Light Cycle Oil (LCO) is a
diesel boiling range product from Fluid
Catalytic Cracking Units (FCCUs). However, LCO
is a poor diesel fuel blending component without
further processing. Oil refining is an
industrial process which involves separation,
conversion and finishing. FCC centered refinery
uses Fluid Catalytic Cracking Unit (FCCU) has
the major conversion unit. FCCU is responsible
for the production of petrol, LPG and Light
Cycle Oil (LCO).
Diesel is the most important fuel used in
automobiles because of its high efficiency. The
global demand for diesel is increasing than
petrol but many older refineries have optimized
their plant for producing more petrol than
diesel. Light Cycle Oil is the diesel boiling
range material, which is produced in addition to
gas and petrol in the FCCU. LCO is treated in
the diesel hydrotreater (DHT) unit to produce
low sulphur environment friendly diesel.
Production of LCO is increased in the FCCU by
employing medium conversion mode rather than
using traditional low conversion mode. Low
conversion mode will cause a loss of gas
production, deteriorate petrol octane rating and
also increase the production of low valued
slurry oil. With medium conversion technique
both gas quality and quantity is maintained and
improves the petrol octane rating. Medium
conversion mode also reduces the amount of low
valued slurry oil. Slurry oil contains LCO
boiling range material in it; hence a separate
slurry oil stripping tower is employed to
recover the LCO from slurry oil.