02-03-2013, 03:35 PM
Hands-On Chemical Engineering Senior Design: The Evolution from Paper to Practice
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Abstract
Historically, the senior design sequence in chemical engineering has differed from that of
other engineering disciplines due in large part to problems of scale: a team of mechanical
engineers can reasonably design and produce a prototype stapler, for example, but it is
beyond most schools’ capabilities to have the chemical engineers both design and
“produce” a petrochemical plant. Therefore chemical engineering design has focused
primarily on the “paper” aspects of design, encompassing unit operations, economics,
planning, and process simulation. This approach unfortunately misses out on some
potentially important lessons that can be learned from actual process implementation,
such as the need for process flexibility and the challenges of controlling a system to the
five decimal places that were so easily specified in the paper design.
This paper describes the seven year long evolution at Bucknell University towards a
hybrid paper/practical senior design sequence where each team must physically solve a
real chemical engineering problem, often from local industry, by the end of the year.
Solutions to the problems must be demonstrated experimentally, and have ranged from
developing and operating bench- and pilot-scale processes to design and development of
novel process equipment to developing novel process conditions for existing equipment
to result in superior products. Both survey and direct assessment results demonstrate
positive student outcomes from this version of the course sequence. This paper will also
reflect upon both the plusses and minuses of this approach from the faculty perspective.
Introduction
Senior design is the capping experience in undergraduate chemical engineering
education, wherein students undertake a design process compiling elements from each of
their undergraduate courses. Until recently a course of this nature was specified by
ABET. While ABET current rules are less proscriptive, there is general agreement
among Chemical Engineering programs that senior design continues to be an important
and required course. The common goals of this course are for students to realize the
design of a chemical facility, incorporating economics, process simulation, control.
History
The alteration of the senior design sequence was evolutionary, and can be broken into
three periods. First, the “traditional” sequence (1998-99 and earlier) centered on a paper
design of a styrene monomer plant only. In the transitional year (1999-2000) the paper
design of the future experimental work was considered by one team. Finally, the current
design sequence came into being in 2000-01, and involves a first semester paper design
on a variable theme as well as the second semester practical design.
The historical development of this departure from tradition starts in Fall 1998, when Dr.
Maneval was approached by a local soap manufacturing facility. While the original
project fell through, Maneval realized that the process had numerous features that would
make it desirable as a practical experience in process design. The process is relatively
simple and safe, utilizing process conditions that are realizable in undergraduate
laboratories with existing equipment and safety procedures. In spite of this apparently
simplicity, the process is also sufficiently complex in terms of the unit operations
required (heating, reacting, multiple separation, washing, drying, and forming steps) to
provide a rich variable space for design. He began taking steps to test this possibility,
working with numerous undergraduate research students (J. Ward, C. Caputo, M. Bucher,
C. Gibson, J. Grimley, D. Daycock, A. Jewel, L. Spagnola, and others) to test this idea.
Methods
Second semester design is a radical departure from previous versions of the course. The
overall goal of the semester is for students to construct and operate either a process or
experiments in solution of a real problem. A key feature of this course is that student
assessment is based significantly on the actual operation of their final project; the best
idea in the world will not get a good grade unless they actually make it work in the lab,
something tangible must be produced. Projects take a wide variety of forms, but all
incorporate key elements of project management, experimental design, data analysis,
simulation, economics, and laboratory construction and experimentation. Sample
projects and customers are shown in Table 2. Figures Y1, Y2, and Y3 show students
with their final resulting processes.
Results and Discussion
The success of the new senior design sequence is judged in two ways. First, through
student course evaluation surveys. This incorporates our most complete data set, and
shows clear impact as a result of the course change. Second, instructor observations and
reflections are included. While this is understandably a qualitative assessment, it
provides a richness of information needed for other schools considering such a change.