KINPTR model

The greatest barrier in the application of the Multicomponent Fowler-Guggenheim or Bragg-Williams Lattice gas model to, a practical situation like Pet-reforming, is the absence of experimental interaction parameters. In the simulations of the earlier sections, representative values were used. In general, for an n component system, we need to fix n(n+l) / 2 interaction parameters of the symmetric W matrix (91 for a 13 component Model ). Mobil has used successfully a 13 lump KINPTR model(5), which essentially uses a Hougen-Watson Langmuir-Hinshelwood approach. This results in a psuedo-monomolecular set of reactions, which is amenable to matrix analysis. 

Byung C. Choi, KINPTR (Mobil s Kinetic Reforming Model) A Review of Mobil s Industrial Process Modeling Philosophy... 

KINPTR (MOBIL S KINETIC REFORMING MODEL) A REVIEW OF MOBIL S INDUSTRIAL PROCESS MODELING PHILOSOPHY... 

Over 30 man-years of effort were involved in developing the model, which is named KINPTR, an acronym for kinetic platinum reforming model. Since its development, KINPTR has had a major impact in Mobil s worldwide operations. It can be accessed by personnel at each of Mobil s locations throughout the world. Input requirements are simple and convenient making it very user friendly. Only feed characteristics, product quality targets, process configuration information, and process conditions are required for input. Output is informative and detailed. Overall and detailed yields, feed and product properties, and reactor performance data are given in the output. 

In this chapter the following topics will be reviewed KINPTR s start-of-cycle and deactivation kinetics, the overall program structure of KINPTR, the rationale for the kinetic lumping schemes, the model s accuracy, and examples of KINPTR use within Mobil. As an example, the detailed kinetics for the C6 hydrocarbons are provided. 

KINPTR is an overall process model thus it simulates all important aspects of the process which affect performance. In order to lay a foundation for upcoming discussions related to KINPTR development, the important aspects of naphtha reforming—chemistry, catalysis, and reactor/hardware design—will be summarized. More extensive reviews are available in the literature (1-3). 

Start-of-cycle kinetic lumps in KINPTR are summarized in Table V. A C5-light gas lump is required for mass balance. Thirteen hydrocarbon lumps are defined. The reforming kinetic behavior can be modeled without splitting the lumps into their individual isomers (e.g., isohexane and n-hexane). Also, the component distribution within the C5- lump can be described by simple correlations, as discussed later. The start-of-cycle reaction network that defines the interconversions between the 13 kinetic lumps is shown in Fig. 9. This reaction network results from kinetic studies on pure components and narrow boiling fractions of naphthas. It includes the basic reforming reactions... 

Fig. 23. KINPTR process model description (with module names).

In commercial aging simulations, KINPTR s deactivation model is used to predict cycle lengths (time between catalyst regenerations) and reactor inlet temperature requirements with time on stream to maintain target reformate... 

KINPTR simulations of commercial reforming (Table XVIII) will be used in this section to demonstrate process sensitivity. In the base case, a full-range Mid-Continent naphtha (55 wt. % paraffins) is reformed to a constant octane of 90 R + 0 over the entire cycle. With a reactor pressure of 1695 kPa and a 7.2 H2 recycle ratio, the start-of-cycle reactor inlet temperature to achieve target octane is predicted to be 759 K. The deactivation simulation shows that it would take about 1 year to reach the end-of-cycle temperature of about 798 K. The start-of-cycle C5+ yield for this case is 86 vol %. The model predicts that the yield would decline by 4.8 vol % over the cycle. 

KINPTR is used several thousand times a year for both research and commercial reformer estimates. The model has four principal uses commercial monitoring, reformer diagnostics, optimization, and research and development guidance. 

KINPTR is also used extensively for commercial planning guidance and reformer operation optimization. The model has been used to improve linear program accuracy for short-range refinery planning and crude oil supply and distribution studies. It is also used to optimize reformer economics by proper selection of operating conditions within refinery constraints. 

We wish to acknowledge C. D. Prater, J. J. Wise, and V. W. Weekman, Jr., for their valuable guidance and critical support of the KINPTR research and development program. Their strong commitment, both technically and managerially, to the development of a reforming process model based on fundamental reaction kinetics was instrumental to KINPTR s success. 

We also wish to acknowledge the efforts of many others who contributed to KINPTR D. G. Tajbl and K. A. Hill for their contributions to the development of the kinetic data base and various aspects of the kinetics J. C. W. Kuo, S. B. Jaffe, and W. H. Speaker for their key software contributions to the KINPTR process model J. S. Hicks for his efficient numerical algorithms and the many technicians and analytical personnel whose dedication to generating very accurate kinetic data ultimately led to the successful development of KINPTR. 

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