Establishing the optimal conditions of the process of water treatment by ultrasound

Authors

  • Наталія Любомирівна Бернацька Lviv Polytechnic National University St. Bandera, 12, Lviv, Ukraine 79013, Ukraine

DOI:

https://doi.org/10.15587/1729-4061.2015.46495

Keywords:

acoustic cavitation, water treatment, reaction kinetics, biological contamination, chemical oxygen demand

Abstract

The efficiency of water treatment from chemical and biological contamination using ultrasound in the presence of oxygen was investigated in the paper. It was found that the necessary water quality parameters are obtained already after an hour of acoustic cavitation action in the presence of oxygen. Oxidation of water-soluble organic compounds during sonication is the first-order reaction. Dispersion of microorganisms is heterogeneous system and oxidation is the pseudo-second-order reaction. High COD decrease efficiency during sonication of oxygen in the atmosphere is caused by the fact that peroxy radicals, peroxides and oxoradicals, participating in the radical-chain oxidation of organic compounds are generated under cavitation and provide high process speed.

In aerobic conditions of storing dispersions, not treated with ultrasound, the COD value increases slowly, reaching a maximum for 6-10 days and remains constant. During storage of solutions with an excess of organic matter under aerobic conditions, the COD value decreased from 7181 mg/dm3 to 6504 mg/dm3 for 2 weeks. During storage of water, treated with ultrasound, the COD value remained constant for 2 weeks.

After ultrasonic treatment of contaminated water, post-effect of acoustic cavitation, which lies in reducing the number of microorganisms per unit volume and COD occurs. In the US-treated water, growth of microorganisms starts only after 24 hours. The results allow to choose optimal conditions for the water treatment process and use ultrasonic units to treat sewage of the food industry enterprises or use mobile ultrasonic units for household purposes, such as cleaning private pools.

Author Biography

Наталія Любомирівна Бернацька, Lviv Polytechnic National University St. Bandera, 12, Lviv, Ukraine 79013

Researcher

Department of general chemistry

References

  1. Goncharuk, V. V., Malyarenko, V. V., & Yaremenko, V. A. (2008). Use of ultrasound in water treatment. Journal of Water Chemistry and Technology, 30 (3), 137–150. doi: 10.3103/s1063455x08030028
  2. Chisti, Y. (2003). Sonobioreactors: using ultrasound for enhanced microbial productivity. Trends in Biotechnology, 21 (2), 4–6. doi: 10.1016/s0167-7799(02)00033-1
  3. Nasseri, S. (2006). Determination of the ultrasonic effectiveness in advanced wastewater treatment. Environmental Health Science Engeneering, 3 (2), 109–116.
  4. Kalumuck, K. M. (2003). Remediation and disinfection of water using jet generated cavitation. Fifth International Symposium on Cavitation, November 1-4, 5 –12.
  5. Mason, T., Cobley, A., Graves, J. (2011). New Evidence for the Inverse Dependence of Mechanical and Chemical Effects on the Frequency of Ultrasound. Ultrasonics Sonochemistry, 18 (1), 226–230. doi: 10.1016/j.ultsonch.2010.05.008
  6. Jambrak, A., Mason, T., Lelas, V., Paniwnyk, L., Herceg, Z. (2014). Effect of Ultrasound Treatment on Particle Size and Molecular Weight of Whey Protein. Journal of Food engineering, 121, 15–23. doi: 10.1016/j.jfoodeng.2013.08.012
  7. Chemat, F., Huma, Z., Khan, M. (2011). Appliction of Ultraound in Food Technology: Processing, Preservation and Extraction. Ultrasonics Sonochemistry, Vol. 18, Issue 4, 813–835. doi: 10.1016/j.ultsonch.2010.11.023
  8. Gao, S., Lewis, G. D., Ashokkumar, M., Hemar, Y. (2014). Inactivation of microorganisms by low-frequency high-power ultrasound:2. Asimple model for the inactivation mechanism. Ultrasonics Sonochemistry, 21 (1), 454–460. doi: 10.1016/j.ultsonch.2013.06.007
  9. Vasilyak, L. (2010). Ultrasound Application in Systems for the Disinfection of Water. Surface Engineering and Applied Electrochemistry, 46 (5), 489–493. doi: 10.3103/S1068375510050133
  10. Madhu, G., Rajanandam, K., Thomas, A. (2010). Cavitation Techniques for Wastewater Treatment: A Review. The IUP Journal of Chemical Engineering, 11 (3), 58–79.

Published

2015-08-19

How to Cite

Бернацька, Н. Л. (2015). Establishing the optimal conditions of the process of water treatment by ultrasound. Eastern-European Journal of Enterprise Technologies, 4(10(76), 8–12. https://doi.org/10.15587/1729-4061.2015.46495