Experimental investigation of LPG-releasing processes with varied damage sizes on a pressurized vessel

The presented experimental study was launched based on the LPG explosion accident near the city of Wenling, China, in June 2020. Multiple measurement methods have been coordinated in the experiments to capture different parameters. The damage size on the vessel is varied with replaceable rupture modules. The results show that the size of the damage is a decisive factor for distinguishing the outcome of the gas-releasing processes from a continuous discharging to a blowdown depressurization. The optical measurement illustrates the distributions of the released gas and indicates a much higher explosion potential of blowdown depressurization than continuous discharging. The experimental results confirm the rapid temperature drop due to the LPG-releasing, which has led to the embrittlement of the structure materials and was able to enlarge the damage size of the LPG tank. This new finding can largely increase the damage size on the tank and change the release process to blowdown depressurization. The damage escalation on the pressurized tank due to gas-release processes reveals the mechanism causing the disintegration of the tank as well as the severe explosion in the Wenling accident. According to the results, low alloy steel is not recommended for the structural material of LPG tanks.

Automated summary

The experimental study is based on the LPG explosion accident near Wenling, China in June 2020. Various measurement methods were used to capture different parameters, and the results showed that the size of damage is a crucial factor in determining the outcome of gas-releasing processes. Optical measurement revealed the distribution of released gas and demonstrated the higher explosion potential of blowdown depressurization compared to continuous discharging. The study also confirmed the rapid temperature drop caused by LPG-releasing, leading to the embrittlement of structural materials and enlargement of the damage size of the LPG tank.