Water recovery efficiency improvement using the enhanced structure of the mist eliminator

Thermal power plants are users of high water consumption, and the water consumption of cooling towers accounts for more than half of the total water consumption of the whole plant. Therefore, water saving of cooling towers is the key to water saving in thermal power plants. Wave-plate demister as a component of cooling tower influences the performance of entire system. Demister realizes the collection of liquid droplets with the penalty of extra pressure loss. Curved bends and drainage hooks are proposed as enhancing structures of demister to increase separation efficiency and reducing pressure loss simultaneously. Computational result shows that interaction between curved bend and hooks improves the overall performance of demister. Moreover, effect of enhancing parameters on the performance is presented, specifically, Euler number and separation efficiency are correlated as functions of curved bend radius and hook length. Most importantly, an experiment is conducted on a real cooling tower. It shows that the overall thermal capacity is lowered with the presence of demister. Pressure drop, separation efficiency and heat transfer of the entire system are tested with and without demisters, based on which a new criterion is proposed to evaluate the influence of demister on the overall performance of cooling tower in terms of thermal efficiency and droplets collection. Performance indexes as functions of enhancing parameters and droplets dynamic are plotted. Therefore, a quick design of demister can be realized in achieving an optimal performance of cooling tower. (c) 2021 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Automated summary

Thermal power plants heavily rely on water consumption, with cooling towers accounting for a significant portion. The design and enhancement of demisters within cooling towers play a crucial role in improving overall system performance. By optimizing demister structures, such as curved bends and drainage hooks, separation efficiency can be increased while reducing pressure loss, leading to higher thermal efficiency in the cooling tower system.