Dissertation
ATMOSPHERIC PRESSURE COLD PLASMA PROCESSING OF BIOCHAR AND INACTIVATION OF BACTERIA
Doctor of Philosophy (PhD), Washington State University
01/2019
Handle:
https://hdl.handle.net/2376/16799
Abstract
This dissertation describes my experimental investigations of an atmospheric pressure cold plasma reactor based on the corona discharge. Chapter 1 contains a literature review focused on methods used by others to produce atmospheric pressure cold plasma. This chapter includes a description of the corona discharge which is essential for my plasma reactor. Chapter 2 describes how this corona-based reactor was used to etch biochar. I investigated processing of biochar granules with admixtures of dry air and helium and demonstrated that reactive oxygen and nitrogen species were generated in the plasma discharge and that they etched biochar granules. Chapter 3 contains details regarding my investigation of the reactor with voltage and current oscillograms augmented by a unique sensor called a needle probe. I developed this needle probe so that it could provide information regarding which electrode launched a steamer when both electrodes were known to be sources of streamers. Chapter 4 involves inactivation of bacteria inoculated onto substrates consisting of biochar, stainless steel, and polyvinyl chloride. In this work the bacteria inactivation efficacy was substantially smaller on biochar substrates presumably due to the presence of lumens that provided harborage for bacteria. For the work described in Chapters 2-4, plasma was generated with a multipoint-to-multipoint electrode geometry with corona streamers originating near both electrodes. Chapter 5 presents conclusions and future work where suggestions are made for increasing the downstream flux of reactive oxygen and nitrogen chemical species that are used for plasma processing in this reactor.
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Details
- Title
- ATMOSPHERIC PRESSURE COLD PLASMA PROCESSING OF BIOCHAR AND INACTIVATION OF BACTERIA
- Creators
- Shuzheng Xie
- Contributors
- Patrick D Pedrow (Advisor)Karl R Englund (Committee Member)John B Schneider (Committee Member)Mohamed A Osman (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- School of Electrical Engineering and Computer Science
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Number of pages
- 155
- Identifiers
- 99900581616401842
- Language
- English
- Resource Type
- Dissertation