BANGKOK - Thailand's natural gas demand is expected to rise 10.6 percent in 2010 to 3.95 billion cubic feet per day due mainly to growing demand from petrochemical plants, PTT PTT.BK, the country's sole gas supplier, said on Monday. Domestic gas consumption in 2009 should grow by around 3.3 percent to 3.57 billion cubic feet per day, Permsak Shevawattananon, senior executive vice president for PTT's gas business, told reporters.

The main growth driver next year will come from petrochemical plants, Permsak said, adding PTT's sixth gas separation plant and an ethane plant should come onstream in early 2010 if a dispute at the country's biggest industrial estate was resolved.

A Thai court is in the process of hearing a case involving environmental health concerns at the Map Ta Phut industrial estate in the eastern province of Rayong. A verdict is expected by February.

The economic recovery should help boost demand from industrial users and for natural gas for vehicles (NGV), Permsak said.

For 2009, some 68.8 percent of natural gas was used by power producers, 16.9 percent by petrochemical plants, 10.3 percent by industrial users and the rest for NGV, the top energy firm said.

Demand for NGV this year was expected to jump 75 percent to 133 million cubic feet per day from 76 million in 2008, said PTT, whose gas business accounts for one-third of core profit. (Reporting by Khettiya Jittapong; Editing by Alan Raybould)