集成电路生产中废气的污染及治理

介绍集成电路生产中产生各种废气的种类,废气中有害物质浓度及其危害性,并依据工程实践,评述了各类有害废气的各种处理方法。     

Emission of trace toxic metals during pulverized fuel combustion of Czech coals

A study of the trace elements emission (As, Se, Cd, Co, Cr, Cu, Zn, Hg, Tl, Pb, Ni, Sn, Sb, V, Mn and Fe) from pulverized coal combustion has been made at six heating and power stations situated in the Czech Republic. The amount of chlorine in coal has considerable influence on volatilization of some elements such as Zn, Cu, Pb, Hg and Tl, which is explained by the formation of thermodynamically stable compounds of these elements with chlorine. Generally, the affinities for Cl follows the order Tl > Cu > Zn > Pb > Co > Mn > Sn > Hg. The experimental data indicates enrichment of some of the trace toxic elements in the emissions (Cu, Zn, As, Se, Cd, Sn, Sb, Hg and Pb) and good agreement was obtained by thermodynamic equilibrium calculations with a few exceptions. In the case of Fe, Mn, Co, Cr and Sn calculated values are overestimated in the bottom ash and there are zero predicted amounts of these elements in the fly ash. In comparison, the results from experiments show up to 80% of these elements retained in fly ash. This implies that there exist additional steps leading to the enrichment by Fe, Mn, Co, Cr and Sn of small particles. Such mechanisms could include the ejection during devolatilization of small inorganic particles from the coal of bottom ash particles, or disintegration of the char containing these metals to small particles of fly ash. On the other hand, there are slightly overestimated or similar values of relative enrichment factors for As, V, Cu, Cd, Sb, Tl and Pb in the fly ashes and zero predicted values for bottom ashes. Our experimental results show about 5% or less of these elements are retained in bottom ashes, so they probably remain in the bottom ash inside unburned parts of coal. Copyright © 2003 John Wiley & Sons, Ltd.     

Effects of Contaminants on Toxicity of the Lampricides TFM and Bayer 73 to Three Species of Fish

Waters in the Great Lakes basin contain more than 400 contaminant chemicals that potentially affect fishery resources, commerce, and human inhabitants. We determined in the laboratory the effects of selected contaminants on the toxicity of the widely used lampricides TFM (3-trifluoromethyl-4-nitrophenol) and Bayer 73 (2′,5-dichloro-4′-nitrosalicylanilide) to three species of fish—rainbow trout (Salmo gairdneri), white sucker (Catostomus commersoni), and fathead minnow (Pimephales promelas). The fish were exposed to paired mixtures of lampricides and selected contaminants in standardized, acute static toxicity tests to determine the resulting type of response—less than additive, additive, or greater than additive (synergistic). As expected, the toxicities of combinations of lampricides with organic pesticides, metal, industrial or municipal pollutants, and tannic acid were mostly additive. However, the toxicity of a combination of TFM, Delnav, and malathion was synergistic, and extremely small quantities of each chemical became lethal when mixed. The concentration that produced 50% mortality was 1.64 mg/L for TFM alone but only 0.041 mg/L for TFM with the pesticides. Toxicities of the pesticides in the combination also increased commensurately. The triple combination of chemicals produced extraordinary synergism and effectively demonstrated the hazards that may result if certain chemical combinations occur in the aquatic environment. However, synergism is not the only kind of toxic action that produces hazards to aquatic organisms. All three types of toxic action are of concern because toxic units produced by contaminant chemicals add to the toxic units of applied management chemicals. Since the toxicity of the majority of chemical combinations is simply additive, this cumulative toxic action contributes more total units to aquatic environments than the extreme actions of less than additive and synergism. The toxicity of the lampricide TFM, as well as other management chemicals, is reinforced by the presence of any contaminant that contributes additional units of toxicity. Therefore, all types of cumulative toxic action should be of concern to people and agencies involved with protecting the environment.     

Organochlorine Contaminants of Wintering Ducks Foraging on Detroit River Sediments

Organochlorine analysis was performed on carcasses of 13 diving ducks from a 1981 wintering population that foraged on contaminated sediments in the lower Detroit River. Mean total PCB concentrations were 10 mg/kg for seven lesser scaups (Aythya affinis), 11 mg/kg for three greater scaups (A. marila), and 7.6 mg/kg for three goldeneyes (Bucephala clangula). Highest mean levels of other residues were measured for hexachlorobenzene (1.7 mg/kg) in goldeneyes, and transnonachlor (0.33 mg/kg) and 4,4’-DDE (1.3 mg/kg) in greater scaup. Quantitative analysis of 72 PCB congeners also was applied to water, seston, sediment, benthie oligochaetes, and carp from the same site. Principal congeners in most of the samples included some of the more toxic and persistent PCBs. Results of a multivariate analysis indicated that ratios of more conservative to less conservative PCBs did not vary significantly among ducks (α = .05), but differed from those in carp, oligochaetes, and sediment. For the February through March period of fat mobilization, concentrations of total PCB in lipid were inversely correlated with percent lipid (r = 0.76) in ducks. The percentage of conservative PCBs increased slightly. The distribution and partitioning of organochlorines, including toxic PCB congeners, varied considerably within this water column-sediment-fauna ecosystem. Estimates of toxic exposure based on total PCB values may be unreliable.     

用于吸附贵重金属、有色金属、有毒金属及稀有金属的有机硅吸附剂

概述了有机硅吸附剂的结构、类型及其官能团的种类与被吸附元素的关系,详细介绍了用于吸附贵重金属、有色金属和有毒金属、稀土元素及放射性元素的有机硅吸附剂的官能团种类及其吸附特性,以及在化工废水、冶金污水、腐蚀性废水的无害化处理中的应用。     

一种压缩待测气体增强气体传感的方法

针对普通气体传感器在低体积分数的气体检测中灵敏度低的问题,提出将待测气体进行压缩以增强气体传感器响应的方法,根据检测压缩后的气体响应的特征,间接得到普通状态下该气体的体积分数。设计了一种小型的样机系统来进行气体压缩和气体传感器检测,描述了系统各个模块的设计,给出了该系统的软件设计和控制流程。以H2S气体为检测对象进行了实验,分析结果表明:该方法提高了现有传感器检测低体积分数气体的能力,尤其是提高了对毒害气体的及时发现和预警防范能力。样机的试制也为该压缩传感系统的进一步小型化和提升检测性能提供了条件,具有较高的应用价值。     

关注选治药剂中的有毒有害物质

选冶药剂中存在多种高关注度物(SVHC),它们是具有致癌、致畸及生殖毒性的物质(CMR),具有持久性、生物累积性、毒性物质(PBT),具有高持久、生物累积性物质(v Pv B)。此外选冶药剂中还有定义为新型污染物、POPs、内分泌污染物、冶炼中的二恶英全合成的前体物及大量的致癌及可能致癌的有毒有害物。但人们对其缺乏认知及法规监管。与SVHC、PBT等单一污染不同的是选冶药剂有毒有害物质污染与全球最大最持久的重金属污染的交叉、叠加与复合。     

制冷工质燃烧(分解)及生成有毒气体的探讨

2010年6月以来,德国联邦材料研究与测试所(BAM)声称R1234yf暴露于点火源后会生成有毒HF气体,危害人身健康.2010年末国内也有对R32表达同样疑虑的反映.为此,从化学反应动力学原理、从生成有毒气体的种类及其允许暴露极限、并参考SAE研究成果等几方面,对BAM报告进行了探讨和分析,得出了一些看法,其中特别是从它们试验结果发现,在相同背景下凡是R1234yf导致生成HF浓度超标的,R134a也超标,这就说明了这个问题不足以构成它们应用的障碍;并有理由认为:即使在极端恶劣条件下,R32的HF和可燃风险概率也将分别小于或等于R1234yf(R134a)的10-122和10-14量级,处于极低的风险水平.     

ICP-MS法测定白酒中Mn和毒理性元素的研究

建立电感耦合等离子体质谱（ICP-MS）法测定白酒中Mn和9个毒理性元素含量的分析方法。白酒采用硝酸酸化并加入低浓度盐酸后测定了其中的Be、Cr、Mn、Ni、As、Cd、Sn、Sb、Hg、Pb等元素,盐酸的加入有效地改善了样品溶液中元素的长时间稳定性,尤其是元素Hg和Sn。应用八极杆碰撞/反应池（ORS）技术有效地消除了盐酸的使用所带入的氯离子干扰以及其他质谱干扰,采用基体匹配并通过加入内标溶液有效地补偿样品传输的影响以及溶剂蒸发速率的差异,消除了基体所产生的影响。在选定的工作条件下,方法的线性关系良好,各元素的检出限为0.13¹2.15 ng/L之间,相对标准偏差（RSD）在0.75%³.48%之间,样品的加标回收率为93.80%¹10.00%。该方法具有操作简单、快速、结果准确等特点,可用于白酒的质量控制和安全评价。      

Toxic (Pb,Cd, Hg) and essential (Fe,Cu, Zn,Mn) metal content of liver tissue of some domestic and bush animals in Ghana

Accumulation of toxic metals in liver, a rich natural source of essential elements, can present health risks to regular consumers of liver. A total of 35 fresh liver samples of cow, sheep, goat, pig, grass-cutter (Thryonomys swinderianus), gaint rat (Cricetomys gambianus), red deer (Cervus elaphus), chicken and antelope (Antilocapra americana) were obtained from three different markets in Accra and Kumasi, Ghana. Samples were analyzed using atomic absorption spectrometry and an automatic mercury analyzer. Levels of iron in the grass-cutter and pig of 500.5–645.4 mg kg^?1 were the highest in the animal livers examined. Mn concentrations were highest in grass-cutter and rat liver, ranging 16.5–30.2 mg kg^?1. The safe Cu and Zn permissible limits of 20 and 50 mg kg^?1 were exceeded in 70 and 75% of the liver samples, respectively. Generally, for each animal group studied, at least 50% of the sample livers exceeded the Cd permissible limit of 0.5 mg kg^?1. The levels of Pb, which ranged 1.3–13.8 mg kg^?1, exceeded the proposed European Commission (EC) limit of 0.5 mg kg^?1. Care must be taken by regular consumers of the iron-rich animal livers of grass-cutter, pig and rat because they also had the highest levels of Pb (in grass-cutter and pig) and Cd (in grass-cutter, rat and pig). The liver samples analyzed for Hg had values far below the permissible limit of 0.5 mg kg^?1.