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411.
固液分离法处理废钻井液的实验研究 总被引:3,自引:1,他引:2
废钻井液对环境的污染是一个难以解决的问题。针对塔里木油田的地质情况,使用固液分离法对部分废钻井液样品进行了实验研究工作。固液分离法采用两次处理工艺流程。即先经一级初步絮凝处理和强化离心分离,使大部分固相去除,然后对脱出的废液进行第二级絮凝处理后即可达到排放要求。实验结果表明:固液分离法能够将废钻井液分离成固-液两相,其液相能够达到排放要求,固相残渣对环境污染程度大幅度降低甚至无污染;若将此处理法同其它方法相结合,如坑内密封法、固化法等相结合会得到更满意的环保效果。 相似文献
412.
Xiang Li Haohui Kong Xinying Zhang Bin Peng Cong Nie Guanglin Shen Huimin Liu 《环境科学学报(英文版)》2014,26(4):827-833
Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor (ELPI) to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters (D, geometric mean of a channel) of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles. 相似文献
413.
莱州湾南岸咸水入侵区生态环境分区与生态恢复研究 总被引:1,自引:0,他引:1
本文在对莱州湾南岸咸水入侵区进行区域生态分析的基础上,对研究区进行了生态环境分区,提出了研究区环境战略调整和综合治理咸水入侵灾害的关键性技术措施,并结合各分区特点,有针对性地提出了各生态环境分区生态恢复和重建的组合配套措施。 相似文献
414.
我国人居环境现状和改善对策 总被引:1,自引:0,他引:1
本文分析了我国人类环境现状及面临的主要问题,提出了改善人居环境的对策,研究制定法规政策和发展规划、计划,并切实实施,把住宅建设和城市基础设施建设放在重要位置,加强科技工作和国际合作工作。 相似文献
415.
Yifeng Xue Yong Wang Xuefeng Li Hezhong Tian Lei Nie Xiaoqing Wu Junrui Zhou Zhen Zhou 《环境科学学报(英文版)》2018,30(3):29-42
The mass concentration and major chemical components of fine particulate matter were measured before, during and after Beijing''s massive parade commemorating 70th anniversary of the Chinese Victory in World War II on September 3, 2015. Regional emission inventory, positive matrix factorization (PMF), observations from space and backward air mass trajectories were jointly applied to identify the major pollution sources and their temporal and spatial variations. The contributions of emissions, their variations and the meteorological conditions related to the “parade blue” phenomenon in Beijing and its surrounding areas were investigated in detail. The main cause of the decreased PM2.5 mass concentration was attributed to the absolute reduction in emissions of primary air pollutants. The chemical composition of PM2.5 varied significantly before, during and after the parade. Fugitive dust particles were well controlled, the secondary formation of PM2.5 was reduced along with the controlled gaseous precursors'' emissions from vehicles and industrial sources during the temporary intensified control period. During the parade period, the SO2 and NO2 column concentrations in Beijing and the surrounding areas decreased sharply, indicating that the coordinated reduction in primary emissions from the surrounding areas of Beijing played an important role in lowering the ambient concentration of SO2 and NO2 and accordingly lowered PM2.5 and improved the regional air quality. A comparison of the temperature, humidity, and wind speed and direction during the same periods in 2014 and 2015 showed that the meteorological conditions positively influenced the achievement of “parade blue”. 相似文献
416.
Weifang M Jiaji Sun Yangyao Li Xiaoxiu Lun Dan Shan Chao Nie Miaomiao Liu 《环境科学学报(英文版)》2018,30(2):51-61
This study investigated 17α-ethynylestradiol(EE2) biodegradation process and primary metabolic pathways associated with community structures of microorganism during groundwater recharge using reclaimed water. The attenuation rate is 1.58 times higher in wetting and drying alternative recharge(WDAR) than in continual recharge(CR). The primary biotransformation pathways of EE2 in WDAR system began with the oxidation of C-17 on ring D to form a ketone group, and D-ring was subsequently hydroxylated and cleaved. In the CR system, the metabolic pathway changed from the oxidation of C-17 on ring D to hydroxylation of C-4 on ring A, and ring A or B subsequently cleaved; this transition was related to DO, and the microbial community structure. Four hundred fifty four pyrosequencing of 16 s r RNA genes indicated that the bacterial communities in the upper layer of the WDAR system were more diverse than those found in the bottom layer of the CR system; this result was reversed for archaea. Unweighted Uni Frac and taxonomic analyses were conducted to relate the change in bacterial community structure to the metabolic pathway. Microorganism community diversity and structure were related to the concentrations of dissolved oxygen, EE2 and its intermediates in the system. Five known bacterial classes and one known archaeal class, five major bacterial genera and one major archaeal genus might be involved in EE2 degradation. The findings of this study provide an understanding of EE2 biodegradation in groundwater recharge areas under different recharging modes and can facilitate the prediction of the fate of EE2 in underground aquifers. 相似文献
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420.
Sheng-Wei Nie Wang-Sheng Gao Yuan-Quan Chen Peng Sui A. Egrinya Eneji 《Journal of Cleaner Production》2010,18(15):1530-1534
Using the life cycle assessment (LCA) method, we analyzed the effects of different cropping systems (sole maize (CK), maize + soybean (CST) and maize + groundnut (CGT)) on the environment. The comprehensive index of environmental impacts varied in the order, sole maize > maize + groundnut > maize + soybean, with corresponding intercropping values of 0.1295, 0.1229 and 0.0945, respectively. The results showed that intercropping maize with suitable plants (e.g., groundnut and soybean) could reduce the adverse effects of over-application of nitrogen fertilizer on the environment. The study further showed that the LCA method may be a convenient and effective approach for analyzing the environmental impact of fertilizer management in agricultural fields. 相似文献