Suppressing methane explosion overpressure using a charged water mist containing a NaCl additive

•Water mist containing NaCl additive was charged by induction charging.•Charged water mist containing NaCl additive was used to suppress methane explosion in pipeline.•The suppression effect on explosion overpressure was significantly enhanced after water mist being charged.•There exists a positive coupling effect between NaCl additive and charging effect.•The methane explosion can be effectively suppressed by charged water mist containing NaCl additive in pipeline.

To reduce the hazards caused by methane explosions in methane transport pipelines and further improve the suppression efficiency of a methane explosion, a water mist containing a NaCl additive charged by induction charging was used to inhibit a methane explosion in a small experimental pipeline. A high-frequency pressure sensor was used to record the overpressure signals. The experimental results show that the inhibition of the methane explosion overpressure using the water mist containing a NaCl additive was significantly enhanced after the water mist was charged. Compared to a water mist containing only NaCl, the peak overpressure of the methane explosion dropped by 10.579 kPa (43.43%) due to the charged water mist at a charging voltage as 8 kV when the concentration of the NaCl additive was 8%. A positive coupling function between the NaCl additive and the charging effect was identified, and the suppression efficiency of the combined action was much greater than each single action combined. Analysis shows that the coupling function between the NaCl additive and the charging effect was due to the mutual increase in the inhibition of the methane explosion overpressure.