Hydraulic Model Study for AES Meghnaghat 450MW Combined Cycle Power Plant


Location

Down stream of the Meghna Bridge at Meghna Ferryghat

 

Type of Project

Thermal plume and morphological modelling

 

Period of Study

August 2000 to May 2001

 

Client

Hyundai Engineering and Construction Co. Ltd.



Description

A 450 MW Combined Cycle Power Plant (CCPP) is under construction on the right bank of the Meghna River near Meghna Bridge at Meghna Ferryghat. The area is influenced by tidal action, which is significant during the dry season. The CCPP would draw cool water from the river and discharge the hot water into the river. Inappropriate location of intake and outlet of water can create condition that would cause tremendous loss of efficiency particularly in the dry season and also endanger the aquatic life. The guidelines of the World Bank require that: " the effluent should result in a temperature increase of no more than 3 degrees Celsius at the edge of the Zone where initial mixing and dilution takes place. Where the zone is not defined, use 100 metres from the point of discharge when there are no sensitive aquatic ecosystems within this distance."

The hydraulic model study, which has been carried out by DHI (Danish Hydraulic Institute)/(Surface Water Modelling Centre) SWMC, aims at river hydraulics, advection-dispersion of heated water and sediment transport, and scouring along the proposed location of the plant using advanced mathematical tools, eg. MIKE 11, MIKE 21 and MIKE 3, developed by Danish Hydraulic Institute (DHI). Following three scenarios were investigated for the critical condition that may occur with respect to re-circulation and absolute temperature of intake with the help of a suite of one or more of the above models.

  • Discharge via canal 1 km downstream of intake
  • Submerged discharge via 100m pipe (Ø 3000) from site boundary
  • Submerged discharge via 150m pipe (Ø 3000) from site boundary