CHEN 4460

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Class Overview Introduction
CHEN 4460 Process Synthesis, Simulation and
Optimization Dr. Mario Richard EdenDepartment
of Chemical EngineeringAuburn University Lecture
No. 1August 23, 2004
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My Background

• Education
• M.Sc. (Chem. Eng.), Tech. Uni. of Denmark (1999)
• Minor Thesis Design and Simulation of Petlyuk
  Sequences
• Master Thesis Operability of Three Component
  Distillation
• Ph.D. (Chem. Eng.), Tech. Uni. of Denmark (2003)
• Property Based Process and Product Synthesis and
  Design
• Professional Experience
• Assistant Professor, Auburn University (2004
  present)
• Process simulation, design and optimization
  (senior classes)
• Visiting Lecturer, Auburn University (2002
  2003)
• Process simulation, design and optimization
  (senior classes)

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Location of Denmark
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A Few Facts About Denmark

• Constitutional Monarchy
• A little smaller than the state of Alabama (not
  including Greenland)
• Population approximately 5500000.
• National sport SOCCER!

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Class Overview 13

• Lectures (Start Today)
• Monday 900 950 AM (Aerospace 155)
• Additional lectures may be held during lab
  sessions
• Labs (Start Next Week Hopefully)
• Sections
• I Tuesday Thursday 1100 AM - 1220 PM
  (Textile 230)
• II Tuesday Thursday 630 PM - 745 PM (Textile
  230)
• Comments
• Simulation workshops can be completed in one lab
  session
• TA will be available during ONE session for each
  section
• Scheduling problems with the evening lab sessions
  can be overcome by attending the Thursday morning
  lab session instead.

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Class Overview 23

• Teaching Assistant
• Ahmed Abdelhady (Graduate student)
• Office hours will be announced once lab
  assignments are finalized
• Will meet with entire class Tuesday August 24 at
  1100 in Textile 230 to discuss lab schedule and
  assignments
• Course Materials
• Textbook
• El-Halwagi, M. M. "Pollution Prevention through
  Process Integration Systematic Design Tools",
  Academic Press, San Diego, 1997
• Eden, M. R., Abdelhady A. "ASPEN Lab Notes",
  Auburn University (2004) (Will be available at
  Engineering Learning Resources Center soon).

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Class Overview 33

• Grading
• Simulation workshops (10)
• Simulation Project Workshop 7 (10)
• Simulation exam (20)
• Homework (20)
• Midterm (20)
• Final exam (20)
• Instructors Office Hours
• Official Wednesday 1030 AM 1200 Noon
• Reality Any time the door is open

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Class Introduction 130

• Motivating Example 1 Acrylonitrile Process

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Class Introduction 230

• Recycle Wastewater to Distillation

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Class Introduction 330

• Recycle Wastewater to Scrubber

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Class Introduction 430

• Recycle Wastewater to Boiler

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Class Introduction 530

• Recycle Wastewater to Scrubber and Boiler

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Class Introduction 630

• Recycle Wastewater to Scrubber and Boiler while
  adding fresh Boiler Feed Water (BFW)

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Class Introduction 730

• Cleanup Wastewater Recycle to Scrubber and Boiler
  to avoid adding fresh Water (BFW)

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Class Introduction 830

• Cleanup Steam Condensate and Recycle Wastewater
  to Scrubber and Boiler

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Class Introduction 930

• Cleanup Steam Condensate, Off-gas Condensate and
  Wastewater Recycle to Scrubber and Boiler

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Class Introduction 1030

• Cleanup Steam Condensate, Off-gas Condensate and
  Wastewater Recycle to Scrubber and Boiler

Separation Units Alternative Number 1
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Class Introduction 1130

• Cleanup Steam Condensate, Off-gas Condensate and
  Wastewater Recycle to Scrubber and Boiler

Separation Units Alternative Number 2
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Class Introduction 1230

• Cleanup Steam Condensate and Wastewater Recycle
  to Scrubber and Boiler

Separation Units Alternative Number 1
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Class Introduction 1330

• Cleanup Steam Condensate and Wastewater Recycle
  to Scrubber and Boiler

And so on. ALMOST INFINITE ALTERNATIVES!!!!
Separation Units Alternative Number 2
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Class Introduction 1430

• Actual Optimum Solution

How can this solution be generated systematically?
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Class Introduction 1530

• Required Steps
• Task Identification
• Stream Rerouting (from where to where)
• What transformations are required (separation,
  biotreatment)?
• Should separations be used to clean up wastewater
  for reuse? If yes, then what and how much should
  be removed from which streams?
• Should the operating conditions of some units be
  changed? If yes, then which units and which
  operating conditions?
• .
• Unit Selection
• Extraction, Stripping, Ion Exchange, Absorption?
• Which solvents?
• What type of columns?
• ..

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Class Introduction 1630
We will learn how to do all of
this systematically!

• Required Steps (Continued)
• Generation of Alternatives
• Reroute Absorption
• Reroute Absorption Extraction
• Stripping Ion Exchange
• .
• Interconnection of Alternatives
• Traditional Approach (Until late 80s)
• Brainstorming among experienced engineers
• Copy the last design we or someone else did!

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Class Introduction 1730

• Limitations of Traditional Approach
• Not possible to enumerate the infinite
  alternatives
• Time and money intensive
• Is not guaranteed to come close to optimum
  solutions (except for very simple cases or
  extreme luck)
• Does not shed light on global insights and key
  characteristics of the process
• Severely limits groundbreaking and novel ideas
• State of the Art Process Synthesis, Simulation
  and Optimization
• Systematic, fundamental, and generally applicable
  techniques can be learned and applied to
  synthesize optimal designs for improving process
  performance.

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Class Introduction 1830

• Process Synthesis
• Activities in which the various process elements
  are combined and the flowsheet of the system is
  generated so as to meet certain objectives.
• In process synthesis we know process inputs and
  outputs and are required to revise the structure
  and parameters of the flowsheet (for retrofitting
  design of an existing plant) or create a new
  flowsheet (for grass-root design of a new plant).

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Class Introduction 1930

• Process Synthesis Steps
• Task Identification
• Unit Selection
• Generation of Alternatives
• Interconnection of Alternatives and Selection
  from among the Alternatives.
• Process Analysis/Simulation
• Analysis/simulation is aimed at predicting how
  the synthesized process will perform.
• It involves the decomposition of the process into
  its constituent elements (e.g. units) for
  individual study of performance.

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Class Introduction 2030

• Process Analysis/Simulation (Continued)
• Detailed process characteristics (e.g. flowrates,
  compositions, temperature, pressure, etc.) are
  predicted using analysis techniques, e.g.
  mathematical models, empirical correlations and
  computer-aided process simulation tools such as
  Aspen Plus.

PROCESS DESIGN PROCESS SYNTHESIS PROCESS
ANALYSIS
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Class Introduction 2130

• Motivating Example 2 Refinery Process

Problem Naphtha and gas oil contain objectionable
materials (e.g. sulfur), and unsaturated
hydrocarbons (e.g. olefins and gum-forming
unstable diolefins) that should be converted to
paraffins. Design Objectives Synthesize a a
revised process to remove sulfur (and other
objectionable materials) and stabilize olefins
and diolefins.
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Class Introduction 2230

• Process Synthesis Steps
• Task Identification
• React naphtha and gas oil with hydrogen to remove
  objectionable materials and stabilize (saturate)
  olefins and diolefins.
• Unit Selection
• Hydrotreating and hydrodesulfurization catalytic
  processes.
• Generation and Interconnection of Alternatives
• Add hydrotreating/hydrodesulfurization to each
  stream. Purchase fresh hydrogen and feed to units.

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Class Introduction 2330

• Revised Refinery Process

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Class Introduction 2430

• Acrylonitrile Process Revisited

What is wrong with this design from a water
perspective? No integration of mass (water)
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Class Introduction 2530

• Motivating Example 3 Pharmaceutical Process

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Class Introduction 2630

• Straightforward Solution

What is wrong with the energy usage in this
synthesized flowsheet? No integration of energy
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Class Introduction 2730

• Process Integration
• A holistic approach to process design,
  retrofitting and operation which emphasizes the
  unity of the process.

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Class Introduction 2830

• Energy Integration
• A systematic methodology that provides a
  fundamental understanding of energy utilization
  within the process and employs this understanding
  in identifying energy targets and optimizing
  heat-recovery systems.
• Mass Integration
• a systematic methodology that provides a
  fundamental understanding of the global flow of
  mass within the process and employs this
  understanding in identifying performance targets
  and optimizing the generation and routing of
  species throughout the process.

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Class Introduction 2930

• Targeting Approach
• Performance targets for the whole system can be
  determined ahead of detailed design
• Process Integration Philosophy
• Big picture first Details Later
• This Class
• Lectures will focus on process synthesis and
  integration
• Labs will focus on Aspen simulation

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Class Introduction 3030

• Capabilities upon Completion of this Class
• How to simulate complete flowsheets and predict
  their performance.
• How to identify best achievable performance
  targets for a process WITHOUT detailed
  calculations.
• How to systematically enhance yield, maximize
  profit, maximize resource conservation, reduce
  energy, and prevent pollution?
• How to debottleneck a process?
• How to choose units and screen their performance?
• How to understand the BIG picture of a process
  and use it to optimize any plant?
• And much more.. ?