labreport style guide

8/16/2019 LabReport Style Guide

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1©2016 School of Chemical & Biomolecular Engineering Georgia Institute of Technology

STYLE GUIDEUNIT OPERATIONS/BIOPROCESS UNIT OPERATIONS:

ChBE 4200/4210

Summer 2016

Table of Contents

Background ...................................................................................................................... 2

Format, Font, and Word Limits ....................................................................................... 4

Abstract ............................................................................................................................ 5

Introduction ..................................................................................................................... 8

Theory ............................................................................................................................ 11

Experimental Apparatus and Procedure ........................................................................ 14

Results and Discussion .................................................................................................. 17

Conclusions & Recommendations................................................................................. 21

References ..................................................................................................................... 24

Nomenclature................................................................................................................. 29

Appendices .................................................................................................................... 31

Lab Report Examples .................................................................................................... 32

Appendix A: Scientific Writing & Format Specs ......................................................... 47

Appendix B: In-Text Citations ..................................................................................... 53

Appendix C: Writing - Style & Grammar .................................................................... 54

Appendix D: Other Standard Writing Conventions ..................................................... 56

Appendix E: Tables and Figures ................................................................................... 64

Appendix F: Transitional Words and Phrases ............................................................... 69


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Background

As a chemical engineer, communicating the process and results of your experimental

work is as important as the work itself. In fact, if you do not share your process and results with

the larger community (i.e., your co-workers, your boss, your professional peers), the work itself

ceases to have value. A written lab report is one way of documenting and disseminating the

details of your research (oral reports are, of course, another). However, just “writing up” an

experiment is not adequate; the quality of the writing matters, as does the style of the prose and

the format and design of the report.

Although format and design specifics can vary from organization to organization within

the field of chemical engineering, this manual guides you through the specifics of formatting,

structuring, writing, and editing your lab reports for this course. It also offers some handy tips

for improving the overall quality of your prose.

Audience & Lab Reports (generally)

In telling any story, what you tell, as well as how much context and detail you include,

depends on who the listener is. For example, if you ask a friend to meet you at Tech Tower

before a football game, you do not have to describe what Tech Tower looks like and where it is if

your friend is a Tech student, but if he or she isn’t, you would need to include more detail and

direction. In writing your lab report, you need to consider such issues. Who would read a lab

report? Why? And how much do they already know about the subject?

In general, people would read a report such as the ones you will write because they may

find it necessary to undertake a similar study OR they may want to use your findings to help

make design or purchase decisions. Given this information, you can assume that your readers


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have a basic understanding of general chemical engineering principles — for example, fluid,

mass, and heat transfer; thermodynamics; reactor design; process control; and so on. In short,

any individual with an average knowledge of chemical engineering concepts should be able to

read and understand your report without difficulty (Imagine a ChBE or other engineering

graduate or an MBA working in a ChBE industry). However, you should recall that even a

qualified chemical engineer may have forgotten the specifics of some area of this field. Thus,

you may need to remind them of some of the details or clarify the operation of specific units.

Rhetorical Context for ChBE 4200/4210 (your specific audience & purpose)

What is rhetorical context? It is simply the situation that surrounds your act of writing.

What are you writing? Why? For the purposes of this course, you are not a student when you

write your lab reports. Instead, you are to assume that you are an engineer working for a

company that has just purchased several experimental set-ups. Each set-up was designed to

measure the physical or chemical properties of a system or characterize a unit operation, reaction

process, or transport process. A manual of suggested experiments was provided. Your boss has

asked you to work in a team of three (or two) to evaluate the performance of each set-up by

conducting an experimental study in each over a range of specified conditions. You are then to

report back on the behavior of the system studied and analyze and characterize the phenomena as

directed by the lab manual. You should also convey the “bottom line,” or overall conclusion,

reached from your experiment(s), as well as one or two relevant recommendations.


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Format, Font, and Word Limi ts

FORMAT: Two columns, justified, 1.5 line spacing, Page numbers at bottom center

FONT:Main text: 11 or 12 pt Times New Roman fontTable titles and figure captions: 10 pt Times New Roman

SECTIONS WORD LIMIT

( No title page — just put title page info at top of the first page — see the first Lab Report Example in the Style Guide for details.)( No table of contents)Abstract 275 words

Introduction 170 words

Theory 275 words

Apparatus and Procedure 150 words

Results & Discussion 550 words (no more than 4 tables or figures in R&D)Conclusions & Recommendations 160 words

(combined)References At least THREE outside references (not including Safety Data

Sheets [SDS] or lab manual) are required. Two-column formatrequired.

Nomenclature Nomenclature does not have to be in 2-column formatAppendix A: Title of Appendix Appendices do not have to be in 2-column formatAppendix B: Title of Appendix

(other appendices as needed)

Note: Word limits do NOT include table titles or figure captions.


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Abstract

The Abstract is a focused summary of the report; it provides readers with a glimpse of the entire

report in a shortened form. In this, it is one of the most important parts. It helps a reader decide

whether to read, skim, or skip the document or to pass it along to others. To accomplish these

goals, the abstract must answer these questions:

- What was done, and why? ( should include one introductory sentence putting the

experiment and its field in perspective, thus motivating the study; a brief description

of apparatus; statement of objective(s); and a brief description of methods, including

range of conditions if appropriate)

- What were the results, and what conclusions were drawn from them? (includes

significant results with some level of quantification, comparison to theory/model

expectations, error analysis, and key conclusions)

Abstracts are typically single-paragraph discussions, and they stand completely alone.

This means they would be understandable even if published by themselves, as they often are in

databases of abstracts. Given this constraint, the abstract never specifically refers to any figure

or item in the report, but contains its own independent quantification of the results.

The first part of the abstract provides motivation for the study and gives the experimental

objectives as well as a brief overview of the apparatus and procedure. It should also mention any

critically important issues, such as any difficulties that prevented meaningful interpretation of

some of the results. The abstract should begin with an orienting sentence (one that provides

some perspective on the significance or motivation behind the work). This sentence should be

informative: a good opener clearly explains significance and motivates the study. Generic

sentences such as “Packed-bed absorption is important in chemical engineering” should be

avoided. A more effective example would give a specific feature or benefit that explains WHY

packed-bed absorption is important in a particular field or process. See sample reports for

examples.The second, and most important, part of the abstract discusses the results and conclusions

of the experiments. Appropriate levels of quantification vary depending on the experiment. For

example, if the goal of the lab was to determine one or two quantities, then these may be placed

in the abstract with their statistical confidence intervals. If several experiments are performed, a


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general description of the observed trends in the data or of how the results compared to a model

or theory should be included. However, even this general description can be quantitative.

For example, phrases like “…the data were similar to the model.” should be avoided in place of

more quantitative phrases such as “… all data points were within 5% of the model predictions.”

or “…the root mean square average of the difference between the data points and the same points

predicted by the model was 7.4%.”. Finally, the abstract should end with one or two key

conclusions that indicate what was learned from the experiment and give the “bottom line.”

Generally, recommendations do not belong in the abstract.

* * Whi le thi s section provides a summary of the enti re report, i t cannot exceed 275 words.

Therefore, you must spend your words wisely and make sur e each one counts. Be sur e to

answer WHAT, WHY, HOW, and SO WHAT?. See abstracts in the Lab Report Examples or

in technical journals for examples.

Below is a good example of an abstract. (This example has 275 words.)

Abstract

A fin is a surface that extends from an object, creating additional surface area that

promotes heat transfer. One common application is in gas turbine engines, which often use pin

fin channels for internal cooling. In this experiment, three cylindrical pin fins were studied: two

aluminum fins of varying diameters and a stainless steel fin. The objective was to determine the

effects of fin geometry and composition on the heat transfer from the fin to its surroundings. A

mathematical model, based on Fourier’s law and energy balances, was evaluated by determining

the heat-transfer coefficient (h) of the two aluminum fins as well as the thermal conductivity (k)

of the stainless steel fin. The objective was accomplished by taking temperature readings as a

function of distance from a heat source. The convective heat transfer coefficients of the ½ in.

aluminum fin and the 1 in. aluminum fin were determined to be 13.43 2w

m k and 9.410 2w

m k ,


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respectively, indicating h is inversely proportional to D. Using these h values, the k of the

stainless steel fin was calculated to be 16.79 mk

w

, which differed by 11.2% from the k value

reported in the literature for stainless steel. The 1 in. diameter aluminum fin transferred four

times more heat to the surroundings than the ½ in. diameter aluminum fin, indicating that greater

surface area increases heat transfer. Thermal conductivity of a material was also proportional to

the amount of heat transferred. Since the results generally agreed with expectations based on

theory, we concluded that Fourier’s law and energy balances accurately describe fins. The

11.2% error in calculation of thermal conductivity can be attributed to the assumption of

indefinitely long fins.

Note: you should use SI units throughout the whole report.


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distillation is very important in separating chemical substances” is generic because the term

“Fractional distillation” can be replaced by a variety of unit operations.

In the second paragraph, you need to:

o briefly describe the key physical and chemical characteristics of the

operation, focusing on those that are particularly relevant to your analysis;

o state your objective(s) clearly and thoroughly; and

o briefly indicate how you met those objectives.

If you used your first paragraph to lead subtly up to your objectives, this next paragraph should

come as no surprise to the reader. Make the wording of your objective as specific as

possible — and remember that a good objective must be measurable. (Hint: “the objective

was to characterize/study/observe the performance of [xxx apparatus]” is neither specific nor

measurable). Beware of copying the objective as stated in the lab manual — in most cases this isa general goal, and it is your job to whittle it down to a specific, measurable objective. You also

need to provide one or two sentences to very briefly describe the methods used to meet your

objective(s). You should NOT present any results in this section.

** Information in this section should be organized from general => specific, like an inverted

triangle. This section should be no more than 170 words long.

**The purpose of the Intro is to give perspective and background on why the objectives and the

study are important. In other words, it needs to motivate the study.

Below is a good example of an introduction.

Introduction (word count = 170)

In the chemical industry, distillation is often used to separate species with different

relative volatilities. However, when two liquid species have similar volatilities, distillation is not

feasible; instead, liquid-liquid extraction (LLE) can be used for separation. LLE relies on

differing solubilities for separation1 and is particularly useful to separate petroleum products that

have different structures but similar volatilities.2 One limitation of LLE is that the columns

require a large number of stages to achieve an effective separation.3


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The objective of this experiment was to investigate the effect of oscillation rate of a Karr

plate column on the separation of propionic acid from diesel fuel. Water was a suitable solvent to

use because the acid exited in the water stream, leaving the kerosene acid-free. To achieve the

objective, the column was run at four different oscillation rates. At each rate, the extract and

raffinate streams were titrated to determine acid concentration. These data were used to

determine the percentage of acid transferred to the water. Experimental results were then

compared to published correlations.


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Theory

The Theory section presents the models (usually one or more equation/s) used to analyze

your experimental data. The purpose of this section is to lay out an interpretive model; it tells

your reader what theories and equations are important to interpret data from the experiment

(specifically, what theories and equations are being used). When you write this section, be sure

to move logically from one equation to the next — use transitional words and phrases.

Here are some key guidelines to follow in the theory section:

Because this section is devoted to theory, it is written in the PRESENT TENSE.

You should also avoid using the general “we” in this section, in the sense of

“we need to examine,” “Here, we can see,” and so forth.

As with the introduction and abstract, economy of prose dictates that obvious or

generic sentences should be avoided. Sentences like “In order to understand

reactive distillation, one must first understand the theory behind reactive

distillation” are generic and do not add value to the section.

Avoid repeating much of what is in the laboratory manual. Simply include

the important final equations, along with a clear yet concise explanation of the

main theory or model being used and any important assumptions or limitations.

Any additional equations that are needed should be detailed in an

appendix — be sure to reference (“call out”) this appendix in your main Theory

section.

If an equation only has a few terms, you can define them in the Theory section as well as

in the Nomenclature section. However, if your equation has more than three or four terms, you

might not have room to define them all in the Theory section. In this case, simply refer the reader

to the Nomenclature section for definition of all terms in the equations. Either way, you will

always need to have a Nomenclature section in each lab report.


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To achieve its purpose, the Theory section needs to

briefly clarify engineering concepts and show the development of the model include all assumptions, previous work that supports the model, and any limitations if they

are known.

cite sources (including the lab manual) for all equations.

The Theory section should NOT be a carbon copy of the lab manual. Your goal is toshow an understanding of the theory or model, not just to copy a bunch of equations.

The word limit for the Theory section is 275 words.

As for each section in the lab, this section should begin with a sentence that lends perspective

to the Theory section relative to the lab report as a whole. This opening matter should be as

specific and informative as possible. Do NOT use generic statements such as “In order to

understand this lab, it is necessary to understand the theory behind it.”

Here is an example of a good opening passage for the Theory section:

Many processes that involve phase changes, such as evaporative cooling, are governed

by the balance between the heat loss due to evaporation and the convective heating caused by

the evaporative cooling. This experiment studies this balance in the evaporative cooling of water

on a copper cylinder. The energy balance for such a process is written as…..

Final note: If you took any equations from the lab manual or any other source, be sure to

include an in-text citation and a corresponding entry in your References. Failure to do so may

constitute plagiarism.

THEORY – (good example — about 268 words)

The steady-state temperature of the gauze-covered copper cylinder is governed by the

balance of evaporative cooling and convective heating. This energy balance is written as


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vair

xair H x

x-x Ak -T T hA

dt

dT C M ˆ

1

(1)

The term on the left-hand side is the net energy accumulation of the system, and the left and right

terms on the right-hand side are the convective heating and evaporative cooling, respectively.

The specific terms in all equations are defined in the Nomenclature section.

Assuming that the heat capacity of gauze is equal to that of water, all parameters are

constant with temperature, the interfacial mole fraction of water is at its equilibrium value, and

the temperature variations in the rod are negligible, Equation 1 is integrated to obtain the transient

energy balance, Equation 2:

t C D

h

T T

T T

ccciair

air

4ln

(2)

The value of h determined from Equation 2 is then used to estimate the mass transfer coefficient

by invoking the Chilton – Colburn analogy between heat and mass transfer.3

Once the heat and mass transfer coefficients are determined, the other constants in

Equation 2 are determined by direct measurement or obtained from the literature. Finding theseconstants allows Equation 1 to be numerically integrated to obtain a model of the transient mass

and energy transfer. Raoult’s law and the Antoine equation for vapor pressure are used to

determine this equilibrium value of the water fraction at the interface.

Finally, the steady-state value from this model is obtained by setting the left-hand side of

Equation 1 to zero. This steady-state temperature should be comparable to the wet bulb

temperature, which can be determined from a psychometric chart for the conditions of

temperature and humidity in the surrounding air.


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Experimental Apparatus and Procedure

This section describes the apparatus you used to conduct the experiment and explains

how you used the equipment to do the experiment. This section can be broken down into two

main paragraphs: description of apparatus, and description of procedure and key safety issues.Please note: The entire Apparatus and Procedure section should not exceed 150 words. You

should use SI units through the whole report.

Paragraph 1:

Description of the apparatus. Give a BRIEF, general description, no more than one short

paragraph in length.

Verb Tense for Apparatus Description:

Description of apparatus can be in either PRESENT or PAST tense, depending on

the context.

Example of apparatus description: (92 words)

In this experiment, we used a countercurrent Karr column with reciprocating sieve plates.

The column was 1 in. in diameter and 6 ft in length, and each end of the column had a 2-in.

diameter disengagement section. The water and diesel were pumped from storage tanks through

calibrated flowmeters. A needle valve was used to maintain a constant interface between the

organic and aqueous phases. The extract flowed from the bottom of the column while the

raffinate flowed from the top of the column. Figure 2A in Appendix A details the apparatus.

Note: You must include a clearly labeled schematic diagram of the apparatus (or therelevant portion thereof) in this section, or in the appendix (but you need to call out theappendix). You may use a photo of the lab equipment to supplement, but not replace, thediagram! Be sure to include a citation for the picture or diagram, even if it is from the labmanual.

Paragraph 2: References the procedure and describes key safety issues.

This paragraph should begin with some version of this sentence: The experimental

procedure was taken from the UO Lab Manual1 and followed without any deviations / followed

with the exception of several deviations. Be sure to reference the lab manual. If there were any


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significant deviations, those should be described next. You should also include any key variables

not specified in the lab manual, such as the experimental conditions used, flow rates, space time,

and so on. Finally, any relevant safety issues should be briefly discussed, and you should cite the

SDS for any chemicals you used in the experiment. You also must include a sentence

referencing standard safety protocol — see the example below. (NOTE: the SDS references do

not count towards the requirement for three outside references!)

Verb Tense for Procedure Description:

Procedure description should be mainly past tense, with the possibility of present

tense when discussing chemical hazards, etc.

Experimental Apparatus and Procedure (good example)

(Note: the main goal was to investigate a process of mass and convective heat transfer occurring simultaneously)

The equipment for the simultaneous heat and mass transfer experiment consisted of a

stand outfitted with a clamp placed in front of a small wind tunnel. Other equipment included a

bare copper cylinder, a gauze-wrapped copper cylinder with a smaller diameter, a thermocouple,

a stopwatch, an ice water bath, and a room-temperature water bath. The copper cylinders had

small holes in the end where the probe of the thermocouple was placed. The experimentalapparatus is shown in Figure 1.

[Figure 1. Diagram of apparatus goes here, or in an appendix (must call out the appendix).

Remember to include citation at the end of the caption if taken from an outside source, including

the lab manual!]

To meet the experimental objective, we followed the procedure as outlined in the UO Lab

Manual1 but with several deviations:

(describe first deviation)

(describe second deviation)


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(etc., etc.)

This experiment presented no significant safety hazards, and no chemicals were used. Standard

safety protocol, including the use of safety glasses, closed-toe shoes, lab coats, and gloves, was

followed.

Note: For a lab in which chemicals are used, the safety paragraph should follow the basic

structure below:

The main safety concerns in this experiment were that sodium hydroxide is a strong base and is

corrosive, and ethyl acetate is flammable.2 For other potential chemical hazards, refer to the

safety data sheets (SDS) listed in the References section.3,4 Standard safety protocol, including

the use of safety glasses, closed-toe shoes, lab coats, and gloves, was followed.


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Resul ts and Discussion

The purpose of this section is to convey what you found in doing the experiment and to

explain the significance of those findings. This section also compares the results you obtained

with those you expected (per theory or literature). It also explains error — it should discuss the

source of errors and should also quantify and characterize their impact on the experiment. To

reach these goals, this section needs to:

present and explain your results in a clear, well-organized, and concise manner

(use figures and tables to present information efficiently; make sure that you

provide all results that are requested in the lab manual, as well as any others that

you feel are appropriate and relevant); and

discuss and analyze the significance of those results, including how they relate

and compare to your theory/model, sources of error, and the effect those errors

had on the experimental results.

Organizing information in the Results and Discussion section can be tricky. Generally,

you begin by briefly summarizing your overall goal (or the first part of it) and briefly reviewing

the first step of the experiment. Then, you may wish to present a figure or table of the raw data

(or a typical subset) to convey information about scatter, the range over which data were taken,magnitudes, and so on. However, please avoid large tables with tons of data — these are best

placed in the appendix, not here. Then, you break this information into its significant component

parts and focus on each part individually. Your discussion/analysis should occur at the same

time. The section may conclude with some discussion of err or to clarify the “big picture”

(although it often makes more sense to discuss error as you go along). For example, if you find

that your results generally are not what you expected — or are not ideal — you must discuss the

discrepancies. What could account for them? What caused you to suspect these sources? How

exactly did these discrepancies affect your results? Provide evidence to support your claims,

quantify the impact of various sources of error, and characterize the impact of any erroneous

assumptions.


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In working through each part of your data, each figure or table must be briefly introduced

before the reader sees it (e.g., “Table II shows the relationship between time and temperature.”).

After presenting the figure or table, it must then be explained--point out significant features or

trends; tell your readers what you want them to see in the figure or table (e.g., “Figur e 4 shows

that as time increased, temperature decreased.”) and discuss the trends that are shown. If you fit

your curve to a specific subset of your data points, explain your reasoning. Also, indicate your

reasoning behind any corrected data.

You are limited to no more than FOUR tables and figures (total) in the Results &

Discussion section. We do want you to use tables and figures (usually, you should have at least

two in this section), but we don’t want you to go overboard in such a short report. The trick is to

decide which tables and figures do the best job of illustrating the key points you wish to convey.All other relevant tables and figures may be placed in an appendix and called out in the main

text.

Finally, you need to discuss the importance of your findings — both generally AND in

relation to your theory or model (e.g., “The reciprocal relationship between time and temperature

reveals . . .This relationship between time and temperature was expected based on…. It shows .

. .”). Be sure to discuss any specific error and the effect that such error might have had on the

particular part of the data on which you are focusing. Quantifying the impact of error on your

results is quite helpful to the reader as well.

Use significant figures in all of your results (to review the conventions of significant

figures, see Felder and Rousseau, 2000). You should know how precise your data are; the

significant figures must reflect the precision of the data. Also, in reporting the average of

repeated data, include the confidence interval, and where possible apply propagation of error

analysis. You should use SI units through the whole report.

Note: Before you can write the Results and Discussion section, you must complete the sample

calculations (include in an appendix). You will need to mention any data that were rejected in

the calculations and any data that may be erroneous. However, you do not want to inundate

readers with numbers and figures; rather, escort them carefully through the logic of the


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calculations. It is much easier to grade a report that presents sample calculations clearly,

thoroughly, and logically.

Here are examples of opening sentences for the Results and Discussion section:

To determine the effect of horsepower on the performance of the laboratory pump, thefirst step was…

The first experimental objective was to calculate the oxygen permeance and

oxygen/nitrogen selectivity of the membrane; to meet this objective, …

Again, the general format of this section is as follows:

1 - To determine ……, we measured / calculated / etc. …

2 - Figure 1 below illustrates the relationship between….

3 - [Insert Figure 1]

4 - As Figure 1 shows,…

5 - These results suggest/indicate that…

6- The results were expected per theory/model, OR, the results were unexpected, and

here’s what we think caused the discrepancy

You will follow this general format for each result you present.

Again, you should thoroughly analyze and explain your results, possible sources of error,

the degree of confidence, and the implication of your observations. Even if your results are poor,if you can explain them well and account for discrepancies, you can still get a good grade.

Conversely, good results, particularly if presented poorly, do not guarantee a good grade.

Transitions

The skillful use of transitional words, phrases, and sentences will make the difference

between a report that is easy to follow and a report that is not. Thus, you should try to lead your

reader through the discussion of results with sentences like “After determining that flow rate

increased with….., we next analyzed the relationship between…”…. For example:

Once the heat transfer coefficient was calculated, the next step in creating a model forthe simultaneous heat and mass transfer cooling of a copper rod was to determine the mass-transfer coefficient. This determination was accomplished by…..


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Determining the mass transfer coefficient provided the data necessary to formulate amodel of the cooling process seen in Figure 3. To derive the model, …

After deriving the model, we then compared the model with our experimental data.Figure 5 shows this comparison.

** These transitions make reading through the analysis and discussion of the results mucheasier. They are like road signs telling you where you’ve been, where you are , and where you’re

going, and how the individual results are related to and build upon each other.

**See Appendix F: Transitional Words and Phrases for examples of transitions.

The length of the Results and Discussion section will vary per experiment (aim for around 450-550 words). It should be the longest and richest section of the report.

In Results & Discussion, you should keep procedural and calculation details to a minimum as

much as possible. The main focus should be on your results and what they mean — spending

more time on the most important results. You can also use appendices to explain how you

calculated certain values — just be sure to “call out” the appendix in the main body of the report.

Please see Lab Report Examples for good examples of Results & Discussion.


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Conclusions & Recommendations

The Conclusions & Recommendations section presents a final assessment of the

experiment and results. The purpose of this section is to give your reader a final, broader sense

of the experiment and its success or problems. Here, you are presenting “bottom-line”conclusions that are supported by your results and analysis. Ultimately, how well did the

experiment perform? Did the results compare well with expected or ideal results? How reliable

were your data? In this section, keep your rhetorical context in mind. What would you want to

tell your boss about this particular experimental set-up? Is it a good one? Should it be returned?

Will it save the company time or money? Remember, the goal here is to state conclusions

based on your key results and to provide a broader context, NOT to simply repeat your

results! No brand new results should be presented in this section. In other words, don’t “save”

results for this section, and don’t bring ideas up out of the blue.

The final sentence of your Conclusions paragraph should address the “big picture”— it should

answer the question “so what?” about your results. Why would these results be relevant or

applicable to industry? This “overall conclusion” is something that could also appear in your

abstract, but would not be mentioned explicitly in any other section. It should, however, flow

naturally from the results that you obtained. You may also try to link this “overall conclusion” to

the motivation that you brought up in the Introduction, thus “closing the circle.”

You should also include two or three relevant recommendations in this section. These may offer

relevant, non-generic suggestions for improving the experimental set-up or procedure, as well as

suggesting what the next stage of experimentation might be. For example, statements like “we

recommend XX repetitions of the entire experiment XX for greater statistical accuracy” are too

generic and therefore not suitable as recommendations. On the other hand, it is appropriate to

identify specific aspects of the experiments where improvements would be particularly beneficial

(e.g., “Use of a digital thermometer with more accurate temperature readings in the outlet

stream of the heat exchanger would enable more precise determination of the heat transfer

coefficient.”).


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For example:

This experiment was successful in showing that efficiency of a laboratory centrifugal

pump was directly related to…. We discovered that…..The data demonstrated internal

consistency since…….. Furthermore, the data were shown to be accurate based

on……However, a calibration error caused…..Overall, the experiment indicated that this pump

would / would not be useful in an industrial process with ….requirements.

For the future, we recommend improving this experiment by…..An additional

recommendation to reduce error is to….

** What did you find? What did you learn? What are the sources of error? Degree of

confidence? What are the implications of your observations? What’s your OVERALL

conclusion? Don’t forget to provide evidence (quanti tative, if possible) for your claims

** In this section, you should draw conclusions based on key resul ts . What did you learn from

this experiment and, more specifically, these results regarding this process / mechanism?

*Aim for around 160 words for your Conclusions & Recommendations section.

Below is a good example of a Conclusions & Recommendations section.

Conclusions & Recommendations (about 160 words)

In this experiment, the effect of oscillation rate on the separation of propionic acid and

diesel through liquid-liquid extraction was successfully determined. The percent of propionic

acid removed increased with increasing plate oscillation rate, despite discrepancies in the mass

balance equations. Increases in the oscillation rates also correlated directly with the number of

equilibrium stages. Additionally, as the oscillation rate increased, the HETP and H0y values

decreased. However, experimental trends did not agree with published correlations because of

differences in operating conditions. Overall, results indicated that higher oscillation rates in an

industrial LLE process would increase mass transfer.


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Recommendations for this lab include allowing longer trial durations to ensure steady

state operation is maintained, as well as performing the experiment at higher oscillation rates to

determine an optimal rate for mass transfer efficiency. Additionally, a device that could

mechanically count and report the oscillation rate of the column would greatly reduce the human

error involved in counting items moving at such a great velocity.

Brief note about recommendations: * * Be careful of “whining” or sounding too

student-y (remember your rhetorical situation). You should not complain about the TA, or about

directions in the lab manual or problems you had doing the experiment because of the directions,

or about the experiment taking too long. Instead, offer your colleagues recommendations for

doing the experiment more efficiently or safely so as to achieve more accurate or conclusive

results. You can also suggest other methods of experimentation or analysis for the future, as

long as you tell us why you’re making the suggestion. As always, avoid generic and vague

statements.


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References

Because good research is a key part of any report, it is required that you include at least THREE

outside references in your report (i.e., references other than the lab manual and SDS). The SDS

websites should be cited in the Procedure section and included as references in your References

section, but they do NOT count towards this requirement. These outside references may include

textbooks, journal articles, books, online scholarly articles, academic websites, and so on. Just

make sure that you cite them properly, both within the text and in the References section. Citing

Wikipedia or About.com (or other such encyclopedic, non-peer-reviewed sites) is NOT

permitted. However, Wikipedia can be an excellent starting point in finding more credible

sources.

In this class, we will follow the ACS Reference style as explained in detail in The ACS

Style Guide (3rd

edition). In organizing the information in the References section, please use the

following “templates” to organize and punctuate the standard bibliographic information. If some

standard information is not available (e.g., an author), you should omit that category (see

examples under “Article in an anthology,” which has no author , and “On-line Article or Web

Site,” which has no author).

Note that each reference entry should end with a period.

Number your entries in the order in which they are first cited in the text.

The entire list of references should be in two-column format, and should have 1.5 line spacing

(see examples below).

For a book written or edited by one or more persons:

First author’s last name, first and middle initials; second author’s last name, first and middle

initials; etc. Title of Book, ed number .; Editor 1, Editor 2, Eds. (if an edited book); Publisher:

Place of Publication, Year; Page number(s) used.

EX.Coulson, J.M.; Richardson, J.F. Chemical Engineering , 4th ed.; Elsevier: Oxford, 2005; p 34.

http://pubs.acs.org/doi/abs/10.1021/bk-2006-STYG.ch014http://pubs.acs.org/doi/abs/10.1021/bk-2006-STYG.ch014http://pubs.acs.org/doi/abs/10.1021/bk-2006-STYG.ch014http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/isbn/9780841239999http://pubs.acs.org/doi/abs/10.1021/bk-2006-STYG.ch014


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OR (for multiple pages):

Coulson, J.M.; Richardson, J.F. Chemical Engineering , 4th ed.; Elsevier: Oxford, 2005; pp 1; 7;34.

OR (for a page range):

Coulson, J.M.; Richardson, J.F. Chemical Engineering , 4th ed.; Elsevier: Oxford, 2005; pp 34-40.

NOTE: if authored by more than one person, list names in the order in which the names appear

on the book’s title page. Names of authors and editors should be listed as last name, first and

middle initials (skip the middle initial if not provided). Authors’ names are separated by a semi-

colon. Editors’ names are separated by commas. Be sure to include each author or editor, even if

there are more than three. For an article in an anthology/book ( note that the UO lab manual is considered to be an

anthology):

Author’s last name, first and middle initials. Title of Article. In Title of Book , edition number (if

there is one); Publishing company: Place of publication, Year; Volume number, page number(s).

EX.Continuous Stirred-Tank Reactors. In Unit Operations Lab Manual ; Georgia Tech: Atlanta, GA,

2016; p 4.

Continuous Stirred-Tank Reactors. In Unit Operations Lab Manual ; Georgia Tech: Atlanta, GA,

2016; pp 4-6.

*Note that in the above examples, no author was listed for the article; therefore, this part of the

entry is omitted. Any time you cite the lab manual, you omit the author’s name.

For an article in a journal:

First author’s last name, first initial and middle initial; second author’s last name, first and

middle initials; etc. Title of Article. Journal Title (or Abbreviation) Year , Volume (Issue number

or Month and date) , Inclusive Pagination.


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(The journal title should be italicized and may contain approved library abbreviations. When in

doubt, use the full journal title. The year should be in bold. The volume number should be in

italics.)

EX.Taveira, P.; Cruz, P.; Mendes, A. A Maxwell-Stefan Experiment. Chem. Eng. Educ. 2000

34 (1), 90-93.

For a general web site:(although your source may not offer all of the following, include as much as possible.)


initials; etc. Title of Article/Document. Title of Site. URL (accessed Month, Day, Year), other

identifying information, if any.

For title of site, use the title found on the Web site itself. Add the words “Home Page” for

clarification when needed.

EX.Smith, J.S; Floating Point Unit Operations. MIPS Technologies, Inc.

http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi/ hdwr/bks/SGI_Developer/books/

R10K_UM/sgi_html/t5.Ver.2.0.book_313.html (accessed June 10, 2016).

For a document retrieved from an agency or university web site:


initials; etc. Title of Document, Year. Title of Site. URL (accessed Month, Day, Year), other

identifying information, if any.

If an article is contained within a large and complex Web site, such as that for a university orgovernment agency, the host organization and the relevant program or department should be

identified BEFORE giving the URL and access date.


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EX.

Technology integration and publishing, 2001. Columbia University for Learning Technologies.

http://www.ilt.columbia.edu/tech-and-pub-past-projects/ (accessed June 10, 2016).

For PowerPoint slides or handouts from a class or presentation:

Presenter ’s last name, first and middle initials. Title of Presentation. Presented in

Course/Conference Title, Place, Date.

EX.

Henderson, C. Statistical Modeling. Presented in ChBE 2120, Georgia Tech, May 25, 2014.

Jones, J.M. Developments in Transdermal Drug Delivery. Presented at the 10th International

Conference on Drug Delivery, Montreal, Canada, June 12, 2012.

For your own lecture notes from a course:

Instructor’s last name, first initial. Course title lecture. Place, Date.

EX:Breedveld, V. ChBE 3200 lecture. Georgia Tech, May 15, 2013.

In-text Citations

For information on citing material within the text, please see Appendix B of the Style Guide.


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Sample References section

Number your references in the order

in which they are first cited in the text.

Please use 1.5 line spacing.

1. Taveira, P.; Cruz, P.; Mendes, A. A

Maxwell-Stefan Experiment. Chem.

Eng. Educ. 2000 34 (1), 90-93.

2. Geankoplis, C.J. Transport Processes

and Unit Operations, 3rd ed.; PTR

Prentice Hall: Princeton, NJ, 2003; pp

27-30.

3. Continuous Stirred-Tank Reactors. In

Unit Operations Lab Manual ; Georgia

Tech: Atlanta, GA, 2016; p 4.

4. Floating Point Unit Operations. MIPS

Technologies, Inc.

http://techpubs.sgi.com/library/tpl/cgi-

bin/getdoc.cgi/hdwr/bks/SGI_Developer

/books/R10K_UM/sgi_html/t5.Ver.2.0.b

ook_313.html (accessed June 4, 2016).

5. Felder, R.; Rousseau, R.W. Elementary

Principles of Chemical Processes, 3rd

ed.; John Wiley & Sons: New York,

2000; pp 4, 21.


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Nomenclature

The Nomenclature section provides a “key” to the symbols and units used in the lab report.

Please note that SI units should be used here, as well as throughout the report.

Items should be listed in alphabetical order, putting all English symbols first, then Greek.

Note: EVERY report MUST have a Nomenclature section (even the Gummy Bear report!)

The Nomenclature section does not need to be written in 2-column format.

Sample Nomenclature

Symbol Definition Units

A surface area m2

C pair heat capacity of air J/kg/K

C pc heat capacity of copper J/kg/K

C pw heat capacity of water J/kg/K

DAB diffusivity of an air water system m2/s

Eacc energy accumulated in a system J

Eg energy generated in a system J

Ein energy entering a system J

Eout energy leaving a system Jh convective heat transfer coefficient W/K/m2

Hfg mole heat of vaporization of water J/kg

Jix molal flux relative to molal average velocity -

K air thermal conductivity of air W/K/m2

K c thermal conductivity of copper W/K/m2

K w thermal conductivity of water W/K/m2

Lc Length of copper cylinder m

M molecular weight g/mol

N pr Prandtl number -

Nsc Schmidt number -

Nw molal flux of water relative to stationary coordinates J/m2/s


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P atmospheric pressure mmHg

pw partial pressure of water mmHg

Pw vapor pressure of water mmHg

T temperature of cylinder at time t oC

TAir air temperatureoC

Tdb dry bulb temperatureoC

T1 initial temperature of copperoC

U molal average velocity -

V volume m2

x mole fraction of water vapor at surface of gauze -

xAir mole fraction of water vapor in room air -

yAir mole fraction of air -ρc density of copper kg/m

3

ρw density of water kg/m3

μair viscosity of air kg/m/s

μw viscosity of water kg/m/s

Δx characteristic length m

Δxw concentration gradient -


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Appendices

The Appendices include the following:

Complete sample calculations with tables of intermediate results. Since only the finalcalculations are included in the body of the report, the intermediate and samplecalculations must be detailed enough for the grader to check for errors . They must beadequately introduced and explained by text so that the grader can easily understand them.Equations should be referenced to the Theory section or literature. Physical and chemical properties used in the calculations should be referenced to literature. Units should always beincluded and conversions shown. The calculations may be neatly handwritten in ink .You must cite every source from which equations/literature data were drawn.Appendices do NOT need to be written in 2-column format.

NOTE: Even if spreadsheet calculations are attached, you must include

handwritten sample calculations to show how each column/row of the spreadsheetwas obtained. Be sure to define each column and row of the spreadsheet, as wellas the units.

Sample Calculation Rules:

a. Arrange them in a logical order. b. Define all terms.c. Show all units/unit balances and conversions.d. Lead the reader through the work by putting a sentence or two preceding each

calculation explaining what is being done. Work that is easily understood ismore easily graded.

e. Use one set of conditions, wherever possible, to show the logical progression

of the calculations.f. Any equation used from the Theory section of the lab manual must be cited.g. Any data from the literature must be cited.h. Any data table generated by computer calculations must be briefly explained.i. Numerical values should have the correct number of significant digits (less

than 4) even for the spreadsheet calculations.

A photocopy or scan of your original data sheet(s), signed by either the TA or the labcoordinator, is to be included as an appendix (called Raw Data) in your lab report. Nochanges should be made to the original data sheet once the lab session is complete.

Any other pertinent information that does not belong in the body of the report (such as long

derivations or supplemental figures and tables) can be included as an appendix. Each appendix should start on a NEW page.


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Lab Report Examples

What follows are two examples you may use when developing your lab report. Note that these

are not perfect examples; their purpose is to provide general guidelines as to the proper

organization and style of a lab report.


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33

CHBE 4200 – Unit OperationsDr. Yonathan Thio – Ms. Jacqueline Snedeker

Lab 5: Liquid-Liquid ExtractionGroup 1: Hillary Clinton, *John Kerry, and Donald Trump

Date Performed: June 7, 2016 – Date Submitted: June 13, 2016

ABSTRACT

Liquid-liquid extraction (LLE) is

important in separations where distillation is

unfeasible due to low volatility differences.

The objective of this experiment was to

investigate the performance of a Karr

reciprocating plate extraction column for

separating propionic acid from diesel using

water as a solvent. This objective was

achieved by performing mass balances and

exploring the effects of plate oscillation rate

on mass transfer efficiency. A 0.02 M

solution of NaOH was used to titrate the

extract and raffinate at three different

frequencies (144, 174, and 210 min-1) to

obtain the fraction of propionic acid in each

stream. The percent of propionic acid

removed through the extract was calculated

for each frequency as 71.9, 73.0, and 79.4%

for 144, 174, and 210 min-1, respectively.

This increasing trend was due to higher

oscillation rates that generated more surface

area for mass transfer. The number of

equilibrium stages (N) was then calculated

using the Kremser equation as 0.569, 0.659,

and 0.908 for 144, 174, and 210 min-1,

respectively, indicating higher oscillation

rates resulted in a better separation. Based

on these N values, the height equivalent to a

transfer plate (HETP) values were calculated

as 321, 278, and 201 cm, for 144, 174, and

210 min-1, respectively. When these

numbers were compared to HETP values

from Bensalem and Tawfik correlations, a

significant amount of discrepancy was

evident. This error can be attributed to the

correlations being derived from systemscomposed of different compounds than

those used in this experiment. Finally, the

mass transfer coefficients were found to

increase with increasing oscillation rate.

These results again showed improved mass

transfer efficiency with at higher oscillation

rates.

INTRODUCTIONLiquid-liquid extraction (LLE) is an

important method for separating compounds

of similar volatility and boiling points that is

commonly used in the production of

petroleum and organic solvents.

Additionally, no phase change occurs during

LLE, making it preferable when a mixture’s

components are temperature sensitive.


characterize and investigate the performance

of a Karr reciprocating plate extraction

column for separating propionic acid from

diesel using water as a solvent. This


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34

objective was achieved by performing mass

balances and exploring the effects of plate

oscillation rate on mass transfer efficiency.

Flow and composition samples were taken

from the raffinate and extract under the

varying oscillation rates. Each sample was

then titrated to yield the degree of separation

achieved, which allowed height equivalent

to a transfer plate (HETP) to be calculated.

These values along with height of an overall

raffinate transfer unit values allowed the

relative mass transfer efficiency to be

calculated for each trial.

THEORY

In this experiment, a dilute system with

low solubility between the diesel fuel and

water exists; therefore, the operating and

equilibrium lines are assumed to be linear.

This linearity allows for continuous contact

behavior.For the operation, a variation of the

Kremser equation that operates under the

assumption of linear operating and

equilibrium lines can be used to calculate

the number of stages:1

N

ln yb yb

*

ya ya*

ln yb ya

yb* ya

*

(1)

where N is the number of equilibrium

stages, and the compositions are shown in

Figure 1 below.

Figure 1. Extraction column analysis.2

The mass transfer rate between the two

fluids is determined by the absorption factor,

A:

A L

mV yb ya yb

* ya*

(2)

This equation represents a ratio of the slope

of the operating line to the slope of the

equilibrium line. If these lines are linear,then the water flow rate, L; diesel flow rate,

V; and equilibrium factor, m, are all

considered constant.1

Due to the difference between propionic

acid’s solubility in water and diesel, the

continuous contact mass transfer is

expressed in terms of an overall mass

transfer coefficient, which is based on thecompositions in the raffinate phase and the

corresponding height of a transfer unit:

Z H 0 y N 0 y (3)

where Z is the height of the column, and

0 is the height of an equivalent raffinate


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35

transfer unit.1 This height is described by

the following equation:

H 0 y

V

K ya (4)

whereV

K ya represents the height of a

transfer unit (HTU).1 K ya is the overall

mass transfer coefficient, and

N 0 y

A

A 1ln

yb ya

A 1 1

A

(5)

Substituting Equation 4 into Equation 3

yields

Z V

K ya N

0 y (6)

A correlation found by Bensalem can be

used to calculate the height equivalent to a

theoretical plate,

HETP 24.3 Af 0.81

U c0.21

U d 0.7

0.3

(7)

where A is the amplitude of the

reciprocating cycle, f is the reciprocating

frequency, Uc and Ud are the superficial

velocities of continuous or dispersed phases,

and φ is the holdup of the dispersed phase in

the column.1 A second correlation was

discovered by Tawfik, where HETP is

described as1

HETP Af 1.15 U c U d 0.235

(8)

APPARATUS & PROCEDURE

The experimental apparatus used in this

procedure consisted of a 1 in. in diameter by

6 ft long Karr reciprocating plate extraction

column with a variable speed motor, two

feed pumps, and two calibrated flowmeters.

A diagram of the apparatus is shown in

Figure 2.

Figure 2. LLE apparatus schematic.1

A 250 mL graduated cylinder and burette

were used to collect and titrate samples. The

procedure was taken from the UnitOperations Lab Manual1 and performed with

the following deviation: Three oscillation

rates were tested rather than four.

Flow rate and composition data

were used to determine the HTU and mass

transfer coefficient for each operating

condition. Diesel is combustible, so care was

taken to prevent ignition. Additionally, propionic acid and diesel are both irritants,

so direct contact with skin and eyes was

avoided.2 Standard safety protocol,

including the use of safety goggles, closed-


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36

toe shoes, lab coats, and gloves, was

employed.

RESULTS & DISCUSSION


determine how oscillation rate affected the

performance of a Karr reciprocating plate

extraction column by calculating the percent

acid removed, the number of required

equilibrium plates, and the mass transfer

coefficients. Three oscillation rates (144,

174, and 210 min-1) were observed, with

composition and flow samples from the

extract and raffinate taken at each. The

samples were titrated with NaOH to

determine the propionic acid content. The

diesel and water inlet flow rates were held

constant throughout the experiment, while

the raffinate and extract flow rates were

measured using a stop watch for three trials

(Appendix A). Table I shows the propionic

acid content in each stream.

Table I. Material Balance Closure and PercentPropionic Acid Removed.

The material balances do not equate,

as the amount in should equal the amount

out. Inaccuracies in the flowmeters and

difficulties in titrations are likely sources of

this discrepancy. This inequality may also

be due to unsteady-state operation of the

column. The percent propionic acid removed

increased with increased plate oscillation

rate. This trend was caused by higher

oscillation rates creating more surface area

for mass transfer to occur.

The number of equilibrium stages, N, for

the separation was then determined for each

trial. Titration data were used to find x b, the

fraction of the propionic acid in the extract,

and ya, the fraction of the propionic acid in

the raffinate (see Appendix A for

calculations). Resulting operating lines were plotted along with equilibrium data as

shown in Figure 3 (Appendix B contains

raw equilibrium data). Diesel typically

consists of 65% aliphatic and 35% aromatic

compounds3 with molecular weights ranging

from 140 to 165 g/mol. In this lab, diesel

was modeled in ASPEN as a mixture of 30

wt% heptane, 35 wt% octane, and 35 wt% benzene.

Figure 3. Experimental operating lines fordifferent oscillation rates and an equilibrium linefor a propionic acid-diesel system.

Freq(min-1)

Feed(g/min)

Extract(g/min)

Raff(g/min)

PercentRemoved

144 0.877 0.141 0.0546 71.9%

174 0.877 0.0162 0.00599 73.0%

210 0.877 0.0557 0.0144 79.4%


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37

By evaluating the equilibrium lines

at each xa and x b values, values for ya* and

y b* were obtained. The number of

equilibrium plates (N) was calculated for

each trial using a version of Kremser

equation. The resulting N values were 0.569,

0.660, and 0.908 for frequencies of 144,

174, and 210 min-1, respectively (Appendix

C contains calculations). The number of

equilibrium stages increases with the

increasing oscillation. This correlation arose

because higher oscillation rates result in a

better separation.The equilibrium number of stages

for each trial was then used to obtain values

for the HETP, and these values were

compared against HETP values from

different correlations (Appendix D). The

HETP values were plotted against

oscillation rate as shown in Figure 4.

Figure 4. HETP values from continuous,Bensalem, and Tawfik correlation methods.

The HETP decreases with increasing

oscillation frequency because the

equilibrium number of stages increases

while the column height remains unchanged,

resulting in a smaller transfer unit height.

The trends for the Bensalem and Tawfik

correlations correspond with theory, yet

there is a large degree of difference between

all three methods. This discrepancy could

originate because the correlations were

derived for systems that were different than

the system used in this experiment.

The heights of an overall raffinatetransfer unit, H0y, were then calculated and

used to obtain mass transfer coefficients for

each trial. N0y values were calculated and

H0y and K ya values were related using

Equation 4 (see Appendix E for these

calculations). Figure 5 shows the

relationship between the mass transfer

coefficient and oscillation rate.

Figure 5. Mass transfer coefficients plottedagainst plate oscillation rate on a log-log scale.


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38

As Figure 5 shows, there is a degree of

correlation between the mass transfer

coefficient and the plate oscillation rate, as

seen before in other parameters. These

results indicate that the mass transfer

coefficient for the separation increases with

increasing plate oscillation rate.

CONCLUSIONS &

RECOMMENDATIONS

In this experiment, the separation of

propionic acid and diesel through liquid-

liquid extraction was successfully

characterized. The percentage of propionic

acid removed was shown to increase with

increasing plate oscillation rate, despite

discrepancies in the mass balance equations.

Increases in the oscillation rates also

correlated directly with the number of

equilibrium stages. Additionally, as theoscillation rate increased, the HETP, N0y,

and H0y values decreased. Taken together,

these observations indicated that larger

oscillation rates in industry could result in

better mass transfer.

Recommendations for this lab include

allowing longer trial durations to ensure

steady-state operation is maintained as well

as performing the experiment at more

oscillation rates to increase the validity of

observed trends. Additionally, a device thatcould mechanically count and report the

oscillation rate of the column would greatly

reduce the human error involved in counting

items moving at such a great velocity.

REFERENCES (Should have two more

refs)

1. Liquid-Liquid Extraction. In Unit

Operations Lab Manual ; Georgia

Tech: Atlanta, GA, 2011; p 1-11.

2. “Chemical Information - Safety

Data Sheets

SDS),” ”, Environment Safety and

Health Online, 2010 (Observed

November 2011).

3. Ott, L., & Bruno, T. Variability of

Biodiesel Fuel and Comparison to

Petroleum-Derived Diesel Fuel:

Application of a Composition and

Enthalpy Explicit Distillation Curve

Method. Energy & Fuels, 22 (4),

2008; p 2861-2868.

http://www.ehso.com/sds.phphttp://www.ehso.com/sds.phphttp://www.ehso.com/sds.phphttp://www.ehso.com/sds.php


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39

Nomenclature


a interfacial area m2

A amplitude cmf reciprocating frequency s-1

H0y height of an overall raffinate transfer unit -

HETP height equivalent to a theoretical plate cm

K y mass transfer unit -

L extract flow rate m3/s

m equilibrium factor -

N number of trays -

Uc superficial velocity of continuous phase cm/sUd superficial velocity of dispersed phase cm/s

V raffinate flow rate m3/s

xi concentration kg/m3

ya propionic acid concentration in feed -

ya* equilibrium propionic acid concentration in feed -

y b propionic acid concentration in raffinate -

y b* equilibrium propionic acid concentration in raffinate -

yi concentration kg/m3

Z height of column cm

holdup of the dispersed phase in the column


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40

Appendix A. Experimental Data and Calculations

Table A1. Feed Properties.

Trial 1 Trial 2 Trial 3 AverageStandardDeviation

M (g) 3.975 4.0098 3.989 - -

V (mL) 5 5 5 - -

Ρ (g/mL) 0.795 0.80196 0.7978 0.79825 0.00350

Sample Calculation for mol of NaOH

of NaOH 5.5 0.02 NaOH 0.000110

1000 1000

mL NaOH mLmol

(A1)

Sample Calculation for propionic acid concentration

of acid 0.000110

0.000011mL of sample 10

mol mol mol Acid

mL (A2)

Sample Calculation for propionic acid mass flow rate

1.165 74.1

mass of acid= flow rate 0.000011 0.000949 /sec

mol mL g Acid g s

mL mol (A3)

Sample Calculation for volume of propionic acid

volume of acid = volume×molecular weight×density

74.1 990.000011 100 0.0823

Acid

mol g g mL mLmL mol mL

(A4)

Sample Calculation for volume of diesel

volume of diesel = total volume - volume of acid = 100mL - 0.0823mL = 99.9 mL (A5)

Sample Calculation for mass flow rate of diesel

volume of diesel 99.9 mL 0.798 density of feed =

time of sample 94sec mL

g (A6)

Sample Calculation for YA

mass of acid 0.000949 / = 0.00111

mass of diesel 0.849 / A

g sY

g s (A7)


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41

Oscillation #1 – 144 oscillations/minute – 0.7cm amplitude

Table A2. Raffinate flow properties for Oscillation #1.Raffinate

Trial Volume (mL) Time (seconds) Flow rate (mL/sec)1 100 94 1.064

2 100 75 1.3333 100 91 1.099Average - - 1.165StandardDeviation

- -0.147

Table A3. Extract flow properties for Oscillation #1.Extract

Trial Volume (mL) Time (seconds) Flow rate (mL/sec)1 100 73 1.3702 100 70 1.4293 100 70 1.429

Average - - 1.409StandardDeviation

- -0.0339

Titration – Raffinate

Table A4. Titration raffinate properties for Oscillation #1.Trial Volume

Raffinate (mL)

Volume NaOH

(mL)

mol NaOH mol propionic

acid

Propionic acid

concentration

(mol/mL)1 10 5.5 0.000110 0.000110 0.0000112 10 5.2 0.000104 0.000104 0.00001043 10 5.1 0.000102 0.000102 0.0000102

Table A5. Titration raffinate properties for Oscillation #1 continued.

mass Acid (g/s) Vacid (mL) Vdiesel (mL) mass Diesel (g/s) YA ya*

0.000949 0.0823 99.9 0.849 0.00112 0

0.000898 0.0778 99.9 1.06 0.000844 0

0.000881 0.0763 99.9 0.877 0.00101 0Average

0.0546 g/min

- -Average

55.8 g/min

Average

0.000989

Average

0StandardDeviation

0.00216 g/min- -

StandardDeviation7.01 g/min

StandardDeviation0.000138

StandardDeviation

0

(More appendices followed in the original report…)


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42

CHBE 4210 – Bioprocess Unit OperationsDr. Yonathan Thio – Ms. Jacqueline Snedeker Lab 6: Novel Transdermal Drug Delivery

(NOTE: This is not the same as the Transdermal delivery lab that we are doing in 4210!)Group 14: Larry Brown and *Moe Green

Dates Performed: July 6, 2016 – Date Submitted: July 13, 2015ABSTRACT

(See Abstract section in Style Guide for an

example. 275 word limit.)

INTRODUCTION Drug delivery has two important criteria: drug

concentration in blood plasma and effective

period. Oral medication usually fails to

achieve a steady and extended drug

concentration in the body. It requires periodic

administration ranging from several hours to a

couple of days due to rapid drug elimination in

the body. Furthermore, it experiences “first-

pass” effects in the liver, in which the drugs are

typically degraded or metabolized before

reaching the blood plasma, reducing the drug

concentration.1

To overcome such limitations, we

developed a novel transdermal drug delivery that

administers drugs across the skin. In this case

study, we designed an estradiol patch and

compared it to traditional oral medication. The

objective of the study was to determine the

effectiveness of transdermal delivery of estradiol

compared to other methods. Estradiol, a major

form of estrogen secreted by the human ovary, is

typically administered to treat menopause

symptoms. To meet our objective, we compared

the drug concentration in blood plasma between

an estradiol patch and an estradiol pill. (165

words. Limit is 170)

THEORY

(Here, you would lay out the key equations and

models used to analyze your data. 275 wordlimit. See Theory section in Style Guide for an

example.)

APPARATUS AND PROCEDURE ( Here, you would briefly describe yourapparatus and insert a diagram of theapparatus. You would also briefly describe the

procedure, noting in particular any deviations

from the lab manual.) Studies were conducted on 40

postmenopausal women. They were divided into

four groups of ten: three groups receiving

estradiol patches containing different amount of

estradiol (2.0, 4.0, and 8.0 mg), and one group

receiving pills every 24 hours. We took blood

samples from the women every two hours for

three days (=72 hours), and the concentration of

serum estradiol was measured by

radioimmunoassay with respect to base-line

studies performed on the women prior to

estradiol administration.2 Key safety issues were

as follows: (list any key safety issues here, as

well as standard safety protocol.)

(Word limit is 150 words.)


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RESULTS & DISCUSSION ( Note: this R&Dexample is only 350 words. Yours will be closer

to 450-550 words because in most cases youhave multiple objectives.) To determine the effectiveness of transdermal

drug delivery, the collected data were graphedwith respect to the baseline estradiol level in

blood plasma, as shown in Figure 1. (note:

Format of figure is incorrect — see Style Guide

for instructions on formatting figures/tables.)

Figure 1. Comparison of drug concentrations of 2.0,

4.0, and 8.0 mg of estradiol patch and 2.0 mg oral

medication.

The result shows that among women

receiving the estradiol patch, the concentration

of serum estradiol achieved steady state after 4

hours (as shown in Figure 1). The mean

concentrations of serum estradiol for the 2.0,

4.0, and 8.0 mg patches increased by 32, 67, and

81 pg per ml above baseline, respectively, at

steady state. By comparison, the group

receiving estradiol pill had a mean serum

concentration of estradiol 59 pg per ml above

baseline.

Transdermal drug delivery achieved a higher

concentration of estradiol in the blood plasma,

with less of the drug, than the oral medication.

When using the estradiol patch containing 4.0mg

of estradiol, the mean concentration of serum

estradiol increased by 67 pg per ml, while for

three estradiol pills each containing 2.0mg of

estradiol, concentration increased by 59 pg per

ml. Therefore, transdermal drug delivery is

more cost-effective by requiring less estradiol.

We also observed steadier estradiol

concentration from the group receiving the

estradiol patch than from the group with oral

medication. Using the estradiol patch, a steady

concentration of estradiol in blood plasma was

achieved over 62 hours. In contrast, the oralmedication yielded a sharp decline of the drug

concentration and required daily administrations

to be therapeutically effective.

The steady concentration of estradiol was due

to the constant driving force in estradiol flux

into skin. Once the stratum corneum (the

outermost skin layer) is saturated with drug, the

patch provides a steady influx of drug driven bythe concentration difference of drug between

skin and drug reservoir in the patch.

The results suggest that the estradiol patch can

be a substitute for estradiol pill, and may even

be a better method for estradiol delivery. The

estradiol patch achieved a steadier and longer

drug concentration than the estradiol pill.

Furthermore, the estradiol patch avoided highinitial spikes shown in the estradiol pills, which

possibly cause side effects.

CONCLUSIONS & RECOMMENDATIONS Our study accomplished the objectives by

illustrating the advantages that transdermal drug


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delivery has over oral administration. First, it

minimized degradation or metabolization of

drug, yielding higher concentration in blood

plasma. Second, it provided sustained release of

drugs for several days to a week. Furthermore,

results showed that tight regulations on the

dosage can be accomplished due to ease of

control.

Despite these advantages, transdermal drug

delivery can be only applied to drugs that meet

certain criteria. Drugs must have low molecular

mass, less than 500 DA, high lipophilicity, and

low required dose due to the low permeability ofthe stratum corneum. Overcoming this low

permeability is a major challenge in transdermal

drug delivery.

Recommendations to improve this lab

include testing transdermal delivery of other

drugs such as caffeine and nicotine in order to

expand the application of this novel patch. We

also recommend expanding the clinical trials inorder to obtain more reliable data. (155 words)

REFERENCES 1. Shah, V. P. Topical Drug Bioavailability,

Bioequivalence, and Penetration; Springer:

Washington, DC, 1993; pp 71-88.

2. Guy, R. H.; Hadgraft, J. Transdermal Drug

Delivery, Informa Health Care: Seattle, WA,

2003; pp 1; 5; 72.

3. Prausnitz, M. R.; Mitragotri, S.; Langer, R.,

Current Status and Future Potential of

Transdermal Drug Delivery. Nature Reviews

2004, 3, 115-124.

4. Henzl, M. R.,; Loomba P. K. Transdermal

Delivery of Sex Steroids for Hormone

Replacement Therapy and Contraception: A

Review of Principles and Practice. The

Journal of Reproductive Medicine 2003, 7 ,

525-540.

5. Physician’s Desk Reference, 48th ed. Thomson

PDR: Montvale, NJ, 1994; p 822.

Note: Nomenclature and Appendices would follow on the subsequent pages. Nomenclatureand Appendices do not need to be presented in

two-column format.


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Nomenclature


A surface area m2

C pair heat capacity of air J/kg/K

C pc heat capacity of copper J/kg/K

C pw heat capacity of water J/kg/K

DAB diffusivity of an air water system m2/s

Eacc energy accumulated in a system J

Eg energy generated in a system J

Ein energy entering a system J

Eout energy leaving a system Jh convective heat transfer coefficient W/K/m2

Hfg mole heat of vaporization of water J/kg

Jix molal flux relative to molal average velocity -

K air thermal conductivity of air W/K/m2

K c thermal conductivity of copper W/K/m2

K w thermal conductivity of water W/K/m2

Lc Length of copper cylinder m

M molecular weight g/mol


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Appendix A: Concentration Data

Table I A. Blah blah blah blah.

- - -

Table II A. Blah blah blah blah.

SLOPEINTERCEPT

R 2

Appendix B: ANOVA calculations

Table I B. Blah blah blah

Source of Variation SS df MS F P-value F crit

Between Groups 0.000205

Within Groups 0.000155

Total 0.00036

ANOVA shows that results are significant (Fcalc>Fcrit) at a 90% confidence level.


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Appendix A: Scientif ic Wri ting & Format Specs

The “Grammar” of Scientific Writing & Format Specifics of the ChBE Lab

Report

Every field has its own “language”— that is, its own specific, standardized, conventionalways of using language and formatting text. One could call this the “grammar of a profession”

or the discourse conventions of a community. This section outlines aspects of the “grammar” ofchemical engineering that are significant to lab report writing.

1. Verb Tense: In your lab report, things that occurred in the past should be written about in the past tense.Everything in the experiment occurred in the past. There are two exceptions:

a. Use the present tense when writing about current events (industrial applications, forexample).This use of the present tense will occur mainly in the Introduction.

b. Use the present tense when writing about things that are eternally in the present, thingsthat are unaffected by time (equations, figures, tables, and theoretical ideas). Equation 9always “yields”; Figure 3 always “shows.” To clarify: if you used the past tense in thesesituations, you would be suggesting that something different holds true now: “Equation 9

yielded Equation 10 (at one time), but now Equation 9 yields something else (because ofnew research, theory, etc.).”

This “rule” applies mainly in the Theory section, but it will also come into play in the Results and Discussion section when you are explaining your graphs and tables. (e.g., “Figure 3 shows that when time increased, temperature decreased.” NOTE: the verbtied to the “thing” in the perpetual present is in the present tense (“shows”), but the verbs thatrelate to the actual experiment are in the past tense (“increased” and “decreased”)).

2. Passive vs. Active Voice:Although you should avoid passive voice as much as possible in all types of writing, thereare situations when passive constructions are appropriate in scientific writing.

NOTE: Passive voice, passive verbs, or passive constructions occur when there is no agent

in the sentence — that is, there is no one or thing doing the action (EX. “A bomb was droppedon Hiroshima.” This is passive voice because the sentence doesn’t indicate WHO or WHAT“dropped the bomb.”

labreport style guide

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