Optimization of Ozone Action Conditions in O3/BAC Process
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
11
Page:
33-38
Column:
Date of publication:
2020-06-05
- Keywords:
- font-size: 10pt; ">ozone; biological activated carbon; ozone CT value; ozone dosing ratio; formaldehyde; organic matter
- Abstract:
-
In order to optimize the operational efficiency of ozone/upflow biological activated carbon (O 3/BAC) process treating Changdang Lake raw water, formation rule of formaldehyde in a bench-scale equipment during ozonation process was explored by using response surface methodology designed by Box-Behnken Design. The effects of ozone CT value (C: ozone concentration; T: ozone contact time) and ozone dosing ratio on purification efficiency of O3/BAC in a pilot plant were explored, and the operational parameters of ozonation were optimized. In the ozonation process, the influence degree of each water quality factor on formaldehyde formationin descending order was TOC concentration, ozone dosage, pH and Br-1 concentration, respectively. With the increase of ozone dosage, the formaldehyde in the effluent increased first and then decreased. For the raw water from Changdang Lake, CODMn, UV254, ammonia nitrogen, trihalomethane formation potential and formaldehyde were taken as the control indexes, and the ozone CT value and ozone dosing ratio were suggested to be 0.45 mg·min/L (the corresponding ozone dosage was 1 mg/L, and the ozone contact time was 15 min) and 3 ∶1 ∶1. At the same time, ozone could significantly change the properties of organic matter under the above operational condition according to the results of liquid chromatography and organic carbon analyzer, which was helpful to improve the treatment efficiency of biological activated carbon.
Last Update:
2020-06-01