OSLO, Oct 9 (Reuters) – Norsk Hydro has won permits from Brazilian authorities to restart half the capacity of its Alunorte alumina refinery, the world’s largest, the metals maker said in a statement on Tuesday. The company last week said it would shut the plant, as well as the related Paragominas bauxite mine amid a lingering environmental dispute that had kept the facilities operating at 50 percent of capacity since March. The decision to shut the plant, and lay off 4,700 people, was made as the company’s bauxite residue deposit was about to fill up, but Hydro late on Monday won permission to use technology that would alleviate this situation, the company said. “Alunorte is expected to be able to ramp up to 50 percent production within two weeks,” Hydro said of the plant, which at full capacity can produce some 6.4 million tonnes of alumina, or 10 percent of the world’s capacity outside China. “Hydro continues its dialog with all relevant authorities to bring Alunorte back to full production and normalize its operations in Brazil,” it added. Alunorte’s output, enough to produce more than 3 million tonnes of aluminium per year, is sold to metal plants around the world, including Hydro’s own facilities in Norway and Brazil, and the shutdowns have pushed global metal prices higher.The Albras smelter, a joint venture between Hydro and Nippon Amazon Aluminium and located next to the alumina plant, will be able to maintain aluminium output at an annual rate of 230,000 tonnes per year, half its capacity, in line with announcements first made in April.