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采用HCl,HNO3,H2SO4,HAc,NaAc(pH=8.15)和NaAc(pH=3)作为浸取剂,分别对飞灰进行了浸出实验。NaAc(pH=3)浸出效果最好。以NaAc作浸取剂,对不同液固比(L/S)、浸取液浓度、浸出时间和初始pH值实验条件下Pb和cd的浸出效果进行分析,结果表明浸取剂浓度为0.5mol/L、液固化为10、浸出时间为60min和浸取液初始pH值等于3时对飞灰中的Pb和Cd浸出效果最好。 相似文献
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共存离子对地浸废水中铀生物沉淀过程的影响 总被引:1,自引:0,他引:1
采用硫酸盐还原菌生物(还原)沉淀法消除地浸废水中的放射性铀污染,研究了共污染离子Cu(II)、Zn(II)、Fe(III)和SO42-分别对铀生物沉淀过程的影响。序批式实验结果表明,初始Cu(II)浓度低于10mg/L或Zn(II)浓度低于20mg/L时对铀生物沉淀过程影响不大,当Cu(II)浓度超过15mg/L或Zn(II)浓度超过25mg/L时,该过程会因重金属的生物毒性作用受到完全抑制。在含有Fe(III)的氧化环境中,铀生物沉淀过程与Fe(III)还原过程同时进行,但铀沉淀速度相对减慢。初始SO42-浓度低于4000mg/L时对铀生物沉淀过程影响很小,超过5000mg/L时会产生明显的抑制作用,且抑制作用随着SO42-浓度的上升而加强。 相似文献
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Environmentally available concentrations of Fe, Mn, Zn, Cu, Pb, Cr and Ni in soils and sediments from a small suburban catchment, obtained using an acid leach procedure, are compared to the Ontario Ministry of the Environment lowest effect level (LEL) and severe effect levels (SEL) and to Provincial sediment quality guidelines (PSQG's). These data are then compared to the bioavailability, potential bioavailability and non-bioavailability of the same metals, plus oxalate concentration, identified using a selective extraction procedure. This combination of techniques enhanced analytical interpretation with respect to metal mobility and potential metal contamination. Selective extraction highlighted the presence of oxalate as a potential contaminant, especially in poorly drained valley floor deposits (33,633 mg kg(-1) and 26,284 mg kg(-1)) and lakeshore sediments (27,095 mg kg(-1) and 13,729 mg kg(-1)). These levels are considerably in excess of those previously documented in a similar study from Rio de Janeiro, where contamination of urban sediment by sewage is a recognised environmental problem, and could possibly be used both as an indicator of similar contamination and the identification of those areas that warrant further investigation. 相似文献
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选取我国西北地区广泛分布的黄土进行模拟降水淋溶实验,研究了在动态淋溶系统中盐基离子和SiO2、Cl-等黄土主要组份的释放规律及淋出液的pH值变化特点,在此基础上对黄土中各矿物元素的淋溶释放机制进行了探讨。结果表明,黄土中的Na+、Ca2+、Mg2+、Cl-主要通过快速的无机盐溶解过程淋失,而K+、SiO2的淋溶释放则与缓慢的硅酸盐矿物风化有关。粗略的通量计算结果显示,在黄河流域,降水淋溶侵蚀作用每年可从黄土中淋失盐基离子40.7 × 109mol,占黄河溶解态物质入海通量的近20%。 相似文献
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含铬(Ⅵ)污水对地下水、土壤污染的研究 总被引:5,自引:1,他引:5
通过模拟含铬(Ⅵ)污水的土壤淋滤过程,结合受污染区域土壤垂直含铬分布分析,研究了含铬污水渗漏对地下水、土壤的污染。结果表明:含铬污水在亚粘土、亚砂土、砂土中的平均渗透系数分别为6.02×10-6cm/s、3.87×10-4cm/s、5.32×10-4cm/s。含铬污水排放会在土壤中沉积铬,引起土壤污染,并污染地下水。 相似文献
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论生活垃圾处理与污染防治技术 总被引:3,自引:0,他引:3
详细分析了国内外生活垃圾污染途径和处理方法,根据中国生活垃圾的现状和特点,就国内外现有不同处理方式,提出了较为町行的生恬垃圾卫生填埋和污染防治技术。 相似文献
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LIN Min 《环境科学学报(英文版)》2000,(4)
IntroductionThemetalmeltingindustryisoneofthelargerindustriesworld wide ,includingironandsteelfoundriesandmills,aswellasbrassandbronzefoundries (Morgan ,1 977;Gill,1 981 ;Brooks,1 991 ;Collie ,1 984;Swarnkar,1 996 ;Peters,1 992 ;Elgersma,1 992 ) .Duringthemetalmeltingprocess,theele… 相似文献
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Multi-element analysis of road-deposited sediment in an urban drainage basin, Honolulu, Hawaii 总被引:18,自引:0,他引:18
Road-deposited sediment (RDS) and its associated contaminant load play a critical role in degrading receiving water bodies. Few quantitative multi-element RDS studies exist, and there are none from Hawaii. This lack of baseline data combined with concerns with high concentrations of Pb and Cu in fish and enrichment of Cu, Pb and Zn in bed sediments from Manoa Stream, Hawaii, lead to a detailed characterization of RDSs in Manoa basin. Data for a total analysis of 23 elements using inductively coupled plasma atomic-emission spectrometry and instrumental neutron activation analysis and 16 elements using a 0.5 M HCl partial leach are presented for RDSs and background soils. Concentration data, comparisons with environmental guidelines, and concentration enrichment ratios (CERs) all indicate that RDS in Manoa has a significant degree of anthropogenic pollution. The most environmentally important elements were Pb, Sb and Zn. Concentrations of these elements, primarily vehicle contributed, compare favorably with those from other studies of RDS. The high mean concentration of Pb (151 mg/kg) compared to background soils (13 mg/kg) indicates remobilization of Pb previously stored in soils and transported to road surfaces by water erosion processes. The higher Pb CER(Total) in RDSs compared to bed sediments from Manoa Stream suggests a potential link via ubiquitous storm drains and subsequent dilution with less contaminated fluvial sediments. Data from the HCl leach also support Pb and Zn as having significant anthropogenic signals, and Cu having a moderate signal. These data indicate that RDSs in Manoa basin are generally contaminated with certain potentially toxic elements and the legacy of past use of leaded gasoline is still a concern in this urban drainage system. 相似文献
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中国岩溶山区每年都要产生大量的工业固体废弃物,这些工业固体废弃物在堆存过程中,主要由于降水的淋溶作用,引起了二次水污染现象,对地表地下水环境产生了很大影响。在建设项目环境影响评价工作中必须对此加以重视。 相似文献