Share This Article:

Electromagnetic and Optical Methods for Measurements of Salt Concentration of Water

Abstract Full-Text HTML Download Download as PDF (Size:1839KB) PP. 130-139
DOI: 10.4236/jemaa.2014.66013    3,656 Downloads   4,751 Views   Citations

ABSTRACT

Sensors for monitoring the salinity of water are useful tools in both environmental sciences and chemical engineering. Sensors based on a large variety of principles have been developed. Here we describe the design and testing of two different, noninvasive measurement methods for monitoring the salt concentration of water. The first method is based measurements of the refractive index using a folded-path optical refractometer, while the second utilizes an electromagnetic resonator, consisting of a magnetic coil and a capacitor, which is brought to resonance by an external magnetic field source. It is demonstrated that the folded-path optical refractometer allows one to monitor changes in salt concentration down to 1 mM in the range between 0 and 0.7 M, whereas the electromagnetic resonator has the capability of monitoring concentration changes as small as 0.3 mM over the more limited range between 0 and 5 mM.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Tengesdal, Ø. , Hauge, B. and Helseth, L. (2014) Electromagnetic and Optical Methods for Measurements of Salt Concentration of Water. Journal of Electromagnetic Analysis and Applications, 6, 130-139. doi: 10.4236/jemaa.2014.66013.

References

[1] Moreels, E., de Greef, C. and Finsy, R. (1984) Laser Light Refractometer. Applied Optics, 23, 3010.
http://dx.doi.org/10.1364/AO.23.003010
[2] Grosso, P., Le Menn, M., de Bogrenet de la Tocnaye, J.L., Wu, Z.Y. and Malarde, D. (2010) Practical versus Absolute Salinity Measurements: New Advances in High Performance Seawater Salinity Sensors. Deep Sea Research I, 57, 151.
http://dx.doi.org/10.1016/j.dsr.2009.10.001
[3] Zhao, Y., Zhang, B. and Liao, Y. (2003) Experimental Research and Analysis of Salinity Measurement Based on Optical Techniques. Sensors and Actuators B, 92, 331.
http://dx.doi.org/10.1016/S0925-4005(03)00292-2
[4] Ogura, N. and Hanya, T. (1966) Nature of Ultra-Violet Absorption of Sea Water. Nature, 212, 758.
http://dx.doi.org/10.1038/212758a0
[5] Di Noto, V. and Mecozzi, M., (1997) Determination of Seawater Salinity by Ultraviolet Spectroscopic Measurements. Applied Spectroscopy, 51, 1294.
http://www.opticsinfobase.org/as/abstract.cfm?URI=as-51-9-1294
http://dx.doi.org/10.1366/0003702971942295
[6] Pegau, W.S., Gray, D. and Zaneveld, J.R.V. (1997) Absorption and Attenuation of Visible and Near-Infrared Light in Water: Dependence on Temperature and Salinity. Applied Optics, 36, 6035.
http://dx.doi.org/10.1364/AO.36.006035
[7] Esteban, O., Navarrete, M.C., Gonzales-Cano, A. and Bernabeu, E. (1999) Measurement of the Degree of Salinity of Water with a Fiber-Optic Sensor. Applied Optics, 38, 5267.
http://dx.doi.org/10.1364/AO.38.005267
[8] Diaz-Herrera, N., Esteban, O., Navarrete, M.C. and Le Haitre, M. (2006) In Situ Salinity Measurements in Seawater with a Fibre-Optic Probe. Measurement Science and Technology, 17, 2227.
http://dx.doi.org/10.1088/0957-0233/17/8/024
[9] Gentleman, D.J. and Booksh, K.S. (2004) Determining Salinity Using a Multimode Fiber Optic Surface Plasmon Resonance Dip-Probe. Talanta, 68, 504.
http://dx.doi.org/10.1016/j.talanta.2004.09.029
[10] Wegfrass, A., Diethold, C., Werner, M., Resagk, C., Froblich, T., Halbedel, B. and Thess, A. (2012) Flow Rate Measurement of Weakly Conducting Fluids Using Lorentz Force Velocimetry. Measurement Science and Technology, 23, Article ID: 105307.
http://dx.doi.org/10.1088/0957-0233/23/10/105307
[11] Giovanetti, G., Frija, F., Menichetti, L., Hartwig, V., Viti, V. and Landini, L. (2010) An Efficient Method for Electrical Conductivity Measurement in the RF Range. Concepts in Magnetic Resonance Research B, 37B, 160.
http://dx.doi.org/10.1002/cmr.b.20165
[12] Kickhofel, J.L., Mohamide, A., Jalfin, J., Gibson, J., Thomas, P., Minerbo, G., Wang, H. and Homan, D.M. (2010) Inductive Conductivity Tensor Measurement for Flowline or Material Samples. Review of Scientific Instruments, 81, Article ID: 075102.
http://dx.doi.org/10.1063/1.3449320
[13] Hauge, B.L. and Helseth, L.E. (2012) Electromagnetic Resonance Circuit for Liquid Level Detection. European Journal of Physics, 333, 525.
http://dx.doi.org/10.1088/0143-0807/33/3/525
[14] Thess, A., Votyakov, E.V. and Kolesnikov, Y. (2006) Lorentz Force Velocimetry. Physical Review Letters, 96, Article ID: 164501.
http://dx.doi.org/10.1103/PhysRevLett.96.164501?
[15] Carmetal Dynamic Cad Software-Last Checked 2012-05-02
http://db-maths.nuxit.net/CaRMetal/index_en.html
[16] Helseth, L.E. (2012) Contactless Hybrid Sensor for Simultaneous Detection of Light Reflectance and Eddy Currents. Sensors and Actuators A, 173, 17.
http://dx.doi.org/10.1016/j.sna.2011.10.002
[17] Marquardt, D. (1963) An Algorithm for Least-Squares Estimation of Nonlinear Parameters. Journal of the Society for Industrial and Applied Mathematics, 11, 431.
http://dx.doi.org/10.1137/0111030
[18] Bethe, H.A. and Schwinger, J. (1943) Perturbation Theory of Resonant Cavities. NDRC Report Cornell University, D1-117.

  
comments powered by Disqus

Copyright © 2019 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.