The Influence of Coal Body Structure on Coal Fines’ Output Characteristics in the Southern Qinshui Basin

Abstract

Large amounts of coal fines are discharged from coalbed methane wellheads in the Qinshui Basin, obstructing the continuity of drainage; their extraction poses significant hazards. This paper recognized the coal body structure of 30 coalbed methane wells in the study region, using the integrated identification method of logging curve and tectonic curvature. The research found that the primary structural coal output of coal fines concentration averaged 0.237 g/L, the average content of particle size 10–100 μm was 58.88%, the average range of particle size 1–10 μm was 22.91%, and the main form was irregular columns and lumps. The average concentration of fractured structural coal fines was 1.169 g/L, the average content of particle size 10–100 μm was 41.73%, the average range of particle size 1–10 μm was 31.77%, and the main form was balls and lumps. The average concentration of granulated-mylonitic structured coal fines was 3.156 g/L, the average content of particle size 10–100 μm was 25.26%, the average range of particle size 1–10 μm was 57.59%, and the coal fines were mainly in the form of clusters and flaky aggregates.