Apparatus and method for ammonia removal from waste streams

A method for recovering ammonia from a fluid comprising:

• a. contacting said fluid with a sorbent comprising metal loaded media at condtions adapted to load ammonia onto said sorbent;
• b. separating said ammonia loaded sorbent from said fluid;
• c. separating said ammonia from said ammonia loaded sorbent by contacting said sorbent with a stripping solution comprising
• (1) a non-chelating weak acid, wherein said sorbent is regenerated and an ammonium-weak acid salt solution is formed in a spent stripping solution;
• or
• (2) sulfuric acid and zinc sulfate salt, wherein said sorbent is regenerated and an ammonium-zinc sulfate hydrate solution is formed in a spent stripping solution;
• d. separating said spent stripping solution from said regenerated sorbent;
• e. separating said ammonium-weak acid salt or said ammonium- strong acid salt from said spent stripping solution;
• and
• f. treating said ammonium salt solution to recover products therefrom

An apparatus for recovering ammonia from a fluid comprising:

• means for enclosing a metal loaded media able to reversibly sorb ammonia;
• inlet means, at an inlet portion of said means for enclosing, for admitting fluid or regenerant;
• outlet means, at an outlet portion of said means for enclosing, for exiting treated fluid or reacted regenerant;
• and
• regenerant source means comprising non-chelating weak acid, operatively connected to said inlet means.

A method for recovering ammonia from a fluid comprising:

• a. contacting said fluid with a sorbent comprising a metal ion loaded media, in a manner adapted to sorb ammonia on said sorbent;
• b. separating said ammoniated sorbent and said fluid;
• c. separating said ammonia from said ammoniated sorbent by contacting said ammoniated sorbent with a non-chelating weak acid to form a regenerant/ammonia salt;
• and
• d. separating said ammonia from said regenerant by one or more steps selected from the group comprising:
• (1) heating said ammonia/regenerant complex;
• (2) applying a vacuum to said ammonia/regenerant complex;
• and
• (3) contacting said ammonia/regenerant complex with a strong acid.

A method for treating an air stream containing ammonia comprising:

• contacting said air stream with a slurry comprising:
• particles of activated metal hydroxide, said particles dispersed in a liquid;
• or
• particles of metal loaded media, said particles dispersed in a liquid;
• and
• regenerating said particles and recovering said ammonia.

An apparatus for recovering ammonia from a fluid comprising:

• a. a container enclosing a metal loaded media, said metal loaded media able to reversibly sorb ammonia;
• b. an inlet in said container for admitting fluid or regenerant to said container;
• c. an outlet in said container for exiting treated fluid or reacted regenerant from said container;
• and
• d. a source of regenerant comprising non-chelating weak acid, operatively connected to an inlet at said container.

A method for removing ammonia from a fluid comprising:

• a. contacting said fluid with a sorbent of metal-loaded media in a manner adapted to load ammonia onto said sorbent;
• b. separating said fluid from said ammonia-loaded sorbent;
• c. contacting said separated ammonia loaded sorbent with a stripping solution of a strong acid and a metal salt, wherein an ammonium salt is formed with said metal salt in a spent stripping solution and said ammonia loaded sorbent is regenerated to a sorbent of metal loaded media;
• d. separating said spent stripping solution from said regenerated sorbent of metal loaded media;
• and
• e. treating said separated spent stripping solution in a manner adapted to crystallize an ammonium-metal salt therefrom

A method for removing ammonia from wastewater comprising:

• a. contacting an ammonia-laden wastewater stream with a zinc-loaded cation exchange resin to adsorb the ammonia;
• b. separating said zinc-loaded cation exchange resin containing said adsorbed ammonia and stripping the ammonia with a stripping solution of ZnSO4 and H2SO4 to form a spent regeneration solution of ammonium sulfate and zinc sulfate;
• and
• c. crystallizing zinc ammonium sulfate hydrate therefrom.

An apparatus for recovering ammonia from an ammonia-containing fluid comprising:

• a. a fluid-contacting device containing an ammonia sorbent of metal-loaded media;
• b. means for contacting said ammonia-containing fluid with said ammonia sorbent and sorbing said ammonia thereon to form an ammonia-depleted fluid;
• c. means for removing said ammonia-depleted fluid from the contacting device;
• d. means for contacting said ammonia-loaded sorbent with a stripping solution of a strong acid and a metal salt to form a spent regeneration solution of ammonium salt and metal salt;
• and
• e. means for treating said spent regeneration solution to crystallize an ammonium-metal double salt therefrom.

A method for treating an air stream-containing ammonia comprising:

• a. contacting said air stream directly with an aqueous stream of a stripping solution of a metal salt of a strong acid (zinc sulfate) and a strong acid (sulfuric acid) or with particles of metal-loaded media wherein said particles are thereafter treated by stripping ammonia from said particles by contact with a metal salt/strong acid (zinc sulfate/sulfuric acid) stripping solution;
• b. crystallizing an ammonium-metal salt hydrate (zinc sulfate hydrate) from either of said stripping solutions;
• and
• c. decomposing said crystallized ammonium-metal salt hydrate ammonium salt hydrate to release ammonia and regenerate said stripping solution.

A method for recovering ammonia from a fluid comprising:

• a. contacting said fluid with a sorbent comprising metal loaded media at conditions adapted to load ammonia onto said sorbent and produce an ammonia depleted fluid;
• b. separating said ammonia depleted fluid from said ammonia loaded sorbent;
• c. washing said ammonia loaded sorbent with an intermediate polarity solution to remove water therefrom;
• d. separating said ammonia from said ammonia loaded sorbent by contacting said ammonia loaded sorbent with a stripping solution of a regenerant comprising a substantially water insoluble non-chelating weak carboxylic acid, wherein regenerated sorbent and an ammonium regenerant salt solution is formed in a spent stripping solution;
• e. separating said spent stripping solution from said regenerated sorbent;
• and
• f. washing said regenerated sorbent with an intermediate polarity solvent to remove residual carboxylic acid therefrom before reuse thereof.