Jiatong Tan, Xiaolong Li, Yuquan Jing, Shangce Ji, Wei Liu, Zong Rong
Helium is indispensable in modern industry, yet its supply remains constrained against the rising global demand. This review outlines methods for extracting helium from natural gas, including adsorption, cryogenic, and membrane separation, as well as integrated processes that combine multiple techniques. The principles, advantages, limitations, and development trends of each method are discussed. Cryogenic extraction offers high output, purity, and recovery rates but is energy intensive. Membrane separation is energy efficient but limited by membrane materials, making it difficult to achieve both high recovery and high purity. Hydrate-based methods avoid refrigeration and significant pressure drops, although techniques for rapid and stable hydrate formation are underdeveloped. Combining cryogenic, membrane, and adsorption methods based on gas composition and flow conditions can optimize the trade-offs among recovery rate, purity, and operational costs. Currently, cryogenic and membrane processes remain the dominant technologies in industrial applications.