Hot Microbubble Injection in Thin Liquid Film Layers for Ammonia-Water Separation

140 MT of NH$_{3}$ produced p.a. barely keeps up with the global usage of this ubiquitously used commodity. NH$_{3}$ manufacture {\&} later remediation from landfill leachate to lower eco-toxicity makes further~demands on the energy utilised for this ``NH$_{3}$ cycle.'' Moreover, current methods for lowering eco-toxicity destroy NH$_{3}$ rather than recovering it. Air stripping is a widely employed low energy industrial process used for NH$_{3}$ recovery but has a long processing time-$\cong $24h for 60{\%} efficiency {\&} 100h for 95{\%} efficiency. The solution presented herein is based on hot microbubble injection in thin liquid film layers designed to separate NH$_{3}$ from NH$_{3}$-H$_{2}$O solutions. The transport phenomena exhibited by the microbubbles helps them separate volatile liquids effectively with negligible sensible heat transfer. This process is nearly isothermal simply because evaporation by microbubbles is controlled by internal mixing, which is fast relative to sensible heat transfer, when limited to short contact times in thin films. A 1000-3000-fold increase in mass transfer, over conventional stripping, and a 100{\%} separation efficiency achieved in a processing time of 30 minutes is observed, potentially, if persisting with industrial scale up, resulting in a 200-fold reduction in processing time.