorides in the regeneration fluid to determine the progress of the removal of the fluorocarbon compound from the regeneration fluid.

Processes and apparatuses for degrading PFAS into calcium fluoride, carbon dioxide, and water. PFAS are heated and introduced to a calcium base which will degrade the PFAS. The PFAS may be in a stream that is a PFAS enriched stream formed by desorbing the PFAS from an adsorbent which removed the PFAS from a contaminant stream. The PFAS may be desorbed in the presence of the calcium base. The calcium base may be calcium hydroxide, calcium oxide, calcium carbonate, or combinations thereof.

Processes and apparatuses for degrading PFAS into calcium fluoride, carbon dioxide, and water. PFAS are heated and introduced to a calcium base which will degrade the PFAS. The PFAS may be in a stream that is a PFAS enriched stream formed by desorbing the PFAS from an adsorbent which removed the PFAS from a contaminant stream. The PFAS may be desorbed in the presence of the calcium base. The calcium base may be calcium hydroxide, calcium oxide, calcium carbonate, or combinations thereof.

The present invention is directed at a novel ion exchange regeneration process where there is no need for resin separation or acid and base consumption for regeneration. An exhausted strong acid/strong base mixed bed resin suitable for seawater desalination can be regenerated in situ, that is without the need for bead separation, by washing with high pressure (<10 atm) concentrated ammonium bicarbonate (AB) solution (up to a concentration of 8-10 m) at moderately elevated temperatures, of up to 60-80 C. Under these conditions a relatively small amount of AB solution can be used to regenerate an exhausted mixed bed resin, converting it into a form where it is saturated with absorbed NH.sub.4.sup.+ and HCO.sub.3.sup. ions. This resin can then be used for seawater desalination, via direct exchange with Na.sup.+ and Cl.sup. ions, as well as other ions in seawater. By this method the volume of produced drinking water can be at least 2-4 times the volume of the AB solution required, which is then discarded as waste concentrated salt solution. The AB dissolved in the desalinated product water can be easily thermally decomposed, by heating to 60-80 C., or lower under a reduced pressure, which completely removes the AB in the form of the emitted gases NH.sub.3 and CO.sub.2, which can then be captured and redissolved in cool water to reform the regenerant solution. The application of an increased pressure for driving super saturated ammonium bicarbonate regeneration can also be carried out using guided ultrasonic waves. A suitable frequency and intensity of wave-guided ultrasonic waves, transmitted along the inside of a container housing the exhausted mixed bed resin, immersed in concentrated or supersaturated AB solution, drives the ion exchange regeneration process. Alternatively, the pressure applied to the resin could be generated via the centrifugal forces produced inside a spinning drum.

The present invention is directed at a novel ion exchange regeneration process where there is no need for resin separation or acid and base consumption for regeneration. An exhausted strong acid/strong base mixed bed resin suitable for seawater desalination can be regenerated in situ, that is without the need for bead separation, by washing with high pressure (<10 atm) concentrated ammonium bicarbonate (AB) solution (up to a concentration of 8-10 m) at moderately elevated temperatures, of up to 60-80 C. Under these conditions a relatively small amount of AB solution can be used to regenerate an exhausted mixed bed resin, converting it into a form where it is saturated with absorbed NH.sub.4.sup.+ and HCO.sub.3.sup. ions. This resin can then be used for seawater desalination, via direct exchange with Na.sup.+ and Cl.sup. ions, as well as other ions in seawater. By this method the volume of produced drinking water can be at least 2-4 times the volume of the AB solution required, which is then discarded as waste concentrated salt solution. The AB dissolved in the desalinated product water can be easily thermally decomposed, by heating to 60-80 C., or lower under a reduced pressure, which completely removes the AB in the form of the emitted gases NH.sub.3 and CO.sub.2, which can then be captured and redissolved in cool water to reform the regenerant solution. The application of an increased pressure for driving super saturated ammonium bicarbonate regeneration can also be carried out using guided ultrasonic waves. A suitable frequency and intensity of wave-guided ultrasonic waves, transmitted along the inside of a container housing the exhausted mixed bed resin, immersed in concentrated or supersaturated AB solution, drives the ion exchange regeneration process. Alternatively, the pressure applied to the resin could be generated via the centrifugal forces produced inside a spinning drum.