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Wen Z.-C.,Renmin University of China | Wen Z.-C.,CAS Institute of Process Engineering | Ma S.-H.,CAS Institute of Process Engineering | Zheng S.-L.,CAS Institute of Process Engineering | And 2 more authors.
Environmental Science and Pollution Research | Year: 2016

Red mud storage facility (RM-SF) pollution remains a serious problem in China mainly due to the RM’s huge quantity, little recyclability, and high alkalinity. And, there is also a risk of dam failure because almost all RM-SFs are processed by damming. In order to address this challenge and improve the level of risk management, it is necessary to evaluate the environmental risk of RM-SFs systematically. So, this paper firstly designs a comprehensive evaluation index system with a three-level evaluation index in the terms of RM characteristics, RM-SF characteristics, ambient environment of RM-SF, the management of RM-SF, and the application aspect of RM by the analytic hierarchy process (AHP) method. Then, a case of RM-SF from a typical alumina production enterprise is studied according to this system, as is assisted by several experts from different fields when determining the weights of all indicators. The results show that the risk of selected RM-SF primarily depends on the former factors, that is, RM and RM-SF characteristics, while the contributions of the other factors are quite smaller. © 2016 Springer-Verlag Berlin Heidelberg Source

Du P.,Peking University | Li K.,Peking University | Li J.,Peking University | Xu Z.,Peking University | And 4 more authors.
Water Research | Year: 2015

Sewage-based epidemiology was applied to examine geographic variations in methamphetamine (METH) and ketamine (KET) use in China. Influent and effluent wastewater samples were collected from 36 sewage treatment plants (STPs) in 18 major cities that cover all the geographic regions of the country. Mean METH loads of the cities ranged from 12.5±14.9 to 181.2±6.5mg/1000inh/d, whereas mean KET loads ranged from <0.2 to 89.6±27.4mg/1000inh/d. No clear geographical pattern was observed in METH use, although slightly lower use in north and east China relative to other regions can be suggested. In contrast, an overall increasing trend from the north to the south was evident for KET loads. Apparent METH removal was greater than 80% at most STPs, whereas KET removal was less than 50% at most STPs and was even negative (i.e., measured effluent concentrations were greater than influent concentrations) at a significant number of STPs. Results in Beijing, Shanghai, and Shenzhen indicate that METH use in China may have increased substantially since 2012, whereas KET use did not significantly change, if not decreased. Comparison between seizures and estimated consumptions reveals that seizures in most Chinese provinces are far less than consumptions. In several provinces (e.g., Guangdong and Yunan), however, seizures were found to exceed consumptions, indicating that a significant fraction of METH and KET seized in these provinces is destined for consumption in other places. © 2015 Elsevier Ltd. Source

Li J.,Peking University | Li J.,McGill University | Hou L.,Peking University | Du P.,Peking University | And 6 more authors.
Science of the Total Environment | Year: 2014

Sewage epidemiology has been proven as an effective approach to estimate the use of illicit drugs by a population. In this study, sewage analysis was applied to examine the patterns of amphetamine (AMP) and methamphetamine (METH) uses in the urban area of Beijing. Influent and effluent samples were collected from all the thirteen sewage treatment plants (STPs) in the urban area during two sampling campaigns. METH concentrations in influents were found to range from several tens to several hundred ng·L-1, whereas AMP concentrations ranged from several to several tens ng·L-1. The concentration ratios between AMP and METH in influents at most STPs were close to the rate of AMP excretion following METH ingestion, indicating that AMP in sewage in Beijing was predominately from the metabolism of METH. Much higher METH loads were observed in the center part of the urban area in Beijing, indicating a strong correlation between METH use and economic level and entertainment activities. Seasonal variation in METH loads was significant, with greater use in summer than in winter. Significant difference in METH loads between weekdays and weekend days were observed in winter but not in summer. No clear trend in diurnal variation of METH use was observed. Nearly complete removal of METH occurred at the STPS in Beijing. Apparent removal rates of AMP were lower than those of METH, likely due to degradation of METH into AMP during the wastewater treatment processes. In summary, this study represents the first application of sewage epidemiology to the entire urban population of a metropolitan in mainland China and provided an overview of METH and AMP uses in the city. © 2014 Elsevier B.V. Source

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