剩余污泥的资源化利用

随着社会的不断发展,大量剩余污泥的产生将不可避免,剩余污泥的处理也因此成了一个非常棘手的问题。针对传统剩余污泥处理方法的种种弊端提出的污泥资源化利用技术,是符合当今社会可持续发展战略的。本文简单介绍了目前剩余污泥资源化技术的状况,着重介绍了污泥制备吸附剂和碳基催化剂的技术,同时对今后剩余污泥资源化发展提出了几点建议。     

植物净化空气中汞污染的研究

对上海市常见易生长的22种植物进行了现场采样测试，结果发现，瓜子黄杨、广玉兰、海桐、蚊母、墨西哥落叶杉及棕榈对汞蒸气具有很强的吸收富集能力及抗毒性能．然后采用富集能力最强的瓜子黄杨进行一系列试验，结果显示，汞浓度随接触瓜子黄杨时间的延长而降低，而瓜子黄杨叶片的汞含量随时间的延长而增加。根据吸汞实验，计算得瓜子黄杨叶面积的吸气速率为0.133m     

冷原子荧光法测定水样中痕量汞的条件

本文讨论了冷原子荧光法测定水样中微量、痕量和超痕量汞的最佳条件，玻璃器皿的洗涤方法、试剂和纯水的质量、以及仪器参数的选择等对测定结果的影响。     

氧瓶燃烧法与冷原子吸光光度法测定煤中痕量汞

本文介绍了以氧瓶燃烧法处理煤样,氯化亚锡还原汞离子,用冷原子吸收法测定汞的含量。同时,对氧瓶燃烧法处理煤样的可靠性进行了考察。     

生物体内汞与硒的相互作用

对硒与汞在生物体内相互作用的一般规律进行了综合评述，概括介绍了生物体内汞与硒相互拮抗关系的实验研究基础，汞与硒拮抗作用的影响因素以及汞与硒拮抗机制的研究进展。     

Short-term effects of environmental factors on the asexual reproduction of Aurelia sp. polyps

ABSTRACT

Aurelia is a jellyfish genus common in coastal and estuarine habitats, that are typically affected by human pressures such as heavy metals contamination. Mercury is one of the most dangerous due to its high toxicity, persistence and bioaccumulation. In this paper, we tested for the first time the independent and combined effects of a level of mercury allowable by European regulation in force and hyposalinity on the asexual reproduction of Aurelia sp. polyps, mirroring a realistic scenario. Both mercury (0.07?µg/L, Maximum Allowable Concentration) and salinity (18 and 23 PSU) and the combination of the two factors stimulated the asexual reproduction increasing the number of polyps and buds during the 41 days of experiments. The increment of the asexual reproduction and the absence of suffering and mortality suggest that levels of mercury below the concentration fixed by the law and hyposalinity conditions could promote jellyfish proliferations, according to the hormesis hypothesis.     

我国煤中汞含量水平及洗选过程汞流向分析

介绍了我国煤中汞含量与分布特征、煤中汞的赋存形态,分析了汞释放对环境的影响以及汞的脱除与控制技术。结果表明:我国(华南)晚三叠世(T3)煤中汞含量最高,平均含量为0.26μg/g;贫煤和无烟煤中汞含量最高,平均含量都超过0.20μg/g。含汞较高的晚三叠世、晚二叠世煤田主要分布于华南各地;多数煤中汞含量在0.300μg/g以下,但华南的江西、广西、贵州等地煤中汞含量总体水平较高;汞的赋存形态可分为有机结合态和无机结合态,煤中汞的控制方法可分为利用前脱汞、利用(燃烧)后脱汞和过程中汞形态转化。提出了煤炭洗选过程汞分布、脱除率和汞平衡等计算公式,指出了煤炭洗选过程中汞迁移行为的主要影响因素。     

Arctic source for elevated atmospheric mercury (Hg0) in the western Bering Sea in the summer of 2013

Measurements of gaseous elemental mercury(Hg~0) in the marine boundary layer of the western Bering Sea were performed using an automatic mercury analyzer RA 915 +(Ltd. "Lumex", St. Petersburg, Russia) aboard the Russian research vessel Academician M.A.Lavrentev from 3 to 20 August 2013. Hg~0 concentrations varied from 0.3 to 2.1 ng/m~3(n = 4783);the average value(1.1 ± 0.3 ng/m~3) was lower than both the background range of the Northern Hemisphere(1.5–1.7 ng/m~3) and average values previously observed in the Bering Sea, and corresponded to the background concentrations of the Southern Hemisphere(1.1–1.3 ng/m~3).Maximum Hg~0 concentrations were observed within air masses that came from the lower troposphere of the central Arctic. Under these conditions, Hg~0 ranged between 1.1 and 2.1 ng/m~3 with an average of 1.5 ± 0.2 ng/m~3(n = 1183). Except for these periods, Hg~0 concentrations during the rest of the study varied from 0.3 to 1.8 ng/m~3, with an average value of 1.0 ± 0.2 ng/m~3(n = 3600). Our results support the hypothesis that, in the summer, air masses from the central Arctic Ocean can be an exporter of mercury to lower latitudes. Perhaps the atmospheric transport of elevated concentrations of Hg~0 into lower latitudes may have implications for the biologic and economic health of important fisheries, such as the Bering Sea.     

Characteristics of mercury desorption from sorbents at elevated temperatures

This study investigated the dynamic desorption characteristics of mercury during the thermal treatment of mercury-loaded sorbents at elevated temperatures under fixed-bed operations. Experiments were carried out in a 25.4 mm ID quartz bed enclosed in an electric furnace. Elemental mercury and mercuric chloride were tested with activated carbon and bauxite. The experimental results indicated that mercury desoption from sorbents was strongly affected by the desorption temperature and the mercury–sorbent pair. Elemental mercury was observed to desorb faster than mercuric chloride and activated carbon appeared to have higher desorption limits than bauxite at low temperatures. A kinetic model considering the mechanisms of surface equilibrium, pore diffusion and external mass transfer was proposed to simulate the observed desorption profiles. The model was found to describe reasonably well the experimental results.     

High mercury leachate containing HgS22 − complex ion: Detoxifying solidification and high efficiency Hg extraction

Clean and efficient treatment of high-mercury leachate produced from remediation of mercury-polluted soil has become a huge challenge for environmental scientists.In this work,cement solidification was firstly adopted to treat the high-concentration mercury leachate,which had high alkalinity.Different mercury concentrations,namely 3.120 mg/L Hg mercury leachate and 9.243 mg/L Hg mercury concentrated leachate,were separately solidified by Portland cement.The results indicated that simply using the cement can properly solidify both the leachates to meet the waste landfill standard,with liquid(mL)/solid(g) ratio(L/S ratio) of4:10–6:10.In order to make full use of mercury in the leachates,a Hg extraction method was subsequently carried out under different experimental parameters,such as temperature and p H value.It was shown that the Hg extraction ratio could reach as high as 99.84% and almost all the mercury in the leachate could be transformed to HgS precipitate;moreover,the Hg concentration in the treated leachate was reduced from 3.120 to 0.005 mg/L at p H 2.98 and 30°C,which was much less than the limit of the national standard,indicating that the leachate had been completely cleaned and could be discharged freely.Hence,simple cement solidification renders high-mercury leachate nontoxic,and the Hg extraction method can successfully recover the Hg and enable the residual leachate to be discharged safely.