Separation Processes: Energy Efficiency and Techniques

This lecture introduces the fundamentals of separation processes, focusing on energy efficiency in separating CO₂ from air. The instructor discusses the theoretical energy penalty for this separation, highlighting that direct air capture industries report an energy penalty of at least 8 MJ/kg CO₂. The calculation of energy efficiency is demonstrated, revealing a low efficiency of around 6.25%. The lecture emphasizes the importance of understanding the cost and energy requirements for separation, illustrated through the Sherwood plot, which correlates material price with concentration. Various separation techniques are explored, including distillation, extraction, adsorption, and absorption, each exploiting differences in physical and chemical properties. The instructor explains the role of energy and mass separating agents in creating phases for separation. The lecture concludes with a discussion on the significance of thermodynamic principles and mass balance in designing effective separation processes, setting the stage for more detailed exploration in subsequent classes.