PART I: Overview of the Thesis
5. CONCLUSIONS
This study confirms the effectiveness of pulsed corona discharge for the oxidation of phenolic and aromatic compounds of various types. The efficiency of the oxidation process increases with the reduced pulse repetition frequency when fast reacting compounds are treated allowing for a higher contribution of ozone in oxidation between pulses. For slow reacting refractory pollutants however, it is more beneficial to use higher pulse repetition frequencies to significantly increase the oxidation rate since the role of ozone in slow reactions occurred to be minor.
Enriching the gas phase with oxygen shows a significant increase in oxidation efficiency of the target compound due to the abundant formation of oxidants, ozone and ·OH radicals.
Subsequently, depleting oxygen in the gas phase lowers the oxidation rate as well as the oxidation efficiency. Higher initial concentration of the pollutant improves the oxidation efficiency accordingly. The improved oxidation efficiency observed in alkaline media indicates the increased ozone absorption and secondary ·OH radicals formation, both of which readily react with the dissociated phenolic moieties.
The effectiveness in oxidizing the parent compound has been shown by the extent of mineralization achieved which is mainly due to the action of non-selective ·OH radicals formed at the water surface combined with the ozone formed at higher oxygen concentrations. With decreasing oxygen concentrations, the role of ·OH radicals during oxidation substantially increases.
The rate is being controlled mostly by the discharge pulse parameters, with the mass transfer showing minimal influence on the oxidation efficiency. The oxidation of the target pollutants is brought about by the reaction of the hydroxyl radicals and atomic oxygen which are formed on the interface of the water.
The energy efficiencies achieved in PCD oxidation surpass those of ozone, which is the closest competitor of the technology or that of other AOPs where reported data is available.
This makes the process more advantageous especially with the simple configuration. The advantage of PCD equipment in terms of oxygen usage for improved oxidation reaction is that the gas is simply replenished, eliminating the need for gas transport.
The data obtained in this study give some additional knowledge that the pulsed corona discharge oxidation technique is energy and cost efficient relative to competing available technologies for plasma-based environmental applications.
References
Anpilov, A., Barkhudarov, E., Bark, Y., Zadiraka, Y., Christofi, M., Kozlov, Y., . . . Temchin, S. (2001).
Electric discharge in water as a source of UV radiation, ozone and hydrogen peroxide. Journal of Physics D: Applied Physics, 34(6), 993-999.
Beltrán, F. J., Rivas, F. J., & Gimeno, O. (2005). Comparison between photocatalytic ozonation and other oxidation processes for the removal of phenol from water. Journal of Chemical Technology and Biotechnology, 80, 973-984.
Bishop, D., Stern, G., Fleisch, M., & Marshall, L. (1968). Hydrogen peroxide catalytic oxidation of refractory organics in municipal waste waters. Industrial & Engineering Chemistry, Process Design & Development, 7(1), 110-117.
Bjerregaard, L., Madsen, A., Korsgaard, B., & Bjerregaard, P. (2006). Gonad histology and vitellogenin concentrations in brown trout (Salmo trutta) from Danish streams impacted by sewage effluent. Ecotoxicology, 15(3), 315-327.
Boev, S., & Yavorovsky, N. (1999). Electropulse water treatment: Proceedings of the 12th IEEE International Pulsed Power Conference. In C. Stallings, & H. Kirbie (Ed.), Proceedings of the 12th IEEE International Pulsed Power Conference. 1, pp. 181-184. Monterey, CA: IEEE.
Buser, H., Poiger, T., & Müller, M. (1999). Occurrence and environmental behavior of the chiral drug ibuprofen in surface waters and in wastewater. Environmental Science and Technology, 33(15), 2529-2535.
Buxton, G. V., Greenstock, C. L., Helman, W. P., & Ross, W. P. (1988). Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (·OH/·O−) in aqueous solution. Journal of Physical and Chemical Reference Data, 17, 513.
Chang, C., Ma, Y., Fang, G., Chao, A., Tsai, M., & Sung, H. (2004). Decolorizing of lignin wastewater using the photochemical UV/TiO2 process. Chemosphere, 56, 1011-1017.
Chang, J. (1991). Corona discharge processes. IEEE Transactions on Plasma Science, 19(6), 1152-1166.
Dilek, F., & Gokçay, C. (1994). Treatment of effluents from hemp-based pulp and paper industry. I.
Waste characterization and physico-chemical treatability. Water Science and Technology, 29, 161-163.
Dinelli, G., Civitano, L., & Rea, M. (1990). Industrial experiments on pulse corona simultaneous removal of NO and SO from flue gas. IEEE Transactions on Industry Applications, 26(3), 535-541.
Duguet, J., Anselme, C., Mazounie, P., & Mallevialle, J. (1990). Application of combined ozone–
hydrogen peroxide for the removal of aromatic compounds from a groundwater. Ozone:
Science & Engineering, 12(3), 281-294.
Eliasson, B., Hirth, M., & Kogelschatz, U. (1987). Ozone synthesis from oxygen in dielectric barrier discharges. J Phys. D: Appl. Phys, 20.
Esplugas, S., Bila, D., Krause, L., & Dezotti, M. (2007). Ozonation and advanced oxidation technologies to remove endocrine disrupting chemicals (EDCs) and pharmaceuticals and personal care products (PPCPs) in water effluents. Journal of Hazardous Materials, 149, 631-642.
Esplugas, S., Yue, P., & Perez, M. (1994). Degradation of 4-chlorophenol by photolytic oxidation.
Water Research, 28, 1323-1328.
FIMEA. (2012). Drug consumption in 2009 - 2012. Retrieved March 21, 2013, from http://raportit.nam.fi/raportit/kulutus/laakekulutus_e.pdf
Gallagher, M., Nuckols, J., Stallones, L., & Savitzl, D. (1998). Exposure to Trihalomethanes and Adverse Pregnancy Outcomes. Epidemiology, 9(5), 484-489.
Glaze, W., & Kang, J.-W. (1988). Advanced oxidation processes for treating groundwater contaminated with TCE and PCE: Laboratory studies. Journal (American Water Works Association), 80(5), 57-63.
Glaze, W., Kang, J.-W., & Chapin, D. (1987). The chemistry of water treatment processes involving ozone, hydrogen peroxide and ultraviolet radiation. Ozone Science & Engineering, 9, 335-352.
Goldstone, J., Pullin, M., Bertilsson, S., & Voelker, B. (2002). Reactions of hydroxyl radical with humic substances: bleaching, mineralization, and production of bioavailable carbon substrates.
Environmental Science & Technology, 36(3), 364-372.
Gooselink, R., van Dam, J., de Wild, P., Huijgen, W., Bridgwater, T., Nowakowski, D., . . . Sanders, J.
(2011). Valorisation of lignin - Achievements of the LignoValue project. Stockholm, Sweden:
Proceedings of the 3rd Nordic Wood Biorefinery Conference.
Gottschalk, C., Libra, J., & Saupe, A. (2000). Ozonation of water and wastewater: a practical guide to understanding ozone and its application. Weinheim: Wiley-VCH.
Hoeben, W., van Veldhuizen, E., Rutgers, W., Cramers, C., & Kroesen, G. (2000). The degradation of aqueous phenol solutions by pulsed positive corona discharges. Plasma Sources Science and Technology, 9(3), 361-369.
Hoigné, J., & Bader, H. (1976). The role of hydroxyl radical reaction in ozonation processes in aqueous solution. Water Research, 10(5), 377-386.
Hoigné, J., & Bader, H. (1983a). Rate constants of reactions of ozone with organic and inorganic compounds in water - I. Non-dissociating organic compounds. Water Research, 17, 173-183.
Hoigné, J., & Bader, H. (1983b). Rate constants of reactions of ozone with organic and inorganic compounds in water - II. Dissociating organic compounds. Water Research, 17, 185-194.
Huang, C., & Sedlak, D. (2001). Analysis of estrogenic hormones in municipal wastewater effluent and surface water using enzyme-linked immunosorbent assay and gas chromatography/tandem mass spectrometry. Environmental Toxicology and Chemistry, 20(1), 133-139.
Kavanagh, R., Balch, G., Kiparissis, Y., Niimi, A., Sherry, J., Tinson, C., & Metcalfe, C. (2004). Endocrine disruption and altered gonadal development in white perch (Morone americana) from the lower Great Lakes region. Environmental Health Perspectives, 112(8), 898-902.
Klavarioti, M., Mantzavinos, D., & Kassinos, D. (2009). Removal of residual pharmaceuticals from aqueous systems by advanced oxidation processes. Environment International, 35, 402-417.
Kogelschatz, U., Eliasson, B., & Egli, W. (1997). Dielectric-barrier discharges. Principle and Applications. Journal of Physics IV France, C4-47 - C4-66.
Kornev, I., Osokin, G., Galanov, A., Yavorovsky, N., & Preis, S. (2012). Formation of nitrite- and nitrate-ions in aqueous solutions treated with pulsed electric discharges. Ozone Science &
Engineering, 35(1), 22-30.
Kornev, J. (2003, July). Electric discharge treatment of water containing organic substances.
Proceedings on the 7th Korea-Russia International Symposium, KORUS 2003. (pp. 243-247).
Ulsan: Science and Technology.
Liney, K., Hagger, J., Tyler, C., Depledge, T., Galloway, T., & Jobling, S. (2006). Health effects in fish of long-term exposure to effluents from wastewater treatment works. Environmental Health Perspectives, 114(S-1), 81-89.
Lukes, P., Clupek, M., Sunka, P., Peterka, F., Sano, T., Negishi, N., . . . Takeuchi, K. (2005). Degradation of phenol by underwater pulsed corona discharge in combination with TiO2 photocatalysis.
Research on Chemical Intermediates, 31(4-6), 285-294.
Marusawa, H., Ichikawa, K., Narita, N., Murakami, H., Ito, K., & Tezuka, T. (2002). Hydroxyl radical as a strong electrophilic species. Bioorganic and Medicinal Chemistry, 10(7), 2283-2290.
Milne, L., Stewart, I., & Bremner, D. (2013). Comparison of hydroxyl radical formation in aqueous solutions at different ultrasound frequencies and powers using the salicylic acid dosimeter.
Ultrasonics Sonochemistry, 20(3), 984-989.
Oda, T. (2003). Non-thermal plasma processing for environmental protection: decomposition of dilute VOCs in air. Journal of Electrostatics, 57, 293-311.
Ono, R., & Oda, T. (2000). Measurement of hydroxyl radicals in an atmospheric pressure discharge plasma by using laser-induced fluorescence. IEEE Trans. Ind. Appl., 36(1), 82-86.
Ono, R., & Oda, T. (2003). Dynamics of Ozone and OH Radicals Generated by Pulsed corona discharge in humid-air flow reactor measured by laser spectroscopy. Journal of Applied Physics, 93(10), 5876-5882.
Paillard, H., Brunet, R., & Dore, M. (1988). Optimal conditions for applying an ozone-hydrogen peroxide oxidizing system. Water Research, 22(1), 91-103.
Peyton, G., & Glaze, W. (1988). Destruction of pollutants in water with ozone in combination with ultraviolet radiation. 3. Photolysis of aqueous ozone. Environmental Science and Technology, 22(7), 761-767.
Pignatello, J. (1992). Dark and photoassisted Fe3+-catalysed degradation of chlorophenoxy herbicides by hydrogen peroxide. Environmental Science & Technology, 26, 944-951.
Pokryvailo, A., Wolf, M., Yankelevich, Y., Wald, S., Grabowski, L., van Veldhuizen, E., . . . Welleman, A.
(2006). High-power pulsed corona for treatment of pollutants in heterogeneous media. IEEE Transactions on Plasma Science, 34(5), 1731-1743.
Roland, U., Holzer, F., & Kopinke, F. (2002). Improved oxidation of air pollutants in a non-thermal plasma. Catalysis Today, 73(3-4), 315-323.
Rosocha, L., Anderson, G., Bechtold, L., Coogan, J., Heck, H., Kang, M., . . . Wantuck, P. (1993).
Treatment of hazardous organic wastes using silent discharge plasmas. In B. Penetrante, & S.
Schultheis (Eds.), Non-thermal plasma techniques for pollution control (pp. 281-308). New York: Springer-Verlag.
Ryazanova, N., & Ryazanov, N. (2004). Patent No. US6802981 B2. United States of America.
Sedlak, D., & Andren, A. (1991). Oxidation of chlorobenzene with Fenton’s Reagent. Environmental Science & Technology, 25(4), 777-782.
Shin, D., Park, C., & Hahn, J. (2000). Methane conversion in pulsed corona discharge reactors. Bulletin of the Korean Chemical Society, 21(2), 228-232.
Staehelin, J., & Hoigné, J. (1982). Decomposition of ozone in water: Rate of initiation by hydroxide ions and hydrogen peroxide. Environmental Science and Technology, 16, 676-681.
Staehelin, J., & Hoigné, J. (1985). Decomposition of ozone in water in the presence of organic solutes acting as promoters and inhibitors of radical chain reactions. Environmental Science &
Technology, 19, 1206-1213.
Sun, B., Sato, M., & Clements, J. S. (1999). Use of a pulsed high-voltage discharge for removal of organic compounds in aqueous solution. Journal of Physics D: Applied Physics, 32, 1908-1915.
Ternes, T. (1998). Occurrence of drugs in German sewage treatment plants and rivers. Water Research, 32, 3245-60.
Tochikubo, F., Uchida, S., & Watanabe, T. (2004). Study on decay characteristics of OH radical density in pulsed discharge in Ar/H2O. Japanese Journal of Applied Physics, 43(1), 315-320.
Tomizawa, S., & Tezuka, M. (2007). Kinetics and mechanism of the organic degradation in aqueous solution irradiated with gaseous plasma. Plasma Chemistry and Plasma Processing, 27(4), 486-495.
Trancart, J. (1990). Treatment of triazines in water-works: efficiency of O3/H2O2 coupling. Ozone News, 18, 7-8.
Urashima, K., Chang, J., & Ito , T. (1997). Reduction of NO from combustion flue gases by superimposed barrier discharge plasma reactors. IEEE Trans. Indust. Appl., 33, 879-886.
van Veldhuizen, E., & Rutgers, W. (n.d.). Retrieved May 14, 2012, from http://www.phys.tue.nl/FLTPD/invited/veldhuizen.pdf
von Gunten, U. (2003). Ozonation of drinking water: Part I. Oxidation kinetics and product formation.
Water Research, 37(7), 1443-1467.
von Sonntag, C., & von Gunten, U. (2012). Chemistry of Ozone in Water and Wastewater Treatment:
From Basic Principles to Applications. London: IWA Publishing.
Wu, Y. (2009). Comparing Pollution by Asian Giants: China vs India. Retrieved August 17, 2013, from http://www.eai.nus.edu.sg/BB434.pdf
Vulliet, E., Cren-Olivé, C., & Grenier-Loustalot, M. (2011). Occurrence of pharmaceuticals and hormones in drinking water treated from surface waters. Environmental Chemistry Letters, 9, 103-114.
Yavorovsky, N., Peltsman, S., & Radionov, I. (2000). Patent No. 99100758. Russia.