Page 140 - Fluid Catalytic Cracking Handbook

FCC Catalysts 115

Catalyst management is a very important aspect of the FCC process.
Selection and management of the catalyst, as well as how the unit is
operated, are largely responsible for achieving the desired product.
Proper choice of a catalyst will go a long way toward achieving a
successful cat cracker operation. Catalyst change-out is a relatively
simple process and allows a refiner to select the catalyst that maximizes
the profit margin. Although catalyst change-out is physically simple,
it requires a lot of homework as discussed later in this section.
As many catalyst formulations are available, catalyst evaluation
should be an ongoing process. However, it is not an easy task to
evaluate the performance of an FCC catalyst in a commercial unit
because of continual changes in feedstocks and operating conditions,
in addition to inaccuracies in measurements. Because of these limita-
tions, refiners sometimes switch catalyst without identifying
the objectives and limitations of their cat crackers. To ensure that a
proper catalyst is selected, each refiner should establish a methodology
that allows identification of "real" objectives and constraints and
ensures that the choice of the catalyst is based on well-thought-
out technical and business merits. In today's market, there are over
120 different formulations of FCC catalysts. Refiners should evalu-
ate catalyst mainly to maximize profit opportunity and to minimize
risk. The "right" catalyst for one refiner may not necessarily be "right"
for another,
A comprehensive catalyst selection methodology will have the
following elements:

1. Optimize unit operation with current catalyst and vendor
a. Conduct test run
b. Incorporate the test run results into an FCC kinetic model
c. Identify opportunities for operational improvements
d. Identify unit's constraints
e. Optimize incumbent catalyst with vendor
2. Issue technical inquiry to catalyst vendors
a. Provide test run results
b. Provide E-cat sample
c. Provide processing objectives
d. Provide unit limitations