An experimental facility to generate green hydrogen through the use of an electrolyser from solar energy was setup in Gangneung, South Korea. On 23rd May 2019 the Hydrogen Storage tank exploded resulting in multiple fatalities and injuries.
Date
Location
Industry
Substance
Cause
Multiple causes were identified:
– A malfunctioning separation membrane in the electrolyser allowed oxygen to diffuse into the Hydrogen stream contaminating it with upto 6% Oxygen.
– Membrane malfunction was exacerbated by the Electrolyser operating below its minimum power levels due to variable output of the solar panels.
– A static spark combined with the presence of oxygen in the Hydrogen stream resulted in the explosion.
Additional factors that also played a part included:
– Design Deficiencies: System lacked oxygen removal and static spark prevention mechanism in the storage tank. Potentially due to cost.
– Operator Error: Operators ignored the oxygen detectors indicating Oxygen levels had risen above 3%.
– Management Failures: Failure to adhere to the requirement of daily testing of the hydrogen stream quality.
Consequence
– Destroyed the centre’s 5,100m2 building.
– Damaged the windows and structures of neighbouring buildings within 100m.
– Two people died.
– Six others were injured.
– Explosion was heard in the city 7km away from the site.
Injuries
6
Fatalities
2
Lessons Learned
The following lessons were learnt on the aftermath of the incident:
– Important to ensure design is properly reviewed and scrutinised for safety and cost cutting measures not implemented in lieu of safety.
– Operator training on alarm response is critical.
– Ensuring that operational requirements for testing is regularly monitored and audited to ensure adherence to procedures.
Analysis
The experimental facility consisted of:
– Three buffer tanks, each with a capacity of 40 m3.
– One Tank Pressurised at 12bar, other two at 7 bar.
– 200kW alkaline electrolyser with a production capacity of 40 m3/hr of Hydrogen at 12bar.