{"646551":{"#nid":"646551","#data":{"type":"event","title":"PhD Defense by Jinchen Chen","body":[{"value":"\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EPh.D. Thesis Defense Announcement\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EFate and Effect of Peracetic Acid Solutions on Biological Wastewater Treatment Systems\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003Eby\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EJinchen Chen\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EAdvisor(s):\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Spyros G. Pavlostathis (GT-CEE)\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ECommittee Members:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003EDr. Ching-Hua Huang (GT-CEE), Dr. Sotira Yiacoumi (GT-CEE), Dr. Xing Xie (GT-CEE), and Dr.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EYuanzhi Tang (GT-EAS)\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDate \u0026amp; Time:\u003C\/strong\u003E May 3rd, 2021 | 3-6 pm EST\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELocation: \u003C\/strong\u003E\u003Ca href=\u0022https:\/\/bluejeans.com\/878536600\u0022\u003Ehttps:\/\/bluejeans.com\/878536600\u003C\/a\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cbr \/\u003E\r\n\u003Cstrong\u003EPeracetic acid (PAA), as a wide-spectrum effective disinfectant, has been extensively and increasingly used in many\u003Cbr \/\u003E\r\nindustries, especially in poultry processing to control food-borne pathogens. Upsets of biological wastewater treatment\u003Cbr \/\u003E\r\nprocesses and failures of whole effluent toxicity (WET) tests have been reported as potentially caused by the excessive\u003Cbr \/\u003E\r\nuse of PAA solutions. However, information related to the fate and effect of PAA on biological wastewater treatment\u003Cbr \/\u003E\r\nprocesses commonly used in poultry processing plants is extremely limited. This dissertation focused on the\u003Cbr \/\u003E\r\nassessment of the fate of a PAA solution in poultry processing wastewater streams, factors contributing to PAA\u003Cbr \/\u003E\r\ndecomposition, and the evaluation of the effect of PAA on biological treatment processes, such as organic matter\u003Cbr \/\u003E\r\ndegradation, nitrification, and denitrification. On-site monitoring did not detect PAA in dissolved air flotation (DAF)\u003Cbr \/\u003E\r\ninfluent and effluent samples collected at mid plant operation shifts; however, up to 25 mg\/L PAA was detected in the\u003Cbr \/\u003E\r\nDAF effluent at the end of the operation shift coinciding with emptying chiller tanks where PAA levels in excess of\u003Cbr \/\u003E\r\n1,000 mg\/L are maintained. The PAA decomposition rate in poultry processing wastewater correlated positively with\u003Cbr \/\u003E\r\npH, temperature, wastewater strength and organic content, and negatively with initial PAA concentration. PAA\u003Cbr \/\u003E\r\ndecomposition resulted in equimolar concentrations of acetic acid. The inhibitory effect of the PAA solution on\u003Cbr \/\u003E\r\norganic matter degradation, nitrification and denitrification was dose-dependent, with significant inhibition at PAA\u0026nbsp;\u003Cbr \/\u003E\r\n40 mg\/L; fast recovery was observed after direct PAA solution addition ended. Microbial acclimation to PAA did not\u003Cbr \/\u003E\r\ntake place under aerobic conditions, but a low degree of acclimation was observed under anoxic conditions over a\u003Cbr \/\u003E\r\nlong-term operation of semi-continuously fed bioreactors. The impact on nitrification was predominantly attributed to\u003Cbr \/\u003E\r\nenzyme inhibition than to loss of nitrifiers, whereas the impact on denitrification was attributed to both enzyme\u003Cbr \/\u003E\r\ninhibition and loss of culture viability. Intracellular reactive oxygen species (ROS) were not the cause of nitrification\u003Cbr \/\u003E\r\ninhibition, but contributed to the decrease in denitrification activity. Nevertheless, the capacity of the microbial\u003Cbr \/\u003E\r\ncommunities to manage PAA-induced cell oxidative stress increased in both aerobic and anoxic reactors over the longterm\u003Cbr \/\u003E\r\noperation. Long-term evaluation of PAA on a continuously-fed, three-reactor biological nitrogen removal (BNR)\u003Cbr \/\u003E\r\nsystem showed that continuous, direct addition of PAA at 80 to 200 mg\/L in the first, anaerobic reactor did not affect\u003Cbr \/\u003E\r\nthe BNR system performance; however, organic matter degradation and nitrogen removal were severely affected by\u003Cbr \/\u003E\r\ncontinuous feeding with wastewater carrying residual PAA at 80 and 200 mg\/L. Direct addition of PAA at 3 mg\/L to a\u003Cbr \/\u003E\r\nhighly enriched nitrifying culture resulted in severe nitrification inhibition not caused by loss of cell viability or cell\u003Cbr \/\u003E\r\noxidative stress, but rather by enzyme inhibition reflected in the culture transcriptional levels. The outcome of the\u003Cbr \/\u003E\r\nstudy provides crucial information for the rational design and operation of biological treatment processes under the\u003Cbr \/\u003E\r\neffect of PAA solutions. It also provides information for the poultry processing industry to develop a sound\u003Cbr \/\u003E\r\nmethodology that will ensure the continuous use of PAA solutions to achieve pathogen-free products, while avoiding\u003Cbr \/\u003E\r\nupsets of biological processes treating PAA-bearing wastewater.\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Fate and Effect of Peracetic Acid Solutions on Biological Wastewater Treatment Systems"}],"uid":"27707","created_gmt":"2021-04-16 20:35:48","changed_gmt":"2021-04-16 20:35:48","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2021-04-23T17:20:00-04:00","event_time_end":"2021-04-23T17:20:00-04:00","event_time_end_last":"2021-04-23T17:20:00-04:00","gmt_time_start":"2021-04-23 21:20:00","gmt_time_end":"2021-04-23 21:20:00","gmt_time_end_last":"2021-04-23 21:20:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}