BHP Billiton Ltd. (BHP.AU) said Wednesday coking coal prices should be supported by the lead times involved in bringing back on idled capacity.

China has recently emerged as an importer of coking coal, filling the demand gap caused by a global slowdown in buying by traditional customers, and this has in part been driven by the closure of domestic Chinese mines.

In a slide from a presentation to be delivered to analysts, BHP said the lead time for idled restarts should restrict coking coal supply and support prices.

BHP said Chinese steel mills are building bigger blast furnaces to improve productivity and that these would require better quality coke and therefore more high quality hard coking coal.

BHP, together with joint venture partner Mitsubishi Corp. (8058.TO), is the world's biggest producer of coking coal for the seaborne market.

The miner said it expects global steel demand to double over the next 15 years and that China will remain a major opportunity for iron ore while coking coal demand growth will come from both India and China.

The world is set to be short on copper in the medium to long term, BHP said, and while scrap will gain market share, import demand for copper concentrate and cathode is set to grow.

Similarly, BHP said it believes the world will be short on energy in the medium to long term, with demand being driven by emerging market growth.

-By Alex Wilson, Dow Jones Newswires; 61-3-9292-2094; alex.wilson@dowjones.com