System for conducting conversions in the presence of a contact mass

Claim 1

IN A PROCESS FOR CONTINUOUSLY CATALYTICALLY COVERTING FLUID HYDROCARBONS IN THE PRESENCE OF PARTICLE-FORM SOLID CATALYST WHEREIN THE CATALYST IS MOVED DOWNWARDLY THROUGH A CONVERSION ZONE OPERATING UNDER PRESSURE AS A SUBSTANTIALLY COMPACT COLUMN OF PARTICLES AND THE FLUID HYDROCARBONS ARE PASSED UNDER CONVERSION CONDITIONS INTO CONTACT WITH SAID CATALYST IN SAID CONVERSION ZONE AND WHEREIN ACTIVE CATALYST PARTICLES ARE INTRODUCED TO SAID ZONE NEAR THE TOP THEREOF IN ORDER TO MAINTAIN SAID COLUMN OF CATALYST IN SAID CONVERSION ZONE THE IMPROVEMENT WHICH COMPRISES: INTRODUCTING THE ACTIVE CATALYST PARTICLES INTO SAID CONVERSION ZONE FROM A SUBSTANTIALLY COMPACT STREAM OF CATALYST PARTICLES MAINTAINED ABOVE SAID CONVERSION ZONE WHICH STREAM FORMS A CONTINUOUS BODY OF CATALYST WITH SAID COLUMN AND WHICH IS OF SUCH CROSS-SECTIONAL AREA AND VERTICAL LENGTH ABOVE SAID ZONE AS TO INSURE GRAVITY FLOW OF CATALYST AT THE REQUIRED RATE INTO SAID CONVERSION ZONE AGAINST THE GASEOUS PRESSURE THEREIN, SAID COMPACT STREAM BEING FURTHER OF SUCH CROSS-SECTIONAL AREA AND LENGTH THAT THE QUOTIENT OF THE TWO-THIRDS POWER OF THE STREAM LENGTH IN FEET DIVIDED BY THE CROSS-SECTIONAL AREA OF SAID STREAM IN SQUARE FEET IS LESS THAN