Modularización

Modularization
ZAHEER I. MALIK and RONALD D. KEY
The Pro-Quip Corporation
A Subsidiary of Linde AG
Tulsa, Oklahoma
A Practical and Economical Construction Technique for Process Systems in the Chemical,
Petrochemical, Gas Processing, and Oil Refining Industry.

Photo: Modular Construction employed in an Ethylene Recovery Unit built by Pro-Quip for Mobil Chemical in Houston, TexasABSTRACT
The following paper outlines the aspects of using the
modular construction concept Each point is detailed from a
general perspective so that it may be applied to any industry.
Major points discussed include engineering, design,
equipment size, type, and instrumentation.

Unfortunately, the space available for the installation of new
units is still limited as most existing facilitieshave
established and fully developed plot areas, thereby creating a
challenge for both the client and the engineering contractor.
Pro-Quip recognized the need for operating and
maintenance accessibility combined with the challenge of
limited plot space and over the years has endeavored to
change the image of the modularized process units by
developing modular design concepts in such mannerthat
safety, maintenance and ease of operation are given prime
consideration. In this concept modular construction is not
simply putting the most in the least space, but involves a
sophisticated art requiring special expertise to engineer,
design and fabricate process facilities compatible with
facility operator needs.

INTRODUCTION
Over the years the notion of modularized processing unitsinvariably has conjured up images of equipment packed into
the smallest possible area with little concern for the
necessary access for safety. proper operation, and
maintenance of the unit. These concerns, which more often
than not are justified, have been further perpetuated over the
years by many skid fabricators who, in their efforts to
provide low-cost processing units for installationin the
limited space often available, have built them in just such
fashion.

Modularized construction has many positive aspects to
consider. The modules contain the equipment, piping, heat
tracing, electrical instrumentation systems, specialized

I

Copyright Linde BOC Process Plants LLC
All Rights Reserved

FACTORS AFFECTING MODULAR DESIGN

coatings, fire protection, ladders, andplatforms. Modules can be
horizontal, vertical, single level, or multi-level depending on the plot
space, equipment, and required piping configuration. The optimum
split of modular & field construction efforts is determined for each
individual project based upon such factors as local labor costs,
transportation limitations and schedule.

The following factors affect modular unit design:
1.Process Engineering
2. Equipment Selection
3. Equipment Layout
4. Piping

As one may surmise, a true modular project has more sophisticated
engineering and design requirements than a field erected project.
Fortunately, the higher design costs can be off-set by minimizing
downstream equipment erection that is more costly than shop
fabrication work. Many, but not all, process applicationsare good
candidates for modularization. The preliminary screening factors are
equipment size and overall system complexity (i.e., quantity of pipe,
valves, instrumentation, tracing, insulation, and other auxiliaries which
interconnect with major equipment items). For an ideal modular project,
all equipment will fit on a structural module which can be shipped,
while providing adequate spacefor the installation of all piping, valving,
instrumentation, insulation, fireproofing, and electrical systems. A plant
should be modularized if it can be engineered, designed, shop assembled,
tested, transported, installed, and commissioned at less cost and time than
on-site construction would afford and where very close control of quality
or other similar factors during the course of...