Process Systems Enterprise Limited
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gPROMS for simulation and modeling of reactors

Benefits of simulation and modeling

"Modelling gave us 'perfect insight' into our multitubular reactor and enabled us to come up with a high-performance design "

Dr Sang Phil Han, LG Chem, Ltd

       Optimized multitubular reactor shell temperature profiles

A typical benefit: optimised radial temperature distribution in a multitubular reactor, leading to longer catalyst life

Publications
Hydrocarbon Processing: Optimize terephthaldehyde reactor operations
Hydrocarbon Processing: Enhanced methods optimize catalyst ownership costs

 

 

 

 

 

Which catalyst?

Which catalyst?

Which catalyst?

What internal configuration?

What internal configuration?

What changeover frequency?

 

 

 

 

 

Troubleshooting

Troubleshooting: "What is happening inside there?"

 

Modelling answers questions such as:

"Will catalyst A or catalyst B give me a better lifecycle return?"

"How do I optimise catalyst loading for a fixed-bed reactor?"

"What is the optimal startup procedure for this unit?"

"What is the optimal grade-change policy when moving from product quality A to B?"

"What is the optimal cooling medium inlet temperature?"

 

 

 

 

 

 

 

 

 

 

ModelCare logo

PSE's ModelCare service is designed to deliver high-quality modelling projects AND transfer know-how to your modelling specialists.

 

 

The difference in profitability (or cost) between a well-designed and badly-designed reactor can run to tens of millions of dollars over its lifetime.

A well-designed reactor:

The overall benefits can be summarised as: higher revenues, lower capital and operating costs, better environmental compliance and increased customer satisfaction.

Modelling can help achieve all of these

Advanced Process Modelling provides detailed, high-accuracy predictive information for quantitative decision support at all stages of the design and operation of reaction processes.

This means that virtually every design decision – from the choice of catalyst to the exact placement of baffles in a multitubular reactor shell, to the temperature and pressure at which a reactor is operated on a particular day – can be determined based on a precise analysis of the outcome.

Similar considerations apply to operating plant, where models can be deployed offline or online to generate value daily.

The 15 specific benefits of reactor modeling

There are many commercial and technical benefits of applying modelling, in both design and operation. The financial value depends on the type of product, and scale of operation.

The top 15 benefits are:

  1. Higher throughput. By optimizing the design and operation of reactors, it is possible in many cases to achieve significantly enhanced throughput.
    2. Benefit: greater revenue from higher production; better ROI for capital invested; higher customer satisfaction.
  2. Better product quality. By optimizing design and operation, it is possible to achieve better and more consistent product quality.
    3. Benefit: higher prices for products; easier downstream processing (see below) leading to reduced costs and increased uptime; consistency leading to higher customer satisfaction.
  3. Extended catalyst life. "Designing-out" of hot-spots in catalytic reactors means that (a) the catalyst lasts longer or (b) if desired, the reactor can be run at a higher overall temperature, aiding conversion and selectivity.
    Benefit: reduced downtime, lower catalyst lifetime costs, higher throughput and better overall quality product, resulting in a more profitable operation.
  4. Improved downstream processing. By improving reactor product quality and consistency, less downstream processing is required to remove impurities and pollutants, and less material is recycled.
    5. Benefit: lower capital and operating costs, resulting in a more competitive operation; lower lost revenue caused by downtime; less downstream capacity constraint on reactor production.
  5. Faster time-to-market. By using model-based techniques it is possible to evaluate design alternatives rapidly, integrate R&D experimental programmes with the engineering design, and start commercial production in the minimum time.
    6. Benefit: earlier revenue stream; less capital deployed; advantages of being early-to-market; more reliable start-up and initial operation resulting in improved economics.
  6. Accelerated innovation. High-accuracy predictive modelling is an invaluable tool when designing new processes and equipment, or even when making simple process improvements.
    7. Benefit: potential to increase competitive advantage leading to lower-cost or higher-value production.
  7. Easier and more reliable scale-up. Modelling is used with great effect in the scale-up of processes from laboratory to production scale.
    8. Benefit: accelerated development leading to better and more reliable process; earlier revenue stream and advantages of being early-to-market; better subsequent throughput and quality leading to more profitable process.
  8. Catalyst selection. Rigorous catalytic reactor models can be used to rank and select catalysts based on their performance "in the reactor".
    9. Benefit: Better production, with higher throughput and product quality; lower catalyst lifecycle cost; reduced downtime; reduced energy costs, leading to more profitable and competitive process.
  9. Catalyst performance monitoring. Rigorous reactor models can be used to determine catalyst activity on a daily or weekly basis, and the information used to optimise future operating conditions to maximise the life of the catalyst [see article].
    10. Benefit: Longer catalyst life; lower catalyst lifecycle cost; reduced downtime; better compliance with customer requirements, leading to more profitable and competitive process.
  10. Improved controllability. A better design, with lower design margin, generally resulting in a more well-defined operating envelope and better controllability.
    11. Benefit: More consistent quality product with reduced off-spec products and pollutatnts, leading to higher product revenue, lower energy costs, lower downstream processing costs and better environmental compliance. More flexible, profitable and competitive process.
  11. Lower capital cost. The better designs made possible by rigorous modelling, generally result in lower design margin and hence capital cost.
    12. Benefit: Lower capital deployed; less lifetime cost leading to more competitive product prices and better competitive position.
  12. Optimisation of steady-state operating conditions. A rigorous model allows easy optimisation of operating conditions such as reactor temperature and pressure, feed conditions, heating or cooling medium temperatures, etc.
    13. Benefit: Better product throughput and quality with reduced energy costs, resulting in a more profitable and competitive process.
  13. Optimisation of transient operating conditions and operating policy. A rigorous model enables you to optimise transient operations such as grade change, to minimise off-spec product and energy usage.
    14. Benefit: Reduced off-spec product resulting in higher overall production, reduced downstream processing or recycling and lower energy costs; more flexible process allowing rapid response to customer demand.
  14. Optimisation of startup policy. Similarly, it is possible to optimise, for example, startup policy, to start up in the minimum time and with minimum production of off-spec product.
    15. Benefit: Reduced process downtime; more flexible maintenance; less off-spec product and lower energy costs; higher process availability resulting in higher overall production.
  15. Troubleshooting. A rigorous model, with its ability to predict what is happening inside a reactor to a high degree of accuracy, can be used for troubleshooting of many operational problems.
    16. Benefit: Rapid response potential; reduced environmental or safety impact; improved throughput and product quality resulting in better process profitability.
  16. Hot-spot determination. A rigorous model of a catalytic reaction process, particularly when linked to a CFD model for accurate modelling of the system hydrodynamics, can be used to predict the formation and location of potential hotspots.
    17. Benefit: extended catalyst life with reduced downtime; reduced catalyst lifecycle cost; improved throughput and product quality, all resulting in better process margin.

    'Soft' benefits: knowledge, understanding and integration

    There are a number of 'soft benefits' to modelling of reaction processes that should not be underestimated:

    • Greater understanding of the process and its operation. Modelling significantly increases process understanding, allowing better-informed decisions to be taken at all levels of design and operation.
    • Greater knowledge. The model-based data analysis and model validation exercises required to build a validated reactor model – in particular determining the definitive reaction set and establishing accurate kinetic parameters – lead to increased corporate knowledge of the process.
    • Integration of R&D and Engineering Design. The collaboration required for this modelling and validation effort, and the design of related experimental programmes, leads to a close integration of experimental work with the engineering modelling effort.

    This means that experimental work is targeted at design, and design requirements can be used to guide experimental work.

    This relationship can be formalised through the use of model-based experiment design to determine the optimal set of experiments, and the general application of Model-Based Innovation techniques.

  17. More effective use of experimental data. For the reasons outlined above, experimental data can be leveraged and enhanced through its application in modelling
  18. Familarity with the tools. Having access to, familiarity with, and understanding of the right toolset is critical for successful application. Without the right tools, the results cannot be achieved.
  19. Confidence to innovate. The existence of a tool that provides accurate predictive information is a significant confidence booster when innovating.