AOT board chairman Sita Divari said the clean-up operation should be completed by Wednesday. As the runway is open only to small aircraft, about 35 flights had been delayed on Monday morning.
He added that Don Mueang and U-Tapao airports have been selected as back-up airports in a bid to facilitate passengers.
An Airbus 330-300 operated by Thai Airways International skidded off the runway at Bangkok's main international airport after the nose wheel collapsed on landing late Sunday night.
The flight from Guangzhou, China, was carrying 288 passengers and 14 crew members. Passengers were evacuated using emergency slides and the 14 injured were sent to a Bangkok hospital.
The incident came after another accident involving a Thai Airways plane late last month when about 20 passengers and a cabin attendant on a THAI A-380 flight to Hong Kong were injured during strong turbulence.