CHEE 221 Chemical Processes and Systems Fall 2006

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CHEE 221Chemical Processes and Systems- Fall
2006 -
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Information Session for New CHEE/ENCH Students
Tuesday September 12 430 530 Dupuis
Auditorium

• Learn important information about our department,
  and meet the staff and faculty.
• Pizza will be served!

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CHEE 221 Chemical Processes and Systems

• CHEE 221 is an introductory stoichiometry course
  that prepares students to formulate and solve
  material and energy balances on chemical process
  systems at steady-state (i.e. no change with
  time), and is the foundation for future courses
  in
• thermodynamics (CHEM 244, CHEE 311)
• kinetics and reactor design (CHEE 321),
• unit operations and transport phenomena (CHEE
  412)
• process dynamics and control (CHEE 319, CHEE 434)
• The follow-up course, CHEE 222 Process Dynamics
  and Numerical Methods, builds on the material
  learned in CHEE 221, and introduces
• transient (time-varying) behaviour
• larger scale problems ? systems of equations

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Motivation for CHEE 221

• No universally accepted definition of chemical
  engineering exists. Today, almost every type of
  skilled work you can think of employs someone who
  was educated as a chemical engineer. Examples
  are
• Traditional chemical engineering mining, pulp
  paper, oil refining, materials (rubber, plastics,
  etc.), environmental
• Non-traditional chemical engineering
  microelectronics (semiconductor manufacturing),
  biotechnology (pharmaceutical production
  processes, genetic engineering etc.)
• Other medicine, law, business
• A similarity in all the chemical engineering
  systems is that the systems involve processes
  designed to transform raw materials into desired
  products. A typical problem in the design of a
  new or existing process is
• Given the amounts and properties of the raw
  materials, calculate amounts and properties of
  the products, or vice versa (use material and
  energy balances to solve)

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Material and Energy Balances

• Material and energy balances are simply the
  application of the laws of conservation of mass
  and energy, respectively, which relate the inputs
  and outputs of manufacturing systems, power
  plants and the human body.
• Law of Conservation of Mass states that matter
  can neither be created or destroyed
• Law of Conservation of Energy states that energy
  can neither be created or destroyed (1st Law of
  Thermodynamics)
• A balance on a conserved quantity (i.e. mass or
  energy) in a system may be written in the
  following general way

Accumulation (In Out) (Generation
Consumption)
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Significance of Material and Energy Balances

• The significance of material and energy balances
  are they
• Provide a basis for modeling on paper (or by
  computer) systems that would be difficult and/or
  expensive to study in the lab
• Assist in the synthesis of chemical processes,
  and evaluation of design processes
• Guide the analysis physical systems
• Provide a basis for estimating the economic costs
  and benefits of a project

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Textbook Problems Versus Real Life Problems

• Textbook Problems
• are clearly defined
• have only one correct answer
• have exactly the right amount of data needed to
  solve the problem
• are designed to stress concepts and execution
  (this course)
• Real Life Problems
• may have difficulty defining what the real
  problem is
• may not have all the data required to solve the
  problem, requires use of approximate correlations
  or assumptions based on common sense or
  experience
• have more than one correct answer, each with
  their advantages and disadvantages

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CHEE 221 Textbook

• Elementary Principles of Chemical Processes 3rd
  Edition, 2005 by Richard Felder and Ronald
  Rousseau
• Mandatory!! Needed for assignments and contains
  all the concepts covered in class
• Contains useful data tables and conversion
  factors (Appendix B and inside the front and back
  covers)
• Test Yourself questions (with answers!) located
  throughout the text help ensure you understand
  the required concepts
• CD that accompanies the text contains interactive
  tutorials, a physical property database and a
  visual encyclopedia of chemical engineering
  equipment
• Student workbook contains detailed outlines of
  solutions to selected chapter-end problems

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CHEE 221 Objectives

• At the completion of this course, you should be
  able to
• Given a process description,
• draw and fully label a flowchart
• choose a convenient basis of calculation
• for multiple unit processes, identify subsystems
  for which balances might be written
• perform a degree-of-freedom analysis for the
  overall system and each possible subsystem
• formulate and simplify the appropriate material
  and energy balance equations, and perform the
  necessary calculations.
• You should be proficient at performing these
  analyses for single-unit and multiple-unit
  processes, for processes involving recycle,
  bypass or purge streams, and for systems
  involving reactions.

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CHEE 221 Objectives

• Understand and apply the first law of
  thermodynamics (conservation of energy),
  calculate energy and enthalpy changes using
  tabulated data and heat capacities, and construct
  energy balances on closed and open systems.
• Be familiar with basic processing terminology
  (batch, semi-batch, continuous purge and
  recycle) and standard operations (reaction,
  distillation, absorption, extraction,).
• Have a sense why these basic skills are required
  and important for all chemical engineers,
  independent of their final career choice.

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CHEE 221 Assessment

• Assignments 30
• Approximately 7 9 problem sets consisting of 4
  6 questions of which only 2 3 questions are
  marked
• Students may work together on assignments but
  everyone must submit a copy for grading, and the
  name(s) of your partner(s) must be written on
  your assignment
• Submit assignments to CHEE 221 drop box (outside
  Dupuis 215) by noon on their due date
• Midterm Exam 25
• Closed book exam based on material balances
  (Chapter 4 of Felder and Rousseau)
• Date, 90 minutes in length
• Final Exam 45
• Closed book exam based on the entire terms work
• Date TBA, 3 hours in length

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Lectures
Humphrey Hall 102
Lecture notes in the form of PowerPoint slides as
well as assignments, solutions, old exams, and
any announcements pertaining to the course will
be posted on the course website
http//www.chemeng.queensu.ca/courses/CHEE221/
Lectures will address the main course concepts
and the problem solving procedures to be used in
CHEE 221. The concepts will be demonstrated and
reinforced by working through examples on the
blackboard (with your participation!). Please
bring copies of the lecture notes with you to
each class.
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Tutorials

• Fridays 930 1020 in Dupuis Auditorium
• TA led sessions in which practice problems will
  be worked through and questions regarding the
  assignments will be answered
• Always bring a calculator and your textbook
• Course TAs
• Patrick Egbunonu (patrick.egbunonu_at_chee.queensu.c
  a)
• Ula El-Jaby (ula.el-jaby_at_chee.queensu.ca)
• Matt McMahon (matt.mcmahon_at_chee.queensu.ca)

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CHEE 221 Course Outline
The concepts of this course are relatively easy,
but you need lots of practice in order to execute
the calculations well. Practice, practice,
practice!!