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. 2021 Jan:70:105296.
doi: 10.1016/j.ultsonch.2020.105296. Epub 2020 Jul 31.

Degradation of benzene present in wastewater using hydrodynamic cavitation in combination with air

Pooja Thanekar  1 , Parag R Gogate  2 , Z Znak  3 , Yu Sukhatskiy  4 , R Mnykh  4
Affiliations

Degradation of benzene present in wastewater using hydrodynamic cavitation in combination with air

Pooja Thanekar et al. Ultrason Sonochem. 2021 Jan.

Abstract

The degradation of benzene present in wastewater using hydrodynamic cavitation (HC) alone as well as in combination with air has been studied using nozzles as cavitating device of HC reactor. Initially, the energy efficiency of the HC reactor operated at different inlet pressures was determined using the calorimetric studies. Maximum energy efficiency of 53.4% was obtained at an inlet pressure of 3.9 bar. The treatment processes were compared under adiabatic as well as isothermal conditions and it was observed that under the adiabatic condition, the extent of degradation is higher as compared to isothermal condition. Studies related to the understanding the effect of inlet pressure (range of 1.8-3.9 bar) revealed that the maximum degradation as 98.9% was obtained at 2.4 bar pressure using the individual operation of HC under adiabatic conditions and in 70 min of treatment. The combination of HC with air was investigated at different air flow rates with best results for maximum degradation of benzene achieved at air flow rate of 60 mL/sec. A novel approach of using cavitation for a limited fraction of total treatment time was also demonstrated to be beneficial in terms of the extent of degradation as well as energy requirements and cost of operation. Based on the cavitational intensity, the resonant radius of aggregates of cavitation bubbles was also determined for distilled water as well as for aqueous solution of benzene. Overall, significant benefits of using HC combined with air have been demonstrated for degradation of benzene along with fundamental understanding into cavitation effects.

Keywords: Air; Benzene degradation; Energy efficiency; Hydrodynamic cavitation; Nozzles; Process intensification.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1
Fig. 1
Details of experimental setup involving HC reactor. A: Schematic representation (1 - Feed tank; 2 – cooling system; 3 - stirrer; 4 - air inlet; 5, 7, 14, 16 -valves; 6 - circulation pump; 8 – cavitating device; 9 - thermometer; 10 - hydrophone; 11 - PC; 12 - rheometer; 13 - compressor; 15 – manometer) B: Actual Photograph.
Fig. 2
Fig. 2
Temperature rise profile at different inlet pressures for estimation of energy efficiency.
Fig. 3
Fig. 3
Effect of inlet pressure on the extent of degradation of benzene under adiabatic conditions.
Fig. 4
Fig. 4
Kinetic data fitting for the degradation of benzene at different inlet pressures under adiabatic conditions.
Fig. 5
Fig. 5
Effect of combination of HC with air on the extent of degradation of benzene under adiabatic conditions.
Fig. 6
Fig. 6
Kinetic data fitting for the combination of HC with air on the extent of degradation of benzene under adiabatic conditions.
Fig. 7
Fig. 7
Effect of inlet pressure on the extent of degradation of benzene under isothermal conditions.
Fig. 8
Fig. 8
Kinetic data fitting for combination of HC with air on the extent of degradation of benzene under isothermal conditions.
Fig. 9
Fig. 9
Results for novel approach of using cavitation limited for initial 30 min of treatment time.
Fig. 10
Fig. 10
Intensity of the acoustic signal of the cavitation field generated in A. Water B. aqueous solution of benzene.
See this image and copyright information in PMC

References

    1. Meckenstock R.U., Boll M., Mouttaki H., Koelschbach J.S., Cunha Tarouco P., Weyrauch P., Dong X., Himmelberg A.M. Anaerobic degradation of benzene and polycyclic aromatic hydrocarbons. J. Mol. Microbiol. Biotechnol. 2016;26:92–118. - PubMed
    1. Ramteke L., Gogate P.R. Removal of ethylbenzene and p-nitrophenol using combined approach of advanced oxidation with biological oxidation based on the use of novel modified prepared activated sludge. Process Saf. Environ. Prot. 2015;95:146–158.
    1. Ohio Department of Health, BTEX (Benzene, Toluene, Ethylbenzene, and Xylenes), 2009 (Available on) http://www.odh.ohio.gov/~/media/ODH/ASSETS/Files/eh/HAS/btex.ashx.
    1. Han X., Peng S., Zhang L., Lu P., Zhang D. The Co-occurrence of DNRA and Anammox during the anaerobic degradation of benzene under denitrification. Chemosphere. 2020;247 - PubMed
    1. Xiang Y., Zhu Y., Lu J., Zhu C., Zhu M., Xie Q., Chen T. Co3O4/α-Fe2O3 catalyzed oxidative degradation of gaseous benzene: Preparation, characterization and its catalytic properties. Solid State Sci. 2019;93:79–86. doi: 10.1016/j.solidstatesciences.2019.05.008. - DOI

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