Method and apparatus for monitoring and controlling ozonation and aerated filtration using UV and visible spectral measurement and oxidation reduction potential

摘要

The present invention relates to a method and system for monitoring and controlling the process train of ozonation and biologically aerated filtration used in water and wastewater treatment. The process monitoring and control can be achieved by online measurement of UV/Vis absorption at one or multiple wavelengths and oxidation/reduction potential values which are compared to predetermined UV absorption and oxidation/reduction values. The air and ozone dosage of the effluent are then adjusted based on the measured values of UV/Vis absorption and oxidation/reduction potential of the effluent.

主权项

1. A method for monitoring and controlling a process train of air and ozone dosage used in water and wastewater treatment comprising the following steps:
(a) obtaining an online measurement of the UV/Vis absorption of an effluent; (b) comparing the online measurement of the UV/Vis absorption measured for the effluent with a predetermined UV/Vis absorption value stored in a microprocessor; (c) obtaining an online measurement of the oxidation/reduction potential of the effluent; (d) comparing the online measurement of the oxidation/reduction potential measured for the effluent with a predetermined oxidation/reduction potential value stored in the microprocessor; and (e) adjusting the air and ozone dosage of the effluent based on the online measurements of the UV/Vis absorption and oxidation/reduction potential of the effluent as follows:
i. reduce the air flow rate when the online measurement of the UV/Vis absorption is lower than the predetermined UV/Vis absorption and the online measurement of the oxidation/reduction potential is higher than the predetermined oxidation/reduction potential;ii. reduce the ozone dosage when the online measurement of the UV/Vis absorption is lower than the predetermined UV/Vis value and the online measurement of the oxidation/reduction potential is lower than or equal to the predetermined oxidation/reduction potential;iii. increase the ozone dosage when the online measurement of the UV/Vis absorption is higher than the predetermined UV/Vis value and the online measurement of the oxidation/reduction potential is higher than or equal to the predetermined oxidation/reduction potential;iv. increase the air flow rate when the online measurement of the UV absorption is higher than the predetermined UV/Vis value and the online measurement of the oxidation/reduction potential is lower than the predetermined oxidation/reduction potential; orv. keep the air flow rate and ozone dosage unchanged when the online measurement of the UV absorption is equal to the predetermined UV/Vis value.