Optimization of the O_(3)/H_(2)O_(2) process with response surface methodology for pretreatment of mother liquor of gas field wastewater  

作　　者：Haoran Feng Min Liu Wei Zeng Ying Chen 

机构地区：[1]College of Architecture and Environment,Sichuan University,Chengdu,610065,China

出　　处：《Frontiers of Environmental Science & Engineering》2021年第4期337-349,共13页环境科学与工程前沿（英文）

基　　金：This study was supported by the National Science and Technology Major Project of the 13th Five-Year Plan“High-efficiency development of ultra-deep bio-herm gas reservoirs with bottom water”(No.2016ZX05017-005).

摘　　要：The present study reports the use of the O_(3)/H_(2)O_(2) process in the pretreatment of the mother liquor of gas field wastewater(ML-GFW),obtained from the multi-effect distillation treatment of the gas field wastewater.The range of optimal operation conditions was obtained by single-factor experiments.Response surface methodology(RSM)based on the central composite design(CCD)was used for the optimization procedure.A regression model with Total organic carbon(TOC)removal efficiency as the response value was established(R^(2)=0.9865).The three key factors were arranged according to their significance as:pH>H_(2)O_(2) dosage>ozone flow rate.The model predicted that the best operation conditions could be obtained at a pH of 10.9,an ozone flow rate of 0.8 L/min,and H_(2)O_(2) dosage of 6.2 mL.The dosing ratio of ozone was calculated to be 9.84 mg O3/mg TOC.The maximum removal efficiency predicted was 75.9%,while the measured value was 72.3%.The relative deviation was found to be in an acceptable range.The ozone utilization and free radical quenching experiments showed that the addition of H_(2)O_(2) promoted the decomposition of ozone to produce hydroxyl radicals(·OH).This also improved the ozone utilization efficiency.Gas chromatography-mass spectrometry(GC-MS)analysis showed that most of the organic matters in ML-GFW were degraded,while some residuals needed further treatment.This study provided the data and the necessary technical supports for further research on the treatment of ML-GFW.

关 键 词：High salinity High organic matters Gas field wastewater O_(3)/H_(2)O_(2) Response surface methodology 

分 类 号：X703[环境科学与工程—环境工程]