Hanwha Total SM tank shut after second explosion

South Korea's Hanwha Total Petrochemical was hit by a second explosion at its 400,000 t/yr styrene monomer (SM) unit in Daesan over the weekend, leading to a shutdown of the storage tank involved and a government investigation that will possibly lead to penalties against the company.

The environment ministry said that 262 area residents and plant workers were injured by the chemical discharges and were treated for nausea, eye irritation and other symptoms.

The first incident occurred on 17 May when a sudden increase in temperature caused SM and other chemicals in the tank to vaporize and be vented high into the air, spreading as far as a village four kilometers away. The second blast occurred early on 18 May as coolant was being applied to the storage facility.

The tank is being drained to prevent any further discharges, with South Korea's environment ministry planning to investigate violations of chemical safety rules. Area residents have protested outside the plant, demanding that changes be made to prevent additional accidents. The SM unit involved is shut down.

The Daesan complex was already partially shut because of a workers' union strike that prevented the company from restarting its other 700,000 t/yr SM unit after completing a 27 March-6 May turnaround. Hanwha Total declared a force majeure on 9 May because of the strike and a lack of feedstock.