Improved Process for Scrubbing and Treating NOₓ Liquor

A new process and equipment have been developed for reducing the emissions of hazardous nitrogen oxides (NOx), and eliminating a hazardous waste stream. In this process, a waste gas stream of nitrogen and NOx, arising from spacecraft-propellant operations, is reacted (scrubbed) with a dilute solution of hydrogen peroxide (scrubber liquor). The resulting liquor is treated simultaneously with potassium hydroxide during the scrubbing operation to produce potassium nitrate. The overall effect of the process is to absorb NOx from the waste gas stream into the scrubber liquor where NOx is converted into an aqueous solution of potassium nitrate, which can be used as a fertilizer.