330 MW燃煤机组异相凝并对重金属排放控制的实验研究

湖北某电厂1号机组容量为330 MW，配备双室四电场静电除尘器，为了考察异相凝并技术对细颗粒物以及重金属脱除效率的影响，对1号机组除尘器前后，脱硫塔后进行颗粒物与重金属采样测试。结果表明，在烟道中喷射凝并吸附剂后，ESP入口颗粒态重金属占比增加，其中，Se元素在PM_2.5和PM₁₀上增加尤为明显，而气态的重金属含量有所降低，表明凝并吸附剂增强了颗粒态重金属的凝并效果，小颗粒态与气态重金属通过异相凝并过程转移至大颗粒态。喷入凝并吸附剂后，石膏中重金属含量显著降低，说明能够进入脱硫石膏的重金属含量减少，异相凝并提升了ESP对重金属的脱除作用；在尾部烟道末端烟囱排放口采样点，重金属含量相较于未喷入凝并吸附剂的工况，有着明显的降低，表明了经过异相凝并之后，排放至大气中的重金属显著减少，异相凝并对于重金属的控制起到关键作用。     

一氧化碳高效吸附剂CuCl／分子筛

利用自发单层分散原理，将ＣｕＣｌ分散在载体表面制备高效的ＣＯ吸附剂，将ＣｕＣｌ与γ－Ａｌ２Ｏ３，４Ａ，１３Ｘ，ＮａＹ，ＣｕＹ分子筛等高比表在载体混合，在３５０℃焙烧数小时，ＸＲＤ和ＥＸＡＦＳ研究证明ＣｕＣｌ可在载体表面达到原子水平的分散由于Ｃｕ＾＋可与ＣＯ生成配位键。由此可制得对ＣＯ有高吸附容量和选择性的吸附剂，其中ＣｕＣｌ／ＮａＹ和ＣｕＣｌ／Ｃｕ＾＋Ｙ吸附剂的吸附容量在２０℃，ＣＯ分压为６０ｋＰ     

水合氧化铁／石英砂吸附剂的制备及性质

用反复沉淀法和加热蒸发法制备了水合氧化铁／石英砂水处理吸附剂，用电子显微镜观察了它们的表面形态，测定了氧化铁在表面上的附着能力，研究了该吸附剂对重金属离子的吸附和脱附性质．结果表明，加热蒸发法所得样品表面形态复杂；在酸性溶液和机械振荡条件下表面氧化铁有良好附着能力；对Ｃｄ２＋和Ｃｒ３＋有较强的吸附性质．     

新型络合吸附剂的研究（V）铜离子模板高分子三乙烯四胺型络合…

采用缩聚反应，一步法合成了三乙烯四胺（ＴＥＴＡ）型的非模板和以Ｃｕ（Ⅱ）离了为中心模板离子的高分子铜模板络合吸附剂。研究了类吸附剂在静态条件下对重金属离子Ｃｕ＾２＋，Ｎｉ＾２＋，Ｃｏ＾２＋，Ｚｎ＾２＋和动态条件下对Ｃｕ＾２＋，Ｎｉ＾２＋的吸附选择性。结果表明，铜模板吸附剂比非模板吸附剂对重金属离子的吸附选择性显著提高。     

多胺类螯合吸附剂对重金属离子吸附分离的研究进展?

综述了多胺类螯合吸附剂制备方法及其对微污染环境、复杂混合环境、高盐环境中重金属离子的特性吸附行为,重点总结了多胺类螯合吸附剂对重金属离子的吸附结合方式、高效分离机制及盐存在下的增强吸附机制,并进一步展望多胺类螯合吸附剂的应用前景、创新设计思路以及理论探索的研究方向,为拓宽多胺类螯合吸附剂在重金属离子无害化处理和资源化回收方面的应用范围,提供了理论和技术指导。     

H2S、SO2的吸附(干法)脱除研究进展

对近十年国内外Ｈ２Ｓ、ＳＯ２吸附脱除的研究进展进行了述评。首先指出了燃料是硫的主要来源;阐明了Ｈ２Ｓ、ＳＯ２脱除的化学基础;着重分析了高温煤气中Ｈ２Ｓ脱除的吸附剂和财生烟道气中ＳＯ２与ＮＯｘ的同时脱除吸附剂的研究情况;最后指出了影响吸附剂选择的因素。     

新型络合吸附剂的研究（Ⅴ）铜离子模板高分子三乙烯四胺型络合吸附剂的合成和特性

采用缩聚反应，一步法合成了三乙烯四胺（ＴＥＴＡ）型的非模板和以Ｃｕ（Ⅱ）离子为中心模板离子的高分子铜模板络合吸附剂。研究了这类吸附剂在静态条件下对重金属离子Ｃｕ２＋、Ｎｉ２＋、Ｃｏ２＋、Ｚｎ２＋和动态条件下对Ｃｕ２＋、Ｎｉ２＋的吸附选择性。结果表明，钢模板吸附剂比非模板吸附剂对重金属离子的吸附选择性显著提高。     

MnO2的离子交换行为及其离子筛法提取锂

锂在受控核聚变反应中的应用以及高能锂电池的出现，显示了其在解决能源问题的重要意义．但当前查明的锂矿石贮量不大，近年来，人们已开展有关从海水中提取锂的研究．在电解质溶液中ＭｎＯ２表面具有离子交换特性［１］，以ＭｎＯ２和ＬｉＯＨ制得的离子筛型吸附剂，对海...     

K2CO3活化煤矸石制备活性炭吸附剂

用Ｋ２ＣＯ３化学活化煤矸石制备适用于废水处理的活性炭吸附剂．考察了活化条件对产物的比表面、孔体积及灰分的影响．增加了前处理和后处理步骤以改善产物的性能．最佳条件下获得的活性炭吸附剂ＢＥＴ比表面达１２３６ｍ２／ｇ，孔体积０．６７９ｃｍ３／ｇ．所制得的吸附剂表面是疏水性的，对水溶液中的酚类污染物有良好的吸附性能．     

壳聚糖吸附剂的制备及其性能

本文以壳聚糖为主要原料，分别经过悬浮交联和复合制备得到壳聚糖（Ｃｈｉｔｏｓａｎ）树脂吸附剂（简称ＣＳ吸附剂）和壳聚糖—活性炭（Ｃｈｉｔｏｓａｎ－Ａｃｔｉｖｅｃａｒｂｏｎ）复合吸附剂（简称ＣＳ—ＡＣ吸附剂）。研究影响制备吸附剂的诸因素；测定两种吸附剂的性能；探讨两种吸附剂对印染废水的脱色和对有毒金属离子的去除。研究结果表明：本研究条件下制得的ＣＳ和ＣＳ—ＡＣ吸附剂比表面积分别为８２．９Ｍ２／ｇ和９３７．３Ｍ２／ｇ；对亚甲基蓝溶液（５００ｍｇ／Ｌ）的静态吸附量为１４１．２ｍｇ／ｇ吸附剂和８３５．１ｍｇ／ｇ吸附剂；ＣＳ吸附剂对印染废水的动态脱色量为１２６．９ｍｇ／ｇ吸附剂；两种吸附剂对有毒重金属Ｐｂ（２＋）的去除率均达９０％以上，而且耐酸、碱性能较好，均为优良的颗粒状吸附剂。     

Elemental characterization of coal ash and its leachates using sequential extraction techniques

Over 50 million tons of coal ash are produced annually in North America. Technological improvements in air pollution control have decreased stack emissions but have also increased contaminant concentrations in the ash of coal-fired boiler applications. The leaching of heavy metals and other elements during regulatory tests may cause coal ash ro be classified as hazardous waste, complicating land disposal. The hazardous nature of coal ash remains unclear because current toxicity tests fail to effectively characterize the elemental distribution and chemical solubility of trace metals in the landfill environment. Leaching characteristics of ash samples can be investigated with various laboratory extraction procedures in association with multi-elemental analytical techniques (e.g., neutron activation analysis and inductively coupled plasma-atomic emission spectroscopy). Such methods provide more thorough analyses of coal ash leaching dynamics than the regulatory assessments can demonstrate. Regulatory elements including Ag, As, Ba, Cd, Cr, Hg, Pb, and Se were shown to remain in largely insoluble forms while elements such as B and S leached at higher levels. Experimental results may assist operators of coal-fired boiler industries in selecting coal types and disposal options to curtail the leaching of potentially toxic inorganic contaminants.     

某冶炼厂周边土壤重金属污染评价分析及源解析研究

有色金属矿产资源采选冶活动造成的土壤重金属污染已成为严重的环境问题。采用电感耦合等离子体质谱法和光谱法测定某冶炼厂周边不同区域内土壤中重金属Cu、Pb、Zn、As、Ni、Cr、Cd、Hg元素含量,采用Kriging空间插值方法对重金属空间分布特征进行分析,采用内梅罗指数法对其污染状况进行评价,采用多元统计分析对重金属元素的污染源进行分析。结果表明,研究区土壤采样点80%处于污染状态,且以重度污染为主,污染比较严重的区域受风向影响在冶炼厂的西部和南部方向,污染严重的重金属元素为Cu、Pb、Cd、Zn和As,土壤中各重金属元素的污染源除来自于冶炼厂外,Zn-Cd-PbCu-As、Ni-Cr、Hg分别还受到机动车辆排放、自然因素、燃煤及农药使用的影响。     

固体添加剂对垃圾掺烧污泥焚烧飞灰高温过程中重金属挥发特性的影响

在研究垃圾与污泥掺烧后焚烧飞灰中重金属浸出特征的基础上,重点研究了飞灰在1 000 ℃条件下高温处置过程中重金属(Cu、Zn 、Pb、Cd)随不同停留时间的挥发特性及添加剂(CaO、Al₂O₃、SiO₂、高岭土、粉煤灰)对重金属转化与挥发特性的影响。研究结果表明,飞灰中重金属Zn、Pb、Mn含量较高,Ni的含量较低,而毒性较大的Cd达到29.4 mg/kg。浸出液中七种金属都满足危险废物鉴别标准(GB5085.3-1996),并且重金属的浸出浓度受浸取时间及浸取液pH值影响较大。在同样的高温处置条件下,焚烧飞灰中不同重金属的挥发特性有较大的差别。其中,Pb表现出易挥发的特性,其挥发率超过80%,而Cu挥发性较小,其挥发率小于30%。综合来看,飞灰中重金属的挥发性大小依次为Pb>Cd>Zn>Cu。飞灰中添加Al₂O₃和高岭土可以抑制Cd的挥发,添加Al₂O₃后Pb的挥发率有所减少,添加SiO₂、CaO、高岭土、粉煤灰均使Zn的挥发率降低,而对Cu的挥发率没有抑制作用,这与飞灰中高Cl含量及各痕量元素化合物对固体添加剂活性位选择性的竞争吸附有关。     

Feasibility study on reducing lead and cadmium absorption by spinach (Spinacia oleracea L.) in a contaminated soil using nanoporous activated carbon

Activated carbons (AC) have been long recognized as prominent absorbents in industries and feature numerous applications in preventing or absorbing the harmful gases and liquids and could be employed for filtration and remediation or even reutilization of chemicals. In order to investigate the capacity of AC in reducing the absorption of heavy metals (HM) including lead (Pb) and cadmium (Cd) and dual complex (Pb?×?Cd) by spinach, a factorial experiment in a completely randomized design with three replications on a pot trial was conducted. Three factors including five levels of AC 0, 5000, 10000, 15000, 20000?mg/kg soil, one concentration level of Pb 4,000?mg/kg soil and one concentration level of cadmium Cd 8?mg/kg soil were tested. The index of heavy metal concentration was calculated in leaf, stem and root and their corresponding dry weights. Results illustrated that in contaminated soils, plants with AC exhibited a superior reduction of absorption of HM vis-à-vis the plants without AC. The foremost result regarding the impact of AC on reducing the concentration of Pb and Cd was observed in 20,000 level of AC. This reveals that AC declined the soil contamination and lessened the accumulation of HM into the shoots and roots. Results suggest that the application of AC may be an eligible solution for decreasing the translocation of HM into the plants.     

城市生活垃圾焚烧飞灰重金属的浸出特性

对用流化床焚烧炉混烧垃圾和煤的布袋飞灰进行了重金属的TCLP(Toxicity Characteristic Leaching Procedure)浸出特性实验，探讨了液固比、初始pH值及浸出时间对飞灰中重金属Pb、Cr、Cd、Ni、Cu、Zn的浸出影响。结果表明，重金属的浸出量都随着液固比的增加而增加，其中Cr、Cu一般呈上升趋势，Cd、Ni、Zn在液固比大于20时曲线变化较平缓，Pb的浸出规律比较特殊，有一个明显的波峰和波谷。重金属在浸取液的pH≤2.90时的浸出浓度远远大于pH≥4.03时的浸出浓度。Pb、Cr、Zn随着浸出时间的增加，浸出浓度下降，而Cd、Ni上升，Cu是先上升后下降。在液固比、初始pH值及浸出时间这三个影响因素中，pH值对重金属的浸出影响较大，重金属在酸性环境下较易浸出。     

用植物叶片中重金属元素含量指示大气污染的研究

通过对潮州市区交通繁忙路段和对照区 (红山森林公园 )不同植物叶片重金属元素 (Pb、Cd、Cu、Zn)的含量研究 ,探讨了重金属含量与城市大气污染之间的关系。结果表明 ,植物叶片中的重金属元素富积量和大气中污染指数正相关。植物叶片的重金属元素富积量可较好和客观地指示市区大气的重金属污染状况。该研究为城市规划和环境保护提供了科学依据     

高岭土对焚烧烟气中Pb、Cd排放的控制特性研究

采用流化床焚烧炉进行焚烧实验,研究了烟气中颗粒物形态Pb和Cd的排放规律以及炉内添加高岭土粉末对Pb、Cd排放的影响。用低压冲击器分级采集颗粒物,原子吸收分光光度计检测Pb、Cd浓度,用扫描电镜/X射线衍射/能谱仪观察高岭土吸附重金属前后表面形貌和反应物的种类并检测表面元素分布。结果表明,PM10中90%以上的Pb和85%以上的Cd分布在亚微米颗粒物中;在焚烧炉内,Pb比Cd更易于向PM10中迁移。高温下高岭土与重金属Pb、Cd蒸气反应而产生共晶融化,随温度升高融化量逐渐增加。共晶融化可以促使颗粒相互黏附,促进亚微米重金属向粗颗粒中迁移。添加高岭土可以有效控制亚微米Pb、Cd排放,对亚微米Pb的最高吸附效率达83%,对亚微米Cd的最高效率达50%。高岭土对Pb吸附效率顺序为950℃1000℃850℃900℃;高岭土与Cd反应所需的温度较高,直至1000℃时才具有明显吸附效果。     

Determination of cadmium,mercury and lead in coal fly ash by slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry

Ultrasonic slurry sampling electrothermal vaporization isotope dilution inductively coupled plasma mass spectrometry (USS-ETV-ID-ICP-MS) has been applied to the determination of Cd, Hg and Pb in coal fly ash samples. Thioacetamide (TAC) was used as the modifier. Since the sensitivities of the elements studied in coal fly ash slurry and aqueous solution were quite different, isotope dilution method was used for the determination of Cd, Hg and Pb in these coal fly ash samples. The isotope ratios of each element were calculated from the peak areas of each injection peak. This method has been applied to the determination of Cd, Hg and Pb in NIST SRM 1633a coal fly ash reference material and a coal fly ash sample collected from Kaohsiung area. Analysis results of reference sample NIST SRM 1633a coal fly ash agreed satisfactorily with the certified values. The other sample determined by isotope dilution and method of standard additions was agreed satisfactorily. Precision was better than 6% for most of the determinations and accuracy was better than 4% with the USS-ETV-ID-ICP-MS method. Detection limits estimated from standard addition curves were in the range of 24–58, 6–28 and 108–110 ng g⁻¹ for Cd, Hg and Pb, respectively.     

Simultaneous sorption of benzene and heavy metals onto two organoclays

An experimental study was performed to determine the feasibility of using hexadecyltrimethylammonium bentonite clay (HDTMA-clay) and benzyltriethylammonium bentonite clay (BTEA-clay) for simultaneous sorption of benzene and one of four heavy metals (Pb, Cd, Zn and Hg). Specifically, the role of competition between benzene and each heavy metal was studied. The sorption of Pb, Cd, and Zn on both BTEA- and HDTMA-clay decreases in the presence of benzene relative to the sorption obtained without benzene present. This indicates that there is competition between Pb, Cd, and Zn and organic compounds during sorption onto both organoclays. On BTEA-clay, Cd, Pb and Zn sorption was reduced by 24, 37, and 51%, respectively. On HDTMA-clay, Cd, Pb, and Zn sorption was reduced by 25, 30, and 57%, respectively. Hg sorption was not affected either by the presence of benzene or by the organoclays used. The sorption of benzene onto BTEA-clay in the presence of Hg, Zn, Pb, and Cd was less than the sorption observed when no heavy metal was present. The presence of Hg resulted in the most significant decrease in sorption, causing a 59% reduction in benzene sorption. The presence of Zn, Pb, and Cd caused a 41, 35, and 31% reduction in benzene sorption, respectively. In general, sorption of benzene onto HDTMA-clay was not affected by the presence of the heavy metals, indicating there are no competitive effects observed with Zn, Cd, and Hg when HDTMA-clay was the sorbent. However, the presence of Pb did cause a 20% reduction in benzene sorption to HDTMA-clay. Both organoclays tested had dual sorptive properties for both heavy metals and an organic contaminant. While the competitive effects were greater for the BTEA clay, both organoclays are capable of simultaneously removing benzene and either Zn, Cd, Hg, or Pb from aqueous solution.     

Assessing spatial distribution,sources, and potential ecological risk of heavy metals in surface sediments of the Nansi Lake,Eastern China

The study is conducted to investigate the spatial distribution, sources and ecological risk of seven heavy metals in surface sediments of Nansi Lake, Eastern China. A total of 29 samples were collected in surface sediments of Nansi Lake, and were analyzed for three nutrients (TN, TOC and TP), two major metals (Al and Fe), as well as seven trace metals (As, Cd, Cr, Cu, Hg, Pb and Zn). The mean concentrations of As, Cd, Cr, Cu, Hg, Pb, Zn, Fe and Al were 14.41, 0.22, 71.10, 30.1, 0.048, 29.14, 90.2, 30,816 and 70,653 mg kg^?1, respectively, and the mean contents of these metals were higher than the background values with the exception of Cu and Fe. The spatial distribution indicated that the contents of all seven heavy metals were characterized by relatively higher contents in the upper lake than the lower lake. The hotspots with high values of As, Cd and Hg were associated with the river mouths, and the hotspots of Pb were mainly located around the dam in the central part, while no significant associations were displayed between spatial distribution of Cr, Cu, Zn and the river mouths. The mean enrichment factor (EF) values of As, Cd, Hg and Pb were 2.03, 2.93, 3.21 and 2.18, respectively, showing their moderate enrichment, while Cr, Cu and Zn with mean EF values of 1.19, 0.89 and 1.01 were deficiency to minimal enrichment. Multivariate and geostatistical analyses suggested that PC1 controlled by Cr, Cu and Zn was a lithogenic component, and come from parent rocks leaching. PC2 including Cd and partially Hg represented the factor from industrial wastewater discharge. PC3 showed elevated loadings of As and partially Cd, and could be attributed to the agricultural practices. While PC4 including Pb and partially Hg, was dominated by coal combustion. The results of potential ecological risk suggested that sediment environment of Nansi Lake suffered from high ecological risk.