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In this research, three highly efficient combination systems, including constructed wetland microbial fuel cell (CWMFC), hydrolytic sludge acidification coupling with constructed wetland microbial fuel cell (HSA-CWMFC) and hydrolytic filler acidification coupling with constructed wetland microbial fuel cell (HFA-CWMFC), were applied to the removal of pollutants from domestic sewage. The three combination systems could effectively treat domestic sewage and generate clean energy. The power generated by CWMFC, HSA-CWMFC, and HFA-CWMFC was 0.36 W/m2, 0.40 W/m2, and 0.43 W/m2, respectively. The results indicated that the removal rates of chemical oxygen demand (COD), total organic carbon (TOC), total phosphorus (TP), ammonia nitrogen (NH 3 –N), and nitrate nitrogen (NO 3 −-N) in HFA-CWMFC could achieve the optimal values of 91.01%, 90.63%, 95.35%, 86.11%, and 91.01%, respectively. In addition, HFA-CWMFC produced more organic acids than HSA-CWMFC, which was beneficial to the follow-up reaction. Through qualcomm sequencing analysis, it could be seen that Firmicutes , which could enhance power generation capacity and increase removal rates of pollutants, played an important role in HFA-CWMFC. The results demonstrated that the three combined systems had excellent application prospects for sewage treatment and energy generation. [Display omitted] ● The hydrolytic combination systems had remarkable effect on pollutants removal. ● The hydrolytic filler combination system could obviously remove pollutants. ● Microbial community in the hydrolytic filler combination system was more abundant. [ABSTRACT FROM AUTHOR]

Quarry stone powder is one of the solid waste, which can create obvious environmental risks. To solve this problems, 22.2%–44.4% of cement is replaced by two types of quarry stone powder (basalt and limestone powders) in producing an environmentally-friendly ultra-high performance concrete (UHPC) in this study. The material mix design is followed on the basis of the modified Andreasen and Andersen (MAA) model. Then, the impact of the quarry stone powders on fresh and hardened properties of UHPC are investigated, including flowability, compressive strength, early hydration kinetics, and durability. The results indicate that the incorporation of quarry stone powder can significantly improve the flowability, slow down the early hydration rate of cement and decrease autogenous shrinkage of UHPC during early age. Besides, the addition of quarry stone powder could decrease the strength of UHPC at 7 days, while its strength is comparable with the reference mix at 56 days. The carbon dioxide (CO 2) emissions calculation shows that application of quarry limestone powder can significantly reduce the environmental burden of UHPC, which means the produced UHPC can be treated as a green building material with advanced properties in the near future. • Quarry stone powders can be used to produce eco-friendly UHPC. • The flowability of UHPC was improved by including stone powder. • Autogenous shrinkage of UHPC can be reduced by adding quarry stone powder. • The produced UHPC with quarry stone powders has good durability. • The microstructure of the produced UHPC with quarry stone powders is dense. [ABSTRACT FROM AUTHOR]