Wind of change in ESP technology4 July 2023
Mitsubishi Heavy Industries Power Environmental Solutions, Ltd, part of Mitsubishi Heavy Industries (MHI) Group, has developed what it describes as a “revolutionary new type of electrostatic precipitator”, which it calls the “Ionic Wind Type Electrode ESP.” It employs an entirely new dust collection principle and electrode configuration, the company says, noting that ESPs are one of the company’s mainstay products.
Compared with a conventional ESP, this new design is expected to provide considerably improved performance, while also being more compact, lower cost, and promising shorter installation time.
In conventional ESPs, including competing products, when the ionic wind that flows from the discharge electrodes to the collecting electrodes strikes the collecting electrode plate, a backflow occurs that hinders the dust collection efficiency, Mitsubishi says. The performance of an ESP is evaluated, and its size determined, taking into consideration the re-entrainment of the collected dust resulting from this “backflow of ionic wind”, the company notes.
The ESP design developed by Mitsubishi Heavy Industries Power Environmental Solutions uses a combination of novel non-plate-type collecting electrode with openings combined with an optimal discharge electrode that inhibits the occurrence of backflow of ionic wind, resulting in a significant improvement in dust collection efficiency.
Development of this new system began seven years ago, with its performance and durability verified by two years of demonstration operation in an actual plant environment.
The significant improvement in dust collection efficiency enables this new type of ESP to be more compact than conventional systems, allowing it to be installed within confined spaces where installation of conventional units would be difficult. The casings of existing conventional ESPs can also be used as is, says Mitsubishi, allowing replacement of some or all of the existing internal electrodes with Ionic Wind type electrodes, resulting in improved performance (reduction in outlet dust concentration). In cases where improvement in ESP performance is not required, only a proportion of degraded conventional electrodes need to be replaced with the Ionic Wind type to achieve a comparable performance level, reducing costs and project duration.