煤飞灰多环芳烃环境标准参考物的研制与定值

研制了一种煤飞灰多环芳烃（ＰＡＨｓ）环境标准参考物，用高效液相色谱ＨＰＬＣ（ＵＶＤ／ＦＬＤ）作为分析方法，对其均匀性和稳定性进行了检验，对几种有代表性的ＰＡＨｓ的分析统计结果表明，其均匀性是合格的，在－２５℃保存时，稳定性在两年以上，采用两种独立可靠的方法（提取－直接进样ＨＰＬＣ和提取－硅胶柱预分离－ＨＲＧＣ），给出了煤飞灰参考物质中几种ＰＡＨ的定值结果：菲（ＰＨ）７．１±２．６μｇ／ｇ，蒽（ＡＮ     

(Z)-11-Pentacosene is the major sex pheromone component inDrosophila virilis (Diptera)

Summary A crude cuticular extract from 3450 virgin 9–13 day old female fruit flies(Drosophila virilis), was subjected to chromatography accompanied by bioassay for sex pheromone activity. After three chromatographic steps, fractions containing active monoenes and dienes were obtained. Chemical analysis by infrared absorption, gas liquid chromatography and gas chromatography/mass spectrometry of the active fraction indicated that active monoenes were comprised chiefly of (Z)-11-pentacosene (abbreviated (Z)-11-C_25:1), (Z)-13-C_27:1, (Z)-13- and (Z)-14-C_29:1. Synthetic monoenes were made, and only (Z)-11-C_25:1 elicited good courtship behaviour in maleD. virilis. Therefore it was concluded that (Z)-11-C_25:1 was a major sex pheromone. A total of 16.2±1.32 µg of cuticular hydrocarbons was isolated from 10 day old females, including 5.9±0.56 µg of (Z)-11-C_25:1. An additive effect was suggested from the higher observed courtship response when using a mixture of active dienes with the active monoene.     

TROPHIC LEVEL ACCUMULATION OF HEAVY METALS IN A COAL ASH BASIN DRAINAGE SYSTEM1

ABSTRACT: The uptake of ten chemical elements was measured in water, sediment, fly ash, and the major biotic components of an ash basin drainage system. The biota tested represent several trophic levels observed in the settling basin and receiving swamp of the system. Concentrations were measured by neutron activation (NAA) in the major biotic groups including aquatic bacteria, algae, macrophytes, midges, dragonflies, crayfish, tadpoles, and fish. Only three elements (Cu, Zn, Cd) were more highly concentrated in water from a nearby unpolluted stream than in the fly ash effluent. Sediment concentrations of all elements were highest in the ash drainage system with Al and Fe being consistently highest. Among the biota, Hydrodictyon sp. and Lemna perpusilla had the highest concentrations of Al and Fe while other macrophytes were the major accumulators of Mn and Ba. Invertebrates generally concentrated high amounts of Cu and Zn although Cd and Hg were accumulated most by crayfish. Selenium was selectively concentrated by bacteria, crayfish (Procambarus sp.) and mosquitofish (Gambusia afflnis). Consequences of elemental concentrations in sediment and in specific trophic level groups are discussed.     

RESPONSES OF HETEROTHROPHIC BACTERIAL POPULATIONS TO pH CHANGES IN COAL ASH EFFLUENT1

ABSTRACT: Total culturable heterotrophic bacteria in a coal ash basin and drainage system were monitored over a period of two years. In the first year heavy (bottom) ash was sluiced to the basin resulting in a pH of 6.5. During the second year fly ash was precipitated and added to the sluice lowering the basin pH to 4.6. Sulfate concentrations during 1975 ranged from 16–73 ppm (mean 33) and in 1976 from 44–88 ppm (mean 72). Mean annual basin temperatures were 28.8 and 26.0 C, respectively. Approximately 1500 m in the receiving swamp below the basin, mean pH and temperature were 6.8 and 22.2 C for the first year, and 5.4 and 22.1 C for the second. Total culturable bacteria and diversity (colony types) were reduced at all sampling stations by 44 and 30 percent, respectively, whereas the percentage of the population comprised of chromagenic bacteria increased by 51 percent at the lower pH; Data indicated the pH had a greater effect than did water temperature when temperature was within the range of 15–25 C. The predominant genera within the system in the first year were Bacillus, Sarcina, Achromobacter, Flavobacterium, and Pseudomonas. In the second year, at the lower pH, predominant genera were Pseudomonas, Flavobacterium, Chromobacterium, Bacillus, and Brevibacterium.     

高活性脱硫剂脱硫工艺的实验研究

对以粉煤灰为原料制备的高活性脱硫剂进行了半干法烟气脱硫实验研究，考虑添加剂、脱硫剂加入量、反应温度、烟气流量工艺因素的影响时该活性脱硫剂的脱硫性能；实验结果表明，加入添加剂后，脱硫效率提高1．5％～8．1％；当烟气流量〈2m^3／min，钙硫比取1．5—2．0范围时，脱硫效率较高；一定范围内反应温度变化对脱硫效率影响不大。     

Leaching of PCDD/F from fly ash and soil with fire-extinguishing water

Leaching experiments from fly ash and soil with fire-extinguishing water result in significant amounts of PCDD/F in the related leachates. In contrast to the water solubilities the higher chlorinated congeners are leached more easily than the low chlorinated tetra- and penta-congeners. Obviously, the cosolvents present in the fire-extinguishing water enhances PCDD/F solubilities.     

粉煤灰资源化的现状

本文检索了国内外综合利用粉煤灰的有关文献 ,由粉煤灰特性入手 ,介绍了它在农业、建筑、环保等行业的资源化现状。指出粉煤灰作为二次资源的重要意义 ,并对粉煤灰资源化提出了一些设想     

污泥焚烧底灰中重金属残留特性的实验研究

利用原子吸收分光光度计和程序控制温升炉研究了沈阳市污水处理厂污泥在不同焚烧工况下重金属Cu、Cr、Cd、Zn、Ni和Pb在焚烧底灰中的残留特性。考察了升温速率、焚烧温度、含水率以及停留时间等因素对重金属在污泥底灰中的残留特性的影响。实验表明 ,Pb、Cd和Cu在灰渣中的残留率随着温度和停留时间的增加而降低。大部分的重金属元素Zn、Cu和Cr残留在灰渣中 ,Cd、Pb和Ni部分残留在灰渣中     

超细粉煤灰-氟石膏在道路修补工程中的综合利用研究

针对我国现有水泥混凝土路面的破坏问题,研究开发了以工业废料--超细粉煤灰和氟石膏为主要组分的水泥基道路修补材料,利用氟石膏与超细粉煤灰在水泥水化过程中的相互激发作用,通过试验优选出超细粉煤灰-氟石膏高性能道路修补材料,并应用于道路修补混凝土的配制,同时测试了其力学性能及部分长期性能,试验表明其性能优良,在此基础上对其水化硬化机理作了初步的探讨.     

Reaction of arsenic vapor species with fly ash compounds: kinetics and speciation of the reaction with calcium silicates

In coal combustion systems, the partitioning of arsenic between the vapor and solid phases is determined by the interaction of arsenic vapors with fly ash compounds under post-combustion conditions. This partitioning is affected by gas–solid reactions between the calcium components of the ash particles and arsenic vapors. In this study, bench scale experiments were conducted with calcium compounds typical of coal-derived fly ash to determine product formation, the extent of reaction and reaction rates when contacted by arsenic oxide vapors. Experiments conducted with arsenic trioxide (As₄O_6(g)) vapors in contact with calcium oxide, di-calcium silicate and mono-calcium silicate over the temperature range 600–1000 °C indicated that these solids were capable of reacting with arsenic vapor species in both air and nitrogen. Calcium arsenate was the observed reaction product in all the samples analyzed. Maximum capture of arsenic occurred at 1000 °C with calcium oxide being the most effective of the three solids over the range of temperatures studied. Using a shrinking core model for a first order reaction and the results from intrinsic kinetic experiments conducted in air, the reaction rate constants were found to be 1.4×10⁻³exp(−2776/T) m/s for calcium oxide particles, 7.2×10⁻³exp(−3367/T) m/s for di-calcium silicate particles and 5.5×10⁻³exp(−3607/T) m/s for mono-calcium silicate particles. These results therefore suggest that any calcium present in fly ash can react with arsenic vapor and capture the metal in water-insoluble forms of the less hazardous As(V) oxidation state.