METHOD OF PHTALIC ANHYDRIDE VAPOURS' CONTINUOUS DESUBLIMATION

The invention solves a method and an apparatus for the separation of solids from gaseous mixtures especially the separation of phthalic anhydride after its desublimation from mixtures with vapours of sublimable substances, steam, air or inert gases, which originate at sublimation refining or at catalytic production of phthalic anhydride by air oxidation of naphthalene or o-xylene. The flakes of phthalic anhydride, which originated after the decrease of temperature in the desublimator space were agglomerated and compacted due to the increase of velocity of gaseous mixture in contracted cross-section of the separator. The formed agglomerates are separated from the gaseous mixture and collected in a receiver well. From the well the agglomerates are transported by a conveyor or they are continuously melted. The melt formed outlets through a siphon. The rest 1 to 5% of phthalic anhydride is separated from gaseous mixture in a filter from wire net and by gradual melting is introduced into the receiver well.