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931.
在油气田开发生产过程中,会产生大量危险废物,如处置不当会造成严重污染,但如何判别危险废物是环境管理中的难点问题。文章分析了石油和天然气开采业生产工艺流程,对石油和天然气开采业的油井、联合站、集输管道产生危险废物的类型、环节进行了分析,可为有关人员对危险废物判定提供参考。 相似文献
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油田压裂废液处理及回注实验 总被引:1,自引:1,他引:0
油田压裂废液具有高COD、高悬浮物等特点,处理达标难度大。以悬浮固体含量、悬浮固体颗粒粒径中值和含油量为指标,实验研究了混凝、微滤膜过滤技术参数,最佳条件为:絮凝剂投加量800~1 000mg/L,助凝剂投加量9~10mg/L,快速搅拌G值250~300s--1,慢速搅拌G值约50s--1,经50、10μm两级微滤膜过滤后悬浮固体含量、粒径中值、含油量满足SY/T 5329-2012《碎屑岩油藏注水水质指标及分析方法》标准要求。该方法工艺简单,成本低,在一定程度上解决了压裂废液难处理的问题。 相似文献
934.
文章介绍了红浅稠油污水处理站采用的"离子调整旋流反应+216t/h软化水"处理工艺,该工艺创新性的采用了分置式反应罐,将混凝、反应、加药、沉降、颗粒吸附有机结合,优选出高效的污水处理药剂,首次在新疆油田公司污水处理工艺中应用改性纤维束过滤器和216t/h软化水处理装置,优化了各节点的配套工艺,使处理后的污水水质达到回用锅炉水质标准,取得了良好的效果。同时,通过对加药浓度、隔油、反冲洗周期等参数优化,保证了红浅稠油污水回用锅炉处理系统的平稳运行,累计处理回用污水约730万m3,有效地节约了水资源,保护了环境,综合效益显著。 相似文献
935.
The diurnal atmospheric phosphine (PH3) concentrations and fluxes at the water-air interface in Lake Taihu were reported. The results showed that the PH3 flux at the water-air interface ranged from −69.9 ± 29.7 to 121 ± 42 ng m−2 h−1, with a mean flux of 14.4 ± 22.5 ng m−2 h−1. The fluxes were both negative and positive during the diurnal period, indicating that the lake can act as a sink and a source of PH3. In addition, the PH3 fluxes were positively correlated with water temperature, total soluble phosphorus and soluble reactive phosphorus, while they were negatively correlated with water redox potential. A similar diurnal variation curve of atmospheric PH3 concentrations was observed during all four seasons, with the maximum level occurring in early morning and the minimum appearing around midday. These findings suggest that light plays an important role in the elimination of atmospheric PH3. A significant positive correlation was also found between air temperature and atmospheric PH3 concentration. The mean flux of PH3 in Lake Taihu was higher than in other reported wetlands, with an estimated annual emission of PH3 to the atmosphere of 2.94 × 105 g y−1. 相似文献
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939.
Assessment for Salinized Wasteland Expansion and Land Use Change Using GIS and Remote Sensing in the West Part of Northeast China 总被引:6,自引:0,他引:6
Li X Wang Z Song K Zhang B Liu D Guo Z 《Environmental monitoring and assessment》2007,131(1-3):421-437
Due to human impact under climatic variations, western part of Northeast China has suffered substantial land degradation during
past decades. This paper presents an integrated study of expansion process of salinized wasteland in Da’an County, a typical
salt-affected area in Northeast China, by using Geographic Information Systems (GIS) and remote sensing. The study explores
the temporal and spatial characteristics of salinized wasteland expansion from 1954 to 2004, and land use/cover changes during
this period. During the past 50 years, the salinized wasteland in study area have increased by 135,995 ha, and in 2004 covers
32.31% of the total area, in the meantime grassland has decreased by 104,697 ha and in 2004 covers only 13.15% of the study
area. Grasslands, croplands and swamplands were found the three main land use types converted into salinized wasteland. Land
use/cover changes shows that between 1954 and 2004, 48.6% of grasslands, 42.5% of swamplands, and 14.1% of croplands were
transformed into salinized wasteland, respectively. Lastly, the major factors influencing salinized wasteland expansion and
land use/cover changes were also explored. In general, climatic factors supplied a potential environment for soil salinization.
Human-related factors, such as policy, population, overgrazing, and intensified and unreasonable utilization of land and water
resources are the main causes of salinized wasteland expansion. 相似文献
940.
Liu Y Kong GT Jia QY Wang F Xu RS Li FB Wang Y Zhou HR 《Journal of environmental science and health. Part. B》2007,42(2):219-227
This study was conducted to investigate the effects of soil properties on the heavy metal accumulation in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) at the field scale. The concentrations of cadmium (Cd), mercury (Hg), and chromium (Cr) in topsoil and vegetable samples from Nanhai district of Foshan city in the Pearl River Delta (PRD) were analyzed. The results showed that 56.5% of the soil samples exceeded the grade II of the Chinese Soil Environmental Quality Standard (GB 15618-1995) for Hg concentrations, while 8.70% and 17.4% of the vegetable samples exceeded the criteria of the Chinese Safety Qualification of Agricultural Products (GB 18406.1-2001) for Cd and Hg concentrations, respectively. The calculated bio-concentration factor (BCF; i.e., the ratio of the metal concentration in the edible parts of flowering Chinese cabbage to that in soil) values were ranked as: Cd (0.1415) > Cr (0.0061) > Hg (0.0012) (p < 0.01), which demonstrated that Cd was easier to be accumulated in the edible parts of flowering Chinese cabbage than Hg and Cr. Furthermore, the following relationships between (bio-concentration factor) BCF values (BCFs) and soil physicochemical properties were concluded from our results: i) the mean BCFs of coarse-textured soils were higher than those of fine-textured soils; ii) the BCFs decreased with increasing soil pH; iii) the soils with high organic matter(OM) and Cation exchange capacity (CEC) have low BCFs, resulting from their high sorption capacities for Cd, Hg, and Cr. The stepwise linear multiple regression analyses showed that total metal concentrations and available calcium in soils were two main factors controlling the accumulation of Cd, Hg, and Cr in the flowering Chinese cabbage. 相似文献