Process and a system for enhancing the yield of light olefins

An integrated circulating fluidized bed process for simultaneous dehydration of ethanol and cracking of a hydrocarbon feedstock, wherein the process comprises:

• feeding the hydrocarbon feedstock (1) having a conradson carbon content (CCR) of at least 4 wt % and a regenerated catalyst (2) obtained from a coke combustor (a) to a fluidized bed cracking reactor (b);
• cracking the hydrocarbon feedstock at a temperature in a range of 490 to 680° C. while depositing coke on the catalyst to obtain a reaction mixture comprising hydrocarbon vapor products and a coke-laden catalyst;
• separating the hydrocarbon vapor products and the coke-laden catalyst at the end of the fluidized bed cracking reactor (b), and routing the hydrocarbon vapor products for fractionation (3);
• stripping the coke-laden catalyst to remove unseparated hydrocarbon vapor products contained therein;
• routing the coke-laden catalyst obtained from the stripping step (4) and ethanol (5) to a dehydration reactor (c) for dehydrating ethanol to ethylene and to obtain a product mixture and a deactivated catalyst, wherein the dehydration reactor (c) is maintained at a temperature in a range of 300 to 600° C., wherein the product mixture (6) is routed to the fluidized bed cracking reactor (b) for fractionation;
• routing the deactivated catalyst (7) obtained from the dehydrating step to the coke combustor (a) and burning the coke on the deactivated catalyst in the presence of air or oxygen containing gases (8) at a temperature in a range of 600-700° C. to obtain the regenerated catalyst and flue gas (9);
• and
• circulating the regenerated catalyst (2) to the fluidized bed cracking reactor (b) for cracking the hydrocarbon feedstock (1),
• wherein the process simultaneously increases the cracking of the hydrocarbon feedstock and dehydration of ethanol.