초록
<P><B>Abstract</B></P> <P>A long-term evaluation of hythane generation from unsaturated polyester resin wastewater contaminated by 1,4-dioxane and heavy metals was investigated in a continuous up-flow anaerobic self- separation gases (UASG) reactor inoculated with mixed culture. The reactor was operated at constant hydraulic retention time (HRT) of 96h and different organic loading rates (OLRs) of 0.31±0.04, 0.71±0.08 and 1.07±0.06gCOD/L/d. Available data showed that volumetric hythane production rate was substantially increased from 0.093±0.021 to 0.245±0.016L/L/d at increasing OLR from 0.31±0.04 to 0.71±0.08gCOD/L/d. However, at OLR exceeding 1.07±0.06gCOD/L/d, it was dropped to 0.114±0.016L/L/d. The reactor achieved 1,4-dioxane removal efficiencies of 51.8±2.8, 35.9±1.6 and 26.3±1.6% at initial 1,4-dioxane concentrations of 1.14±0.28, 1.97±0.41 and 4.21±0.30mg/L, respectively. Moreover, the effect and potential removal of the contaminated by heavy metals (i.e., Cu<SUP>2+</SUP>, Mn<SUP>2+</SUP>, Cr<SUP>3+</SUP>, Fe<SUP>3+</SUP> and Ni<SUP>2+</SUP>) were highlighted. Kinetic modelling and microbial community dynamics were studied, according to each OLR, to carefully describe the UASG performance. The economic analysis showed a stable operation for the anaerobic digestion of unsaturated polyester resin wastewater using UASG, and the maximum net profit was achieved at OLR of 0.71±0.08gCOD/L/d.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bio-hythane production from polyester wastewater via UASG reactor was assessed. </LI> <LI> Impacts of influent contamination by 1,4-dioxane and heavy metals were discussed. </LI> <LI> Maximum volumetric H<SUB>2</SUB> and CH<SUB>4</SUB> productions of 0.12 and 1.06L/L/d were achieved. </LI> <LI> Significant drop in CH<SUB>4</SUB> production was resulted at OLR up to 1.07±0.06gCOD/L/d. </LI> <LI> Bioenergy recovery through UASG economically achieved a net profit of 10,231$/y. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>