The Curacao KAE-LT-MED and auxiliary steam turbine project: A model for dual purpose MSF plants replacement

Abstract

KAE, the water and power company of Curacao, has contracted to replace its older and less efficient MSF plants with a 10,000 m 3/day Low Temperature, Horizontal Tube, Falling Film, Multi Effect Distillation (LT-MED) plant. The plant operates at a top brine temperature of 70 degrees C and requires steam at only 0.34 bar a. However, motive steam is available, as extraction from the power station's turbines, at 2.55 bar a, 155 °C, as required by the higher temperature MSF plant. This excess pressure potential is used to generate 3.1 MW of power in an auxiliary low pressure steam turbo-generator, thereby improving overall economy and lowering desalted water cost to a level unequalled by any other system. The paper describes the power station turbine, auxiliary low pressure turbo generator and LT-MED plant combined scheme, its operational features and economics.