Using high frequency and low-intensity ultrasound to enhance activated sludge characteristics

Parviz Mohammadi; Nasim Karami; Ali Akbar Zinatizadeh; Farzaneh Falahi; Nasrin Aghamohammadi; Ali Almasi

doi:10.1016/j.ultsonch.2019.01.030

Using high frequency and low-intensity ultrasound to enhance activated sludge characteristics

Ultrason Sonochem. 2019 Jun:54:274-280. doi: 10.1016/j.ultsonch.2019.01.030. Epub 2019 Jan 22.

Authors

Parviz Mohammadi¹, Nasim Karami¹, Ali Akbar Zinatizadeh², Farzaneh Falahi³, Nasrin Aghamohammadi⁴, Ali Almasi¹

Affiliations

¹ Research Center for Environmental Determinants of Health, Department of Environmental Health Engineering, School of Public Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.
² Environmental Research Center (ERC), Department of Applied Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.
³ Research Center for Environmental Determinants of Health, Department of Environmental Health Engineering, School of Public Health, Kermanshah University of Medical Sciences, Kermanshah, Iran. Electronic address: falahi.farzaneh@gmail.com.
⁴ Centre for Occupational and Environmental Health, Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia. Electronic address: nasrin@ummc.edu.my.

PMID: 30712854
DOI: 10.1016/j.ultsonch.2019.01.030

Abstract

In this study, high-frequency ultrasound wave (1.8 MHz) at low intensity was applied to improve activated sludge settleability at high MLSS concentration. The effect of irradiation intensity, sonication mode, MLSS concentration and sample volume on the physical characteristics of sludge in a pilot scale settling column were investigated for optimizing the conditions. The obtained results showed that high-frequency ultrasound decreased the height of sludge (44%) and effluent turbidity (82.2%) and increased sludge settling velocity about 3 times at high biomass concentration. Irradiation intensity of 0.4 w/cm² and sonication mode with interval times of 10 s showed the best results on the performance of the system at MLSS concentration of 8000 mg/L with a sample volume of 3 L.

Keywords: High frequency; Irradiation intensity; Sludge settleability; Ultrasound wave.

MeSH terms

Biomass
Sewage*
Sonication*
Waste Disposal, Fluid / methods*

Substances

Sewage