Hydrocarbon Processing - February 2022 - 24

Digital Technologies
TABLE 1. Benefi ts of MB reactor
Customer interests
High-accuracy model of selected
properties; integration of petrochemical
Deep understanding and optimization
of refi ning chemistries
Catalyst design and development
Resid processing
Apply user's in-house kinetics
and reactor models
Propagation of detailed high-quality data of
reactors to proprietary planning softwarec
An optimal way to provide high-quality
data to machine-learning model
Required specs
Identify branched isomers
of PIONA
Describe more realistic kinetic
and mechanism
Intrinsic kinetic parameters
Conventional reactor MB reactor
Only supports
empirical correlation
Not supported
Not supported
Describe heavy-end conversion Not well-supported
Allow users to add or edit
components, reactions, kinetics
Estimate molecule-based
structural properties
Process data (measurable
and non-measurable) of all
necessary dimensions
Not supported
Not supported
Not well-supported
Includes detailed branched molecular
species
Detailed reaction path:
isomerization, HDS
Obtains more intrinsic kinetic
parameters of catalyst; less dependent
on fl owsheet, feedstocks
Includes archipelago resid structure
and reactions
Automates code generation for user's
in-house components, reactions, kinetics
Supports estimations of molecule-based
structural properties
Inherently provides densifi ed data and
reveals most important data among
complex chemistries
fining or petrochemical reactor. Employing a linear-free energy
relationship (LFER)3,4,5
technique, refiners can simulate and
calibrate a complex refining reactor model with only O (30)
kinetic parameters and obtain the high-fidelity and high-granularity
molecular data of the products. The benefits of the MB
reactor are summarized in TABLE 1.
An MB model builder was developed for users to include
FIG. 2. Customized MB reformer model in MB reactor.
their own detailed molecular models into the MB reactor without
requiring hard coding. The MB model builder has been used
to develop a MB hydrocracker/hydrotreater model in terms of
more than 2,400 molecules and 5,700 reactions.6
Refiners can
use this unit operation to simulate and calibrate a hydrocracker
model and propagate high-fidelity molecular data through a
flowsheet of a refinery.
SINOPEC Research Institute of Petroleum Processing
(RIPP) leveraged its own molecular reformer models to the MB
reactor via an MB builder and successfully simulated a four-bed
industrial CCR plant, as shown in FIG. 2.
In addition to modeling petroleum feedstocks at the molecuFIG.
3. Molecular sustainable HPR across a wide range of refining and
chemical models.
sisting of 22 distinct molecular compound classes and more
than 60,000 molecules with a comprehensive rigorous thermodynamic
property package driven by proprietary physical
properties modelsa
. By leveraging the information from that
library and the analytical data of crude oils, MC can characterize
the molecular compositions of crude assays so that they
optimally match molecular and bulk measurements.
Using the molecular assays from MC as the initial values, a
general molecule-based (MB) reactor1,2
was developed to simulate and optimize molecular reactor
models and propagate the molecular information throughout
the flowsheet. The MB reactor can organize O (10,000) molecular
components in refining streams as a set of homologous
series and describe O (10,000) distinct reactions in a given re24
FEBRUARY 2022 | HydrocarbonProcessing.com
lar level, the MB reactor can also model alternative hydrocarbon
feedstocks such as biomass, lignin, cellulose, hemicellulose,
plastics, coal, etc., allowing the MB reactor to support modeling
sustainable feedstocks in a refinery flowsheet. A green diesel7
model to upgrade biofuels was developed via an MB reactor.
Takeaways. Molecular modeling can address the upcoming
challenges for refiners, and it is possible to track the molecular
compositions of any stream in a flowsheet across a wide range of
refining and chemical models, as shown in FIG. 3. Users can utilize
high-fidelity molecular data, not only for a sustainable crude-tochemicals
steady-state simulation or calibration, but also for the
integration with online optimization or for planning and scheduling.8,9
Molecular
modeling provides an optimal plant digital twin
modeling framework
solution to optimize refining operations for decades to come.
NOTES
a AspenTech PC SAFT models
b Aspen HYSYS Petroleum Refining V12.0
c Aspen PIMS
LITERATURE CITED
Complete literature cited available online at www.HydrocarbonProcessing.com.
http://www.HydrocarbonProcessing.com http://www.HydrocarbonProcessing.com
Hydrocarbon Processing - February 2022

Table of Contents for the Digital Edition of Hydrocarbon Processing - February 2022
