PROCESS AND APPARATUS FOR CONCENTRATING A DILUTE SOLUTION OF CORROSIVE PRODUCTS

摘要

1445354 Distilling corrosive liquids SOC NATIONALE DES POUDRES ET EXPLOSIFS ANTAR PETROLES DE L ATLANTIQUE and ANTARGAZ 19 Dec 1973 [19 Dec 1972] 58874/73 Heading B1B A dilute solution of H 2 SO 4 is introduced at 6 and flows downward over the silica granules 7 in countercurrent to hot combustion gas from orifices 22 and 25. The acid entering the tunnel 27 is thus preconcentrated while the gases carrying volatile components from the dilute liquid pass to washing section 5 where the gases are washed with cold water and the product is fed outside for re-use. The preconcentrated sulphuric acid flows down the cascades in tunnel 27 and is heated and concentrated by radiant heat from burners 34. The individual cascade trays 29 can be heated to different temperatures by varying combustible mixture to the burners and to leave the last tray at the boiling point of sulphuric acid. A sheet of heat-resistant gas-impermeable transparent silica is placed between the cascades and the burners (Fig. 2 not shown) to protect the burners against leaks of gas and acid.