The prices of crudes from Canada, South America, and Africa have jumped in recent weeks as Chinese oil import demand is rising from a decade-low, benchmark prices rally, and Middle East supply remains disrupted. The Djeno crude from Congo, one of the smaller producers in OPEC, is being offered at a premium of $20 per barrel over ICE Brent, anonymous traders told Bloomberg on Monday. That's up from a $15 a barrel premium two weeks ago, according to the traders. The prices of crudes from Canada, Brazil, and Argentina are also rising amid increased…