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991.
含硫气田在天然气开采、管道批处理、气田污水处理过程中,由于高压气流携带井底岩屑、单质硫析出、工艺添加的化学药剂反应产生沉淀物等因素,会产生一些成分复杂、有恶臭气味的固态物质,统称为采气污泥,影响生产安全和工艺参数调配,需要及时清理并无害化处置。结合固废减量化、无害化、资源化的处置原则,立足于企业自行处置的目的,本文就含硫气田采气污泥特性以及无害化处理的方法进行研究,对处理效果进行了分析,对废物综合利用进行了有益的尝试,为今后含硫气田污泥处理提供了一条可借鉴的思路。  相似文献   
992.
建立了简便、快速、有效的分散液液微萃取(DLLME)-气相色谱/质谱技术萃取水样中痕量阿特拉津的新方法。通过试验确定最佳萃取条件。  相似文献   
993.
介绍了动力风泵房每年有大量的工业余热为没经过处理直接排放,造成能源的浪费,以及其解决的思路:利用水源热泵吸收动力风泵房中产生的余热来加热水源,变成洗浴用水,从而达到节能减排的目的.  相似文献   
994.
系统介绍了秩相关系数的计算、检验及Excel计算模式,为环境质量报告书的编制及水质趋势变化分析提供了更加方便的方法。  相似文献   
995.
Long-term changes of fish biotic integrity in the Sanmenxia Wetland,North China,since the 1950 s were assessed using the fish index of biological integrity(FIBI). The water and sediment quality was evaluated by the water quality index(WQI) and sediment pollution index(SPI). The results showed that FIBI continuously decreased from 46 to 20 during the past 5 decades,which indicated that the fish community state shifted from fair to very poor conditions,and damming by itself did not affect the fish biotic integrity. At the same time,WQI fell from 83 to 44.1,and SPI increased from 0.99 to 2.14 since the 1960 s,resulting from fast regional socio-economic development and insufficient wastewater treatment. Correlation analysis suggested that water quality significantly affected biotic integrity(r = 0.867,p 〈 0.05) through direct effects on the fish community. As a representative example of many wetlands in North China,our study clearly demonstrated that the biological integrity was degraded,induced both by water quality deterioration and sediment pollution,further driven by the contradiction between rapid development of regional economy and lagging development of sewage treatment facilities,which were thought to be the main factor responsible for the degradation of biological integrity.  相似文献   
996.
What factors explain stakeholders’ perceptions of scientists in environmental politics? Questionnaire data are used to examine stakeholders’ views of scientific experts in the context of Lake Tahoe environmental policy from 1984 to 2001. Stakeholders’ perceptions of scientists have remained the same over time – despite a shift from adversarial to collaborative policymaking and after decades of mounting scientific evidence showing water quality declines. On average, stakeholders perceive scientists with limited influence on Lake Tahoe environmental policy and view them with mixed levels of skepticism. Stakeholders’ evaluation of scientists is best explained by their beliefs about development versus the environment. Stakeholders in favor of more land development express distrust of scientists and negatively evaluate university researchers and consultants. Stakeholders in favor of environmental protection are more likely to trust scientists and positively evaluate university researchers and consultants.  相似文献   
997.
The performance of different policy design strategies is a key issue in evaluating programmes for water quality improvement under the Water Framework Directive (60/2000). This issue is emphasised by information asymmetries between regulator and agents. Using an economic model under asymmetric information, the aim of this paper is to compare the cost-effectiveness of selected methods of designing payments to farmers in order to reduce nitrogen pollution in agriculture. A principal-agent model is used, based on profit functions generated through farm-level linear programming. This allows a comparison of flat rate payments and a menu of contracts developed through mechanism design. The model is tested in an area of Emilia Romagna (Italy) in two policy contexts: Agenda 2000 and the 2003 Common Agricultural Policy (CAP) reform. The results show that different policy design options lead to differences in policy costs as great as 200–400%, with clear advantages for the menu of contracts. However, different policy scenarios may strongly affect such differences. Hence, the paper calls for greater attention to the interplay between CAP scenarios and water quality measures.  相似文献   
998.
The purpose of this study is to develop a model for optimal nonpoint source pollution control for the Fei-Tsui Reservoir watershed in Northern Taiwan. Several structural best management practices (BMPs) are selected to treat stormwater runoff. The complete model consists of two interacting components: an optimization model based on discrete differential dynamic programming (DDDP) and a zero-dimensional reservoir water quality model. A predefined procedure is used to locate suitable sites for construction of various selected BMPs in the watershed. In the optimization model, the objective function is to find the best combination of BMP type and placement, which minimizes the total construction and operation, maintenance, and repair (OMR) costs of the BMPs. The constraints are the water quality standards for total phosphorus (TP) and total suspended solids (TSS) concentrations in the reservoir. A zero-dimensional reservoir water quality model of the Vollenweider type is embedded in the optimization framework to simulate pollutant concentrations in Fei-Tsui Reservoir. The resulting optimal cost and benefit of water quality improvement are depicted by the model-derived trade-off curves. The modeling framework developed in the present study could be used as an efficient tool for planning a watershed-wide implementation of BMPs for mitigating stormwater pollution impact on the receiving water bodies.  相似文献   
999.
Annual water storage in a 5.3 ha, polyethylene-lined, off-stream irrigation reservoir in northern Alabama, USA, resulted in marked improvement in water quality. Results of three-year monitoring from June 1999 to May 2002 indicate that the relatively static conditions of the reservoir enhanced settling of suspended particles by 85% (from 14.4 to 2.1 mg TSS/L) that cleared the water and increased sunlight penetration. The organic and inorganic particles that settled to the bottom removed up to 88% of the nutrients and other chemical substances from the water. Nutrients remaining in the water column were rapidly assimilated by phytoplankton algae. With the basin sealed at the bottom and no runoff input there was limited opportunity for nutrients or other substances to enter the reservoir in quantities that would adversely affect water quality. Consequently, reservoir water was found to be of high quality and suitable as a raw water supply. Non-traditional, off-stream storage reservoirs such as described in this paper may be uniquely suited for agricultural irrigation and public water supply in regions such as southeastern US that experience relatively frequent drought conditions but have relatively abundant long-term annual rainfall.  相似文献   
1000.
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