Simulation experiments for maximising the availability of a commercial octene production facility

RF Rossouw,PD Pretorius,RLJ Coetzer

doi:10.5784/26-1-86

Abstract

Overall availability of a chemical process is of critical importance in industry. In this paper we evaluate the process design factors that influence the availability of a new chemical production facility by performing computer experiments on a stochastic simulation model. Experimental designs commonly used in the Design and Analysis of Computer Experiments (DACE) and Classical Design of Experiments (DOE) are evaluated and compared for application by means of simulation experiments. Furthermore, response surface and kriging models are evaluated for the approximation of the input-output relationships. The most accurate experimental design by approximation model combination is used to explore the design space, both in terms of the overall availability and the percentage time offline. We illustrate how the design and analysis of simulation experiments (DASE) are used for minimizing the risks in the design of a new 1-octene production facility in terms of maximising the overall availability and minimizing the percentage time offline simultaneously.

Highlights

Higher alpha olefins, such as 1-octene, are used commercially as co-monomers for the production of, amongst other things, linear low-density polyethylene
The optimal design by metamodel combination was used to explore the design space, both in terms of the overall availability and the percentage time offline, and valuable insight was gained about the industrial system
Two approximation models for the input-output relationship are compared namely response surface models and kriging models

Summary

Introduction

Higher alpha olefins, such as 1-octene, are used commercially as co-monomers for the production of, amongst other things, linear low-density polyethylene. The problem with conventional linear alpha olefin technologies is that, in addition to 1-octene, a mathematical distribution of less useful olefins is produced. The production of 1-octene via the selective tetramerisation of ethylene is of great commercial value. Perhaps the best known homogeneous catalyst system for the tetramerisation of ethylene is that developed by Phillips Petroleum Company which consists of a chromium source, 2,5dimethylpyrrole and an alkylaluminium as activator. A number of other chromium-based homogeneous catalyst systems have shown promise in this regard [3].

Objectives

Methods

Conclusion