(593d) Pulsed-Corona High Oxidation Reactors in Gas Phase Applications: Effect of the Field Variation on Reactor Conversion

High oxidation methods based on electrical fields are a viable alternative to eliminate contaminants such as NOx, smog particles, and other detrimental contaminants present in the atmosphere. Within these types of methods, the “cold plasma” or, alternatively, pulsed-corona systems are a very attractive approach. Gas-Phase corona discharge reactors modeled in literature so far, can be classified essentially into three categories: a) Models that follow ‘continuum mechanics' approach by emphasizing the chemistry without addressing dynamics of the streamers ([1]-[5]), b) models that calculate the spatial/ temporal properties of streamers by solving governing equations of corona discharge [6]-[9] and c) ‘Ad-hoc' models that investigate gas heating, diffusion etc.[10]-[13]. Although a number of contributions can be found, much more needs to be done in order to have methodologies based on first principles of reactor analysis and design. In some of the recent contributions in the literature (see, for example, Mok et al [1]) authors introduced a formulation for pulsed corona-based reactors for the elimination of contaminants from the gaseous phase. The analysis uses a number of assumptions that are unnecessary and do not lead to the identification of other potential useful situations in the application of these types of reactors. The purpose of this contribution is to show that, by using a systematic application of transport and reaction fundamentals and scaling arguments [16-17], the engineering (or, alternatively, macroscopic) equations for the reactor can be derived without these unnecessary assumptions. Moreover, a reactor models approach will be used to identify a number of potentially interesting situations for the design of these types of reactors that capture some of the key characteristics of the reactor system. For example, “an electrode problem” and a “reactor domain problem” will be identified and used to show potential reactor behaviors and optimization approaches. Therefore, the analysis offers a framework where different reactor situations can be easily identified, pursued and compared.

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