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By Peter Murphy
CARTAGENA, Colombia, April 3 (Reuters) - Colombia's state-run oil company Ecopetrol will restart its 80,000 barrel per day (bpd) refinery in Cartagena in the first half of 2015 after expansion works and most likely in May, a senior company official said on Thursday.
The refinery's capacity will double to 165,000 barrels per day when it re-opens and it will be adapted to process the heavier crudes Colombia produces, reducing dependence on imports, said Pedro Alfonso Rosales, Ecopetrol's executive vice-president for downstream operations.
"Really we expect it to be between the end of April and May but the most certain is that in May it will be restarted," Rosales told Reuters on the sidelines of the Colombia Oil & Gas conference in the coastal city where the refinery is situated.
Cartagena's crude distillation unit was shut down last month, while the plant's cracking unit was taken off line last year. Rosales said logistics and distribution of imported fuels were the only operations now taking place at the plant, and no production.
Colombia is importing about 7,000 barrels per day of diesel and gasoline as a result of Cartagena's closure, the minister of mines and energy said on Wednesday.
Ecopetrol has increased tenders to buy fuels and has bought at least 8 cargoes of gasoline, ultra low-sulfur diesel (ULSD) and diluent naphtha, which it will receive in April and May.
Rosales said the refinery's expanded capacity would enable it to serve the domestic market more after traditionally focusing on the export market. The larger Barrancabermeja refinery currently provides most locally-consumed supplies.
"Cartagena will be more or less half for national production and half for exports ... once the refinery restarts. Until recently, it was exporting almost everything," Rosales said.
Colombia's crude production averaged just over 1 million barrels per day in 2013. It is seeking to draw more foreign investment to the sector to boost reserves. By the end of 2012, reserves were about 2.4 billion barrels.
Speakers at the conference from the public and private sectors have stressed the importance of finding new reserves more quickly as production rises in Colombia. By the end of 2012 they stood at nearly 2.4 billion barrels. Updated figures are due to be released in a few weeks. (Reporting by Peter Murphy. Editing by Andre Grenon)