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To improve the efficiency of aerosol separation, a process sequence for particle enlargement by condensation of water vapor on their surface is suggested. The presented method makes use of packed columns in non‐equilibrium operation to achieve supersaturation, which is required for droplet growth. Although this method is known for several years, it is not widely used in industrial processes and still needs accurate investigations for consolidation and establishment. The simulation tool AerCoDe3.0 for predicting saturation and particle growth in packed columns allows investigating the thermal energy consumption under various operation conditions. Based on the results obtained in this study, optimized arrangements of columns, which are applicable as preconditioning step for existing particle separators, are proposed. [ABSTRACT FROM AUTHOR]

A new method for the production of organic nanoparticles or nanosuspensions in a liquid ring vacuum pump is presented. A hot carrier gas charged under vacuum conditions with poorly water-soluble organic substances is compressed and simultaneously cooled by the partially evaporating sealant water of the liquid ring vacuum pump. During compression and quenching, the gas-vapor mixture becomes highly supersaturated and aerosol formation initiated by homogeneous nucleation occurs in the compression chambers between the impeller blades of the pump. The thus generated gas-borne droplets or solid particles are mainly trapped and enriched in the sealant ring liquid, which is discharged, separated from the carrier gas in an external separator and returned to the pump. Experiments yielded aqueous nanosuspensions of insoluble organic substances with typical particle sizes between 50 and 300 nm, as well as foam in the external gas-liquid separator. The foam showed stable structures due to incorporated solid nanoparticles. [ABSTRACT FROM AUTHOR]