JOHANNESBURG (Reuters) - South Africa's Kumba Iron Ore said on Tuesday it expects full-year earnings to rise by as much as 20 percent, lifted by higher prices. Kumba, a unit of Anglo American's, reported headline earnings per share of 37.97 rand for the year to end December 2012. Headline EPS, the main measure of profit in South Africa, excludes certain one-time items. "The increase in earnings is largely attributable to an increase in export iron ore prices and a weaker exchange rate, partially offset by lower production from Sishen mine during the period," the company said in a statement. Kumba's flagship Sishen mine in the remote Northern Cape province is grappling with operational problems and the company plans to restore production at the mine to full capacity of 37 million tonnes per annum by 2016. Kumba's peformance stands in contrast to that of other Anglo units in South Africa, notably Anglo American Platinum, the world's top producer of the precious metal, which fell into a loss last year and is struggling to find a turnaround strategy.