废弃日用品塑料中多溴联苯醚浸出特征及地下水健康风险

选择典型废弃日用品塑料,对特征处置场景下其PBDEs的浸出特征及健康风险进行了评价.结果表明,日用品塑料在硫酸/硝酸、醋酸和腐殖酸溶液中达到溶出平衡时,∑21PBDEs释放量分别为20.00、63.65、125.60μg·kg-1,均以BDE209为主.进入生活垃圾填埋场的释放量高于堆存和简易填埋过程,在最不利条件下距填埋场下游500 m处地下水中PBDEs最大浓度为39.67μg·L-1,居民饮用地下水产生的非致癌风险指数为2.11×10-1,其中十溴代物(BDE209)的非致癌风险指数为1.85×10-1,均小于美国标准中非致癌的可接受风险水平(1.0),表明废旧日用品塑料可进入生活垃圾填埋场处置.     

Leaching of trace and major elements from coal ash dumps

Coal ash samples taken from an active, currently filled cassette as well as samples taken from passive cassettes of the power plant in Obrenovac (Yugoslavia) were subjected to sequential leaching, comprising of extraction with distilled water, 1 M KC1 and 0.1 M HC1. Concentrations of trace and major elements found in extracts revealed that lead and cadmium are not present in significant concentrations, while other elements show different behavior: practically all absorbed trace elements and most of the major elements are partially leached during transport, while later, on the dump, only a slow release of most of the examined ion‐exchangeable elements occurs.     

废碱锰电池焙烧干粉中Mn2+浸出行为的研究

研究了废碱性锌锰电池焙烧干粉(BakePowderofSpentAlkalineZincManganeseBattery,简称SLR干粉)在硫酸体系中的酸解行为,分析了硫酸浓度、反应温度、催化剂用量和固液比对SLR干粉中Mn2+浸出率的影响,探讨了在硫酸体系中Mn2+的浸出行为。试验数据表明:硫酸浓度和催化剂用量对反应影响较大,同时得出了最佳的酸解反应条件:硫酸浓度10%、反应温度40℃、催化剂用量2%(体积比)、固液比1:10和反应时间2h。在此条件下Mn2+浸出率达87%以上,为进一步回收利用废碱性锌锰电池提供理论依据。     

Leaching characteristics of bisphenol A from epoxy-resin pavement materials

We investigated the leaching characteristics of bisphenol A (BPA) from two kinds of epoxy-resin pavement materials, one containing epoxy resins (EPs) and the other containing epoxy-acrylate resins (EPAs). Both samples contained residual BPA monomer, at levels of 9.0?µg?g^?1 for the EP resin sample and 4.4?µg?g^?1 for the EPA resin sample. These amounts were larger than amounts previously measured for polycarbonate samples. The amount of BPA leached from the samples increased with temperature. The leaching of BPA from EP was more strongly affected by temperature than the leaching from EPA. The pH also affected the amount of leached BPA. The maximum leached amount was observed under alkaline conditions (pH 10.8) for both sample types. The amounts of BPA that might leach from pavement materials during 1?h of heavy rain were estimated to be 0.9?µg?m^?2 for EP and 3.5?µg?m^?2 for EPA. Our results indicate that EPs disposed of in waste landfills without any treatment may be a source of BPA in leachate at landfill sites.     

Leaching of elements from flue dust produced in copper scrap smelting process

To understand the features and leaching characteristics of copper (Cu) scrap smelting dust and its potential risk to environment and humans, three types of smelting dust were sampled and investigated. The dust samples were collected from the dust captured by cyclone collector, panel cooler, and bag house in a typical Cu scrap smelting process of a factory in Guangxi of China. Zinc (Zn), Cu and lead (Pb) were the main elements of the samples of cyclone collector dust (CCD), panel cooler dust (PCD), and bag house dust (BHD). There were less arsenic (As), Pb and Cu in CCD than PCD and BHD, and PCD contained more manganese (Mn), nickel (Ni), and iron (Fe) than BHD. The particle shapes of BHD appeared more regular than CCD and PCD, and energy dispersive X-ray spectroscopy analysis illustrated the compositions of selected surface areas of three samples. The size of particles ranged from 0.011 to 33.11 μm in CCD, from less than 1 μm to several mm in PCD, and from 0.832 to 363.078 μm in BHD. The main elements in leachate were Zn and Mn from CCD, Zn, cadmium (Cd) and Pb from PCD, Zn, Mn and Cd from BHD. The leaching toxicity risk of Cd, Mn, and Zn of PCD and BHD was higher than CCD.     

菜田土壤氮素淋失及其调控措施的研究进展

从菜田中硝态氮的动态变化、土壤氮素的矿化、硝态氮对地下水的影响等几方面概述了近年来国内外的研究进展，介绍了渗漏测定计法、土壤溶液提取器和15N同位素示踪技术等3种测定土壤氮素淋失的研究方法其应用前景；论述了影响菜田土壤氮素淋失的主要因素和降低菜田土壤氮素淋失的丰要调控措施；提出了今后菜田土壤氮素淋失应加强的研究方向。     

江苏省武进市高产水稻田氮素渗漏损失研究

小区试验与农户调查研究结果表明 ,2 87kg/hm2施氮量宜作为武进市高产水稻的适宜施氮量 ,氮肥的过多施用不仅导致秸秆对氮素的奢侈吸收 ,也加重氮肥对渗漏水的污染。进一步降低水稻田施氮水平 ,又保持高产的水稻生产技术尚待开发。     

青霉素钠在土壤中的吸附和淋溶特性

分别采用振荡平衡法和土柱淋溶法分析了青霉素钠在不同土壤中的吸附和淋溶特性及其影响因素。结果表明,25℃以下,3种供试土壤对青霉素钠的吸附特性能用Freundlic模型进行较好的拟合,江西红壤、太湖水稻土和东北黑土的吸附常数KF分别为30.73、39.26和64.58 m L·g-1。偏最小二乘法(PLS)分析表明土壤黏粒含量和有机质含量是影响土壤吸附青霉素钠的主要因素。供试土壤对青霉素钠的吸附自由能变化值均40 k J·mol-1,该吸附过程主要属于物理吸附,吸附能力由大到小依次为东北黑土、太湖水稻土和江西红壤。土柱淋溶试验结果显示,土壤有机质含量和黏粒含量亦是影响淋溶过程的主要因素,青霉素钠在土壤剖面中的迁移能力较弱,3种土壤淋溶性能由大到小依次为江西红壤、太湖水稻土和东北黑土。     

丁噻隆在土壤中的吸附和淋溶特性

分别利用振荡平衡法和土柱淋溶法研究了丁噻隆在不同土壤中的吸附和淋溶特性及其影响因素。结果表明,丁噻隆在5种供试土壤中的吸附特性能较好地用线性模型拟合,吸附能力顺序为:东北黑土>太湖水稻土>江西红壤>南京黄棕壤>陕西潮土,吸附常数Kd为0.19~2.87 mL.g-1,吸附性能较差。丁噻隆在3种典型土壤中的淋溶试验表明其具有较强的淋溶性,淋溶速率为:江西红壤>太湖水稻土>东北黑土。影响丁噻隆吸附和淋溶的主要因素是土壤有机质含量。     

人工甜味剂在不同类型土壤中的淋溶行为研究

人工甜味剂(artificial sweeteners)是一类人工合成或半合成的蔗糖替代品,广泛应用于食品、药物、个人护理品和饲料中,但是大多数人工甜味剂在人和动物体内几乎不被代谢而随尿液和粪便直接进入环境。在天津污水河沿线及甜味剂厂附近不同深度土层中检测到安赛蜜、糖精、甜蜜素和三氯蔗糖。为探讨人工甜味剂在土壤中的移动性及其对地下水污染的风险,应用土柱淋溶实验研究了安赛蜜和三氯蔗糖在2种土壤中的淋溶行为,并观测了人工甜味剂淋溶对土柱淋出液的溶解性有机质(DOM)、pH以及电导率(EC)的影响。结果表明安赛蜜和三氯蔗糖在2种土壤中表现出较强的移动性,超过87%的甜味剂均被淋出,只有不到13%的甜味剂被土壤截留或损失,因此对地下水具有较大的风险。安赛蜜和三氯蔗糖能够促进土壤溶解性有机质的溶出,但对淋出液的pH和电导率无显著影响。     

稻田土壤磷淋失潜力与磷积累的关系

了解稻田土壤磷积累对排水和渗漏液中磷浓度的影响,可为稻田磷素淋失预测提供依据.采用室内模拟方法,研究稻田土壤Olsen-P水平与土壤溶液中磷质量浓度之间的关系.结果表明,土壤溶液中磷质量浓度随土壤Olsen-P水平增加而增加,其中,黏土、壤黏土和壤土的Olsen-P超过临界值(分别为84、65和53 mg·kg-1)后,土壤溶液中磷质量浓度显著增加.土壤Olsen-P水平较低时,黏土、壤黏土和壤土的土壤磷素积累与排水和渗漏液中磷质量浓度之间的关系较为相近,这3类土壤溶液中磷质量浓度与土壤Olsen-P水平存在线性相关关系.而砂土溶液中无明显临界值,砂土溶液中磷质量浓度与土壤Olsen-P水平间也存在线性相关关系.相同Olsen-P水平时,砂质土壤磷淋失潜力明显高于其他土壤.     

镍钴采选行业废石和尾矿中重金属淋溶释放规律研究

镍钴采选废石和尾矿中重金属的溶出释放规律对矿区的重金属污染防治具有重要意义。但目前,国内还没有对镍钴行业采选产生的尾矿和废石中重金属的溶出规律开展研究。本文以镍钴采选企业的尾矿和废石作为样本,开展了毒性浸出实验。研究了不同pH值、离子强度、温度等实验条件对重金属溶出的影响,探讨了镍钴采选过程中所产生的尾矿和废石中重金属的溶出特性和释放规律。实验结果表明,尾矿样品中Ni的浸出浓度为42.28 mg·L^-1,是最大允许排放浓度的8.86倍,为具有浸出毒性特征的危险废物;废石样品中重金属Ni和Cu的溶出浓度分别为4.72 mg·L^-1和26.2 mg·L^-1,超过最大允许排放浓度,属于第Ⅱ类一般工业固体废物。pH对样品中Ni、Cr、Pb、Co和As的溶出量影响较大,其中尾矿中Ni和Cu在pH较低的条件下,可达到44.28 mg·L^-1和53 mg·L^-1,远高于最大允许排放浓度,而Hg、Cd和Cu的溶出量随pH值的变化不大。除As以外,样品中大多数重金属的溶出质量浓度在酸性条件下比在中性条件下高,这表明在酸性环境条件下,这些重金属对周围生态环境的潜在风险更大。离子强度的变化对Cd和Co的溶出量的变化并不明显,而当离子强度变化时,Ni、Cr、Pb、Hg、Cu和As的溶出量可能达到最大,使周围环境的潜在生态风险增大。当温度达到35~40℃时,部分重金属如Co、Pb、Cd 等,溶出量将达到最大;当温度低于25℃时,除 Ni 以外,大部分重金属溶出量很低。而温度变化对重金属Cu、As、Cr和Hg的溶出量的影响不明显,波动范围较小,对周围生态环境产生的潜在生态风险较小。     

热带亚热带多雨湿润区旱地土壤氮肥淋溶损失模拟研究

用土柱研究旱地土壤60cm土体夏季的氮肥淋溶损失,结果表明,在土壤施尿素后35d内淋水350mm,在不产生泾流的条件下,淋失率平均为25．5％。还探讨了氮肥淋溶过程中的氮形态变化,以及施氮量和土层深度对氮肥淋浴损失的影响。     

国外关于稳定化/固化的有毒有害污染物的渗漏实验方法的研究进展

以水泥为基质的稳定化 /固化 (Stabilization/solidification)的方法在国外广泛用于无机、有机、有毒有害污染物的最终处置 ,已经有数十年的历史。论文较全面地介绍了拟合被这种稳定化 /固化过程处理过的污染物在自然界条件下短期和长期的污染物泄漏过程 ,即所谓短期、长期的渗漏行为的实验方法和数学模型 ,并总结了现有几种用来模拟短期或长期渗漏行为的渗漏实验方法和适用于这些实验方法的数学预测模型的应用条件。     

经过水泥固化的重金属废物的穿透渗漏实验

采用穿透渗漏实验方法研究了经水泥固化的重金属废物的长期渗漏行为。用由Ｐｂ＾２＋、Ｚｎ＾２＋、Ｃｕ＾２＋、Ｎｉ＾２＋和Ｃｒ＾６＋５种重金属组成的合成废物样品进行２组实验。实验研究了渗漏实验液流速、ＰＨ的变化和金属渗漏能力对固体废物长期渗漏行为的影响。     

Leaching Characteristics of Lead and Cadmium From Waste-To-Energy Residues in Sea Water

Laboratory studies were conducted to determine leaching characteristics of waste-to-energy (WTE) residues in sea water to provide initial evaluation on the potential impact of WTE residues on the marine environment. Both loose and stabilized WTE residues were investigated for the leachability of lead (Pb) and cadmium (Cd) in sea water. Results of the study showed that loose WTE fly ash was very reactive in sea water; release of Pb and Cd occurred immediately (<0.5 hr) after the ash came in contact with sea water. Stabilization (treated with Portland cement and other additives), however, significantly reduced leaching of Cd and Pb. While ocean disposal of untreated WTE residues would not be advisable, utilization of stabilized WTE residues for beneficial uses should be investigated.     

澳门城市垃圾焚烧底灰的重金属淋溶及其遗传毒性评价

应用美国国家环境保护局推荐的毒性特性溶出程序(toxicitycharacteristicleachingprocedure,TCLP),以及ICP-MS和ICP-AES技术研究了澳门城市垃圾焚烧底灰中重金属的淋溶,并结合蚕豆根尖微核试验评价了其潜在的生态与健康风险.结果显示,该底灰淋溶出来的重金属元素:铝(Al)、锰(Mn)、钴(Co)和汞(Hg)的浓度低于0.01mg·L-1,铁(Fe)、铜(Cu)和钼(Mo)的浓度低于0.1mg·L-1,而铬(Cr)、锌(Zn)、硒(Se)、锶(Sr)、钡(Ba)和铯(Cs)的浓度在0.11mg·L-1￣2.19mg·L-1之间.需要注意的是淋溶液中铅(Pb)的浓度异常高,最高可达19.06mg·L-1,超过了美国相关标准的上限(5mg·L-1);对比不同条件下底灰中重金属的淋溶情况,表明溶解作用和淋溶液的pH值是影响其淋溶的2个重要因素.蚕豆根尖微核试验显示各淋溶液处理组根尖细胞微核率明显升高,与阴性对照组相比具有显著性差异(p<0.05),表明各淋溶液具有遗传毒性;随着淋溶液中重金属浓度的增加,蚕豆根尖细胞所表现出来的毒性效应增强,表明重金属是淋溶液具有遗传毒性的重要原因.     

Leaching toxicity characteristics of municipal solid waste incineration bottom ash

The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical properties and leaching behavior of MSWIBA were studied, and ecotoxicological testing using a luminescent bacterium bioassay was performed to assess the ecological pollution risks associated with its leached constituents. The MSWIBA was leached by two types of leachants, H₂SO₄/HNO₃ and HAc solution, at different liquid to solid ratios and contact times. The concentrations of heavy metals and anions in the leachates were analyzed. Multivariate statistical analyses, including principle component analysis, Pearson's correlation analysis and hierarchical cluster analysis, were used to evaluate the contributions of the constituents to the toxicity (EC₅₀) of the MSWIBA leachate. The statistical analyses of the ecotoxicological results showed that the Ba, Cr, Cu, Pb, F⁻ and total organic carbon (TOC) concentrations were closely correlated with the EC₅₀ value, and these substances were the main contributors to the ecotoxicity of the MSWIBA leachate. In addition, the cluster of these variables indicated similar leaching behaviors. Overall, the research demonstrated that the ecotoxicological risks resulting from MSWIBA leaching could be assessed before its utilization, which provides crucial information for the adaptation of MSWIBA as alternative materials.