Chemical Engineering Transactions (Nov 2021)
Aeration Supported Process Intensification of Waste Water for Degradation of Benzene in an Orifice Type Hydrodynamic Cavitation System
Abstract
Isolated and aerated benzene degradation in the wastewater using orifice plates as the caviting devices for the hydrodynamic cavitation (HC) reactor was investigated. Initially, calorimetric tests were used to measure the energy efficiency of the HC reactor run at various inlet pressures. At an inlet pressure of 3.0 bar, the maximum energy efficiency of 55.8 % was achieved. In both isothermal and adiabatic treatment conditions, the treatment procedures were compared, and the degree of deterioration in comparison with the isothermal condition was observed in the adiabatic condition. The study related to understanding the impact of inlet pressure has revealed that the maximum degradation of 99.7 % was obtained at 3 bar pressure using the HC's individual activity under adiabatic conditions in 90 min of treatment. The combination of HC and air at different airflow rates were investigated with the best results for maximum benzene depletion at an airflow rate of 65 mL/s. A novel approach to cavitation was also illustrated in terms of the level of degradation, energy demand and operating costs for a small fraction of the overall processing time. The resonant radius from cavitation bubbles aggregates was also calculated based on the strength of the cavitation in both distilled water and aqueous benzene. Overall, important advantages for degradation of benzene along with an understanding of cavitation effects have been shown by HC in combination with air.