Processes for producing petrochemical products that utilize fluid catalytic cracking of a lesser boiling point fraction with steam

A process for operating a hydrocarbon feed conversion system for producing a petrochemical product stream from a hydrocarbon feed stream, the process comprising:

• introducing the hydrocarbon feed stream to a feed separator;
• separating the hydrocarbon feed stream into at least a lesser boiling point fraction stream and a greater boiling point fraction stream in the feed separator;
• combining steam with the lesser boiling point fraction stream upstream of the cracking of the lesser boiling point fraction stream such that the steam:oil mass ratio is from 0.2 to 0.8 such that the partial pressure of the contents of the lesser boiling point fraction stream is reduced;
• passing the greater boiling point fraction stream to a first fluid catalytic cracking unit;
• passing the lesser boiling point fraction stream to a second fluid catalytic cracking unit;
• cracking at least a portion of the greater boiling point fraction stream in the first fluid catalytic cracking unit in the presence of a first catalyst at a reaction temperature of from 500° C. to 700° C. in an environment comprising less than 0.1 mol. % water to produce a first cracking reaction product stream;
• cracking at least a portion of the lesser boiling point fraction stream in the second fluid catalytic cracking unit in the presence of a second catalyst and at a reaction temperature of from 500° C. to 700° C. to produce a second cracking reaction product stream;
• and
• separating the petrochemical product stream from one or both of the first cracking reaction product stream or the second cracking reaction product stream,
• wherein each of the first fluid catalytic cracking unit and the second fluid catalytic cracking unit is a downflow fluid catalytic cracking unit.