Budny, 10:00
R03
THE “RIGHT” CHOICE
Connor Bassett (cjb114@pitt.edu)
The most common mode of flow is called “dead-end
mode.” In dead-end mode, flow is directed perpendicular to
the membrane, so the particles and other forms of matter
being filtered out remain on the surface of the membrane,
while the water molecules pass straight through the
membrane. Other methods such as cross flow (flow is directed
tangential to the membrane) exist but are less common due to
higher operating costs and the more complex equipment
needed for these methods. [3]
BACKGROUND
Membrane filtration is a method of water processing that
uses a thin layer of material to separate compounds by
physical and chemical properties by applying a force across
the membrane [1]. These membranes have a wide range of
applications, including filtering wastewater, saltwater, and
source water to produce potable (consumable) water. The use
of these membranes would allow our society to remove the
contaminants from existing freshwater and to produce
freshwater from salt water. Membrane filtration was first
introduced in the 1960’s, but has not become a cost effective
method until recently. It is a technology that is continuing to
improve and become more cost efficient. [2]
THE BAD AND THE UGLY
As appealing as all of these advantages of membrane
filtration are, we must consider the various side effects of the
technology. The membranes, like any filter, must be cleaned
to maintain efficiency. This is comparable to a dryer filter.
When the filter is not cleaned before doing a load of laundry,
the laundry will not be dried as well as it would be if the filter
was clean. If the filter is not cleaned after several loads, the
laundry will be wet when you take it out. This occurs because
as the amount of accumulated material increases, the
efficiency of the filter decreases. The same goes for
membranes. For a longer period of time in which the
membrane is not cleaned, the membrane’s water processing
efficiency will proportionally decrease. Now we reach the real
issue, what is done with the material that is cleaned off of the
filter? In the case of the dryer, we just scrape the lint off and
throw it in the trashcan, but it can also be practically used as
a fire starter, as it is very flammable. We must ask ourselves,
is it ethically acceptable to just dump what is removed in a
landfill? Membranes require intensive chemical cleaning to
maintain optimal operation, which produces a hazardous byproduct. It should be noted that traditional treatment processes
also produce various by-products.
There are several different kinds of membranes, each of
which removes particles of ascending size. The membranes
are named by the processes they perform. “For example,
microfiltration (MF), ultrafiltration (UF), nanofiltration (NF),
and reverse osmosis (RO) are four membrane processes that
use pressure to transport water across the membrane. MF
membranes are capable of removing suspended particles,
colloids, and bacteria, while UF and NF membranes can
remove macromolecules/natural organic matter and
dissociated acids/divalent ions/sugars/pharmaceuticals,
respectively. RO membranes retain many solutes as water
permeates through the membrane.” [1] A diagram
demonstrating this process is shown below.
WHERE DOES IT GO?
What is to be done with these by-products? Where do we
put the substances filtered out, or the chemicals that are used
to clean them? How do we handle such matter? Let us
consider another comparison. Before the invention of the
combustion engine, gasoline was considered a useless byproduct of oil refining. What was done with it? It was burned
off in holding tanks the size of small lakes. A limited resource
that only a few years ago, we paid over 4 dollars a gallon for
Figure 1 [1]
Membrane Classifications Based on Pore Size
Used in series, these membranes could take wastewater,
essentially what you flush down the toilet, and produce
potable water of a higher quality than what comes out of the
average faucet.
University of Pittsburgh, Swanson School of Engineering
2014-10-28
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Connor Bassett
it. How do we know that we are not faced with the same
situation here? What if these membrane filtration by-products
are a very valuable resource that we could just be throwing
away? Even if these by-products are not a valuable resource,
we must ask ourselves, is it acceptable to just throw them in a
landfill as many water treatment by-products are? What are
the consequences of doing so? Additionally, what
consequences are negligible, and how should we make such a
decision? The person most often responsible to make such a
decision when implementing such a filtration process is the
engineer. It is for this reason that codes of ethics exist that
engineers are legally required to follow. The engineer must
make a decision that will yield the greatest benefit with the
least amount of consequences possible. The engineer must
take into account the environmental impact (this is why
environmental impact reports exist for such projects), the
impact on the lives of humans, and the long term
consequences of their decision.
treatment plant hire a firm which specializes in the cleaning
of such membranes, to clean the membranes on regular
intervals. This option would be close to the same cost of
treating the material at the plant, but would spread the cost
over a longer time period. The cost of this option would
decrease over time as the technology for treating the byproducts improved, as such a company tends to stay on the
cutting edge, while if doing the treatment at the plant the same
outdated machines will be used until the next upgrade.
THE DILEMMA
After work that day, I call my dad. As an award winning,
very reputable civil engineer, he is more than qualified to
discuss the subject. However, more importantly, he seems to
always know what to do in a questionable situation. He first
tells me to look at the codes of ethics for the societies of
engineers which I am a part of, as they set the rules of what
the engineer must do in such a situation. Then he continues
that I must meet budget if I wish to maintain upward mobility
within the company. He leaves me with the advice that in any
situation, there is an outcome that is favorable to all parties,
even if it comes at a great cost. [8]
I first take the issue to my boss. He tells me that back when
he was where I am, they would have just dumped it over the
bank and forgot about it. However, as that is not an option, he
leaves me to make the decision, but it must meet budget.
Faced with a rapidly approaching deadline, I must make a
choice, but I do not know what choice is the right one.
WHAT DEFINES ACCEPTABLE?
Let me propose a situation in which I am faced with the
dilemma of the disposal of these dangerous by-products of the
membrane filtration process. I am a young project manager
and process engineer in charge of my first wastewater
treatment process, an upgrade of a 5 MGD plant serving a
nearby town, which includes a membrane filtration system.
To get this job, my firm bid an amount that despite the
warnings of myself and the other process engineers in the
office, was quite low. I am currently wading through the
design stages of the process, having a very hard time meeting
the budget for the project. At project meetings every week, I
express my concerns to my superiors, who reply that budget
must be met, even if corners must be cut. Despite my efforts
to cut costs by cutting out all of the unnecessary atheistic
features, the threat of not meeting budget looms overhead.
With this advice in mind, I set out on a hike. I have made
this particular trip many times before, with a question, issue,
or dilemma heavy on my shoulders. I head to the cliffs high
atop Cove Mountain across the creek from my house. No
matter how difficult the issue, no matter how sticky the
situation, the cliffs will answer. There is something about
sitting there, about 1600 feet above the bottom of the valley,
watching life go on below, that removes you. It both mentally
and spiritually removes you from everything that defines our
daily lives. Many choices that have brought me to where I am
today have been made here. After sitting here sometime, I am
sure of the answer.
Eventually, during the design stages of the membrane
system, I am faced with the decision of what is to be done
with the material which accumulates on the filters, and the
chemicals used to clean them. There are only a few options
that are economically feasible for this project. The first option
is simply taking the by-products of the process, as is usually
done with the large particles and grit, to the landfill and
dumping them there. However, this material is much more
reactive and hazardous than standard treatment process grit.
Another option would be to add another treatment process
within the plant that would take the by-products, chemically
treat them, and produce neutral compounds suitable for
disposal. This option is the most thorough of all, but is
extremely costly, and would put the project well over budget.
A final option is to have the municipality which owns the
Returning home, I read the codes of ethics as suggested by
my father. The first of the fundamental canons of both the
ASCE and NSPE codes of ethics state that “Engineers shall
hold paramount the safety, health and welfare of the public”
[4] [5], The ASCE code of ethics continues that “Engineers
should seek opportunities to be of constructive service in civic
affairs and work for the advancement of the safety, health and
well-being of their communities, and the protection of the
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Connor Bassett
environment through the practice of sustainable
development.” [5] In relation to my dilemma, the last part is
of paramount importance. To dump the untreated by-products
into a landfill would put the environment at risk and would
not be a sustainable practice, therefore violating the code of
ethics.
human beings. Such a move would be cutting a hypothetical
corner in the job, which is not virtuous or effective, and
therefore should not be done. Choosing to have another firm
handle the cleaning would cost more, but would have the
greatest benefit without any environmental impact.
In this case, I would chose to have a firm clean the
membranes for the plant. It would eliminate the risks of
dumping reactive waste into a landfill, making it an ethically
acceptable alternative. Having another firm clean the
membranes would spread the cost of this additional step of the
treatment process over time, allowing the project to meet
budget. It would cost the municipality a greater amount of
money than dumping the by-products. However, as the only
ethically acceptable option with the greatest benefit at the
least cost, it is the obvious choice.
WORD FROM THE WISE
Engineers around the globe are faced with dilemmas such
as the one I proposed every day. There is no way to
completely avoid such situations, and therefore there exists
resources at the engineer’s disposal to help them make the
right decision. In addition to these sources, any engineer has
a network of other engineers to refer to for aid. For any
engineer faced with a decision, problem, or dilemma similar
to the one I proposed, I have a method of facing the problem
that I would suggest them to consider. First, thoroughly
analyze the situation. What factors affect the situation? Who
or what is involved? What is at risk? Then proceed to consider
every possible option, and the outcome that each would
produce. Find the benefits and costs of each outcome. Finally,
choose the outcome with the greatest benefit at the least cost
that is ethically acceptable. To find what is ethically
acceptable ask yourself a few questions. Would I do such a
thing to myself or my own property? In decisions such as this
before, what choices were made that were regretted? For this
question, consider the use of DDT, which had many benefits
as a pesticide, but had a huge toll on the populations of many
species, such as shellfish and birds. The old saying goes
“hindsight is 20-20” and therefore I would encourage
anybody in such a dilemma to look into the past at previous
decisions that the effects of which can now be seen to
determine what they should do.
A QUESTION OF ETHICS
As the designers of almost every piece of technology, our
infrastructure, and many facets of science, engineers have an
enormous impact on our lives. When engineering is done
right, it contributes greatly to the quality of life. When an
engineer makes a mistake, its impact can be great. In his
article Ethics in Engineering, William A. Wulf phrased it
“Because of the enormous impact of engineers on individuals
and society, we also have deep moral and ethical
responsibilities”. [6] It is because of this great deal of this
responsibility held by engineers that we are legally required
to follow codes of ethics. We must, as I did, make our
decisions considering the impact of them on all that is
involved. However, ethics in engineering do not only involve
the impacts of a decision by an engineer. It ranges from this
subject to issues such as corruption, interactions between
engineers, and professional development. These codes are
intended to eliminate corruption, malpractice, and dangerous
actions. If every engineer perfectly abided by their respective
codes of ethics, our industry would be completely efficient.
CONCLUSION
Considering the massive amount of influence that
engineers have over our lives, they must be held accountable
for their actions. Regardless of the situation, as long is there
an ethical issue in question during the making of a decision,
the engineer must be able to respond in the appropriate
manner. The easiest, cheapest, or most beneficial choice is not
necessarily the best choice. There can be other impacts and
consequences of the decision that must be taken into
consideration. Engineers should know and abide by the codes
of ethics for their respective societies. If every engineer did
so we would have an industry without corruption and other
forms of malpractice. However, no single man is fully capable
In making my decision in regard to the dilemma I was
faced with, I found guidance to the answer in an article by
Samuel C. Florman. A particular piece which guided me
states “Engineers should be constantly aware that their fellow
citizens are relying upon them. As a consequence, if they do
their jobs well, they are acting more than competently. In
serving their fellow human beings, and serving them well,
they are acting righteously. Reliability is a virtue. Therefore,
the conscientious, effective engineer is a virtuous engineer.”
[7] Choosing to simply dump the remains from the filtration
process would be to ignore the effects it could have on other
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Connor Bassett
of defining what is right and what is wrong. For this reason,
we have set codes of ethics that engineers must abide by.
[10] NSPE Board of Ethical Review. "Public Health and
Safety-Delay in Addressing Fire Code Violation." (n.d.): n.
pag.
Http://www.nspe.org/sites/default/files/BER%20Case%20N
o%2013-11-FINAL.pdf. National Society of Professional
Engineers, 30 Apr. 2014. Web. 26 Oct. 2014.
http://www.nspe.org/sites/default/files/BER%20Case%20No
%2013-11-FINAL.pdf
REFERENCES
[1] Yoon, Yeomin. "Membrane Filtration." - IWA Water
Wiki. International Water Association, 30 Nov. 2012. Web.
27 Sept. 2014.
http://www.iwawaterwiki.org/xwiki/bin/view/Articles/Mem
braneFiltration
[2] García, Dora. 2001. “Fundamentals of Membranes for
Water
Treatment” Texas Water Development Board. Texas Water
Development Board, 9 Oct. 2012. Web. 28 Sept. 2014.
https://www.twdb.texas.gov/publications/reports/numbered_
reports/doc/R363/C6.pdf
[11] "What's the Angle?" Texas Tech University. National
Institute for Engineering Ethics, n.d. Web. 26 Oct. 2014.
http://www.depts.ttu.edu/murdoughcenter/products/cases.ph
p.
ADDITIONAL SOURCES
[3] Wang, Lawrence K., Chen, Jiaping Paul, and Hung,
Yung Tse, eds. “Handbook of Environmental Engineering :
Membrane and Desalination Technologies”. Totowa, NJ,
USA: Humana Press, 2008. ProQuest ebrary. Web. 27
September 2014.
http://site.ebrary.com/lib/pitt/reader.action?docID=10434859
Duke, Mikel, Zhao, Dongyuan, and Semiat, Rafael, eds.
New Materials for Sustainable Energy and Development:
Functional Nanostructured Materials and Membranes for
Water Treatment. Somerset, NJ, USA: John Wiley & Sons,
2013. ProQuest ebrary. Web. 28 September 2014.
http://site.ebrary.com/lib/pitt/reader.action?docID=10674814
[4] "Code of Ethics." National Society of Professional
Engineers. National Society of Professional Engineers, July
2007. Web. 24 Oct. 2014.
http://www.nspe.org/resources/ethics/code-ethics
ACKNOWLEDGMENTS
[5] Flavell, Eric L., P.E. "Code of Ethics." Code of Ethics.
American Society of Civil Engineers, 23 July 2006. Web. 26
Oct. 2014. http://www.asce.org/Ethics/Code-of-Ethics/
I would like to thank my father, Britt Bassett, a licensed
professional engineer with extensive experience in the
process engineering of water treatment plants, for his help
with choosing the topic of this paper and pointing me in the
right direction for research. I would also like to thank Ben
Stutz, Sam Cooke, Orin Keel, and Drew Gordish for their
insightful discussions about this paper. Finally, I would like
to thank Rebekah Shearer for assisting in proofreading my
paper.
[6] Wulf, William A. "Engineering Ethics." News Rss.
National Academy of Engineering, Fall 2002. Web. 26 Oct.
2014.
https://www.nae.edu/Publications/Bridge/EngineeringEthics
7377/EngineeringEthicsEditorial.aspx.
[7] Florman, Samuel C. "Engineering Ethics." News Rss.
National Academy of Engineering, Fall 2002. Web. 26 Oct.
2014.
https://www.nae.edu/Publications/Bridge/EngineeringEthics
7377/EngineeringEthicsTheConversationwithoutEnd.aspx.
[8] B. Bassett. (2014, Oct. 23). Conversation
[9] Disposing of Toxic Waste" Online Ethics Center for
Engineering 3/30/2006 National Academy of Engineering
Accessed: Sunday, October 26, 2014
www.onlineethics.org/Resources/Cases/Toxic.aspx
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