Adsorption of MIB/geosmin by powdered activated carbon (PAC) in conventional water treatment：From bench-scale HSDM prediction to full-scale samplings

Abstract

Adsorption of two taste and odour (T&O) compounds 2-methylisoborneol (MIB) and geosmin in the presence of natural organic matter (NOM) by powdered activated carbon (PAC) were investigated in bench pilot-scale experiments and field samplings at full-scale water treatment plants (WTP) Homogeneous surface diffusion model (HSDM) was used to simulate the adsorption data from the past ensuing prediction results were developed and utilised for verifying current experimental data Concentration of MIB and geosmin were measured using solid-phase microextraction (SPME) with gas chromatography mass-spectrometer (GC-MS) and percent removal of T&O compounds are independent of initial concentration could be found in the results of bench and pilot trials In low natural turbidity water addition of alum and subsequent formation of coagulant flocs appeared to have no obviously adverse impact on kinetics adsorption of MIB/geosmin This implied the coagulant flocs may not be the major factor contributed the discrepancy between prediction result which established from the jar tests with applying PAC only and experimental data In our experiments HSDM prediction overestimated the current adsorption efficiency of PAC with prediction displayed lower percent remaining than the result of experiments and full-scale samplings Although good corresponding performance of MIB/geosmin removal can be observed between bench and pilot-scale the results from WTP were not the case Unpredictable MIB/geosmin concentration was revealed throughout the full-scale water treatment chains which weakly corresponded to both scale experimental results as well as HSDM prediction and indicates the unknown mixing and hydraulic profile within plant-scale processes Findings in our study necessitate more robust managing or modelling approaches for immediate response to taste and odour issues

Date of Award	2017 Aug 2
Original language	English
Supervisor	Tsair-Fuh Lin (Supervisor)