Brazil's Vale plans to produce 4.6 million tonnes of coal at its Moatize mine in Mozambique this year as it ramps up production to supply growing demand from Asia, a senior company official said on Thursday.

Vale began producing coal at Moatize last year, with first exports leaving Mozambique in September, and is investing heavily to increase the mine's capacity to 11 million tonnes by 2014 and to 22 million tonnes by 2017.

“Our production is still constrained by the limited capacity at the Beira port and the Sena railway line,” Ricardo Saad, a director at Vale Mozambique, told reporters.

“We have a lot of production stockpiled at the mine and we hope that when the refurbishment of the Sena line is completed, we can begin to accelerate our production capacity.”

The miner is also investing $4.5 billion to rehabilitate another railway line and the northern port of Nacala to carry coal from the mine, partially passing via Malawi.

The line will transport 30 million tonnes of coal when completed from mines operated by Vale and other producers.