The tank, at a plant of the state-owned China National Petroleum Corporation, blew up in the north-west Xinjiang region on Saturday as 24 workers were painting anti-corrosive material on it, the China Daily reported.
The blast in the city of Karamay may have been triggered by a chemical reaction from organic materials in the paint, the report said, quoting the deputy director with the local government work safety bureau.
The oil tank was part of a 10-million-ton oil refining project initiated by the state oil giant last year, and was a component of an energy co-operation project between China and Kazakhstan that was slated for completion in 2008.
Upon completion, the 100,000-cubic-meter (3.5-million cubic feet) tank would have been used to store crude oil imported via a pipeline from Kazakhstan, the report said.
Local authorities said the blast would not affect the normal operation of the China-Kazakhstan oil pipeline and have ruled out the possibility of a second explosion or serious environmental damage, the report said.

Copyright AFP (Agence France-Presse), 2006