Aug 31 (Reuters) - Sinopec Corp , Asia's largest refiner, has further delayed the startup of a planned maintenance of its 100,000 barrel-per-day (bpd) Jiujiang refinery by three weeks to Sept 20, an industry source said on Wednesday.

The delay was mainly caused by slow deliveries of equipment and parts needed for the roughly one-month turnaround.

The plant, the main fuel supplier in southern Jiangxi province, was initially scheduled to start overhauling its crude distillation unit from late July, but the kickoff was postponed to late August due to slow preparations.

(Reported by Jim Bai and Chen Aizhu; Editing by Ken Wills)