Continuous process of recovering pure, concentrated ammonia

Abstract From the Canadian patent

This invention relates to a continuous process of recovering pure, concentrated ammonia from waste water or from aqueous, liquors, which in addition to ammonia contain acid constituents which process comprises a stripping off of gas water de-acidifi-, cation and scrubbing. In this process ammonia is stripped from, the aqueous mixture and then scrubbed with an aqueous solution pure, ammonia being withdrawn and subjected to fine purification. The residual ammonia is stripped from the spent scrubbing liquor previously obtained then withdrawn and recycled. Further aqueous, solution having a (CO2+H2S):NH3 ratio ? 1 are de-acidified by stripping acid constituents.