IMPROVED HYDROCARBON CATALYTIC CRACKING PROCESS

摘要

HYDROCARBON FLUID CATALYTIC CRACKING (FCC) PLANTS ARE DEBOTTLENECKED BY REPLACING AIR FEED TO THE CRACKING CATALYST REGENERATOR WITH OXYGEN AND CARBON DIOXIDE EXHAUST FROM THE CATALYST REGENERATOR AND REMOVING METHANE AND HYDROGEN FROM THE WET GAS STREAM LEAVING THE MAIN FRACTIONATOR OVERHEAD RECEIVER PRIOR TO ITS INTRODUCTION INTO A WET GAS COMPRESSOR SYSTEM. NITROGEN IS REMOVED FROM THE EXHAUST GAS AND METHANE AND HYDROGEN ARE REMOVED FROM THE WET GAS IN THE SAME PRESSURE SWING ADSORPTION (PSA) PLANT. DURING AIR REPLACEMENT, EXHAUST GAS IS PROCESSED IN THE PSA PLANT AND WHEN THE DESIRED AMOUNT OF NITROGEN IS REMOVED FROM THE EXHAUST GAS, FEED OF EXHAUST GAS TO THE PSA PLANT IS TERMINATED AND FLOW OF WET GAS TO THE PSA PLANT IS INITIATED.