Location
Rolla, Missouri
Session Dates
11 Jun 1999 - 17 Jun 1999
Keywords and Phrases
Heading Face; Auxiliary Ventilation; Methane Gas; Visualization; Electrolysis of Water
Abstract
Three-dimensional airflow velocities at a heading face by a forcing or exhausting auxiliary ventilation system were measured in an actual size model gallery and in an actual mine. There were several stagnated regions near the roof comer, which might have danger of methane accumulation. Airflow velocities by an exhausting system were much smaller than that by a forcing system. The airflow and methane concentrations by a forcing, exhausting, or combined system were examined using a visualization technique by laser light in a reduced scale model. Water was used instead of air and very fine bubbles generated by electrolysis were employed as tracer. The behavior of the bubbles in water is similar to that of methane in the air. Accumulation of bubbles was observed at the roof comer of the face which corresponds to the region that the airflow stagnation was observed in the previous actual size model experiment. The optimal airflow rate through a forcing and exhaust duct and duct end locations to reduce hazard of methane accumulation were investigated for the combined system of ventilation. Experiments on methane accumulation using real methane in the air were also conducted in other reduced scale model.
Department(s)
Mining Engineering
Meeting Name
8th U.S. Mine Ventilation Symposium
Publisher
University of Missouri--Rolla
Document Version
Final Version
Document Type
Article - Conference proceedings
File Type
text
Language
English
Recommended Citation
Tomita, Shinji; Uchino, Kenichi; and Inoue, Masahiro, "Methane Concentration at Heading Faces With Auxiliary Ventilation" (1999). U.S. Mine Ventilation Symposium. 5.
https://scholarsmine.mst.edu/usmvs/8usmvs/8usmvs-theme5/5
Methane Concentration at Heading Faces With Auxiliary Ventilation
Rolla, Missouri
Three-dimensional airflow velocities at a heading face by a forcing or exhausting auxiliary ventilation system were measured in an actual size model gallery and in an actual mine. There were several stagnated regions near the roof comer, which might have danger of methane accumulation. Airflow velocities by an exhausting system were much smaller than that by a forcing system. The airflow and methane concentrations by a forcing, exhausting, or combined system were examined using a visualization technique by laser light in a reduced scale model. Water was used instead of air and very fine bubbles generated by electrolysis were employed as tracer. The behavior of the bubbles in water is similar to that of methane in the air. Accumulation of bubbles was observed at the roof comer of the face which corresponds to the region that the airflow stagnation was observed in the previous actual size model experiment. The optimal airflow rate through a forcing and exhaust duct and duct end locations to reduce hazard of methane accumulation were investigated for the combined system of ventilation. Experiments on methane accumulation using real methane in the air were also conducted in other reduced scale model.
