화학공학소재연구정보센터
Energy & Fuels, Vol.34, No.1, 645-654, 2020
Capture and Mitigation of Fugitive Methane: Examining the Characteristics of Methane Explosions in an Explosion Chamber Connected to a Venting Duct
Global warming and the subsequent climate change have become worldwide environmental and anthropogenic concerns. Methane and CO2 are the most potent of the greenhouse gases (GHGs), and one of the most promising methods of methane abatement is for methane to be captured through thermal decomposition processes. However, this approach introduces a major safety concern related to methane explosions and flame propagation in coal mines. It is vital that all of the safety issues related to this approach are addressed prior to the implementation of GHG emission control. This study investigates the effectiveness of venting in the event of methane explosions. In addition, the study examines the scaling effects by integrating the experimental results from this study with the data from previous explosion experiments carried out in a smaller scale experimental apparatus. The experimental setup consisted of a 1 m(3) explosion chamber connected to a 9.7 m long venting duct. The results indicated that the methane explosion pressure significantly decreased in the venting duct, which, in turn, reduced the deflagration index (class of explosion). The venting approach can reduce the explosion pressure by approximately 83%. The data for the flame propagation inside the venting duct demonstrated the presence of flame acceleration and deceleration patterns at approximately one-third (3.2 m), and at the end of the venting duct, these flame accelerations (second explosion) have not been observed when using a 20 L explosion chamber with a similar venting ratio under identical ignition energies and methane concentrations. The flame front velocity reaching the end of the venting duct was measured at approximately 52 m s(-1).