Study on Pores and Fractures Characteristics of Coal in Boli Basin

Abstract

In order to evaluate the pore fracture characteristics of coal in Boli Basin, this paper, by means of low temperature liquid nitrogen adsorption, mercury injection test, coal macerals and vitrinite reflectance measurement, scanning electron microscope test and hand specimen description, has studied the pore, micro fracture, endogenetic fracture and exogenetic fracture characteristics of 15 samples from three mining areas in Boli Basin. A systematic study was carried out. The results show that the macerals of coal in Boli Basin are mainly vitrinite, accounting for 80.80%-88.00%; the contents of exinite and inertinite are less; the reflectance of vitrinite is between 0.77%-1.42%; the pores of coal are mainly micro pores and small pores, and the pore types are parallel plate pores and cylinder pores; the micro fractures in coal are more developed, mainly tensile fractures; the middle end of endogenetic fractures is cut. The linear density of the cleavage is 18 strips/5 cm, the linear density of the surface cleavage is 20 strips/5 cm, and the height is 1mm-8mm; the main direction of the exogenetic fracture is NW.

Keywords

• pores and fractures characteristics
• low temperature liquid nitrogen adsorption
• mercury injection
• scanning electron microscope test
• boli basin
• cbm development