The plant is operated by a subsidiary of China's biggest oil company, state-owned China National Petroleum Corp.
A cabinet investigation showed the explosion was caused by negligence and a failure to observe regulations on the plant's operations.
It killed eight people and forced 10,000 to flee their homes.
State media reports said Duan Wende, the vice general manager of the China National Petroleum Corp. and senior vice president of PetroChina, had received a "demerit" on his personal record.
Nine other executives, including Yu Li, board chairman and general manager of the Jilin branch of PetroChina, were either given serious warnings, demoted or dismissed, the reports said.