Exploration - Understanding Data: Lets Make Coffee! Lesson 1: What - - PowerPoint PPT Presentation

Exploration - Understanding Data: Let’s Make Coffee!

Lesson 1: What is Chemical Engineering?

What is Chemical Engineering?

q What are some things that you think chemical

engineers do?

q Where do you think chemical engineers work?

Meet Melanie, Chemical Engineer

https://www.youtub e.com/watch?v=k- 7B_YfHWXQ https://www .youtube.co m/watch?v= RJeWKvQD9 0Y

There are different types of chemical engineers.

Process Engineers Product Engineers

Assignment: chemical engineering

q Air and Water Quality q Agriculture q Cell and Tissue Engineering q Computing q Energy q Foods q Forest Bioproducts q Fuels and Petrochemicals q Industrial Safety and

Operations

q Materials Engineering q Nanotechnology q Nuclear Engineering q Pharmaceuticals q Sustainability, Reuse, and

Recycling

Research and describe a specific process technology or product that chemical engineers work on. Describe how chemical engineers add value to the process or product. Be specific and provide details in describing what they do. (At least 150 words)

Can brewing coffee be a chemical engineering challenge?

q What happens when you brew coffee? q How can you brew strong coffee?

n Think (2 minutes): Given whole coffee beans and

water, what could you do to make strong coffee? List these in your engineering notebook.

n Pair (2 minutes): Compare answers with your team mates.

Add to the list in your engineering notebook.

n Share: We will generate a class list of ideas. Add to the list

in your engineering notebook.

How can we measure coffee “strength”?

q Given a cup of coffee, how can you tell how “strong”

it is?

n What does it look, taste, smell, or feel like as compared to

a “weak” cup of coffee?

n Are there any quantities you can measure to quantify a

cup of coffee as “strong” or weak”?

q In your groups, think of at least two quantitative and

two qualitative ways to analyze coffee strength. Note these in your engineering notebooks.

What are potential qualitative and quantitative test methods?

q Quantitative Test Methods involve measuring

specific quantities and ensuring measurements match desired set points Examples: pH, concentration, viscosity, density

q Qualitative Test Methods compare qualitative

• bservations to expected characteristics

Examples: color, taste, smell, visual appearance

The chemistry of brewing coffee

q What happens chemically when coffee grounds are

placed in water?

q Thousands of different compounds are extracted

from the coffee grounds into the water.

n These compounds are responsible for qualities such as

aroma, acidity, taste, color, and concentration of caffeine.

n The rate and amount of extraction of these compounds is

dependent on factors such as the size of the coffee grain, the temperature of the water that the coffee is placed in, and the amount of coffee grain present.

Concocting the Perfect Cup

• f Coffee (Courtesy of Science Friday)

http://sciencefriday.com/videos/concocting-the-perfect-cup-of-coffee-2/

https://www.youtube.com/watch?v=_NCPQMC2L1U

The chemistry of brewing coffee

q Here are a few of the compounds that get extracted

from coffee grounds. How measure concentration?

bitter taste, brown color, and acid reflux

Measuring Concentration

q Molecules that are formed in the coffee brewing

process produce ions.

n From chemistry we know that migration of ions produces

an electrical current (conductivity).

n The higher the amount of ions in a solution, the higher the

conductivity of the solution.

q Conductivity can therefore be used as a measure of

concentration.

n Higher conductivity à stronger coffee

q Measures concentration indirectly by measuring electrical

conductivity (EC) across one centimeter of the solution.

q High EC = Lots of ions in solution = High concentration of

extracted coffee molecules.

q The unit of conductivity is inverse of ohm (ohm-1), also known as

the “mho” in μS.

The Conductivity Sensor

q In your Engineering Notebook:

n Chemical Engineering Professions Research Assignment n Notes from Think-Pair-Share n Qualitative and Quantitative Measurement Methods

q particularly proud of or would like me to see.

Due End of Class Oct 17/18

Homework and What’s Next

q Be working on your research project into chemical

engineering fields and professions.

q Next time, we will explore how a chemical engineer

might approach brewing “the perfect cup of coffee”.

Lesson 2: Designing Coffee

• r

Brewing the Perfect Coffee through Chemical Engineering

Exploration - Understanding Data: Let’s Make Coffee!

Your Coffee Brewing Task

EYW Coffee Co. provides high-quality ready-to-drink coffee brews. They have just sent you a memo regarding a new project proposal: Having experienced much success from our regular strong brews, we have decided to expand into an untapped market: lighter brews for people who enjoy just a hint of coffee without bitterness. Instead of the standard coffee conductivity of 1800 µS, our light brew will have a conductivity of 300 µS when brewed in deionized water. We start with whole coffee beans and water. Our processing plant only has a grinder, heater, and brew tank, so we can only adjust particle size, temperature, residence time, and the coffee/water ratio. Examine different conditions and help us determine which combination will give us the desired cup of coffee in a consistent and efficient manner while considering trade-offs.

What variables are involved in our experiment?

q Dependent - What are we measuring?

n Coffee conductivity

q Independent - What are we changing?

n Coffee/water ratio n Temperature n Particle size n Residence time

q Controlled - What must stay constant?

n Coffee bean brand and type n Water quality

What are the ranges of our independent variables?

Low High Coffee/Water Ratio 0.01 g/mL 0.05 g/mL Temperature Ambient

(approximately 20-25°C) 65-75°C

Particle Size whole bean fine ground For Residence Time, we will take conductivity measurements (about 5 seconds in duration) every minute for 15 minutes.

Eng 8 Kontor, Zachary Coffee Concentration Temperature Bean or Ground Eng 1 Gregory, Cole Low High Whole Bean Eng 1 Tatum, Maddie High High Whole Bean Eng 1 Johnson, Holly High Low Whole Bean Eng 1 Gaige, Casey High Low Ground Eng 1 Mueck, Ben Low High Ground Eng 1 Osman, Deen Low Low Whole Bean Eng 1 Hulett, Blake Low Low Ground Eng 1 Both Teams High High Ground

Eng 8 Kontor, Zachary Coffee Concentration Temperature Bean or Ground Eng 1 Gregory, Cole Low High Whole Bean Eng 1 Tatum, Maddie High High Whole Bean Eng 1 Johnson, Holly High Low Whole Bean Eng 1 Gaige, Casey High Low Ground Eng 1 Mueck, Ben Low High Ground Eng 1 Osman, Deen Low Low Whole Bean Eng 1 Hulett, Blake Low Low Ground Eng 1 Both Teams High High Ground

Let’s try it – brew some coffee!

❑ Set up your notebook for your experiment

■ Document your assigned condition ■ Create a data table for conductivity over time ■ Leave a space to record initial temperature and initial

conductivity

❑ Follow the experimental procedures and record

your data in your engineering notebook

❑ Add your data to the class data set

Analyze Class Data Set

❑ What do you notice about the class data set? ❑ What do you think a graph of conductivity (µS)

versus time will look like?

❑ How can we make sure we get consistent data

moving forward?

How many experiments do we need to run?

❑ Recall our variables:

■ Coffee/water ratio: 0.01 to 0.05 g coffee per 1 mL water ■ Temperature: 40° C to 50° C (low) to 65° C to 75° C (high) ■ Particle Size: fine ground to whole bean

❑ Let’s agree to test only the extremes of each variable. ❑ How many different experiments (different

combinations of factors) are possible?

❑ Predict the results of each experiment ❑ How many trials should we run for each combination

• f factors?

Design of Experiments (DoE/DoX)

❑ Design of Experiments refers to the design and

planning of an experiment to test the effect of factors

• n a controlled variable.

■ We must check eight combinations in our three-factor DoE.

❑ For efficiency, teams will share data to create a class

data set.

❑ Each group will test four combinations. ❑ If your group finishes early, test more combinations to

increase the data in our data set. (Why?)

❑ Record and sketch graphs of your data in your

engineering notebooks.

q Place post-it notes on the appropriate pages in your notebook to

denote the following items:

n Coffee Brewing Challenge n Fixed and Variable Factors (with ranges) n Experimental Data (trial) n Experimental Data (assigned combinations)

q Write down the name of the appropriate item on each post-it. q Place a post-it in your notebook for anything else you are

particularly proud of or would like me to see.

Notebook Check

Homework and What’s Next

q Be working on your research project into chemical

engineering fields and professions.

q Next time, we will discuss how to analyze the data

that we have collected.