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In this paper, emergy accounting (EA) and life cycle assessment (LCA) methods are employed to investigate a typical urban wetland park, the Green Lake Urban Wetland Park (GLUWP) of Beijing, in terms of its environmental and capital inputs, ecosystem services and organic matter yields, environmental support, and sustainability. The LCA method is also used to obtain a quantitative estimation of the environmental impact of discharges during the entire life cycle of the GLUWP. Various emergy-based indices, such as emergy yield ratio (EYR), environmental load ratio (ELR), emergy sustainability index (ESI), net economic benefit (Np), and environmental impacts of process-based LCA, including global warming potential (GWP), eutrophication (EU), nonrenewable resource depletion (RU), energy consumption (EN), acidification potential (AP), photochemical oxidant creation potential (POCP), particulate matter (PM) and wastes (W), are calculated. The results show that the GLUWP has higher proportions of renewable resource input, less pressure on the environment, more environmental support and better ecological and economic benefits, which can be considered as an environment-friendly and long-term sustainable ecological practice, compared with another constructed wetland in Beijing. Meanwhile, the dominant environmental impact is induced by POCP with the construction phase contributing the most on the entire life cycle. It is expected that increasing green area, extensively using environment-friendly materials, optimizing construction techniques and reducing power consumption can promote the sustainability of the GLUWP. [Copyright &y& Elsevier]

Abstract: In this paper, aerobic biological filter is applied to treat swine farms wastewater. Laboratory experiments are conducted to confirm the optimum parameters for start-up and operation of filter by investigating the effect of temperature on the start-up of the filter and the influence of temperature, pH value and recirculation rate on the treatment effect of the filter. The results show temperature increasing is benefit for accelerating start-up of filter in the range of 17.0-33.0°C. COD removal of the filter enhances slightly by temperature rising during normal operation. High NH3-N reduction (above 84.0%) is obtained in range of 25.0-30.0°C. pH in range of 7.1-8.0 is recommended for operation treatment, in which pollutants reduction for COD and NH3-N is 85.7%-86.9 and 86.8%-89.5%, respectively. COD and NH3-N reduction enhances with recirculation rate increasing. When the recirculation rate is above 4, the increasing of COD and NH3-N reduction is slight. Swine wastewater treatment project utilizing aerobic biological filter as a key element is established in a swine breeding farm of Daxing district, Beijing. The whole project runs well by start-up and operation of filter. COD reduction of wastewater in aerobic biological filter is 63.0-89.3%. And the COD concentration of effluent in filter is below 150mg/L, which achieves the national requirement of pollutants output standard of livestock and poultry breeding industry and water quality standard of farmland irrigation. The aerobic biological filter is worth to be generalized for treating swine wastewater in China. [ABSTRACT FROM AUTHOR]