Transfer And Transform Of Galaxolide And Tonalide By A~2O Process

Polycyclic musks (PCMs) is on the behalf of the pharmaceutical and personal care products(PPCPs), are used frequently as fragrances in washing powders, shampoos and other consumer products, which are supposed to smell nicely. They are hydrophobic and lipophilic, and show weak estrogenic activity. As the important ingredients of PPCPs, more attention now had been paid to PCMs on their impact on ecological system and human health. Up to date, the study on PCMs distribution characters and transfer mechanism in environment is one of the difficulties and hotspots in respects of environmental science research.In this paper, Galaxolide (HHCB) and Tonalide (AHTN) were chosen as the representative ingredients of PCMs for studying on the changes of concentrations of HHCB and AHTN in aqueous phase and sewage sludge under different HRT and SRT conditions and the effects of HRT and SRT on fate of the targets by A2O process. Solid phase extraction (SPE) and gas chromatography mass spectrometry (GC/MS) were applied to determine concentrations of the targets in aqueous phase and sewage sludge. Meantime, correlation analysis was applied to study concentrations of the targets in aqueous phase and sewage sludge under different HRT and SRT conditions and oxygen environment conditions. And it compared to the changes of remove rates, removal contribution rate and the total removal rates of different reaction tanks. In the procedure, the model of the transfer and transformation of the targets by A2O process was established based on Matlab GUI. It can provide scientific basis for the study on the targets pollution controlling and the foundation of relevant environmental assessment.In the first, the results of HHCB and AHTN in the different conditions of HRT (6h,8h,10h and12h) during A2O process show that, HRT has an influence up on the proportions of biodegradation and the discharge of excess sludge for HHCB by A2O process, but it affects the discharge of excess sludge for AHTN. With the extension of HRT, removal rates and removal contribution rates of HHCB and AHTN decrease in the anaerobic tank, while increasing in the anaerobic tank and aerobic tank. The final removal rates of the targets in the four operating conditions are73.93%,73.05%,75.14%,76%and48.76%and44.27%,57.17%,62.9%, respectively. Removal efficiency is good for HHCB, but the removal efficiency of AHTN is poor by A2O process. Meanwhile, with the extension of HRT, the removal efficiency has no significant effect on HHCB, and it promoted the removal efficiency of AHTN.Secondly, the results of the targers in the different conditions of SRT (5d,10d,15d and20d) during A2O process show that, biodegradation is the main pathway of the targets by A2O process. SRT has an influence up on the discharge of excess sludge for HHCB and AHTN. With the extension of SRT, accounted for the proportion of the discharge of excess sludge significantly reduce. The final removal rates of the gargets in the four operating conditions were74.41%,75.14%,67.38%,67.76%, and42.38%,57.17%,32.20%,33.66%, respectively. Removal efficiency is good for HHCB, but the removal of AHTN is poor by A2O process. Meanwhile, it promotes the total removal efficiency of HHCB and AHTN with the extension of SRT.Finally, the transfer and transformation model of the targets was set up based on the module of biological degradation, volatilization, the discharge of excess sludge and the discharge of effluent by A2O process. Moreover, computer modeling and simulation function was developed using the Matlab GUI based on the model. The results show that, the relative error of effluent concentrations of the targets is<19%and<16%under different HRT and SRT conditions, respectively, and the relative errors are <5%under many conditions. It is considered that the model can facilitate prediction of effluent concentrations under different conditions by A2O process. At the same time, the dialy total amounts of four ways of the transfer and transformation is<7μg·d-1and <5μg·d-1, respectively, and the percentages is <26%and <28%, respectively, the predictions of effluent concentrations and fate of AHTN are much more accurate than HHCB.