This book covers the application of methods and tools for energy optimization and process design. It focuses the application of these methods on petrochemical process units such as the aromatics process unit. The book provides practical methods and tools to industrial practitioners with the focus on improving industrial energy efficiency, reducing capital investment, and optimizing yields via better design, operation, and optimization. Broken down into six parts the book covers a range of topics including: Aromatics Process Description; Process Design Considerations; Petrochemical Separation Design; Process Integration; Process system optimization; Types of revamps; Equipment assessment; Common operating issues; and Troubleshooting case analysis to name a few.