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Normalization is applied to calculate the magnitude of an impact relative to the total impact of a given reference in Life Cycle Assessment (LCA). Normalized profiles of environmental impacts depend on geographical areas due to differences in the industrial and economic activities. So far, Normalization factors for China are not developed to conduct life cycle assessment analysis. The purpose of this research is to propose a database of normalization factors (NFs) covering 18 environmental impact categories in a Chinese context to fill the research gap. To establish the local database, we collected the domestic inventory of emission and resources extraction in China with necessary data extrapolation and then calculated the normalization factors based on the international model ReCiPe2016. Furthermore, normalization factors for each impact category are differentiated into individual and national levels, and the substance contribution proportion of the 18 environmental impact categories is quantified. In addition, we used the Data Quality Indicator (DQI) model to evaluate the data source of impact categories, while analyzing the uncertainty of normalization factors quantitatively based on the evaluation result. The results of the quantitative analyses showed uncertainty intervals for the normalization factors. It was found that ionizing radiation and toxicity got the largest uncertainty intervals among the normalization factors for all impact categories, owing to the low completeness of the inventory of substances in those two impact categories. According to the data quality indicators of impact categories, we located the data gap in domestic inventory and proposed measures to promote comprehensiveness of inventory. This China Normalization Factors Database provides the LCA researchers with a starting point for a subsequent weighing step and improves the accuracy of LCA study at the Chinese territory. • The domestic inventory of emission and resources extraction in China is collected. • A normalization factor database of LCA in China is established. • The characteristic pollutants identified in China are compared with those in the world. • A data quality matrix analysis of impact category is built for the uncertainty analysis. • Measures to diminish uncertainty are raised. [ABSTRACT FROM AUTHOR]

The insufficient removal of pollutants and bioelectricity production have become a bottleneck for high-concentration saline wastewater treatment through microbial fuel cell (MFC) technology. Herein, a novel supercapacitor MFC (SC-MFC) was constructed with carbon nanofibers composite electrodes to investigate pollutant removal ability, power generation, and electrochemical properties using real landfill leachate. The possible extracellular electron transfer and nitrogen element conversion pathways in the bioanode were also analyzed. Results showed that the SC-MFC had higher pollutant removal rates (COD: 59.4 ± 1.2%; NH 4 +-N: 78.2 ± 1.6%; and TN: 77.8 ± 1.2%), smaller internal impedance R t (∼6 Ω), higher exchange current density i 0 (2.1 × 10−4 A cm−2), and a larger catalytic current j 0 (704 μA cm−2) with 60% leachate than those with 10% and 20% leachate, resulting in a power output of 298 ± 22 mW m−2. Ammonium could be incorporated by chemoautotrophic bacteria to produce organic compounds that could be further utilized by heterotrophs to generate power when biodegradable organic matters are depleted. Three conversion pathways of nitrogen might be involved, including NH 4 + diffusion from anode to cathode chamber, nitrification, and the denitrification process. Additionally, cyclic voltammetry tests showed that both the direct electron transfer (DET) and the mediator electron transfer in bioanode were involved and dominated by DET. The microbial analysis revealed that the bioanode was dominated by salt-tolerant denitrifying bacteria (38.5%), which was deduced to be the key functional microorganism. The electrochemically active bacteria decreased significantly from 61.7% to 4% over three stages of leachate treatment. Overall, the SC-MFC has demonstrated the potential for wastewater treatment along with energy harvesting and provides a new avenue toward sustainable leachate management. Image 1 • A novel supercapacitor MFC was designed to treat landfill leachate. • Superior catalytic activity of as-prepared electrode led to high power output. • Three conversion pathways of nitrogen were involved in bioanode. • Electron transfer in bioanode was dominated by direct electron transfer. • High salt-tolerant denitrifying bacteria extensively existed in bioanode. [ABSTRACT FROM AUTHOR]