Perfluorinated compounds(PFCs)have been widely used for more than 50 years due to their excellent thermal stability and hydrophobic/hydrophilic *** some PFCs have been known to be persistent,bioaccumulative and tumori...
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Perfluorinated compounds(PFCs)have been widely used for more than 50 years due to their excellent thermal stability and hydrophobic/hydrophilic *** some PFCs have been known to be persistent,bioaccumulative and tumorigenic,the presence of PFCs in environment has been recognized as one of the emerging
In this paper, stormwater runoff from an urban traffic road and building located in Beijing, China, was characterized to measure the stormwater runoff discharge rates and pollutant concentrations. Based on monitoring,...
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Energy-related carbon emissions in China have increased significantly. To mitigate these emissions, it is necessary to estimate the trends (increase or decrease) and the magnitudes of the influences (tons of carbon em...
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Energy-related carbon emissions in China have increased significantly. To mitigate these emissions, it is necessary to estimate the trends (increase or decrease) and the magnitudes of the influences (tons of carbon emitted) as a result of four causal factors that affect emissions: GDP, economic structure, energy intensity, and fuel mix. To do so, we have divided the study period into three intervals (from 1995 to 2009) based on China’s three most-recent 5-year plans. We then divided China’s 30 provinces into four categories based on the individual and net effects of these factors on carbon emissions. On this basis, we discuss potential strategies for reducing China’s carbon emissions. Increasing GDP caused the largest increase in carbon emissions, whereas decreasing energy intensity significantly decreased emissions. Changes in the economic structure increased emissions, with the economic structure becoming more carbon-intensive; efforts to optimize the fuel mix slightly decreased emissions during the first and third periods, but increased emissions during the second period. Our analysis also revealed differences between provinces and regions, allowing local managers to focus on the most important problems for their area. To reduce future energy-related carbon emissions, China’s economic structure, energy intensity, and fuel mix must all be improved.
In this paper, stormwater runoff from an urban traffic road and building located in Beijing, China, was characterized to measure the stormwater runoff discharge rates and pollutant concentrations. Based on monitoring,...
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In this paper, stormwater runoff from an urban traffic road and building located in Beijing, China, was characterized to measure the stormwater runoff discharge rates and pollutant concentrations. Based on monitoring, the runoff water quality on two underlying surface conditions was analyzed. The temporal dynamics of chemical oxygen demand (COD), NH 3- N, NO 3 -N and total phosphorus (TP) were similar and the concentration dropped quickly in the first half hour. The initial concentration of COD, NH 3 -N, NO 3 -N and TP are worse than the fifth category of national surface water standard, some of them were even beyond the standard of the third category of emission discharge standard. In the urban water resource conservation, reuse of stormrain is a good potential. So, a simple combination of treatment methods with Quartz sand and activated carbon was proposed to reduce the pollution concentration. The COD and TP concentration decreased significantly after the treatment, and the removal rate is sensitive to the hydrological loading of inlet water. The activated carbon did not have impact on NH 3 -Nand NO 3 -N and the removal rate is stable on three kinds of hydrological scenarios. The study demonstrates the discharge characteristics of urban sotrmrain runoff and provides the results of simple and cheap treatment equipment.
Emergy analysis provides a feasible approach to evaluate the status and position of different energy carriers in the universal energy hierarchy. In this paper, an emergy-based method is conducted to measure the resour...
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Emergy analysis provides a feasible approach to evaluate the status and position of different energy carriers in the universal energy hierarchy. In this paper, an emergy-based method is conducted to measure the resources input of Chinese industry from 1997 to 2006. Resources inflows including fossil fuels, mineral resources, agricultural products, and other imported materials are accounted, based on which related indicators including resources intensity, industrial output, and environmental emissions are investigated. Results show a steady upward trend for the total resources input of Chinese industry during the past decade. The total resources input amounted to 1.53×1025 sej in 2006, of which non-renewable one accounted for 70.65% owing to the dominating input of fossil fuels and nonmetal minerals. Resources intensity measured by the ratio of resources input to industrial value added declined gradually during 1997–2002, but the rapid expansion of resource–intensive sub–sectors resulted in a reverse trend since 2003. The current resources use pattern of Chinese industry is characterized by increasing input of non-renewable resources, excessive expansion of resource–intensive production, and tremendous challenge from environmental pressure.
In order to provide a theoretical support to operation and management for a wastewater treatment plant which wastewater is mixed with domestic sewage and industrial wastewater, some sludge activity or specific oxygen ...
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In order to provide a theoretical support to operation and management for a wastewater treatment plant which wastewater is mixed with domestic sewage and industrial wastewater, some sludge activity or specific oxygen ...
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In order to provide a theoretical support to operation and management for a wastewater treatment plant which wastewater is mixed with domestic sewage and industrial wastewater, some sludge activity or specific oxygen uptake rate (SOUR) impact factors such as temperature, pH, MLSS and hazardous chemicals etc. are researched on bio-treatment system in a wastewater treatment plant in Jiangnan. It is showed that: 1) at 30 °C or at pH 8, SOUR is maximum when other factors are same; 2) SOUR of activated sludge slightly decreases with the increase of MLSS;3) SOUR is significantly affected by hazardous chemicals. Activated sludge shows strong inhibitive ability to hazardous chemicals with higher MLSS. For example, when MLSS is 1206 mg/L and 723 mg/L, the inhibitory concentration 50% of phenol is 15.8 mg/L and 4.2 mg/L respectively.
Wetlands research and restoration has become one of the critical concern due to their importance in providing ecosystem services. This study proposes a holistic methodology to assess the wetland ecosystem based on cos...
Wetlands research and restoration has become one of the critical concern due to their importance in providing ecosystem services. This study proposes a holistic methodology to assess the wetland ecosystem based on cosmic exergy as a thermodynamic orientor. This new approach is applied to two typical wastewater treatment facilities (an activated sludge system and a cyclic activated sludge system) and to a constructed wetland ecosystem in Beijing for comparison. Results show that the Beijing wetland ecosystem gains positive net present ecological value of 3.08E+14 J c regarding its total life cycle. Comparison with the activated sludge system and cyclic activated sludge system, shows that the wetland ecosystem has greater dependencies on local resources (22% vs. 0% vs. 0%) and renewable resources (67% vs. 38% vs. 31%) as well as a larger ecological sustainability index (0.64157 vs. 0.00005 vs. 0.00008). This implies that the wetland ecosystem is more environmentally friendly and sustainable method for water treatment .
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