Zahra Raeyati - Department of Chemical Engineering, Faculty of Engineering, Islamic Azad University,Shahrood Quality control department of Semnan Water &Waste Water Company,Semnan, Iran
Mahmood Torabi Angaji - School of Chemical Engineering, Tehran University Tehran, Iran

Cavitation phenomenon is resulted from elevated temperature and pressure and production of free radicals. This technology can be employed to disinfect drinking water and waste water. What is important in cavitation reactors is the production of hydroxyl radicals, which plays a significant role in removing coliforms. So, it was attempted to control radical production through controlling the input pressure. It was examined by placing a PID controller. The presented control algorithm is carried out based on trial and error. Flow diagram of hydroxyl radical control model was also designed using pressure. The relationship between design in term of cavitational intensity (according to collapsing pressure and temperature) and cavitational efficiency (according to radical ) will be based on operational parameters regarding the hydrodynamic cavitation in order to perceive the design information concerning cavitational intensity and radical efficiency.

component; hydrodynamic cavitation, radical , collapsing pressure and temperature, cell decomposition, PID controller