Flue gas diffusion for integrated dry-cooling tower and stack system in power plants

Abstract

For the integrated dry-cooling tower and stack, the flue gas diffusion characteristics are of great concerns for the pollutant control and tower anticorrosion. In this work, the computational models of flue gas diffusion for the integrated dry-cooling tower and stack system are developed and experimentally validated. By means of numerical simulations, the flue gas diffusions inside and outside the dry-cooling tower are investigated and the flue gas concentrations at different heights of the inner tower shell and on the ground level are obtained. The rising height of flue gas is studied and compared with the separate stack. The total mass flow rate of cooling air and heat rejection of air-cooled heat exchanger for both the dry cooling system with and without the stack inside the dry-cooling tower are also obtained. The results show that not only the thermo-flow performances of the natural draft dry cooling system with the integrated stack can be improved, but also the air pollution alleviation can be guaranteed. At high wind speeds, the inner tower shell faces corrosion risks due to the flue gas deposition, so the anticorrosion measures for the tower should be taken.