The 1.2 million tonne-per-year (or about 30,000 barrels per day) facility was taken offline in April after Sinopec conducted a company-wide inspection of pipelines following a deadly explosion in Qingdao late last year.

"The pipeline that supplies condensate is very old, probably more than 20 years. Bad corrosions were found," said the source with direct knowledge of the matter, who requested anonymity as he is not authorised to speak to media.

It may take a year or two to build another one, and there is no other pipeline available to replace it, the source added.

Condensate splitters process condensate, a very light crude oil, into naphtha, which is commonly used as feedstock for ethylene, a key building block for petrochemicals.

The Tianjin plant, near Beijing, operates a total of 1.2 million-tpy ethylene capacity and a 250,000-bpd refinery.

After the shutdown, Sinopec Tianjin has switched to using more domestically produced naphtha, as well as liquefied petroleum gas (LPG) to make ethylene.

It previously imported condensate from suppliers such as Australia and Iran.

(Reporting by Chen Aizhu; Editing by Anupama Dwivedi)