Effects of hydrodynamics on the distribution of trace persistent organic pollutants and macrobenthic communities in Bohai Bay

In recent years, the rapid economic development along Bohai Bay, has brought out continuous increasing of the pollution loads in the Bohai Sea, especially by the large coastal reclamation project, Tianjin Binhai New Area. In the period of 2007-2009, we collected the sediments of the main rivers, estuaries, intertidal zone, and near-shore area of Bohai Bay, and Macrobenthos associated with the marine sediments to assess the influence of hydrodynamics in the coastal environment on the pattern of trace contaminants and the macrobenthic community. Based on data derived from these samples, the levels of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in sediments followed the order PAHs > OCPs > PCBs > PBDEs. The higher concentrations of PCBs, OCPs, PAHs and PBDEs were found in the estuarine and near-shore environment of the Dagu Drainage River. The spatial distribution of OCPs was different to that of PCBs due to the direction of the velocity field of Bohai Bay in its old and new topography, and the higher water-solubility of OCPs than that of PCBs. The results of the Pearson correlation and the PCA indicate that the medium diameter (MD) of sediments was the predominant factor influencing the distribution of PCBs and OCPs, most sampling sites were characterized mainly by TOC of sediments and biomass of macrobenthos. The results indicate that the distribution of trace contaminants and macrobenthic community in Bohai Bay are mainly affected by the hydrodynamic conditions.     

Sources of PCDD/Fs, non-ortho PCBs and PAHs in sediments of high and low impacted transboundary rivers (Belgium-France)

PAHs, PCDD/Fs and non-ortho PCBs have been assessed in Yser and Upper-Scheldt river sediments. Higher contamination levels were observed in the Upper-Scheldt sediments: maximum concentrations for the 16 US-EPA PAHs, PCDD/Fs and non-ortho PCBs respectively amount to 8.9 mg kg⁻¹, 12 ng TEQ kg⁻¹ and 5.1 ng TEQ kg⁻¹. Diagnostic PAH ratios in sediments and atmospheric samples suggest that the PAH compounds are from pyrolytic origin, more specifically combustion processes. The huge consumption of coal in cokes-ovens and smelters and its use for house-heating in Northern France, although decreasing during the last decades, are in support of that suggestion. PCDD/F fingerprints in sediments and deposition material indicate that OCDD is the dominant congener. In addition use of pentachlorophenol (PCP) in the past led to a minor contribution of PCDD/Fs in our sediment samples. Non-ortho PCBs form a substantial fraction of the total TEQ concentrations observed in the sediments. Since the 1980s and 1990s a substantial reduction of the PCDD/F sediment concentrations is observed, but this is not the case for the PAHs.     

冶金工业固体废物钢渣的综合利用

首先概述了钢渣的来源、化学组成及加工方法等;其次对钢渣的国内外综合利用途径进行了综述,分别介绍了利用磁选工艺回收废钢铁,作为冶金原料、建筑材料,以及在农业和水处理方面的应用特点和应用实例,并指出,在农业和水处理方面,钢渣具有广泛的应用价值和显著的社会经济效益;最后对钢渣综合利用的前景进行了展望,提出了加快钢渣资源化利用的建议。     

气相色谱法测定黄磷生产尾气中的CO_2

针对黄磷生产尾气具有强化学活性和腐蚀性的特点,选择了TDX-01型碳分子筛色谱柱,采用气相色谱法测定黄磷尾气中的CO2。实验结果表明:黄磷尾气中高浓度的CO2用TCD检测器检测,CO2体积分数在0.1%~10%时,检测下限可达到0.05%,方法的平均回收率为93.6%~104.1%,相对标准偏差为2.1%~3.2%;净化后黄磷尾气中的微量CO2经Ni催化甲烷化转化后用FID检测器测定,CO2体积分数在1.0×10-7~1.0×10-4时,方法的检测下限可达到5.0×10-8,相对标准偏差为1.63%。     

低含油污泥固化处理技术研究*

针对辽河油田欢采水厂低含油污泥,采用固化处理方法,测定了固化剂用量对抗压强度的影响和促凝剂用量对固化时间的影响,得到含油污泥:固化剂:促凝剂最佳配比为100:12:1.5。对含油污泥固化块进行浸出液毒性监测,分析结果表明:含油污泥固化块浸出液中重金属Cu、Pb、Cr、As、Zn、Ni、Cd的含量明显降低,远低于GB5085.3-2007《危险废物鉴别标准浸出毒性鉴别》;浸出液中COD降低了77%。     

城镇圩区排涝模数计算方法及其与河道调蓄库容关系研究

农业圩区原有的排涝模数计算方法已不适用于城镇圩区.针对城镇圩区的排涝特殊性,通过分析排涝计算的原理,充分考虑圩区内河道的调蓄能力,得到适应城镇圩区排涝计算的方法.以南京市江宁区为例,对城镇圩区的排涝模数进行计算,得到排涝模数与调蓄库容之间的定量关系.     

Utilization of washed MSWI fly ash as partial cement substitute with the addition of dithiocarbamic chelate

The management of the big amount of fly ash as hazardous waste from the municipal solid waste incinerator (MSWI) has encountered many problems in China. In this study, a feasibility research on MSWI fly ash utilization as partial cement substitute in cement mortars was therefore carried out. MSWI fly ash was subjected to washing process to reduce its chlorine content (from 10.16% to 1.28%). Consequently, it was used in cement mortars. Ten percent and 20% replacement of cement by washed ash showed acceptable strength properties. In TCLP and 180-day monolithic tests, the mortars with washed ash presented a little stronger heavy metal leachability, but this fell to the blank level (mortar without washed ash) with the addition of 0.25% chelate. Therefore, this method is proposed as an environment-friendly technology to achieve a satisfactory solution for MSWI fly ash management.     

麦芽糖醇的制备及其特性

麦芽糖醇是重要的糖醇制品之一,作为甜味剂、保湿剂、调味剂和加工助剂广泛应用于食品中。本文阐述了其热稳定性、溶解性、甜度、吸湿性、难发酵性、不升高血糖值、不刺激胰岛素的分泌等特性,最后对其发展前景进行了展望。     

Uptake of polycyclic aromatic hydrocarbons by Trifolium pretense L. from water in the presence of a nonionic surfactant

A greenhouse study examined plant uptake of phenanthrene and pyrene, as representatives of polycyclic aromatic hydrocarbons (PAHs), from an aqueous solution containing a nonionic surfactant Tween 80. The uptake was conducted with 1.0 mg l(-1) phenanthrene and 0.12 mg l(-1) pyrene under a wide range of Tween 80 concentrations (0-105.6 mg l(-1)). Tween 80 at the test concentrations did not show any apparent phytotoxity toward the growth of red clover (Trifolium pretense L.). At concentrations generally lower than 13.2 mg l(-1), Tween 80 enhanced the plant uptake based on the concentrations and PCFs (plant concentration factors) of these two PAHs. When present at higher concentrations, Tween 80 inhibited the uptake of both PAH compounds by the tested plant. The maximal plant uptake was observed at 6.6 mg l(-1) Tween 80, in which PAH concentrations and PCFs were 18-115% higher than those in Tween 80-free controls. The total mass removal (off-take) of phenanthrene and pyrene by root or shoot increased initially and decreased thereafter with the increase in Tween 80 concentrations. Although shoot biomass was evidently larger than root, the off-take was much higher in root than shoot because of the larger root concentrations of these chemicals. Results from this study show promises for the potential efficacy of enhanced phytoremediation in PAH contaminated sites using surfactant amendment.     

Distribution and sources of polycyclic aromatic hydrocarbons in surface sediments of rivers and an estuary in Shanghai, China

Concentrations, spatial distribution and sources of 17 polycyclic aromatic hydrocarbons (PAHs) and methylnaphthalene were investigated in surface sediments of rivers and an estuary in Shanghai, China. Total PAH concentrations, excluding perylene, ranged from 107 to 1707 ng/g-dw. Sedimentary PAH concentrations of the Huangpu River were higher than those of the Yangtze Estuary. The concentration of the Suzhou River was close to the average concentration of the Huangpu River. PAHs source analysis suggested that, in the Yangtze Estuary, PAHs at locations far away from cities were mainly from petrogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. In the Huangpu and Suzhou Rivers, pyrogenic input outweighed other sources. The pyrogenic PAHs in the upper reaches of the Huangpu River were mainly from the incomplete combustion of grass, wood and coal, and those in the middle and lower reaches were from vehicle and vessel exhaust.