TY - JOUR
TI - Effect of liquid nitrogen pre-treatment on the fracture behaviour of shale
AU - Su Shan-Jie
AU - Wang Sheng-Cheng
AU - Cai Feng
AU - Zhou Chun-Bo
AU - Du Meng-Lin
AU - Ren Yong-Jie
AU - Jiang Xuan
JN - Thermal Science
PY - 2025
VL - 29
IS - 2
SP - 1389
EP - 1394
PT - Article
AB - Liquid nitrogen enhancement has been successfully applied in petroleum  extraction engineering. In order to explore its feasibility in shale gas  production, the three-point bending experiments of shale were conducted  before and after liquid nitrogen treatment in this paper. The results showed  that the fracture toughness of shale decreased by about 18.8%, the wave  velocity decreased by about 6%, and CT scans showed transgranular fracture  occurring inside the shale. After destruction, the tortuosity of crack path  significantly increases, and the fracture area increases, but applied energy  demand reduced by 35%. It can be seen that the application of liquid  nitrogen in shale reservoir transformation is beneficial for increasing the  fracture volume of the reservoir, increasing the complexity of the fracture  network, and reducing the design parameter requirements of fracturing  equipment, thus saving costs.