CuCl2改性飞灰吸附气相零价汞

采用CuCl₂对循环流化床锅炉飞灰进行改性,在固定床反应器上对CuCl₂改性飞灰进行了气相零价汞（Hg⁰）吸附实验。考察了CuCl₂负载量和吸附温度对改性飞灰Hg⁰吸附能力的影响,并结合颗粒内扩散模型、准一阶动力学模型、准二阶动力学模型和耶洛维奇模型拟合结果分析该过程的控制步骤。结果表明： CuCl₂改性飞灰的Hg⁰穿透时间远大于未改性飞灰,对Hg⁰的吸附量随CuCl₂负载量的增加而增加;CuCl₂改性飞灰的Hg⁰吸附能力随吸附温度的升高先增大后减小,150 ℃为最佳吸附温度;准二阶动力学模型的拟合值与实验值相关系数最高,且该模型初始吸附速率与实验值最为接近,即准二阶动力学模型更适合于描述CuCl₂改性飞灰的Hg⁰吸附过程。     

Delineation of groundwater contamination around an ash pond: geochemical and GIS approach

The study has investigated the levels of metal contamination in groundwater due to particulate matter fallout and leaching from ash pond and assigned contamination indices for the adjacent localities around an ash disposal site with application of geographic information systems (GIS). Fe, Ba, Cu, Mn, S, Pb, V, and Zn were found to be the major contaminants in groundwater. Enrichment factors (EF) of these elements with respect to the United States Environmental Protection Agency (USEPA) maximum contaminant levels show high values for Mn, Fe, and Pb in groundwater. The zone of attenuation for Ba, Fe, Cu, Mn, S, and Zn in groundwater is about 600-900 m from the ash pond, while Pb did not show any significant attenuation even at a distance of 1200 m. Tube wells around Rankasingha and Kukurhanga villages are most contaminated whereas open wells of Lachhmanpur, Kaniapada, and Kurudul villages showed higher degrees of contamination.     

海上采油油轮增设油气分离装置的探讨

胜利油田海上边际油井受环境条件的制约,安装采油的油气分离装置也较简单;由此产出的原油中含有20%天然气进入油轮,给整个采油的油轮带来危险并给操作人员带来危害。在采油油轮上增设油气处理装置后,既改善了油轮操作人员的工作环境,消除了油轮事故隐患,又节约了在原平台上增设油气分离设施的费用,保护了采油油轮操作者的安全与健康,保障了安全生产。笔者依据胜利油田海上采油油轮的生产作业状况,论述在采油油轮上增设油气分离装置的必要性,并对所增设的设备及施工条件作了初步探讨。同时还论证了海上采油油轮增设油气分离装置,是改善操作人员的工作环境和消除事故隐患的必要措施。     

粉煤灰复合材料砖的研制

提出了在常温下以粉煤灰为主要原料，研制高强度复合材料的方法。探讨了物料的成分配比、混料、成型和干燥的过程参数，并确定了材料的各项性能指标。     

在高压射流喷沙系统中高效节能水沙分离器的研究与应用

在高压射流喷沙系统中，采用水沙分离器进行水处理，能够清除粒径大于１０ｕｍ的金刚沙。经过处理的水能够重复利用，满足高压射流对水质的要求。     

Use of created cattail (Typha) wetlands in mitigation strategies

In order to balance pressures for land-use development with protection of wetland resources, artificial wetlands have been constructed in an effort to replace lost ecosystems. Despite its regulatory appeal and prominent role in current mitigation strategies, it is unclear whether or not created systems actually compensate for lost wetland resources. Mitigation predictions that rely on artificial wetlands must be analyzed critically in terms of their efficacy. Destruction of wetlands due to burial by coal fly ash at a municipal landfill in Danvers, Massachusetts, USA, provided an opportunity to compare resulting growth of created cattail (Typha) marshes with natural wetland areas. Once the appropriate cattail species was identified for growth under disturbed landfill conditions, two types of artificial wetlands were constructed. The two systems differed in their hydrologic attributes: while one had a surface water flow characteristic of most cattail wetlands, the second system mimicked soil and water conditions found in naturally occurring floating cattail marshes. Comparison of plant growth measurements for two years from the artificial systems with published values for natural cattail marshes revealed similar structure and growth patterns. Experiments are now in progress to investigate the ability of created cattail marshes to remove and accumulate heavy metals from polluted landfill leachate. Research of the type reported here must be pursued aggressively in order to document the performance of artificial wetlands in terms of plant structure and wetland functions. Such research should allow us to start to evaluate whether artificial systems actually compensate for lost wetlands by performing similar functions and providing the concomitant public benefits.     

PHOSPHATE IN WATERS: II. PLANT AVAILABILITY OF LIGNITE FLY ASH EXTRACTED FORMS IN GREENHOUSE TRIALS1

ABSTRACT: Orthophosphate P was removed from municipal waste water, lake waters, and P-spiked solutions by contact with fly ash from lignite burning electric power generating plants. The recovered ash was increased in total P content 3-fold, and Bray No. 1 soluble P, 9-fold. Phosphorus enriched ash so prepared was used in greenhouse trials with sand or soil as the major substrate material. Recovery of added P by barley plants ranged from 3 to 26 percent in the sand cultures and from 2 to 17 percent for soil cultures. Phosphorus contained in normal ash was partially available to barley under the conditions of these experiments. High B and the pozzolanic effect induced by ash reduced plant growth significantly.     

Impact of Coal Ash from Electric Power Production on Changes in Water Quality1

ABSTRACT: Since 1972 the use of coal in the U.S. has increased much more rapidly than predicted, with much of this increased use by electric power generating plants. Residue after combustion consists primarily of inorganic materials, with the majority of chemical elements concentrated in fly ash as is sulfate. The concentration of sulfate in this ash fraction most affects the chemical and physical state of other elements when fly ash comes in contact with water by lowering the pH. In a properly constructed and operated ash settling basin, however, major water quality parameters of effluent may be improved as compared to source water. It is necessary, however, to consider the solubility or deposition in sediment of potentially toxic chemical elements from fly ash as these may affect reuse of this water, or as they may impact other parts of the aquatic environment.     

Effects of Lime and Ash Treatments on DOC Fractions and Low Molecular Weight Organic Acids in Soil Solutions of Acidified Podzolic Soils

Dissolved organic carbon (DOC) fractions and different low molecular weight organic acids (LMWOAs) were determined in soil solutions from two lime or ash treated Norway spruce sites in the south of Sweden. At Hasslöv, 3.45 t ha^-1 or 8.75 t ha^-1 dolomite were applied 15 years before sampling. Horröd was treated with 4.28 t ha^-1 ash and 3.25 t ha^-1 dolomite and sampled four years later. Propionate (7–268 M) and malonate (2–34 M) were the LMWOAsfound in the highest concentrations at Hasslöv. Two other LMWOAs dominated at Horröd, namely citrate (18–64 M)and fumarate (5–31 M). The differences in concentration of most of the determined LMWOAs at Hasslöv were significantly increased due to treatment. The LMWOAs comprised between 1.1–6.3% of the DOC at Hasslöv and 4.5–17.6% at Horröd. At Hasslöv normally 3–10% of the total acidity (TA) was due to LMWOAs and the average specific buffer capacity was 74 ± 22 mmol mol^-1C.The total DOC concentration in the mor layer solution was 16 mM for the dolomite treated plots compared to 10 mM at the untreated plot. A major part of the increase in DOC at the treated plots apparently had a hydrophobic character and was of high molecular weight corresponding to 3–10 kDa. The concentration of DOC < 1 kDa in the control and treated plots was similar.     

A Comparative Analysis of the Vegetation and Topsoil Cover Nutrient Status between Two Similarly Rehabilitated Ash Disposal Sites

The aim of this paper is to compare the rehabilitation result between two ash disposal sites with regard to its vegetation establishment and soil nutrient status. The study areas were situated in close proximity, in the Mpumalanga coalfield, South Africa. Although both areas received a similar amelioration treatment and were seeded with similar seed mixture the vegetation composition were significantly different. Both areas were poor in essential nutrients, this probably being one of the most limiting factors for vegetation establishment. No serious phytotoxic conditions, as is frequently experience with coal ash, could be identified. A regular monitoring and low level maintenance program is therefore proposed to improve the sustainability of the vegetation. The study proposed that results form such evaluations be used to identify performance standards for rehabilitated derelict land.