Liu M H, Li Y H, Yang M, et al.Effects of temperature， turbidity and pH on fluorescence characteristics of offshore oil in water and their compensation[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(6):100-107.

doi:10.16186/j.cnki.1673-9787.2024030074

Received:2024/06/01

Revised:2024/08/25

Published:2026/10/09

Effects of temperature， turbidity and pH on fluorescence characteristics of offshore oil in water and their compensation

Liu Minghui1, Li Yahui2, Yang Min3, Wang Xinle1, Lin Chen1, Wang Hanyu3, Feng Yongkang1, Pan Zihe4

1.CNOOC Energy Technology & Services Limited， Safety and Environmental Protection Branch， Research Institute of Safety and Environmental Engineering， Tianjin  300457， China；2.Laoshan Laboratory， Qingdao  266200， Shandong， China；3.North China Sea Marine Technical Center， Ministry of Natural Resource， Qingdao  266033， Shandong， China；4.Institute of Resources and Environmental Engineering， Shanxi University， Taiyuan  030031， Shanxi， China

Abstract: Objectives To address the multiple interferences—large temperature fluctuations， turbidity changes caused by suspended solids， and pH variations due to chemical dosing—in the detection of oil content in produced water from offshore oil platforms using UV fluorescence， a targeted anti-interference detection system was developed.  Methods Oil-in-water samples were prepared using Bohai crude oil as the solute. Fluorescence spectrophotometry and a self-developed near-UV oil-in-water sensor were employed. Based on the fluorescence spectral characteristics of the samples， the fluorescence peaks and adjacent spectral data were analyzed to investigate the effects of temperature， turbidity， and pH on the fluorescence spectra. Compensation models were established to correct the interferences caused by variations in these parameters.  Results The results show that changes in temperature， turbidity， and pH of produced water affect fluorescence intensity， but the fluorescence peak positions remain unchanged. Fluorescence intensity is negatively correlated with temperature （fitting coefficient： 0.983 5）， negatively correlated with turbidity （fitting coefficient： 0.980 4）， and positively correlated with pH （fitting coefficient： 0.975 2）.Compensation models for temperature， turbidity， and pH were developed， and the relative errors between the compensated fluorescence intensities and their respective reference values were calculated. With the fluorescence intensity at 25 °C as the reference， the overall relative error of the temperature compensation model was less than 5% and remained below 2% at temperatures up to 35 °C. With the fluorescence intensity at 0 NTU as the reference， the overall relative error of the turbidity compensation model was less than 2%. With the empirical pH value of 6.7 for actual platform water samples as the reference， the overall relative error of the pH compensation model was less than 3%.  Conclusions The proposed compensation models can effectively correct the influence of environmental variations on UV fluorescence detection of oil concentration in water， significantly improving detection accuracy.

Key words: oil-in-water; UV fluorescence; environmental factor; impact analysis; compensation