The typical fuels refinery has as a goal the
conversion of as much of the barrel of crude oil into transportation fuels as is
economically practical. Although refineries produce many profitable products,
the high-volume profitable products are the transportation fuels gasoline,
diesel and turbine fuels, and the light heating oils. No. 1 and No. 2. These
transportation fuels have boiling points between 0 and 345c. Light heating oils
are not properly transportation fuels but the hydrocarbon components are
interchangeable with those of diesel and jet fuels, only the additives are
different. Although products such as lubricating oils, refrigeration and
transformer oils, and petrochemical feedstock’s are profitable, they amount to
less than 5 percent of the total crude oil charged to U.S. refineries.
The process flow and products for a complete
refinery of high complexity are shown in Figure 1.1. The processing equipment
indicated is for processing crude oils of average gravities and sulfur contents.
Crude oils with low API gravities and high sulfur contents require additional
hydro treating equipment.
The quality of crude oils processed by U.S.
refineries is expected to worsen slowly in the future with the sulfur contents
and densities to increase. The greater densities will mean more of the crude oil
will boil above 566C. Historically this high-boiling material or residua has
been used as heavy fuel oil but the demand for these heavy fuel oils has been
refineries to process the entire barrel of crude rather than just the material
boiling below 1050F. Sulfur restrictions on fuels will affect bottom-of-barrel
processing as well. These factors will require extensive refinery additions and
modernization and the shift in market requirements among gasoline’s and
reformulated fuels for transportation will challenge catalyst suppliers and
refinery engineers to develop innovative solutions to these problems.