This text presents the fundamental concepts of how mathematical models of chemical processes are constructed and demonstrates their application to the simulation of two of the very important chemical engineering systems: the chemical reactors and distillation systems. The book provides an integrated treatment of process description, mathematical modelling and dynamic simulation of realistic problems, using the robust process model approach and its simulation with efficient numerical techniques. Theoretical background materials on activity coefficient models, equation of state models, reaction kinetics, and numerical solution techniquesneeded for the development of mathematical modelsare also addressed in the book. The topics of discussion related to tanks, heat exchangers, chemical reactors (both continuous and batch), biochemical reactors, distillation columns (both continuous and batch), equilibrium flash vaporizer, and refinery debutanizer column, contain several worked-out examples and case studies to teach students how chemical processes can be measured and monitored using computer programming. This book is designed for senior level undergraduate and first-year postgraduate level courses in Chemical Process Modelling and Simulation. The book will also be useful for students of petrochemical engineering, biotechnology, and biochemical engineering. It can serve as a guide for research scientists and practising engineers as well.