IMPROVED EXHAUST VAPOUR DISPOSAL PROCESS DURING OVERHEATED STEAM DRYING

摘要

The partial current of exhaust vapours loaded with entrained valuable and/or inert substances is transferred as a steam-product current from drying plants operating with overheated steam as the drying gas, then is at least partially condensed by indirect heat exchange with a cooling medium. The exhaust vapour condensate is subsequently cleaned by at least one distillation step. By recirculating a partial current from the liquid phase of distillation plant (5), exhaust vapour condensate is used for absorbing the condensation energy of the gaseous current of exhaust vapours in an indirect heat exchanger (2). The exhaust vapour condensate thus produced is supplied to the distillation plant (5), where it is brought into a direct energy exchange with the recycled partial current of exhaust vapour condensate drawn from the liquid phase. A partial liquid stream having a higher concentration of entrained valuable and/or inert substances can thus be drawn from the liquid phase of the distillation plant (5). The vapour phase from the distillator (5) is further treated in an appropriate manner.