Physico/Chemical Processes of Environmental Engineering

Physico/chemical processes are central to many Environmental Engineering applications, but also are broadly applied in other engineering disciplines. This course is designed to present fundamental principles of physico/chemical processes that are commonly used in Environmental Engineering (and other disciplines). The course is divided into three modules. Module I addresses transport phenomena and reactor theory. The tools presented in Module I are central to the descriptions of processes that are presented in the remainder of the class. Module II addresses physical separation processes ( i.e. , processes for separation of particles from fluids). Module 3 addresses processes that are used to bring about non-microbially-mediated) transformations. The processes that are described are particularly relevant to water treatment, and many examples presented in the class are from the water treatment domain. But opportunities to apply these principles in other settings are also pursued in this class. Specifically, principles taught in this class are relevant to air pollution dynamics and control, flow through porous media, and transformations of non-aqueous media (food products, air, surfaces).

Week 1:

• Contemporary Environmental Problems
• Categories of Processes
• Mass Balances
• Fundamentals of Transport Phenomena
  • Advection, Diffusion, Dispersion

Week 2:

• Interphase Transport

  • Concepts Involved in Interphase Transport of Heat
  • Hooke's Law
  • Gas-Liquid Transfer: Two-Film Model
  • Gas-Liquid Transfer Dynamics in Semi-Batch Reactor
  • Reaction Kinetics
  • Kinetic Expressions I and II

Week 3:

• Basic Reactor Models
  • Batch Reactor
  • Ideal CFSTR Model
  • Ideal CFSTR at Steady-State
  • Conversion in an Ideal CFSTR
  • Ideal PFR at Steady-State
  • Ideal PFR

Week 4:

• Basic Reactor Models
  • CFSTR Cascade
  • PF with Longitudinal Dispersion
  • Plug Flow
• Residence Time Distribution Functions
  • RTD Concept and Characteristics
  • Experimental Methods: Pulse Test, Step Test

Week 5:

• Reactor Simulation Methods
  • Segregated Flow Model
  • Numerical Models
• Solid Fluid Separation Processes

Week 6:

• Gravity-Based Separation
  • Discrete Particle Settling, Turbulent Settling, and Laminar Settling
  • Drag Forces
• Ideal Settling Tank Model
  • Model Characteristics, Assumptions
  • Trajectory Approach
  • Particle Separation Efficiency
• Centrifuges

Week 7:

• Coagulation/Flocculation
  • Particle Surface Chemistry I and II
  • Colloidal Stability
  • Colloidal Destabilization Mechanisms
  • Coagulation with Metal Salts
  • Jar Testing
  • Smoluchowski Equation
  • Collision Frequency Functions
  • Fluid Shear

Week 8:

• Coagulation/ Flocculation; Filtration
  • Paddle Flocculators and Jar Test Apparatus
  • Filter Types
  • Slow and Rapid Sand Filters
  • Filter Media

Week 9:

• Filtration

  • Window, Modeling, Flow Through Porous Media, Energy Loss, Fluidization

Week 10:

• Adsorption
  • Langmuir Isotherm
  • BET Isotherm

Week 11:

• Ion Exchange
• Deionization
• Disinfection

Week 12:

• Disinfection
  • Halogen Equilibria
  • Halogen Electrochemistry
  • Effective Henry's Law Constant
  • Reactions Between Chlorine and Ammonia
  • Chlorination and Breakpoint

Week 13:

• Disinfection
  • DBPs
  • Dechlorination
  • Chlorine Disinfection Kinetics
  • Deviations from Chick-Watson
  • Peracids

Week 14:

• Disinfection
  • Photochemistry

Week 15:

• Disinfection
  • UV Disinfection Kinetics
  • UV Dose Distribution

Week 16:

• Gas: Liquid Transfer
  • Henry's Law
  • Air Stripping
  • Stripping of Volatile Compounds in Bubble Contactors
  • Gas Stripping