Using sonochemical reactor for degradation of LAS from effluent of wastewater treatment plant
ABSTRACT Linear alkylbenzene sulfonates (LAS) are anionic surfactants, which are found in relatively high amounts in domestic and industrial wastewaters. The effectiveness of using sonochemical reactor for the degradation of LAS from effluent of wastewater treatment plant has been investigated. In this study, experiments of LAS solution were performed using methylene blue active substances (MBAS) method. The effectiveness of sonochemical reactor for LAS degradation is evaluated with emphasis on the effect of sonication time and initial LAS concentration. Experiments were carried out at initial concentrations of 0.2 mg/L, 0.5 mg/L, 0.8 mg/L and 1 mg/L, frequency of 130 kHz, acoustic power value of 400 W, temperature of 18–20 °C and pH value of 6.8–7. This study showed that LAS degradation was found to increase with increasing sonication time. In addition, as the concentration is increased, the LAS degradation rate decreases in the sonochemical reactor.
- The Journal of Physical Chemistry. 04/2002; 95(9).
- Journal of Environmental Engineering-asce - J ENVIRON ENG-ASCE. 01/2006; 132(2).
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ABSTRACT: This study was done to investigate the reduction of anaerobic bacteria (Clostridium perfringens) by ultrasound irradiation technology (USI). C. perfringens is the most important of the sulfite-reducing clostridia and is normally present in human and animal feces. Clostridial spores survive longer than coliforms, Escherichia coli or enterococci, and are consequently used as an indicator of past fecal pollution. The spores are not always inactivated by chlorination, but are not a hazard to health in potable water. C. perfringens are very resistant to chlorine and other drinking-water disinfectants. Conventional water treatment practices including chlorination are sometimes inadequate for inactivation of C. perfringens. Ultrasound irradiation is able to inactive C. perfringens through a number of physical and chemical effects arising from acoustic cavitation. The phenomenon of cavitation, which involves formation, growth, and violent collapse of vapour bubbles in a liquid media, is known to generate a high-intensity pressure, which affects the cell and C. perfringens' viability. Cavitations disrupt C. perfringens. Ultrasound irradiation at a frequency of 42 kHz was used to expose aqueous suspension of C. perfringens to evaluate the disinfection efficacy of ultrasound irradiation. Results indicated a significant increase in reduction of C. perfringens with increasing ultrasound time. C. perfringens was inactivated by 99.98% after 90 min.Environmental Technology 12/2008; 29(11):1145-8. · 1.61 Impact Factor