PhD Thesis Defence Presentations - Charikleia Zampeta
Abstract (Περίληψη)
Overpopulation and overconsumption of products have led to wastewater increase. Wastewaters may be discharged to the aquatic ecosystems without treatment. Untreated wastewaters could cause problems in human health and eutrophication as well.
In the present study three different kinds of wastewater were treated (printing ink wastewater, table olive wastewater and cheese whey wastewater) with various physicochemical methods. The study was mainly focused on printing ink wastewater treatment due to it has not been sufficiently studied until now, even though it presents highly industrial interest. Conventional biological methods will not be studied due to the physicochemical characteristics of the wastewaters. Electrocoagulation, coagulation/flocculation, hydrodynamic cavitation and the combination of the above methods will be studied for wastewater treatment.
Initially, hydrodynamic cavitation was used to decolorize industrial-grade ink solutions and the diluted printing ink wastewater to find the operational conditions of the reactor. However, a combination with a post-treatment method was applied to maximize pollutants removal. Hence, the hydrodynamic cavitation followed by sedimentation was used, taking advantage of the intense conditions inside the hydrodynamic cavitation reactor and the colloidal suspension nature of inks.
The undiluted printing ink wastewater is difficult to be treated due to its high pollutants’ concentrations. In the present study, the undiluted printing ink wastewater, was treated initially with continuous flow electrocoagulation reactor, using aluminum electrodes. It was observed that the efficiency of the process was increased, reducing inlet flow rate and increasing current density. Another method used for printing ink wastewater treatment was the combined hydrodynamic cavitation and pH fixation method. It was deduced that the process maximized removals, while the process costs were reduced using hydrodynamic cavitation as pretreatment method. Moreover, printing ink wastewater was treated with hydrodynamic cavitation and coagulation/flocculation. Coagulant and flocculant addition led to high pollutants removal, while hydrodynamic cavitation led to the reduction of the coagulant concentration. Finally, a comparison of the above methods, in terms of pollutants removal, treatment costs, toxicity and sludge production, was made and hydrodynamic cavitation and pH fixation, was proposed as an appropriate method for highly intensively colored wastewaters.
Moreover, the agriculture wastewaters were also treated with the above methods. Pilot scale electrocoagulation was proved to be an alternative, cost-efficient, method for the treatment of biologically pre-treated table olive processing wastewater. In parallel, for the cheese whey treatment, the combination of hydrodynamic cavitation and coagulation/flocculation as a first treatment step and then the use of filter press as a past treatment step led to a non-colored transparent liquid with reduced pollutants’ concentrations.
The aim of the study was to propose an efficient, easy applicable, cost affordable as well as environmentally friendly method for the treatment of each wastewater.
Speakers Short CV (Σύντομο Βιογραφικό Ομιλητή)
Education
2018–Present:
PhD Student, Department of Chemical Engineering, University of Patras
2013 – 2018:
Integrated Master of Engineering (Meng), Department of Chemical Engineering, University of Patras, Grade: 7.35/10
Publications
Benekos, A.K., Zampeta, C., Argyriou, R., Economou, C.N., Triantaphyllidou, I.E., Tatoulis, T.I., Tekerlekopoulou, A.G., Vayenas, D.V., 2019. Treatment of table olive processing wastewaters using electrocoagulation in laboratory and pilot-scale reactors. Process Saf. Environ. Protect. 131, 38–47. https://doi.org/10.1016/j.psep.2019.08.036.
Zampeta, C., Bertaki, K., Triantaphyllidou, I., Frontistis, Z., Vayenas, D.V, 2021. Treatment of real industrial-grade dye solutions and printing ink wastewater using a novel pilot-scale hydrodynamic cavitation reactor. J. Environ. Manage. 297, 113301. https://doi.org/10.1016/j.jenvman.2021.113301.
Zampeta, C., Bertaki, K., Triantaphyllidou, I., Frontistis, Z., Koutsoukos, P.G., Vayenas, D.V., 2022a. Pilot-scale hybrid system combining hydrodynamic cavitation and sedimentation for the decolorization of industrial inks and printing ink wastewater. J. Environ. Manage. 302, 114108. https://doi.org/10.1016/j.jenvman.2021.114108.
Zampeta, C., Mastrantonaki, M., Katsaouni, N., Frontistis, Z., Koutsoukos, P.G., Vayenas, D. V., 2022b. Treatment of printing ink wastewater using a continuous flow electrocoagulation reactor. J. Environ. Manage. 314, 115033. https://doi.org/10.1016/j.jenvman.2022.115033.
Zampeta C., Arvanitaki, F., Frontistis Z., Charalampous, N., Dailianis, S., Koutsoukos, P.G., Vayenas, D. V., 2022c. Printing ink wastewater treatment using combined hydrodynamic cavitation and pH fixation. J. Environ. Manage. 317, 115404. https://doi.org/10.1016/j.jenvman.2022.115404.
Zampeta C., Paparouni, C., Tampakopoulos, A., Frontistis, Z., Charalampous, N., Dailianis, S., Koutsoukos, P.G., Paraskeva, C.A., Vayenas, D. V., 2022d. Printing Ink Wastewater Treatment Using Hydrodynamic Cavitation and Coagulants/Flocculants. J. Environ. Manage. 321, 115975. https://doi.org/10.1016/j.jenvman.2022.115975.