Nigeria's Dangote oil refinery could begin test runs as early as this week after receiving a sixth crude cargo on Monday, company officials said, finally bringing the 650,000 barrels per day (bpd) plant to life after years of construction delays. The refinery, funded at a cost of $20 billion by Africa's richest man, Aliko Dangote, is being built at Lekki, on the outskirts of the commercial capital Lagos. Nigeria currently imports most of its fuel but the Dangote refinery will make it self sufficient and able to export fuel to neighbours in West Africa.