An industry source said that PetroChina will further delay the startup of a planned maintenance of its 200,000 barrel-per-day Dushanzi refinery by two to three weeks to late August.

PetroChina had initially planned to shut down the largest refinery in northwestern Xinjiang in June or July, but it postponed the 50-day overhaul to begin in early August, as its 210,000-bpd Lanzhou refinery in neighbouring Gansu province started a partial turnaround from June 20.

Dushanzi, processing mainly Kazakhstan crude oil, was fully commissioned in September 2009 after replacing several old crude oil units with a new 200,000-bpd unit and adding a 1-million-tonne-per-year ethylene cracking unit.