Process intensification using energy-free highly enriched air: Application to seawater desalination plants

A new process layout to intensify and make more sustainable chemical processes that use open-loop cooling/heating systems is broached. This new process demonstrates the possibility to recover a stream of highly enriched air without any additional operational cost, but simply exploiting differently the existing energy sources. Enriched air can therefore be used to reduce the variable costs of the intensified plants as well as to reduce the volume of process facilities dedicated to steam generation or to directly increase the net operating margin as additional product (industrial or medical gas). General and dedicated process simulations combined with experimental evidence demonstrate the feasibility and the effectiveness of the proposed intensification. The application to the multi-effect distillation technology for seawater desalination is described.