Process for the production under pressure of dry gaseous hydrogen chloride from concentrated aqueous hydrochloric acid

Claim 1

IN THE PROCESS FOR OBTAINING DRY, GASEOUS HYDROGEN CHLORIDE FROM STRONG AQUEOUS HYDROCHLORIC ACID BY DISTILLATION FROM A COLUMNN OF LIMITED CROSS-SECTIONAL AREA, THE IMPROVEMENT BY WHICH THE STRONG ACID IS HEATED TO A TEMPERATURE OF BETWEEN ABOUT 115*C. AND 120*C. TO FORM A MIXTURE OF HYDROGEN CHLORIDE GAS AND AQUEOUS AZEOTROPIC HYDROCHLORIC ACID, INJECTING SAID MIXTURE, WHILE AT SAID TEMPERATURE AND AT A PRESSURE OF FROM ABOUT 1 TO 2 GAUGE ATMOSPHERES, TANGENTIALLY INTO AN UNFILLED SEPARATION ZONE IN AN INTERMEDIATE PORTION OF A FILLED SEOARACOLUMN WHERE THE TURBULENCE EFFECTED BY THE TANGENTIAL INJECTION OF SAID MIXTURE CAUSES A SEPARATION OF THE HYDROGEN CHLORIDE GAS FROM THE AQUEOUS ACID, SAID GAS BEING DIRECTED UPWARDLY FROM THE SEPARATION ZONE TO A DISCHARGE ZONE AND SAID AQUEOUS ACID BEING DIRECTED DOWNWARDLY INTO A HEATING ZONE, SUPPLYING HEAT TO SAID HEATING ZONE TO EVOLVE A FURTHER PORTION OF HYDROGEN CHLORIDE GAS FROM THE AQUEOUS ACID IN SAID HEATING ZONE, DISRECTING THE RESULTING HYDROGEN CHLORIDE GAS MIXTURE AT THE ABOVE PRESSURE FROM THE DISCHARGE ZONE INTO A CONDENSING ZONE WERE THE RESIDUAL MOISTURE CONTENT THEREOF IS SUBSTANTIALLY SEPARATED THEREFROM AS A SMALL AMOUNT OF A STRONG AQUEOUS HYDROCHLORIC ACID SOLUTION, COLLECTING THE SUBSTANTIALLY DRY HYDROGEN CHLORIDE GAS LEFT BY THE CONDENSING ACID IN A COLLECTION ZONE, DIRECTING THE CONDENSED ACID DOWNWARDLY THROUGH THE UPWARDLY PATH OF THE HYDROGEN CHLORIDE GAS MIXTURE DISTILLING IN THE COLUMN TO STRIP AN ADDITIONAL AMOUNT OF HYDROGEN CHLORIDE GAS THEREFROM AND REMOVING THE AZEOTROPIC ACID FROM THE HEATING ZONE SO AS TO KEEP THE LIQUID LEVEL IN THE COLUMN BELOW THE SEPARATION ZONE.