Process Systems Enterprise Limited
email this page print this page
pdf overview

MBE for Chemicals: partial oxidation reactions

Enhancing throughput and reducing catalyst costs

Hydrocarbon Processing
Optimize terephthaldehye reactor operations [Hydrocarbon Processing; LG Chem, Ltd]

 

 

We were able to reduce time between R&D experiments and plant design significantly

— Frederic Bazer-Bashi,
Arkema [PSE AM 2008]

 

 

Typical applications deal with catalytic fixed-bed tubular, annular and multitubular reactors for manufacture of:

Acrylic acid (AA)
Dimethyl sulphide
Fischer-Tropsch gas-to-liquids (GTL)
Maleic anhydride
Methanol from syngas (e.g. Lurgi)
p-diiodobenzene
Phthalic anhydride (PA)
Propylene oxide (PO)
Terephthaldehyde

 

 

 

 

Partial oxidation reactions – used in the manufacture of many basic chemical building blocks such as acrylic acid, propylene oxide and pthalic anhydride – are a fundamental operation within the chemical industry.

However the design and operation of such processes is challenging. The key design and operational issues – selectivity, catalyst pellet design, reactor geometry and cooling – are closely interrelated.

Fortunately partial oxidation processes lend themselves well to Model-Based Engineering techniques, and there is a strong body of success in optimising reactor design and operation.

Model-Based Engineering of partial oxidation processes

PSE has extensive experience in this area. We can model, provide models for, or help you to model a wide variety of reactors and reaction types.

This is embodied in high-fidelity process models such as PSE's Advanced Model Library for Fixed-Bed Catalytic Reaction (AML:FBCR) and advanced industry-proven methodologies for detailed modelling and optimisation of design and operation.

PSE's Model-based Engineering approach is typically used to address the following aspects of operation and design of full-scale commercial operations:

Enhanced selectivity. Improved internals design or operating conditions can enhance selectivity to the main reaction.
Improved cooling design. By improving cooling fluid flows radial temperature profiles can be made more uniform, resulting in a more uniform product.
Reduction in hot-spot formation. With improved internals design or catalyst loading it is possible to reduce the likelihood of or eliminate hotspots.
Extension of catalyst life. Reducing the likelihood of hotspots and improving temperature distribution can help extend the catalyst life significantly.
Optimal catalyst loading. Tubes can be loaded with optimal catalyst profiles to ensure uniform temperature distribution and reduction in hotspot formation.
Optimisation of operating conditions. Operating conditions can be regularly optimised using the model to maximise catalyst life while meeting production targets.
Accurate reaction characterisation. Model-Based Engineering techniques allow the accurate characterisation of reaction sets from only limited experimental data.
Detailed equipment design. PSE's hybrid modelling technology provides the quantitative accuracy to perform detailed reactor design with confidence.
Activity monitoring. Model-based techniques can be used to determine up-to-date catalyst activity based on oeprating data history.
Optimal catalyst design. Model-based Innovation techniques are used to optimise the design of catalyst pellets based on operating performance.

Payback on such projects is typically of the order of 6 to 12 months, depending on whether there is capital expenditure or not.