As water scarcity intensifies across many parts of the world, including Central Asia, scientists are searching for ways to produce energy without placing additional pressure on limited freshwater resources. New research led by scientists at Nazarbayev University demonstrates that cryogenic fracturing using liquid nitrogen (LN₂) could offer a sustainable alternative to conventional hydraulic fracturing for extracting coalbed methane (CBM), a cleaner-burning transitional fuel particularly in arid regions.
The study, conducted by Sotirios Nik Longinos, Dastan Begaliyev, Mohammad Asif, and Mirlan Tuleugaliyev, investigates how LN₂ treatment alters the pore structure of coal from the Karaganda Coal Basin in Kazakhstan, one of Central Asia’s most significant energy resources. Using advanced techniques including mercury intrusion porosimetry and low-pressure nitrogen adsorption, the team shows that cryogenic treatment enhances pore connectivity, increases permeability, and improves methane recovery potential without the need for water.
Kazakhstan ranks among water-stressed countries, making waterless extraction technologies especially relevant. Unlike hydraulic fracturing, which requires large volumes of water and can raise environmental concerns, liquid nitrogen fracturing relies on rapid cooling to create thermal stress within coal seams, generating fractures that allow methane to flow more freely.
“Our findings demonstrate that liquid nitrogen can significantly modify coal pore networks, creating new pathways for methane while avoiding the environmental footprint associated with water-based fracturing,” the researchers note.
The experiments reveal that longer freezing times and repeated freezing-thawing cycles lead to measurable increases in pore volume and connectivity. Nitrogen adsorption capacity and mercury intrusion volumes were strongly correlated with treatment duration, indicating that cryogenic processes promote the formation of interconnected fracture networks.
“This approach is particularly promising for water-scarce regions where conventional hydraulic fracturing may not be viable,” the team explains.
Why it matters
Coalbed methane is considered a lower-emission alternative to coal combustion and can serve as a bridge fuel during the transition to low-carbon energy systems. Unlocking CBM resources using waterless techniques could help countries balance energy security with environmental protection.
The Karaganda Coal Basin alone holds vast methane potential, and improved recovery methods could contribute to regional energy supply while reducing methane leakage risks associated with unmanaged coal seams.
Impact statements
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Climate relevance: Improved methane recovery can reduce uncontrolled emissions from coal seams and support cleaner energy pathways.
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Water sustainability: LN₂ fracturing eliminates the need for large volumes of water, making it suitable for arid and water-stressed regions.
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Energy security: Enhanced CBM production could strengthen domestic energy supply in Kazakhstan and similar regions.
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Technology innovation: The study provides new insights into pore structure evolution under cryogenic treatment, informing next-generation extraction strategies.
Global applicability: Waterless fracturing technologies may be critical as climate change intensifies drought conditions worldwide.
Authors and affiliations
Sotirios Nik Longinos — School of Mining and Geosciences, Department of Petroleum Engineering, Nazarbayev University, Astana, Kazakhstan
Dastan Begaliyev — Industrial and Technological Institute, Zhangir Khan University, Uralsk, Kazakhstan
Mohammad Asif — Department of Geotechnical Engineering, Tongji University, Shanghai, China
Mirlan Tuleugaliyev — School of Engineering and Digital Sciences, Nazarbayev University, Astana, Kazakhstan