Characterization of chlorine and heavy metals for the potential recycling of bottom ash from municipal solid waste incinerators as cement additives

Bottom ash is an inevitable by-product from municipal solid waste (MSW) incineration plants. Recycling it as additives for cement production is a promising disposal method. However, the heavy metals and chlorine are the main limiting factors because of the potential environmental risks and corrosion of cement kilns. Therefore, investigating heavy metal and chlorine characteristics of bottom ash is the significant prerequisite of its reuse in cement industries. In this study, a correlative analysis was conducted to evaluate the effect of the MSW components and collection mode on the heavy metal and chlorine characteristics in bottom ash. The chemical speciation of insoluble chlorine was also investigated by synchrotron X-ray diffraction analysis. The results showed that industrial waste was the main source of heavy metals, especially Cr and Pb, in bottom ash. The higher contents of plastics and kitchen waste lead to the higher chlorine level (0.6 wt.%–0.7 wt.%) of the bottom ash. The insoluble chlorine in the MSW incineration bottom ash existed primarily as AlOCl, which was produced under the high temperature (1250°C) in incinerators.

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岸坡侵蚀及其防治

岸坡侵蚀是土地侵蚀的一个类型．它进一步又可划分为岸坡崩塌、滑坡侵蚀，岸坡塌陷侵蚀，岸坡沟谷侵蚀和岸坡洪水侵蚀。本文在详细分析各类岸坡侵蚀的基础上，提出了岸坡侵蚀的特点和防治对策。     

挥发性有机物废气的膜法处理工艺研究进展

简要介绍了挥发性有机物废气的来源，分类及其对人体和环境的危害，以及国内外近年来的排放状况。较详细地论述了蒸汽渗透，气体膜分离，膜基吸收3种膜技术用于废气中挥发性有机化合物去除和回收的研究进展和工业应用现状。     

维护生态环境 促进经济发展

本文阐述了生态环境与社会经济之间的关系，探讨了保护环境、资源对发展经济的作用。     

浅析石化企业硫化氢应急防范工作中的误区

近年来,随着高含硫原油加工量的增多,石油化工企业硫化氢中毒事故频发,引起了整个行业的高度重视。针对硫化氢的应急防范,各企业不断加大投入,配置报警仪、防护器具,细化应急预案和管理规定。但在实施过程中也产生了许多误区,本文对几个带有普遍性的问题逐一分析,并提出整改建议。     

微波改性高炉瓦斯泥吸附特性研究

以马鞍山钢铁公司高炉瓦斯泥为对象,采用微波改性方法对高炉瓦斯泥的粒度分布、微观形貌及化学变化进行表征分析,揭示了微波作用对瓦斯泥吸附特性的影响.结果表明,高炉瓦斯泥的主要组分为含铁烧结矿和焦炭颗粒,经微波改性的瓦斯泥颗粒,在形貌上显示出粗糙度增大,孔隙结构明显,比表面积增大和活性点增多的特征.通过对亚甲基蓝的吸附测试,...     

Composition and crystal structure of N doped TiO2 film deposited at different O2 flow rate by direct current sputtering

N doped Ti0₂ films were deposited by direct current pulse magnetron sputtering system at room temperature. The influence of 0₂ flow rate on the crystal structure of deposited films was studied by Stylus profilometer, X-ray photoelectron spectroscopy, and X-ray diffractometer. The results indicate that the 0₂ flow rate strongly controls the growth behavior and crystal structure of N doped Ti0₂ film. It is found that N element mainly exists as substitutional doped state and the chemical stiochiometry is near to TiO_1.68±0.06N_0.11±0.01 for all film samples. N doped Ti0₂ film deposited with 2 sccm (standard-state cubic centimeter per minute) 0₂ flow rate is amorphous structure with high growth rate, which contains both anatase phase and rutile phase crystal nucleuses. In this case, the film displays the mix-phase of anatase and rutile after annealing treatment. While N doped Ti0₂ film deposited with 12 cm³/min 0₂ flow rate displays anatase phase before and after annealing treatment. And it should be noticed that no TiN phase appears for all samples before and after annealing treatment.     

Greenhouse gas emission and its potential mitigation process from the waste sector in a large-scale exhibition

As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO₂-equivalent (CO₂-eq.), 4.43 kg SO₂-eq., 4.88 kg NO₃⁻-eq., and 3509 m³ water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO₂-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO₂-eq., and CH₄, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO₂-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.     

The Second Sino-FrenchWorkshop on Atmospheric Environment (Orleans, December 2010): Preface

A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world's economic and societal activities.Many environmental issues,such as air quality and climate change are intimately linked to atmospheric chemistry and physics,therefore research in these areas is of tremendous importance.Both anthropogenic and biogenic emissions contribute greatly to the chemical composition of the atmosphere.Even though the atmosphere is a self-cleaning system through its photochemically-driven reactions,the hazardous direct impacts of primary and secondary pollutants on human health and ecosystems are observable and have been evidenced on different scales from local to global (e.g.ozone hole,climate change,air quality…).The chemical processing of the species present in the atmosphere is one of the most important players in driving the evolution of the atmosphere.     

高温厌氧消化污泥的培养试验研究

在试验室半连续装置中培养高温厌氧消化污泥,以中温厌氧污泥作为种泥,中温启动运行一段时间后,再逐步升温,经过100d运行可达到高温厌氧消化运行的良好状态。整个试验过程中无需人为调节碱度,pH值比较稳定。45℃以下,升温对厌氧消化系统的扰动比较小,之后继续升温至48℃,厌氧消化系统不稳定。认为45～48℃可能存在着中温和高温厌氧消化的临界温度,在这一温度下,中温细菌可能会大量死亡,但是不适合高温菌生长或对应着较低的生长速率。