Process for nitrogen oxide waste conversion to fertilizer

A process for converting vapor streams containing at least one oxide of nitrogen to a liquid fertilizer composition comprising the steps of:

• a) directing a vapor stream containing the at least one oxide of nitrogen to a first contact zone,
• b) contacting said vapor stream with water to form oxy acid (s) of nitrogen from said at least one oxide of nitrogen,
• c) directing said acid(s) as a second stream to a second contact zone,
• d) exposing said second stream to hydrogen peroxide which is present within said second contact zone to convert at least some of any oxy acid (s) of nitrogen or ions other than in the nitrate form present within said second stream to nitrate ion,
• e) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone,
• f) adding hydrogen peroxide to said second contact zone when there is less than an excess of hydrogen peroxide in said second stream,
• g) adding a solution comprising potassium hydroxide to said second stream to maintain an acid pH in said second stream within said second contact zone to form a solution of potassium nitrate,
• h) adding additional potassium hydroxide to said second stream to adjust pH to between 5 and 11 within said second stream within said second contact zone to form additional potassium nitrate, and
• i) removing said solution of potassium nitrate from said second contact zone.

A process for converting vapor streams containing at least one oxide of nitrogen to a solution of nitrate comprising the steps of:

• a) directing a vapor stream containing the at least one oxide of nitrogen to a first contact zone,
• b) contacting said vapor stream with water to form oxy acid (s) of nitrogen from said at least one oxide of nitrogen,
• c) directing said acid(s) as a second stream to a second contact zone,
• d) exposing said second stream to hydrogen peroxide which is present within said second contact zone to convert at least some of any oxy acid (s) of nitrogen or ions other than in the nitrate form present within said second stream to nitrate ion,
• e) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone,
• f) adding hydrogen peroxide to said second contact zone when there is less than an excess of hydrogen peroxide in said second stream, and
• g) adding a solution comprising a hydroxide to said second stream to maintain an acid pH in said second stream within said second contact zone to form a solution of a nitrate.