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471.
Kate Smith Shuming Liu Yi Liu Dragan Savic Gustaf Olsson Tian Chang Xue Wu 《Mitigation and Adaptation Strategies for Global Change》2016,21(8):1213-1233
To reduce greenhouse gas (GHG) emissions and help mitigate climate change, urban water systems need to be adapted so that electrical energy use is minimised. In this study, energy data from 2011 was used to quantify energy use in China’s urban water supply sector. The objective was to calculate the energy co-benefits of urban water conservation policies and compare energy use between China and other countries. The study investigated influencing factors with the aim of informing the development of energy efficient urban water infrastructure. The average energy use per cubic metre and per capita for urban water supply in China in 2011 was 0.29 kWh/m3 and 33.2 kWh/cap year, respectively. Total GHG emissions associated with energy use in the urban water supply sector were 7.63 MtCO2e, or carbon dioxide equivalent. Calculations using these indicators showed significant energy savings could result from water conservation measures. A comparison between provinces of China showed a direct correlation between energy intensity of urban water supply and the population served per unit length of pipe. This may imply energy and emission intensity can be reduced if more densely populated areas are supplied by a corresponding pipe density, rather than by a low-density network operating at higher flow rates. This study also found that while the percentage of electrical energy used for urban water supply tended to increase with the percentage of population served, this increase was slower where water supply was more energy efficient and where a larger percentage of population was already supplied. 相似文献
472.
Removal of nutrients and veterinary antibiotics from swine wastewater by a constructed macrophyte floating bed system 总被引:2,自引:0,他引:2
Qiming Xian Lixia Hu Hancheng Chen Zhizhou Chang Huixian Zou 《Journal of environmental management》2010,91(12):2657-2661
The potential of three varieties of Italian ryegrass (Lolium multiflorum Lam.), Dryan, Tachimasari and Waseyutaka, to improve the water quality of swine wastewater was evaluated using a constructed macrophyte floating bed system. With respect to reductions in levels of nutrients, chemical oxygen demand (COD), and sulfonamide antimicrobials (SAs, including sulfadiazine, sulfamethazine, and sulfamethoxazole), Dryan performed better than Tachimasari and Waseyutaka. For Dryan, total N was reduced by 84.0%, total P by 90.4%, COD by 83.4% and sulfonamide antimicrobials by 91.8–99.5%. Similar results were observed for Tachimasari and Waseyutaka. The results indicated that the treatment of swine wastewater using the constructed macrophyte floating bed system was effective in the removal of nutrients and veterinary antibiotics. 相似文献
473.
This research utilized the Ames test to determine the mutagenicity of water treated by advanced processes, including ozonation and granular activated carbon (GAC). Raw water samples for this research included those obtained from the Pan Hsin waterworks as well as samples containing humic acids. Treated samples were collected from the pilot‐scale advanced treatment plant. The Ames test was used to measure the mutagenicity of the water after each treatment process. For the Pan Hsin raw water samples treated with ozone or GAC, it was indicated that, regardless of whether samples were preozonated or not, they all showed a mutagenic potency less than 2 once the S9 enzyme was added. This level of mutagenicity is insignificant. The prepared humic acid samples, on the other hand, demonstrated a significant reduction in mutagenicity after the pre‐ozonation process, indicating that preozonation can lower the degree of mutagenicity. Furthermore, the mutagenicity of the prepared humic acid samples gradually decreased after the advanced treatment process. However, when chlorine was added later to these samples, the mutagenicity increased again. This research shows that the use of O3/GAC processes to treat water can successfully lower mutagenicity, indicating a great potential for applications in the treatment of drinking water. 相似文献
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This analysis estimates willingness to pay to improve community-based rural water utilities in the Dodoma and Singida Regions of Central Tanzania, using Multinomial Logit functions. An estimate of willingness to pay provides an indication of the demand for improved services and potential for them being sustainable. Surveys were conducted in a total of 30 villages in the two regions. In the Dodoma Region, about 14% of respondents indicated that they were satisfied with the status quo, 64% suggested increasing water discharge and watering points, and 22% proposed other improvements relating to water quality. In the Singida Region, 31% of the respondents were satisfied with the status quo, 59% wanted deeper boreholes and watering points, and 10% indicated other types of improvement relating to water quality. The Multinomial Logit functions indicated that the interaction between the water quality variable and proposed bids were important in making choices with reference to the type of improvement desired. Respondents who wanted to increase water supply in Dodoma Region were willing to pay 32 Tsh above the existing tariff of 20 Tsh/bucket. In the Singida Region, the analogous amount was 91 Tsh per household per year above the existing user fee of 508 Tsh per household per year. If the tariff or user fees have to be increased, the estimated average potential revenue for the surveyed villages was 252 million Tsh/year (US$265 263) in the Dodoma Region, and 5.2 million Tsh/year (US$5474) in the Singida Region. In the future, strategic planning is needed to ensure that improvements proposed potentially improve cost recovery initiatives and increase the level of consumer satisfaction. Also, care will be needed to ensure that more disadvantaged community members do not suffer unduly from increases in tariff or user fees. 相似文献
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477.
J. C. Chuang Y. C. Lan Y. S. Hsu S. L. Chuang S. R. Liaw C. S. Chang 《Chemistry and Ecology》2013,29(1-2):97-104
Abstract This study introduces the principles of KMG's (Kaoshiung Municipal Government) dealing with the non-poisonous urban and industrial waste through reclamation of shore land in reinforcing a sense of coastal protection and land development in Tai-Lin-Pu coastal area, southern Taiwan. Through a series of experimental studies, we found that substitutes of coarse aggregate with a broad spectrum of integrating slag powder, fly ash, and cementitious material can be obtained with a benefit up to 80% saving of cement. the integrated aggregates from the non-poisonous industrial wastes were subsequently made into armour units and used in the field tests at Tai-Lin-Pu coastal area, where the shorelines are seriously eroded. After being subjected to several severe typhoon advents, the results showed that the waste-made units used as the protection breakwater, together with construction wastes and excavated soil as the filling material, prove to be an effective practice in utilizing recycled urban waste to reclaim erosive shore lands. Moreover, this study also demonstrates that through detailed analysis of the waste characteristics, scrap material could be turned into valuable construction aggregates, and highlights the value of non-poisonous urban and industrial waste as a alternative resource for the shore protection engineering. 相似文献
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This study reviews corn–ethanol life cycle assessment studies and modeling tools to identify key discrepancies between studies, and shortcomings in analysis of greenhouse gas emissions. The primary conclusions are that direct land use change modeling, soil N2O emissions modeling, and co-product crediting were either poorly treated or treated inconsistently across most or all studies. Despite the existence of improved methods and tools proposed by institutional bodies and the broader research community, the state of the practice tends towards over-simplified and highly generalized methods that increase potential uncertainty in greenhouse gas estimates and prevents differentiation among producers of corn ethanol. 相似文献