Valorization of airborne ammonia emissions of livestock farming by plasma-enabled conversion to ammonium nitrate fertilizer.

Ammonia emission by livestock farms in general and in the vicinity of Natura 2000 areas in particular is subject to increasingly stringent European and Flemish regulations. Meeting the eminent more stringent legislation will be technologically very challenging. Currently the best available technology for recovering the ammonia is by scrubbing the ventilated air with diluted sulphuric acid solution. Captured ammonia is converted to ammonium sulphate by reaction with sulphuric acid in the air washing device. Because of the limited solubility of ammonium sulphate, the obtained solution has little economic value as fertilizer, and large storage reservoirs are needed. We propose an innovative air scrubber concept with local production of nitric acid (HNO3) simply from oxygen, nitrogen and water molecules from air by a plasma reactor. In the scrubber ammonia reacts with nitric acid to ammonium nitrate, which is a superior fertilizer with larger economic value. The solubility of ammonium nitrate is much larger than for ammonium sulphate, which will minimize the volume of water and product to be handled. There will be no need for chemicals such as sulphuric acid. Reagents are locally produced simply from air by a plasma reactor. This original solution of an air pollution problem fits well with the notion of circularity since ammonia originating for the animal feed is converted to fertilizer for crop production.

Keywords:AMMONIA, PLASMA REACTOR, PLASMA TECHNOLOGY, FERTILIZER

Disciplines:Chemistry of plasmas, Air pollution and control, Sustainable development, Sustainable agriculture

Project type:Collaboration project