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501.
502.
选取废水、挥发酚、氰化物、COD、石油类和氨氮为中国工业水污染指标,利用分解分析方法将2004—2010年间的污染变化分解为规模效应、结构效应、污染治理效应、清洁技术效应和广义技术效应。结果显示,这5类效应的平均作用强度分别为2.08%、3.04%、15.61%、17.37%和32.88%,其中规模效应和广义技术效应是影响工业水污染的主导效应。各类效应对不同污染物的作用方向并不完全一致,规模效应促进污染物排放量的增加;结构效应以加重污染为主,污染治理效应和清洁技术效应以减轻污染为主;广义技术效应的平均作用强度和负向作用概率均最大,是现阶段中国工业水污染控制最为有效的手段。 相似文献
503.
强化垂直流可渗透反应墙处理渗滤液污染物 总被引:1,自引:0,他引:1
针对垃圾渗滤液污染物组分多、处理难度大、可生化性差的特点,基于可渗透反应墙(PRB)被动修复技术,通过多种填料的组合构建三重垂直流PRB强化的砂箱模型,对垃圾渗滤液进行连续动态处理研究。实验结果表明,填料的组合顺序对强化PRB系统净化能力有较大的影响,由无烟煤、沸石、钢渣依次组成的强化垂直流PRB系统(2#砂箱)对NH+4-N、NO-3-N、NO-2-N、COD、PO3-4-P的平均去除率分别为96.12%、30.36%、75.24%、39.03%和30.47%,处理效果明显好于相同条件下依次由无烟煤、钢渣、沸石组成的强化垂直流PRB系统(1#砂箱)。与常规PRB处理系统相比,强化垂直流可渗透反应墙系统可实现垃圾渗滤液中多种污染物同步有效去除,是极具发展潜力的新型技术。 相似文献
504.
Dae-Woon Jeong Won-Jun Jang Jae-Oh Shim Won-Bi Han Kyung-Won Jeon Yong-Chil Seo Hyun-Seog Roh Jae Hoi Gu Yong Taek Lim 《Journal of Material Cycles and Waste Management》2014,16(4):650-656
A comparative study on Fe/Al, Fe/Al/Cu, and Fe/Al/Ni catalysts in high-temperature water–gas shift reaction (HT–WGS) using simulated waste-derived synthesis gas has been carried out. The metal oxide (Cu and Ni) and aluminum incorporated Fe catalysts were designed to get highly active HT–WGS catalysts. Despite the high CO concentration in the simulated waste-derived synthesis gas, Fe/Al/Cu catalyst exhibited the highest CO conversion (84 %) and 100 % selectivity to CO2 at a very high gas hourly space velocity (GHSV) of 40,057 h?1. The outstanding catalytic performance is mainly due to easier reducibility, the synergy effect of Cu and Al, and the stability of the magnetite. 相似文献
505.
Cheol Min Lee Soo Jong Hong Yoon Shin Kim Gee Yong Park Sun Ju Nam Goung Kyung Hwan Kim 《Environmental science and pollution research international》2014,21(2):1146-1152
This research has been conducted continuously since 2009 as part of a cohort of studies examining relationships between asthma and genetic factors, dietary habits, and environmental factors. Based on data from environmental research on house dust mites and endotoxins, which are widely known as pollutants in bedding that cause asthma in pregnant women and children, this work was conducted to obtain basic data that can be used in future cohort studies that analyze links between distribution of biological hazards and physical features of residential environments. The detection rates of house dust mite allergens, Der p1 and Der f1, were 52.7 and 86.5 %, respectively, indicating that Der f1 is a dominant species in domestic indoor environments. According to comparisons between concentrations of house dust mites and endotoxins in bedding of pregnant women and children, Der p1 and endotoxins showed significantly lower concentrations in bedding of pregnant women compared with those in bedding of children, whereas Der f1 showed no significant difference in concentration according to bedding. 相似文献
506.
Rongfei Zhang Dongsheng Jiang Liujun Zhang Yibin Cui Mei Li Lin Xiao 《Environmental science and pollution research international》2014,21(3):2141-2153
This paper's survey of the pollution of the Wujin'gang River is important because it is one of the main rivers flowing into Meiliang Bay of Lake Taihu in eastern China. Trace metals (TMs) in this paper are described according to their pollution index (P i). Cluster analysis and correlation analysis are utilized for group sites and to assess co-contamination. Toxicity effect analysis was conducted using individual sediment quality guideline quotients (SQGQs) and mean SQGQs. The results showed that sediment from the Wujin'gang River basin was affected by nutrients, heavy metals, and polycyclic aromatic hydrocarbons (PAHs), which are an essential contamination source for both Meiliang Bay and Zhushan Bay of Lake Taihu. The discharge of TMs has significant correlations to total nitrogen (TN) and total phosphorus (TP); however, no significant correlations were observed between the content of PAHs and TMs. Toxicity effect results show that sediment in the Wujin'gang River basin threatens sediment-dwelling organisms. The harmful effect was mainly caused by heavy metals especially Cd, Cr, Ni, and Cu. Sediment dredging is an effective way to control pollution from internal rivers especially for the pollution of TN and heavy metals in the Wujin'gang River basin. 相似文献
507.
Xi-Kui Wang Xia-Jie Jiang Yi-Nan Wang Jing Sun Chen Wang Ting-Ting Shen 《Environmental science and pollution research international》2014,21(11):7065-7074
Occurrence, distribution, spatial and seasonal variations, and partitioning between aqueous phase and suspended particulate matters (SPM) of triclocarban (TCC) and triclosan (TCS) in Xiaoqing River, which receives wastewater treatment plant (WWTP) effluents, were studied. The distribution of the total TCC and TCS levels in surface water and sediments along the river were discussed. The highest TCC and TCS concentrations were both found near the discharge port of WWTPs, and the TCC and TCS levels decreased downstream of the WWTPs as a result of their distances from the source of WWTP discharges. The mean values of TCC and TCS in low-flow season were 1.62 and 1.80 times, respectively, as much as in high-flow season in surface water. The study on partitioning of TCC and TCS between aqueous phase and SPM shown the mean level of dissolved TCC accounted for about 10 % of the total level in surface water, whereas the TCS level was about 30 %. The TCC concentrations detected in the surface sediment samples (0 to 5 cm) ranged from 226 to 1,956 ng/g, with a mean value of 733 ng/g. The TCS levels were between 85 and 705 ng/g, with a mean value of 255 ng/g. The distribution and variations of TCC and TCS in sediments along the river were highly consistent with those in the water phase. The TCC and TCS levels in deep sediments (5 to 10 cm) were significantly lower than those in surface sediments. The mean TCC level in surface sediments was about 2.4 times as much as in deep sediments, and the TCS level in surface sediments was 3.1 times as much as in deep sediments. 相似文献
508.
Defu Xu Yinjuan Wu Yingxue Li Alan Howard Xiaodong Jiang Yidong Guan Yongxia Gao 《Environmental science and pollution research international》2014,21(17):10108-10119
A surface- and vertical subsurface-flow-constructed wetland were designed to study the response of chlorophyll and antioxidant enzymes to elevated UV radiation in three types of wetland plants (Canna indica, Phragmites austrail, and Typha augustifolia). Results showed that (1) chlorophyll content of C. indica, P. austrail, and T. augustifolia in the constructed wetland was significantly lower where UV radiation was increased by 10 and 20 % above ambient solar level than in treatment with ambient solar UV radiation (p?0.05). (2) The malondialdehyde (MDA) content, guaiacol peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activities of wetland plants increased with elevated UV radiation intensity. (3) The increased rate of MDA, SOD, POD, and CAT activities of C. indica, P. australis, and T. angustifolia by elevated UV radiation of 10 % was higher in vertical subsurface-flow-constructed wetland than in surface-flow-constructed wetland. The sensitivity of MDA, SOD, POD, and CAT activities of C. indica, P. austrail, and T. augustifolia to the elevated UV radiation was lower in surface-flow-constructed wetland than in the vertical subsurface-flow-constructed wetland, which was related to a reduction in UV radiation intensity through the dissolved organic carbon and suspended matter in the water. C. indica had the highest SOD and POD activities, which implied it is more sensitive to enhanced UV radiation. Therefore, different wetland plants had different antioxidant enzymes by elevated UV radiation, which were more sensitive in vertical subsurface-flow-constructed wetland than in surface-flow-constructed wetland. 相似文献
509.
510.
以成都粘土为原料,十六烷基三甲基溴化铵(HDTMA)为改性剂制备有机改性土,并将其应用于垃圾渗滤液的预处理。采用单因素静态吸附实验,以粘土对垃圾渗滤液COD和氨氮的去除率作为考查指标,初步探究有机改性土预处理垃圾渗滤液的适宜条件;并对有机改性粘土及原土进行性能表征,初步分析其吸附机理。研究结果表明,有机土的处理效果明显优于原土,处理效果上比原土提高了1.6~2.3倍;有机土预处理垃圾渗滤液适宜条件为:投加量120 g/L、搅拌速度200 r/min、搅拌时间50 min、pH=7、静置时间为6 h。 相似文献