PetroChina North China Oilfield has made a breakthrough in high-rank coalbed methane (CBM) extraction technology, solving key challenges in developing the resource.

High-rank CBM is abundant in China but difficult to extract due to dense, impermeable coal formations. The research team developed three key technologies addressing well placement, reservoir stimulation and revival of mature fields.

The technologies include precision sweet-spot identification, optimized fracturing to create artificial fracture networks, and well-pattern restructuring for pressure management.

From 2018 to 2023, the technologies were applied to 398 wells across multiple blocks in the Qinshui Basin, adding 1.55 billion cubic meters of new capacity. This directly supported North China Oilfield's annual CBM production capacity reaching 2 billion cubic meters, making it China's largest medium-to-shallow CBM field.

The company is now scaling up the technologies for wider application to boost clean energy supply and energy security.