管式反应器石灰雾液脱硫的数学模拟

建立的一维管式反应器雾液脱硫模型是对蒸发和吸收过程的耦合，以膜理论为基础的吸收机理同时考虑了含硫组分的离解、扩散、反应和固体颗粒的溶解。参数敏感性分析表明，对系统脱硫率影响最显的是出口干湿球温差，石灰颗粒粒度和入口ＳＯ２浓度、传质过程的分析表明，反应开始阶段液膜扩散和固体溶解阻力均存在，而气膜扩散在整个反应过程中都起着重要作用。     

矿井水中天然总α放射性的混凝处理技术研究

本文研究了混凝沉淀工艺处理矿井水中天然总α放射性核素铀、镭的技术和条件,通过选择适当的混凝剂、加药量、pH值等条件可将铀的去除率提高到80％左右,使用铀专用混凝剂MHU则可使铀的去除率达到87％。对于镭的去除不能单纯依靠铀混凝剂MHU,尚需添加镭的吸附助剂MHR,则可使镭的去除率提高到80％以上。该工艺的最大优点在于充分利用了煤矿现存的大量矿井水悬浮物处理设施,大大节省了新建工程的投资费用,而且新增加的药剂费用不足0.1元/t水,可在煤矿推广应用。     

溢油指示物(指标)HPLC-UVD研究

建立了溢油指示物（ 指标）ＨＰＬＣ—ＵＶＤ 相似性模式，给出了溢油指示物（ 指标）ＨＰＬＣ—ＵＶＤ 相似性的择近原则，指出溢油指示物（ 指标）ＨＰＬＣ—ＵＶＤ相似性主要受控于油种、风化和实验误差等因素的影响。结果表明，ＨＰＬＣ—ＵＶＤ 相似性模式可作为溢油指示物（ 指标） 。     

垃圾焚烧烟气中HCl与消石灰的反应机理研究

测试了两种消石灰与垃圾焚烧烟气中HCl的反应率,得出了消石灰的反应率与反应时间的反应曲线,分析了消石灰与HCl的反应机理及影响消石灰最终反应率的因素。试验结果表明,消石灰与HCl反应初期按灰层扩散控制进行,两种消石灰的最终反应率分别为16％和36％。     

双效精馏-吸附联合工艺处理DMF废水

提出以双效精馏-吸附联合工艺处理DMF废水。采用双效精馏将DMF废水中的DMF回收为99.8%以上的产品;采用大孔树脂对双效精馏后产生的少量DMA和DMF进行吸附,使其达到国家排放标准,并例举了该工艺在工程上的应用实例。     

毒死蜱对我国南方稻区水域中12种淡水鱼的毒性

毒死蜱作为稻田常用农药,普遍存在于稻区沟渠、池塘和河流中,从而对生活在其中的鱼类具有潜在风险。通过短期暴露试验,比较了毒死蜱在纯水、水-沉积物体系中对淡水鱼的毒性效应,进一步研究了毒死蜱在不同鱼体内的生物富集作用,以及对鱼脑Ach E活性的影响。试验结果表明:毒死蜱对12种淡水鱼均表现为高毒或剧毒,最敏感的是太阳鱼,但体系中沉积物的存在会通过吸附作用降低农药对鱼类的毒性;毒死蜱在鱼体内表现为中等或高富集性,其中斑马鱼的富集系数最大;毒死蜱对鱼脑Ach E酶活性有明显抑制作用,其中以虹鳟最敏感。研究结果为稻田常用农药对水生态环境中鱼类安全的风险性评价提供了科学依据。     

Effects of an iron-silicon material,a synthetic zeolite and an alkaline clay on vegetable uptake of As and Cd from a polluted agricultural soil and proposed remediation mechanisms

Economic and highly effective methods of in situ remediation of Cd and As polluted farmland in mining areas are urgently needed. Pot experiments with Brassica chinensis L. were carried out to determine the effects of three soil amendments [a novel iron-silicon material (ISM), a synthetic zeolite (SZ) and an alkaline clay (AC)] on vegetable uptake of As and Cd. SEM–EDS and XRD analyses were used to investigate the remediation mechanisms involved. Amendment with ISM significantly reduced the concentrations of As and Cd in edible parts of B. chinensis (by 84–94 % and 38–87 %, respectively), to levels that met food safety regulations and was much lower than those achieved by SZ and AC. ISM also significantly increased fresh biomass by 169–1412 % and 436–731 % in two consecutive growing seasons, while SZ and AC did not significantly affect vegetable growth. Correlation analysis suggested that it was the mitigating effects of ISM on soil acidity and on As and Cd toxicity, rather than nutrient amelioration, that contributed to the improvement in plant growth. SEM–EDS analysis showed that ISM contained far more Ca, Fe and Mn than did SZ or AC, and XRD analysis showed that in the ISM these elements were primarily in the form of silicates, oxides and phosphates that had high capacities for chemisorption of metal(loid)s. After incubation with solutions containing 800 mg L^?1 AsO₄ ^2? or Cd²⁺, ISM bound distinctly higher levels of As (6.18 % in relative mass percent by EDS analysis) and Cd (7.21 % in relative mass percent by EDS analysis) compared to SZ and AC. XRD analysis also showed that ISM facilitated the precipitation of Cd²⁺ as silicates, phosphates and hydroxides, and that arsenate combined with Fe, Al, Ca and Mg to form insoluble arsenate compounds. These precipitation mechanisms were much more active in ISM than in SZ or AC. Due to the greater pH elevation caused by the abundant calcium silicate, chemisorption and precipitation mechanisms in ISM treatments could be further enhanced. That heavy metal(loid)s fixation mechanisms of ISM ensure the remediation more irreversible and more resilient to environmental changes. With appropriate application rate and proper nutrients supplement, the readily available and economic ISM is a very promising amendment for safe crop production on multi-metal(loids) polluted soils.     

Assessment of leaching behavior and human bioaccessibility of rare earth elements in typical hospital waste incineration ash in China

Leaching behavior and gastrointestinal bioaccessibility of rare earth elements (REEs) from hospital waste incineration (HWI) fly and bottom ash samples collected from Beijing and Nanjing Cities were assessed. In the same ash sample, the leaching concentrations of individual REEs determined by the Toxicity Characteristic Leaching Procedure (TCLP) were higher than those detected by the European standard protocol (EN-type test), thereby suggesting that the low pH value of leaching solution was an important factor influencing the leachability of REE. The REE bioaccessibility results, which were evaluated using the physiologically based extraction test (PBET), indicated that REEs were highly absorbed during gastric phase by dissolution; and subsequently precipitated and/or re-adsorbed in small intestinal phase. The relative amounts of the total REEs extracted by the TCLP method, EN-type test and PBET test were compared. In addition to the pH value of extraction solutions, the chelating role of REEs with organic ligands used in the PBET method was also an important parameter affecting REE adsorption in human body. Additionally, this study showed that REEs were extracted by these methods as concomitants of heavy metals and anions (NO₃ ^–, F^–, SO₄ ^2–, and Cl^–) from HWI ash, which probably caused the remarkably complex toxicity on human body by the exposure pathway.

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Dynamic fate modeling of γ-hexachlorocyclohexane in the lower reaches of the Liao River

A QWASI model dependent on temperature is parameterized to describe the long-term fate of persistent organic pollutants (POPs) in the Liao River. The model parameters, namely fugacity capacity, degradation rate, and transfer coefficient, are profoundly affected by temperature. This model is used to simulate the fate of γ-hexachlorocyclohexane (γ-HCH) in the lower reaches of the Liao River from 1998 to 2008. Modeling results show that γ-HCH fugacity capacities in air, water, and sediment increase as temperature decreases, and the transfer and transformation rate coefficients increase as temperature increases. The variations of transfer and transformation parameter D values depend on fugacity capacities, and transfer and transformation coefficients simultaneously. The performance of the model is evaluated by comparing the predicted and observed concentrations in the water and sediment of the Liao River. The predicted values agree well with the observed value in the order of magnitude, in most cases within the factor of 3. It is believed that the model is appropriate for simulating the long term fate of POPs in the Liao River. Translated from Environmental Science, 2006, 27(1): 121–125 [译自: 环境科学]     

GIS在环境监测数据管理分析中的应用

根据环境监测的特点和地理信息系统(GIS)所具备的功能,讨论了GIS与环境监测结合的必要性,按照环境监测的目的不同分环境质量监测、污染源监督监测和应急监测三个方面阐述GIS在环境监测数据管理分析中的具体应用,并利用现有的一些基于GIS的环境监测信息系统实例进行进一步说明GIS在环境监测数据管理分析中的应用,充分发挥了GIS空间信息表达处理及综合分析的优势,使得环境监测数据的管理分析更加快速、实时、有效.随着GIS技术的发展,GIS在环境监测数据管理分析中的应用也将获得源源不绝的驱动力.