ChemE Lecture

8/11/2019 ChemE Lecture

1/46

Chemical Engineering

Summer@Brown

2011


2/46

August 28, 1859 - Titusville, Pennsylvania

Edwin Drake


3/46


4/46

Haifa, Israel

9 million tons (66 million barrels) of crude oil/ year


5/46

What is Chemical Engineering?

Basic sciences PLUS engineering fundamentals:

Convert raw materials into valuable products

Design and manufacture devices

This is accomplished by:

Chemical reactions (making and breaking of bonds)

Catalysis (accelerating chemical reactions)

Separation, purification of complex chemical mixtures


6/46

Famous Chemical Engineers

Linus PaulingNobel Prize in Chemistry, 1954,

Nobel Peace Prize, 1962

Jack WelchFormer CEO of General Electric

Lee RaymondExxonMobile chairman and CEO

Victor MillsInvented first disposable diaper

Robert GoreInventor of Gore-Tex

Samuel BodemanFormer United States

Secretary of Energy (2005-2009)


7/46

Convert Raw Materials into Valuable

Products

Crude OilGasoline, Jet Fuel, Monomers

MonomersPolymers (ethylene

polyethylene) Silicon crystalsSemiconductors, integrated

circuits

Inorganic PrecursorsCeramics Corn StarchHigh Fructose Corn Syrup


8/46

Design and Manufacture Devices

Chemical plants (paper, plastics, fertilizers)

Electronics

Biomedical devices (artificial kidney, hearts)

Diagnostic/Drug delivery devices

Novel materials (polymers, fibers, ceramic)

Energy devices (batteries, fuel cells)

Waste treatment solutions

Specialty chemicals (foods, flavors, fragrances)


9/46

Chemist vs. Chemical Engineer

Chemists:Design new molecules and

synthesizes new formulas

Work in grams of materials

Chemical Engineers: Design equipment and

processes for large-scale chemical

manufacturing

Work in tonnesof materials


10/46

Bhopal Gas Tragedy

Union Carbide India Limited pesticide plant,

Bhopal, India - December 2-3, 1984

1-naphthol chloroformate carbaryl


11/46

Factors leading to the Bhopal disaster

Caused >15,000 deaths

Use of hazardous chemicals (MIC) instead of less dangerousones

Storing these chemicals in large tanks instead of over 200steel drums.

Possible corroding material in pipelines Poor maintenance after the plant ceased production in the

early 1980s

Failure of several safety systems (due to poor maintenanceand regulations).

Safety systems being switched off to save moneyincluding the MIC tank refrigeration system


12/46

A Chemical Engineers Curriculum

Lots of Math, Chemistry and Physics

Fundamental Classes Heat and Mass Transfer

Chemical Thermodynamics Chemical Kinetics

Fluid Mechanics

Units of Chemical Processes: chemical reactors,bioreactors, distillation columns, heat exchangers

Design Chemical Processintegrate process unitswith regard to economics, safety and environmentalimpact


13/46

Job Opportunities


14/46

The Fundamentals


15/46

Black Box Theory

Device, system or object which can be viewed solely interms of its input, output and transfer characteristicswithout any knowledge of its inner workings

Examples:

Computer programming; software testing

Finance: market prediction

Climate change- weather prediction

Physics: Particle physics Hadron Collider

Human mind: fMRI Biological systems

Black box theory has been used in many fields ofscience and engineering


16/46

Refinery Operations


17/46

Evaporator

Converts Liquid -> Gas

Heat Exchanger

A(75C)A(30C)

Distillation Column

ABA + B


18/46

Process

Unit

Input/Feed Output

DistillationABA + B

Heat Exchanger

A(75C)

A(30C)

Blackbox

Unit

Operations


19/46

Process streams

Mass flow rate, m,

(kg/h)

Volumetric flow rate, V

(L/min)

.

.m

mass

time

.

Vvolume

time

. m V. .


20/46

Process

Unit

Input/Feed Output

DistillationABA + B

Heat Exchanger

A(75C)

A(30C)

Blackbox

Unit

Operations

m1, v1

. .

m2, v2

. .


21/46

The volumetric flow rate of CCl4 (= 1.595 g/cm3) in a

pipe is 100.0 cm3/min. What is the mass flow rate of

the CCl4?

Question 1


22/46

Process

Unit

Input/Feed Output

Min (kg CH4/h).

Mout (kg CH4/h).

Min!= Mout. .

Why?

1. Incorrect measurement2. Leakage

3. Adsorption onto the walls

4. Reacted away? Or generated as a product?


23/46

Conservation of Mass

What goes in must come out!!

At steady state, accumulation in system = 0:

No reaction:

Input + Generation - Output - Consumption = Accumulatio

Input - Output = 0

Input + Generation - Output - Consumption = 0


24/46

Each year 50,000 people move into a city, 75,000

people move out, 22,000 are born and 19,000 die.

Write a balance on the population of the city.

Question 2


25/46

A feed stream of pure liquid water enters an evaporator ata rate of 0.5 kg/s. Three streams come from theevaporator: a vapor stream and two liquid streams. Theflow-rate of the vapor stream was measured to be 4 X 106

L/min and its density was 0.004 kg/m3. The vapor streamenters a turbine, where it loses enough energy to condensefully and leave as a single stream. One of the liquid streamsis discharged as waste, the other is fed into a heat

exchanger, where it is cooled. This stream leaves the heatexchanger at a rate of 0.1893 kg/s. Calculate the flow rateof the discharge and the efficiency of the evaporator.

Question 3


26/46

One thousand kilograms per hour of a mixture of

benzene (B) and toluene (T) containing 50%

benzene by mass is separated by distillation into two

fractions. The mass flow rate of benzene in the topstream is 450 kg B/h and that of toluene in the

bottom stream is 475 kg T/h. The operation is at

steady state. Write balances on benzene andtoluene to calculate the unknown component flow

rates in the output streams.

Question 4


27/46

Question 5

Two methanol-water mixtures are contained in separate

flasks. The first mixture contains 40.0 wt% methanol, and the

second contains 70.0 wt% methanol. If 200 g of the first

mixture is combined with 150 g of the second, what are themass (m) and composition of the product?


28/46

Case Study:

High Fructose Corn Syrup


29/46

High Fructose Corn Syrup

Milestones

1957Process developed by Richard O. Marshall

and Earl R. Kooi

Up until 1970: sucrose used as a main sweetener

19751985HFCS introduced to processed

foods and soft drinks

Common forms: HFCS 42 and HFCS 55

Soft Drinks 95%

Baked Goods 25%

Diary 30%

Processed Foods 45%


30/46

Sold in a bushel: 56 pounds of wet corn

(48.1 lb of dry corn + 7.9 lb of water)

Milling Process

Corn Oil 1.6 lb

Cornmeal 2.5 lb

Animal Feed 12.5lb

Starch 31.5 lb

Water 7.9 lb


31/46

Extract Weight/Bushel Cost/Pound Cost/Bushel

Corn Oil 1.6 lb $0.27/lb $0.43/bushel

Cornmeal 2.5 lb $0.132/lb $0.33/bushel

Animal Feed 12.5 lb $0.044/lb $0.55/bushel

Starch 31.5 lb ? ?

Water 7.9 lb --- ----

$1.31/bushel

Raw Material Weight/Bushel Cost/Pound Cost/Bushel

Wet Corn 56 lb $0.047/lb $2.63/bushel

Cost Analysis of Harvesting Corn


32/46

Corn Starch High Fructose

Corn Syrup

Liquefication

G-G-G-G-G-G G, G-G, G-G-G

Saccharification

G-G, G-G-G G, G, G, G, G

Isomerization Glucose Fructose

-amylase

Glucoamylase

Glucose isomerase


33/46

Corn Starch

Other ExtractsStarch Purification

Liquefaction

Saccharification

Isomerization

Separator

55% HFCS42% HFCS

-amylase

plant

glucoamylase

plant

glucoisomerase

plant

3 hrs, pH 6-7, Initial: 300F, 30

min, Heat: 185F, 30 min, Cool:

140F, 30 min

40-90 hours, pH 4, 140F

30 min process, pH

7, 140-150F


34/46

Composition % Fructose % Glucose % Solid

HFCS 42 42 58 70

HFCS 55 55 45 70

Raw Material Weight/Bushel Cost/lb Cost/Bushel

HFCS 42 31.5 lb $0.18/lb $5.67

HFCS 55 31.5 lb $0.20/ lb $6.30


35/46

Extract Weight/Bushel Cost/Pound Cost/Bushel

Corn Oil 1.6 lb $0.27/lb $0.43/bushel

Cornmeal 2.5 lb $0.132/lb $0.33/bushel

Animal Feed 12.5 lb $0.044/lb $0.55/bushel

Starch 31.5 lb $0.18/lb $5.67/bushel

Water 7.9 lb --- ----

$7.42/bushel

Raw Material Weight/Bushel Cost/Pound Cost/Bushel

Wet Corn 56 lb $0.047/lb $2.63/bushel

Cost Analysis of Harvesting Corn


36/46


37/46

Operation Research and

Industrial EngineeringORIE, IEOR, OR-SE-IE


38/46

Originated in military efforts in WWII

Evaluates efficacy of the use of technology

Decision science: OR finds optimal solutions to

complex decision making process


39/46

Examples

1. Routing: Routes of buses so few buses are needed2. Floor-planning: layout of equipment of factory or

computer chip to reduce manufacturing time/ costs

3. Network optimization: set-up of telecommunicationsnetwork to maintain quality of service during

outages

4. Healthcare: How effective are various disease

treatments


40/46

Courses?

Statistics

Optimization

Probability theory

Decision analysis

Queuing/Game/Graph theories

Computer science/analytics


41/46

Financial Engineering

NOT a real engineering discipline!


42/46

Applies engineering methodologies to

problems in finance

Combines:

to predict

Design new financial instruments Models to help minimize financial risk

Math + Finance + Computer Modellin

Pricing + Hedging + Trading


43/46

Jobs?

Investment banks

Securities industry

Consulting firms (quantitative analysts)

Corporate finance/risk management roles in

other general manufacturing and service firms


44/46

Prerequisite: Bachelors incomputer science,

operation research

economics or math Master of Financial

Engineering

Master of QuantitativeFinance

PhDs in computer science

or applied mathematics

Face of a Financial Engineer?


45/46


46/46

Documents

ChemE Lecture