A preliminary study of the application of Background Oriented Schlieren (BOS) for the qualitative imaging of methane emissions from coal

Abstract

Methane presents a pervasive risk in most coal mines, its dilution being one of the primary objectives of the ventilation system. Although many different types of detectors and techniques exist for quantifying methane, little is known about the qualitative aspects of methane, such as visualising how this gas flows from coal. Background Oriented Schlieren (BOS) provides a potential method from qualitative analysis of methane emissions. BOS is an imaging technique designed to visualise normally invisible flows in transparent media. This paper is a preliminary investigation of the feasibility of using the BOS technique for imaging methane release from coal.