Manufacture of synthesis gas

Claim 1

IN THE MANUFACTURE OF SYNTHESIS GAS BY THE REACTION OF METHANE WITH STEAM TO FORM A SYNTHESIS GAS CONTAINING HYDROGEN AND CARBON MONOXIDE WITH THE HYDROGEN BEING IN MOLAR EXCESS OF THE CARBON MONOXIDE, THE IMPROVEMENT WHICH COMPRISES PASSING A REACTION MIXTURE COMPRISING METHANE AND STEAM DOWNWARDLY THROUGH A VERTICAL REACTION CHAMBER, PASSING DOWNWARDLY THROUGH SAID CHAMBER A MASS OF PREHEATED REFRACTORY PEBBLES AT AN INLET TEMPERATURE SUFFICIENT TO EFFECT THE DESIRED REACTION, FLOWING THE REACTION MIXTURE AND PEBBLES CONCURRENTLY THROUGH SAID MIXTURE ZONE WHEREBY THE TEMPERATURE IN THE DIRECTION OF FLOW DESCREASES DUE TO THE ENDOTHERMIC NATURE OF THE REACTION, INTRODUCING CATALYST FOR SAID REACTION INTO SAID REACTION ZONE FOR DOWNWARD FLOW THERETHROUGH, SAID CATALYST BEING INTRODUCED AT A PLURALITY OF POINTS SPACED ALONG THE LINE OF FLOW AND BEING ADMIXED WITH SAID PEBBLES AND REACTION MIXTURE IN SAID ZONE, SEPARATELY REGULATING THE QUANTITY AND ACTIVITY OF THE CATALYST INTRODUCED AT EACH OF SAID POINTS SO AS TO PROVIDE AN INCREASING CATALYST ACTIVITY IN THE DIRECTION OF FLOW, SAID INCREASING ACTIVITY TENDING TO COUNTERACT THE DEPRESSING EFFECT OF SAID DECREASING TEMPERATURE ON THE EXTENT OF REACTION IN THE LOWER PORTIONS OF SAID REACTION ZONE, RECOVERING SAID PEBBLES FROM THE BOTTOM OF SAID REACTION ZONE, REHEATING SAME, AND REINTRODUCING SAME INTO THE TOP OF SAID REACTION ZONE IN A CONTINUOUS CYCLE, SEPARATING SAID CATALYST FROM ADMIXTURE WITH SAID PEBBLES, SUBJECTING A PORTION OF SAID CATALYST TO REACTIVATION WHILE RETURING THE REMAINING PORTION TO THE REACTION ZONE WITHOUT REACTIVATION INTRODUCING SAID UNREACTIVATED CATALYST INTO SAID ZONE AT A PLURALITY OF THE AFORESAID POINTS INCLUDING THE FIRST AND EXCLUDING THE LAST OF SAID POINTS IN THE DIRECTION OF FLOW, THE UNREACTIVE CATALYST INTRODUCED TO SAID FIRST POINT BEING THE SOLE CATLAYST INTRODUCED THERETO AND A DIMINISHING QUANTITY OF UNREACTIVATED CATALYST BEING INTRODUCED AT EACH SUCCEEDING POINT IN THE DIRECTION OF FLOW, INTRODUCING SAID REACTIVATED PORTION OF SAID CATALYST INTO THE REACTION ZONE AT A PLURALITY OF POINTS EXCLUDING THE FIRST AND INCLUDING THE LAST OF SAID POINTS IN THE DIRECTION OF FLOW, THE REACTIVATED CATALYST INTRODUCED TO SAI D LAST POINT BEING THE SOLE CATALYST INTRODUCED THERETO AND AN INCREASING QUANTITY OF REACTIVATED CATALYST BEING INTRODUCED AT EACH SUCCEEDING POINT IN THE DIRECTION OF FLOW, AND SO PORTIONING THE RELATIVE AMOUNTS OF UNREACTIVATED AND REACTIVATED CATALYSTS INTRODUCED AT THE RESPECTIVE POINTS AS TO DIRECTION OF FLOW SUCH AS TO ESTABLISH A SUBSTANTIALLY CONSTANT EXTENT OF REACTION THROUGHOUT THE REACTION ZONE DESPITE SAID DECREASING TEMPERATURE, OTHERWISE DECREASING CATALYST ACTIVITY, AND DECREASING CONCENTRATION OF REACTANTS.