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污染底泥的处理处置是河道治理的重要内容,然而传统填埋处置方式不利于生态保护和可持续发展。文章详细总结了珠三角地区河涌底泥的营养成分、矿物组分、污染情况等方面的研究成果,分析了各因素对底泥处理处置方案的影响,研究发现底泥污染程度及污染物毒性限制了其作为土地利用的途径;对污染程度较重的底泥,需采用严格的修复技术措施处理后,方能进行工程化应用;矿物组分决定了底泥是否适用于建材生产。结合实际案例,分析了常见底泥处理处置技术的优缺点及其在珠三角区域的适用性与市场前景,并对珠三角底泥资源化应用途径和方式提出了建议。 相似文献
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河湖环保疏浚处理工程会产生大量的疏浚底泥,底泥中含有氮磷营养盐、重金属、有机物等多种环境污染物,若不予以合理的处理处置,将对生态环境造成严重的二次污染。系统介绍了河湖疏浚底泥的化学组成特征,综述了河湖疏浚底泥调理、脱水、固化、稳定化、异位修复等常规处理方法的优缺点和适用性,总结了现有的河湖疏浚底泥资源化利用途径,并针对污染河湖疏浚底泥处理处置技术研究现状及存在的问题,从生态风险评估、新型处理技术发展和绿色资源化利用产业、质量基准和技术规范构建等方面展望了河湖疏浚底泥处理的后续重点研究方向。 相似文献
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污染底泥是水体最主要的内源,存在污染物二次释放的风险,而环保疏浚可以有效地清除污染底泥、降低内源污染负荷及其释放风险,因此近年来该技术在水环境治理中得到广泛的应用.环保疏浚的主要目的是有效清除河流、湖泊(水库)水体污染底泥中累积的污染物,并对浚后污泥进行安全处理处置,为污染河流、湖泊(水库)水质改善与生态修复发挥工程作用.作为湖泊、河流水污染综合治理技术体系的重要组成部分,环保疏浚是生态环境工程技术之一,也是湖泊河流水污染治理的重要手段;但底泥疏浚同时也存在疏浚效果不理想、可能造成原位扰动与异地污染、改变水生态系统的结构与功能等生态风险.研究显示,未来环保疏浚的主要发展方向应包括:① 基于调查评估基础上的污染底泥分区、分类环保疏浚及处理处置研究;② 污染底泥环保疏浚与区域生态修复一体化设计研究;③ 污染底泥环保疏浚-浚后干化-处理处置-资源化集成技术研究;④ 污染底泥环保疏浚、处理和资源化全过程监管评估技术研究. 相似文献
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浑河中游制药、石化工业水污染是最大的工业污染,废水具有有毒有害、难降解等特点;浑河中游支流河水污染严重。为了控制水污染,改善水环境,国家水体污染控制与治理科技重大专项课题开展了区域水污染控制与水环境修复技术研发和创新。针对黄连素废水和磷霉素钠废水,研发了臭氧氧化、脉冲电絮凝、铁碳微电解等物化处理工艺以及物化-生化耦合处理工艺,实现了制药废水的有效处理;针对石化腈纶废水,研发了多格室脱氮反应器、膜生物反应器-臭氧氧化-曝气生物滤池全流程处理工艺,实现了腈纶废水氨氮脱除和达标处理;针对浑河中游支流河污染问题,研发了塘和湿地组合生态净化技术、污染底泥的安全处理处置与资源化利用技术。 相似文献
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建立了一套模拟湖泊小试装置,分别采用含黏土的沙子、清洁黄土和土工布3种材料覆盖湖泊污染底泥,抑制底泥中的氮释放。试验控制在恒温25℃厌氧条件下进行,经过75d静置试验,结果表明:含黏土的沙子和清洁黄土均能有效抑制污染底泥的氮释放,而单独使用土工布的效果不佳;覆盖材料的覆盖厚度越厚,抑制污染底泥氮释放的效果越好;覆盖厚度为5cm、15cm和30cm的沙子对污染底泥氮释放的抑制率分别为74.9%、94.0%和96.8%,覆盖厚度为5cm、15cm和30cm的黄土对污染底泥氮释放的抑制率分别为77.2%、95.5%和98.8%,可见黄土的效果更优;从工程成本考虑,采用15cm覆盖厚度即可。 相似文献
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延河沉积物的石油污染调查与分析 总被引:10,自引:1,他引:10
对延河干流和两条支流受石油污染河段的沉积物的取样分析结果表明 ,研究河段内的沉积物都不同程度的受到了石油污染。干流河段沉积物的石油污染负荷一般为 40~ 80mg/kg ,上游河段和污染支流汇入段负荷较高 ,平均为390mg/kg,最高可达 784mg/kg ;支流上的坪桥川和杏子河河段沉积物污染负荷为 6 0~ 2 5 0mg/kg。干流中下游及杏子河支流河段的污染沉积物主要来源于雨期流域表层污染土壤径流入河后的沿程沉积 ,而非雨期岸边油井的直接排污则是造成干流上游和坪桥川支流沉积物石油污染的主要原因 相似文献
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Mercury in sediments and vegetation in a moderately contaminated salt marsh
(Tagus Estuary, Portugal) 总被引:1,自引:1,他引:0
Jo?ao Can′ario Carlos Vale Laurier Poissant Marta Nogueir Martin Pilote Vasco Branco 《环境科学学报(英文版)》2010,22(8):1151-1157
Depth variations of total mercury (Hg) and methylmercury (MeHg) concentrations were studied in cores from non-colonized
sediments, sediments colonized by Halimione portulacoides, Sarcocornia fruticosa and Spartina maritima and belowground biomass,
in a moderately contaminated salt marsh (Tagus Estuary, Portugal). Concentrations in belowground biomass exceeded up to 3 (Hg) and
15 (MeHg) times the levels in sediments, and up to 198 (Hg) and 308 (MeHg) times those found in aboveground parts. Methylmercury
in colonized sediments reached 3% of the total Hg, 50 times above the maximum values found in non-colonized sediments. The absence
of correlations between total Hg concentrations in sediments and the corresponding MeHg levels suggested that methylation was only
dependent on the environmental and microbiological factors. The analysis of belowground biomass at high-depth resolution (2 cm)
provided evidence that Hg and MeHg were actively absorbed from sediments, with higher enrichment factors at layers where higher
microbial activity was probably occurring. The results obtained in this study indicated that the biotransformation of Hg to the toxic
MeHg could increase the toxicity of plant-colonized sediments. 相似文献
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污染底泥释放控制技术的研究进展 总被引:25,自引:0,他引:25
从受污染底泥的危害入手 ,提倡在有效控制外源的同时 ,积极对受污染底泥的释放进行控制。根据控制方法原理的不同将污染底泥释放控制技术分为物理控制技术及生物控制技术 ,并综述了上述控制技术的研究及应用概况 ,并对其利弊作出评价 .最后 ,分析了受污染底泥释放控制技术的发展方向。 相似文献
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根据底泥原地处理技术原理,基于有机粘土矿物的环保性能,以菲为目标污染物,开展向底泥中加入表面活性剂(十六烷基三甲基溴化铵,HDTMA-Br)和有机粘土矿物(十六烷基三甲基溴化铵改性膨润土,HDTMA改性土)后对其吸附菲的性能影响研究。结果表明,底泥对菲的吸附作用主要表现为表面物理吸附特征,吸附等温线符合Freundlich方程;底泥中加入HDTMA+或HDTMA改性粘土后菲在两相间的表观分配系数增大,吸附分别为表面作用和分配作用;菲在底泥上的解吸曲线呈较好线性,吸附不存在滞后效应,而在加入表面活性剂和有机粘土矿物的底泥上线性变差,对菲的吸附出现不可逆吸附现象,吸附变得稳定;在污染物浓度很低的情况下,pH、盐度和温度的改变对吸附量的影响不大。 相似文献
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云南金顶铅锌矿区水系沉积物中镉的地球化学分布及其环境质量 总被引:7,自引:0,他引:7
云南金顶超大型矿区长期矿业活动对矿区水系沉积物造成了严重的镉污染.北大沟河流沉积物中Cd含量低于南大沟;沘江不同河段沉积物中Cd含量差异较大,矿区上游沘江段沉积物中镉含量较低(平均值低于10 mg·kg-1),池江下游污染段沉积物中Cd含量显著增加(平均值为266 mg·kg-1).沉积物中Cd污染系数最大(R为21.9-45.2),高于zn(R为4.9~9.7)和Pb(R为2.7~4.6).地累积指数法分析结果显示,矿区水系沉积物污染元素按污染强度分为:Cd>Zn>Pb.南大沟和沘江矿区下游段部分沉积物达到严重污染,北大沟大部分河段沉积物为重污染,少数河段沉积物为偏重污染或中度污染,沘江金顶段上游河段沉积物为轻度污染或无污染.从南大沟汇入沘江口段到下游温庄村段沉积物中重金属污染有增强的趋势. 相似文献
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Assessing the capacity of biochar to stabilize copper and lead in contaminated sediments using chemical and extraction methods 总被引:1,自引:0,他引:1
Mingming Wang Liangsuo Ren Dayang Wang Zuansi Cai Xuefeng Xi Aizhong Ding 《环境科学学报(英文版)》2019,31(5):91-99
Because of its high adsorption capacity, biochar has been used to stabilize metals when remediating contaminated soils; to date, however, it has seldom been used to remediate contaminated sediment. A biochar was used as a stabilization agent to remediate Cu- and Pb-contaminated sediments, collected from three locations in or close to Beijing. The sediments were mixed with a palm sawdust gasified biochar at a range of weight ratios (2.5%, 5%, and 10%) and incubated for 10, 30, or 60?days. The performance of the different treatments and the heavy metal fractions in the sediments were assessed using four extraction methods, including diffusive gradients in thin films, the porewater concentration, a sequential extraction, and the toxicity characteristic leaching procedure. The results showed that biochar could enhance the stability of heavy metals in contaminated sediments. The degree of stability increased as both the dose of biochar and the incubation time increased. The sediment pH and the morphology of the metal crystals adsorbed onto the biochar changed as the contact time increased. Our results showed that adsorption, metal crystallization, and the pH were the main controls on the stabilization of metals in contaminated sediment by biochar. 相似文献
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Pengjun Xu Bu Tao Zhiqiang Ye Hu Zhao Yue Ren Ting Zhang Yeru Huang Jiping Chen 《环境科学学报(英文版)》2016,28(10):102-111
The concentrations of 16 priority polycyclic aromatic hydrocarbons(PAHs) were measured in 23 farmland soil samples and 10 riverine sediment samples from Guiyu, China, and the carcinogenic risks associated with PAHs in the samples were evaluated. Guiyu is the largest electronic waste(EW) dismantling area globally, and has been well known for the primitive and crude manner in which EWs are disposed, such as by open burning and roasting. The total PAH concentrations were 56–567 ng/g in the soils and 181–3034 ng/g in the sediments.The Shanglian and Huamei districts were found to be more contaminated with PAHs than the north of Guiyu. The soils were relatively weakly contaminated but the sediments were more contaminated, and sediments in some river sections might cause carcinogenic risks to the groundwater system. The PAHs in the soils were derived from combustion sources,but the PAHs in the sediments were derived from both combustion and petroleum sources. 相似文献