Sayed Alireza Hosseinzadeh Hejazi
Assistant Professor
Amirkabir University of Technology (Tehran Polytechnic)
Dr. Alireza Hejazi is an Assistant Professor at the Department of Chemical Engineering at Amirkabir University of Technology and heads the AUT Office of Sustainability. Prior to joining AUT, he was a Postdoctoral Research Associate at the Department of Chemical Engineering, Imperial College London (2017-2019). He holds a PhD and MSc in Chemical Engineering from the Department of Chemical and Materials Engineering at the University of Alberta in Canada.
Participates in
TECHNICAL PROGRAMME | Energy Fuels and Molecules
Helium, Lithium, and Trace Metals Extraction
Forum 17 | Technical Programme Hall 3
30
April
10:00
11:30
UTC+3
Helium, a strategic element with unparalleled properties, is indispensable across a vast array of modern applications, ranging from critical medical imaging technologies and advanced scientific research to the burgeoning fields of space exploration and, increasingly, clean energy initiatives. Its unique characteristics, including its low boiling point, inertness, and high thermal conductivity, make it irreplaceable in numerous high-tech sectors. Consequently, global demand for this noble gas has experienced a sustained and significant increase over the past decades.
The primary commercial source of helium is natural gas reservoirs, where its concentration typically remains remarkably low, often less than 1%. The conventional industrial approach to helium extraction from these reservoirs generally involves a multi-stage process. This typically begins with energy-intensive cryogenic distillation, which separates bulk components, followed by more refined purification steps utilizing pressure swing adsorption (PSA) or vacuum swing adsorption (VSA) processes. While cryogenic distillation excels at large-scale separation, adsorption processes offer a compelling and often more economically viable alternative for smaller-scale helium production, and can even be employed independently for purification purposes, presenting a less capital-intensive pathway compared to their cryogenic counterparts.
This present work delves into the feasibility and optimization of a standalone PSA process for the efficient separation of helium. Our investigation employs a detailed mathematical model of the Skarstrom cycle, a well-established PSA configuration. A key aspect of this study is the comparative analysis of two distinct and widely used adsorbent materials: zeolite 13X and activated carbon. Furthermore, we explore the process performance across two significantly different feed compositions, specifically 47% and 85% helium, allowing for a comprehensive understanding of the PSA unit's adaptability and efficacy under varying input conditions.
For each adsorbent and feed composition, the Skarstrom cycle is rigorously optimized. Our multi-objective optimization strategy aims to simultaneously maximize critical performance indicators: product purity, recovery, and productivity. Concurrently, a significant emphasis is placed on minimizing the overall energy consumption of the cycle, a crucial factor for economic viability and environmental sustainability. Beyond the foundational Skarstrom cycle, we have also considered and modeled more complex cycle configurations, such as 6-step cycles incorporating pressure equalization steps, to further enhance efficiency and performance. The results derived from these optimization studies are particularly encouraging, suggesting that both zeolite 13X and activated carbon exhibit remarkably similar performance characteristics for helium separation. Crucially, our findings indicate that it is entirely achievable to produce Grade 3 to Grade 5 helium (corresponding to purities of 99.9% to 99.999%) using a relatively simple, four-step, single-stage PSA cycle configuration, with even higher efficiencies possible with the more advanced cycles. This outcome underscores the potential of PSA technology to contribute significantly to the global helium supply chain, particularly for applications requiring high-purity helium. This research provides valuable insights into enhancing helium recovery and contributing to the strategic supply of this vital element.
The primary commercial source of helium is natural gas reservoirs, where its concentration typically remains remarkably low, often less than 1%. The conventional industrial approach to helium extraction from these reservoirs generally involves a multi-stage process. This typically begins with energy-intensive cryogenic distillation, which separates bulk components, followed by more refined purification steps utilizing pressure swing adsorption (PSA) or vacuum swing adsorption (VSA) processes. While cryogenic distillation excels at large-scale separation, adsorption processes offer a compelling and often more economically viable alternative for smaller-scale helium production, and can even be employed independently for purification purposes, presenting a less capital-intensive pathway compared to their cryogenic counterparts.
This present work delves into the feasibility and optimization of a standalone PSA process for the efficient separation of helium. Our investigation employs a detailed mathematical model of the Skarstrom cycle, a well-established PSA configuration. A key aspect of this study is the comparative analysis of two distinct and widely used adsorbent materials: zeolite 13X and activated carbon. Furthermore, we explore the process performance across two significantly different feed compositions, specifically 47% and 85% helium, allowing for a comprehensive understanding of the PSA unit's adaptability and efficacy under varying input conditions.
For each adsorbent and feed composition, the Skarstrom cycle is rigorously optimized. Our multi-objective optimization strategy aims to simultaneously maximize critical performance indicators: product purity, recovery, and productivity. Concurrently, a significant emphasis is placed on minimizing the overall energy consumption of the cycle, a crucial factor for economic viability and environmental sustainability. Beyond the foundational Skarstrom cycle, we have also considered and modeled more complex cycle configurations, such as 6-step cycles incorporating pressure equalization steps, to further enhance efficiency and performance. The results derived from these optimization studies are particularly encouraging, suggesting that both zeolite 13X and activated carbon exhibit remarkably similar performance characteristics for helium separation. Crucially, our findings indicate that it is entirely achievable to produce Grade 3 to Grade 5 helium (corresponding to purities of 99.9% to 99.999%) using a relatively simple, four-step, single-stage PSA cycle configuration, with even higher efficiencies possible with the more advanced cycles. This outcome underscores the potential of PSA technology to contribute significantly to the global helium supply chain, particularly for applications requiring high-purity helium. This research provides valuable insights into enhancing helium recovery and contributing to the strategic supply of this vital element.
