HANOI, Jan. 19 (Xinhua) -- The 9-billion-U.S.-dollar Nghi Son oil refinery in Vietnam's central Thanh Hoa province will not test run in the first quarter of this year as scheduled due to some technical errors, local media reported on Friday.

The refinery has a design capacity of annually processing 10 million tons of crude oil.

The test run is likely to take place in the second quarter or even third quarter, Vietnamese online newspaper VietNamNet reported, adding that construction of the refinery is now 96.6 percent complete.

The refinery's investors include Vietnam's National Oil and Gas Group (PetroVietnam), a firm from Kuwait and two companies from Japan.

According to Binh Son Refining and Petrochemical Company (BSR), which manages and runs Vietnam's biggest oil refinery Dung Quat in central Quang Ngai province, the country's annual demand for petroleum products will stand at some 6.5 million tons, and for diesel around 8.5 million tons in the 2018-2022 period.

Dung Quat oil refinery, which became operational fully in 2011, has an annual capacity of 6.5 million tons of crude oil, meeting 30 percent of Vietnam's demand for petroleum products. It is expected to raise the capacity to 8.5 million tons in 2021.

BSR, a subsidiary of PetroVietnam, sold 7.8 percent of its charter capital, equivalent to 241.5 million shares during its first initial public offering on Jan. 17, Vietnam News Agency reported, noting that BSR is the largest enterprise to be equitized ever, with a value of some 3.2 billion U.S. dollars.

Under the BSR equitization plan, PetroVietnam will retain 43 percent of BSR's charter capital, while a maximum of 49 percent will be sold to strategic investors, expecting to earn nearly 1 billion U.S. dollars.

BSR's net revenue is estimated at more than 4.5 billion U.S. dollars, and its after-tax profit at over 367 million U.S. dollars in 2018.