Cover: Full Scale Plant Optimization in Chemical Engineering, 1 by Zivorad Lazic

Full Scale Plant Optimization in Chemical Engineering

A Practical Guide

 

Živorad R. Laziċ

 

 

 

 

 

Logo: Wiley

Preface

                                               “Let your systems learn the wisdom of age and experience”

It is well known that chemical engineers are involved in each step of the process development (lab‐scale and pilot‐scale) and later in the scale‐up and full‐scale plant process improvement. So far, there are three powerful methodologies/tools for chemical engineers with wide application in industry:

  • Design of Experiments – DOE
  • Evolutionary Operation – EVOP
  • Data Mining using Neural Networks – DM

The objective of this new book is to compare all three methods in full‐scale plant optimization applications and to focus on a simple but powerful technique which provides the experimental tools for full‐scale plant optimization. It is called Evolutionary Operation or EVOP.

Chapter I provides the basic principles necessary for a simple understanding of the difference between these three methodologies.

Chapter II covers only two‐ and three‐factor full factorial designs from the Design of Experiments because of the subject of this book. DOE experiments are very efficient in the lab or pilot plant but NOT in the full‐scale process. There are two main reasons for that:

  • An owner of the large‐scale process would hardly accept DOE experiment. To detect significant factor's effect in industrial process, a large change in control factors is required, and that on the other hand will produce off‐spec product.
  • Also replications required by DOE to reduce noise will produce even more off‐spec products.

Chapter III describes theory and application of Data Mining using the Neural Networks modeling tool. In the last twenty or more years, with more data historians installed in process industry, Data Mining, using neural network software, is widely used for industrial process optimization. The main problem with this approach without experiment is static operation of the plant, which means running the plant with almost no change in process factors. Standard Operating Procedures keep factors constant for a very long time. A greater change in process factors is not allowed. If it happens, it will produce off‐spec product. This means, all collected data are in very narrow experimental space range, and usually local or global optimum of the process is out of that range.

An analysis of historical data typically has only 10% to 20% chance of success, despite the fact that hundreds or thousands of data points may be available.

Chapter IV, DOE and Data Mining disadvantages, strongly suggests reusing Evolutionary Operation – EVOP experimental technique. Box G.E.P proposed a special Operation as a technique for improving industrial productivity. Its basic philosophy is that it is nearly always inefficient to run an industrial process to produce a product alone; a process should be run so as to generate a product plus information on how to improve that product. The procedure consists of carefully planned cycle of minor variants on the standard work process. The routine procedure consists of running each of the variants continually repeating the cycle. Usually the effects of these deliberate changes in the factors‐variables are masked by the large errors inherent in large‐scale production units. However, since production will continue anyway, a cycle of variants, which do not affect production significantly, can be run almost indefinitely. Because of constant repetition the effect of small changes can be detected. The wisdom of the age and long experience suggests that EVOP tools help chemical engineers dealing with two different objectives:

  • Scale‐up from lab and pilot‐plant to full‐scale operation and “fine tuning” of large‐scale production.
  • Once the optimum is achieved at certain point of time, it is going to be a moving target and it is very hard or impossible to use tools like DOE and DM due to variability of raw materials quality, energy supply fluctuation, tooling wear, gradual equipment misalignment, shifts in ambient temperature and humidity, corrosion, decreasing heat transfer, aging equipment and instrumentation, aging catalyst and scale build‐up, etc.

Chapter V describes theory and applications of five different EVOP methods including Box EVOP, with numerous examples and simulations to compare efficiency:

  • Box Evolutionary Operation – BEVOP
  • Rotating Square Evolutionary Operation – ROVOP
  • Random Evolutionary Operation – REVOP
  • Simplex Evolutionary Operation – SEVOP
  • Quick Start EVOP – QSEVOP.

These simulators are the perfect tools for training operators in different EVOP techniques. Also they could be used to run full‐scale plant optimization. In meantime, a special software “EVOP Engine” is under construction and will be released after the book is published.

Research and development scientists and engineers may find the book helpful in optimizing various processes to be more efficient, less energy intensive, less time consuming, more reliable, and less wasteful of raw materials.

This book has come into being a product of many years of research activities at Military Technical Institute, Belgrade, and long experience in process and product development with large‐scale production, including Lenzing Fibers Corporation, Austria; MacDermid, TN, US; and BASF Catalysts LLC., GA, US. The author is especially pleased to offer his gratitude to Helena Smuckler and Anica Lazic for editing of the manuscript. I express my special gratitude to Milica Pojiċ. for helping in a search for the literature.

 

Petrovac, Montenegro
June 2021

Živorad R. Laziċ

Biography

Živorad R. Laziċ is the author of Design of Experiments in Chemical Engineering: A Practical Guide, published by J. Wiley in January 2004. He has produced a unique, “how to do it,” a practical guide for the statistical design of experiments. It is the ideal book for the industrial scientist or engineer who wants to take advantage of DOE techniques without becoming a statistician. Basic statistical ideas are presented clearly and simply with numerous examples. This is one of the few books that are practically suited for self‐study by a busy technologist, engineers, and scientists. He is a Certified Six‐Sigma Black Belt professional with interests in advanced statistical tools, Design of Experiments (DOE), Statistical Process Control (SPC), Evolutionary Operation (EVOP), and process modeling via application of neural networks.

Živorad received his B.S., M.S., and Ph.D. in chemical engineering from the University of Belgrade, in Belgrade, Serbia. He began his career with Viscosa‐Loznica Corporation (1975–1979). After that he worked for Military Technical Institute (VTI), Belgrade, where he took a position as Head of R&D Department for composite rocket propellant. He was trained in Hercules, McGregor, TX, in 1982 and 1986. Lazić moved abroad in 1994 due to the war which took place in former Yugoslavia.

He spent more than six years as Vice President for process and product development in P.T. South Pacific Viscose, Indonesia, subsidiary of Lenzing Group, Austria. After he moved to USA in 2001, he worked as Quality Assurance manager at Lenzing Fibers Corporation, Lowland, TN, and Black Belt Six Sigma engineer at MacDermid Graphics Solutions Morristown, TN.

From 2008 Živorad worked as a Senior Research Scientist at BASF Catalysts LLC., Gordon, GA., USA. He retired from this position in 2014.