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111.
矿物法--环境污染治理的第四类方法 总被引:26,自引:0,他引:26
总结介绍了近10年开展环境矿物材料研究所取得的较为系统的研究成果。新提出环境矿物材料基本性能,包括矿物表面效应、孔道效应、结构效应、离子交换效应、结晶效应、溶解效应、水合效应、氧化还原效应、半导体效应、纳米效应及矿物生物交互效应等。展示环境矿物材料开发应用方面的崭新成就,包括利用天然铁的硫化物矿物强还原性,发明一步法还原Cr(Ⅵ)与沉淀Cr(Ⅲ)废水处理新工艺;利用天然锰的氧化物矿物强氧化性,发明处理高浓度与强污染的印染和酚类废水新方法;利用天然钛的氧化物矿物日光催化性,发明光催化降解卤代有机污染物新方法;利用天然蛭石高温脱水膨胀热效应,发明能大幅度提高型煤固硫率与除尘新方法;利用天然钙基蒙脱石低成本制备出同时防止水体与无机和有机污染物渗漏的自愈性强的填埋场衬层建造用新型防渗材料,发明生活垃圾尤其是危险废物填埋场衬层建造新工艺;发现凝灰岩与花岗岩中长石类矿物发育有良好的孔道结构,核素进入可发生固定化作用,成为有效阻滞核素迁移的天然屏障;利用天然纳米管状纤蛇纹石成功制备二氧化硅纳米管,接枝有机物可由亲水性变为疏水性;利用黄钾铁矾的胶体特征作为多金属矿山废石堆隔离防渗层,防止金属硫化物矿物氧化分解与矿山酸性废水污染等。着重指出今后环境矿物? 相似文献
112.
Arsenic is present in groundwater at Siliguri–Jalpaiguri area, West Bengal, India. This is the place where Tista river descending
from the Himalayas meets the alluvial plain. The area represents alluvial fan and floodplains of Tista, Mahananda-Balasan,
Jaladhaka and its tributaries. In the river sediment samples, para- and ferro-magnetic minerals within 0.3–0.05 mm fraction
contain 9–80 ppm of arsenic. The study indicates that iron bearing minerals viz. biotite, hornblende as well as iron coated
grains of the sediment are major contributors towards arsenic budget. Though magnetite as a mineral shows maximum arsenic
content (22 ppm), it is volumetrically not of much significance. Measurement of groundwater collected from tube wells shows
up to 0.05 ppm of arsenic. These arsenic contaminated tube wells occur in a linear fashion along the course of the rivers.
Moreover, localization of contaminated tube wells coincides with the change of channel gradient as observed in longitudinal
section. The study enumerates a cause–effect relationship of arsenic occurrence with river gradient and fluvial sedimentation. 相似文献
113.
In horizontally layered soils of different electrical properties, electrical potential distribution becomes complex and the
obtained resistivity data may be limited in reflecting the actual soil profile. Thus the objective of this study was to identify
the factors that affect resistivity measurement on the cone penetrometer and further investigate the sensitivity of measured
resistivity to different types and concentrations of contaminants at the subsurface level. First, a theoretical resistivity
equation was derived to provide a means of computing the geometric factor. The effective volume of measurement on the cone
penetrometer was investigated and laboratory soil box tests verified the dominance of partially high resistivity regions within
the effective volume of measurement over the apparent resistivity. Such effect was found to lead to possible discrepancies
between the recorded resistivity data and the actual depth of measurement. Measurements on contaminated soil layers indicated
that resistivity cones are efffective in delineating inorganic contaminants in soils of high water contents, and detecting
NAPLs floating above the groundwater table provided that soils adjacent to the plume are not dry of water.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
114.
Manish Kumar Bhawna Sharma AL. Ramanathan M. Someshwar Rao Bhishm Kumar 《Environmental Geology》2009,56(6):1171-1181
Present study is an effort to distinguish between the contributions of natural weathering and anthropogenic inputs towards
high salinity and nutrient concentrations in the groundwater of National Capital Territory (NCT) Delhi, India. Apart from
the source identification, the aquifer of entire territory has been characterized and mapped on the basis of salinity in space
and water suitability with its depth. Major element chemistry, conventional graphical plots and specific ionic ratio of Na+/Cl−, SO4
2−/Cl−, Mg2+/Ca2+ and Ca2+/(HCO3
− + SO4
2−) are conjointly used to distinguish different salinization sources. Results suggest that leaching from the various unlined
landfill sites and drains is the prime cause of NO3
− contamination while study area is highly affected with inland salinity which is geogenic in origin. The seasonal water level
fluctuation and rising water level increases nutrients concentration in groundwater. Mixing with old saline sub-surface groundwater
and dissolution of surface salts in the salt affected soil areas were identified as the principle processes controlling groundwater
salinity through comparison of ionic ratio. Only minor increase of salinity is the result of evaporation effect and pollution
inflows. The entire territory has characterized into four groups as fresh, freshening, near freshening and saline with respect
to salinity in groundwater. The salinity mapping suggests that in general, for drinking needs, groundwater in the fresh, freshening
and near freshening zone is suitable up to a depth of 45, 20 and 12 m, respectively, while the saline zones are unsuitable
for any domestic use. In the consideration of increasing demand of drinking water in the area; present study is vital and
recommends further isotopic investigations and highlights the need of immediate management action for landfill sites and unlined
drains. 相似文献
115.
Contamination,chemical speciation and vertical distribution of heavy metals in soils of an old and large industrial zone in Northeast China 总被引:5,自引:0,他引:5
Fayun Li Zhiping Fan Pengfei Xiao Kokyo Oh Xiping Ma Wei Hou 《Environmental Geology》2009,57(8):1815-1823
Heavy metal pollution of soils has become a major concern in China as a consequence of rapid urbanization and industrialization
in recent years. However, the evaluation on soil heavy metal pollution in Shenyang, the largest heavy industrial base city
in China, has not yet been conducted. In this study, accumulation, chemical speciation, and vertical distribution Cu, Zn,
Pb and Cd in soils were studied and pollution condition was assessed in Tiexi Industrial District of Shenyang, the largest
and oldest industrial zone in Northeastern China. The results showed that in topsoil, the average concentration of total Cu,
Zn, Pb, and Cd was 209.06, 599.92, 470.19 and 8.59 mg kg−1, respectively, much higher than the national threshold limit. The values of pollution index and integrated pollution index
showed that the pollution level was Cd > Cu > Zn > Pb, and Cd, Cu and Zn belong to heavy pollution level. The residual, Fe
and Mn oxide-bound, and organic-bound species accounted for about 90%, while carbonate-bound and exchangeable species accounted
for about 10%. This study indicates that the soils in the industrial zone were widely and extremely polluted by multi-heavy
metals as a result of long-term industrial activities. 相似文献
116.
通过对108国道和潼江支流魏刘河二侧土壤中重金属元素的富集系数(EF)计算研究,总结了该研究区公路(Ro型)和河流(Rv型)二种EF值典型特征,同时指出该研究区河流为污染源的贡献者,而公路通过改变土壤物理结构,造成污染的程度增大。 相似文献
117.
铬是一种重金属痕量元素,人体通过食物链摄入过量的铬会在人体内富集,随之产生中毒反应。研究Cr(III)的浓度、反应时间、反应温度、pH值等因素对Cr(III)在黄土上吸附特性的影响,结果表明黄土对Cr(III)的吸附非常迅速,并且吸附量非常大,等温吸附模型Freundlich和Dubinin-Radushkevich(D-R)模型都能很好地解释Cr(III)在黄土上的吸附过程。热动力学分析表明,吸附是一个自发的过程,升温可促进吸附作用的进行。随着温度的不断升高,Cr(III)的吸附量逐渐增大。溶液的pH值是影响Cr(III)吸附效果的一个重要因素,当pH>6时,Cr(III)几乎完全被去除。利用X光衍射图谱和红外光谱分析,探讨黄土与Cr(III)的结合机制,黄土中的高岭土、石英等黏土矿物以及有机质成分对吸附过程起重要作用。 相似文献
118.
????????????????????????????????????????????б????????????????????????????????????????????????????????????????????????????????????????仯?????????仯???????????????????????????δ??????????????????????????????????????????仯????????????????????????е?????????????????????????????????????????????????????????????С???????????0.01??????????????????1???????????????????????????????Ч??????? 相似文献
119.
Located in Liaoning Province, one of the traditional heavy industrial areas in China, Dahuofang Reservoir provides drinking water for nearly 30 000 000 citizens, as well as industrial and agricultural water for dozens of several cities and rural areas. The distribution of hazardous heavy metals is described in several types of soil, crops, and in different industrial or mining areas and main sewage irrigation areas. Five possible reasons that may cause the pollution are analyzed and listed. Also we provide some pragmatic suggestions for the remediation of heavy metals in contaminated soils. 相似文献
120.
Sunil K. Jha 《洁净——土壤、空气、水》2012,40(12):1392-1400
The geochemical characteristics and the spatial distribution of the fluoride were studied in the soils of Indo‐Gangetic plains using multivariate analysis. The fluoride (F) distribution in soil profiles and surface soil (0–15 cm) samples were studied. It was found that total fluoride (TF) in the profiles ranged from 248 to 786 mg kg?1 with a mean of 515.1 mg kg?1 whereas CaCl2 extractable soluble fluoride (FCa) was found to be in the range of 1.68 to 99.1 mg F kg?1 soil. On the other hand, in surface soils, the TF and FCa ranged from 118 to 436 mg kg?1 with a mean of 251.2 mg kg?1 and 1.01 to 5.05 mg kg?1 with a mean of 2.12 mg kg?1, respectively, in the study area. The principal component analysis revealed that the natural weathering of fluoride bearing rock and minerals, various ion‐exchange and dissolution processes in the soil, alkalinity, sodium adsorption ratio, calcium (Ca), magnesium (Mg), and clay contents of the soil are responsible for high fluoride occurrence in the area. The fluoride contamination index developed by using these factors could explain more than 76% variance of F contamination due to FCa in soils. The interpolated kriged map of FCa in surface soil indicated a distinct loop of 1.0–2.0, 2.0–3.0, 3.0–4.0, and >4.0 mg kg?1. 相似文献