Characterization of Heavy Metal Contaminated Wastewater Using a Coaxial Sensor and Electromagnetic Wave Reflection Technique

Abstract:

Industrial wastewater control is an important issue for protection of the environment. Liquid characterization using radio frequency signal is an interesting approach for selective detection of heavy metal contaminants in industrial wastewater. A simple sensor based on open-ended coaxial structure filled with the liquid under test is proposed. Liquid samples for the experiments are copper, zinc and nickel solutions with various concentrations of 1, 10, 100 and 1000 mg/liter each. From the measurement results using a vector network analyzer (VNA) in combination with the proposed sensor, the concentration of a specific contaminant can be determined by the magnitude of the measured reflection coefficient in a frequency range lower than 2 GHz. Applying a capacitive model of the sensor, complex permittivity of the liquid under test can be calculated from the measured reflection coefficient. Obvious relationship between the imaginary part of complex permittivity and the concentration of contaminant in a frequency range lower than 2 GHz was observed. The type of contaminants in the liquid samples can be identified by the position of the resonant peaks when the magnitude of reflection coefficient is plotted in the spectrum. The frequency range for contaminant’s identification lies between 2 and 3 GHz.

• Periodical: Applied Mechanics and Materials (Volumes 548-549)
• Pages: 678-682
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.548-549.678
• Online since: April 2014
• Authors: N. Puangngernmak*, S. Chalermwisutkul
• Keywords: Dielectric Property, Liquid Characterization, Reflection Technique, Wastewater

References

[1] M.U. Afsar, J.R. Birch, R.N. Clarke and G.W. Chantry, (1986). The Measurement of the Properties of Material, Proceedings of the IEEE, 74, 183-199.

DOI: 10.1109/proc.1986.13432

[2] G. Banhegyi, (1994). Dielectric spectroscopy, in Characterization of Composite Materials, Chapter, H. Ishida, Ed., Butterworth-Heinemann, Boston.

[3] S. Ramo, J.R. Whinnery and T. Van Duzer (1994). Field and Waves in Communication Electronics, 3rd Edition, John Wiley & Sons, Inc., New York.

[4] J. Krupka (2006). Frequency Domain Complex Permittivity Measuring at Microwave Frequencies, Measurement Science and Technology. Vol. 17, 55-70.

[5] L.F. Chen, C.K. Ong, C.P. Neo, V.V. Varadan and V.K. Varadan (2004), Overview of the Microwave for Characterization of Electromagnetic Material, in Microwave Electronics Measurement and Material Characterization, John Wiley & Sons, Ltd.

DOI: 10.1002/0470020466

[6] S.S.M. Hassan (1976). Ion-Selective Electrodes in Organic Functional Group Analysis. Microdetermination of Nitrates and Nitramines with Use of the Iodide Electrode., Talanta. Vol. 23, 738-740.

DOI: 10.1016/0039-9140(76)80077-x

[7] T. Kjaer, L. Hauer Larsen and N.P. Revsbech (1999). Sensitivity Control of Ion-Selective Biosensors by Electrophoretically Mediated Analysis Transport, Analytica Chimica. Vol. 391, 57-63.

DOI: 10.1016/s0003-2670(99)00231-7

[8] T. A. Bendikov and T.C. Harmon (2005). A Sensitive Nitrate Ion-Selective Electrode from a Pencil Lead. An Analytical Laboratory experiment, Journal of Chemical Education. Vol. 82, 439-441.

DOI: 10.1021/ed082p439

[9] D. Berube, F. M. Ghannouchi and P. Savard (1996).