Page 25 - Design of Simple and Robust Process Plants

8 Chapter 1 Introduction
The conclusion is that the profit on a project is strongly influenced by the DFC and
therefor simple designs leading to low cost designs will have a strong economic
interest of the businesses.

1.3
Design Philosophies

The realization of the design objectives for a 21st century plant requires a different
approach to process design. Therefore, design philosophies have been developed
(see below), which are elucidated in greater detail in Chapter 3. Prerequisites for the
application of the design philosophies are: an integrated modeling environment; the
properties of the components; and models of chemistry and phenomena.
Ten design philosophies were developed and brought forward from different view-
points, and include:
. simple and robust process plants (Koolen, 1998);
. world-class manufacturing (Schonberger, 1986); and
. inherently safer and environmental sound chemical processes.

Simple and Robust Process Plants Perspective

1.3.1
Minimize Equipment and Piping

Most plants have an excess of equipment. Often, equipment can be completely
eliminated or combined in function with other equipment. These pieces of equip-
ment are selected by applying a stepwise logic performed during design. A break-
through in the way of thinking is required to achieve this simplification step, while
the process technology to achieve this, is within reach.

1.3.2
Design for Single Reliable and Robust Components Unless Justified Economically or
from a Safety Viewpoint

This philosophy needs to be applied consistently to meet the objective of simple and
robust design. Currently, most designs are based on the assumption that compo-
nents are unreliable, and therefore redundancy is considered by default. This leads
to spare provisions such as pumps, reactors or reactor systems, double or triple
instruments, safety devices and others. Currently, the design of the individual com-
ponents is very reliable, but many failures are caused by wrong component selec-
tion, installation and operation practices. Reliability data and reliability engineering
techniques are available today to support and quantify the single component design
philosophy (this will be discussed later).