冶金技术在垃圾焚烧飞灰处理中的应用

垃圾焚烧飞灰因含有二恶英、重金属等毒害物,被确定为危险废物,是环境领域有待解决的难题。笔者研究了冶金领域成熟的技术和装备处理焚烧飞灰的潜力。文章介绍了火法冶金及湿法冶金中4种工艺及设备处理焚烧飞灰的新技术,即利用电弧炉熔融处理垃圾焚烧飞灰及熔渣制备微晶玻璃技术、利用铁浴熔融/冶金烧结处理焚烧飞灰及重金属分离技术、利用浮选法分离焚烧飞灰中二恶英和重金属技术、微波烧结处理焚烧飞灰的技术。分析了这些方法目前的在处理焚烧飞灰方面的研究进展以及应用前景,并提出了实际应用推广的建议     

烧结过程中二恶英的排放和生成机理研究进展

利用"辨别和量化二恶英及呋喃排放标准工具包"估算出2005年我国钢铁行业排放的二恶英总量达到1847.26 g TEQ.对当前已经开展的有关烧结过程中二恶英的分布和排放规律的研究进展进行了综述.提出了典型烧结烟气中二恶英同系物的分布规律,并以焚烧过程中二恶英的生成机理为基础讨论了烧结过程中二恶英的生成机理.目前的研究表明:烧结过程中二恶英的生成机理是"从头合成"、"前驱物合成"、"原生二恶英物质未完全分解"这三种生成机理综合作用的结果.     

垃圾热处理新技术--斯托克焚烧技术

对垃圾热处理技术的分类和各种方法进行了综述,详细介绍了一种新的垃圾焚烧技术--斯托克焚烧技术,以及利用斯托克装置进行发电和处理二恶英等有害排放物的新方法,最后提出了垃圾热处理的发展方向.     

我国再生铝工业中的二恶英问题

大力发展再生铝工业,已成为我国铝工业可持续发展的必然选择.但再生铝工业并非业界想象中的"绿色产业",其生产过程中排放的大量肉眼不可见的二恶英及其它有毒有害有机废气尚未得到治理,已经造成了不同程度的严重污染,而业界对此仍缺乏足够的认识.介绍了二恶英的性质、生成机理,参照其它焚烧型工艺的研究成果,对再生铝工业中二恶英的产生及其减排等进行了有益的探讨.     

我国再生铅工业中的二恶英问题

大力发展再生铝工业,已成为我国铝工业可持续发展的必然选择。但再生铝工业并非业界想象中的“绿色产业”,其生产过程中排放的大量肉眼不可见的二恶英及其它有毒有害有机废气尚未得到治理,已经造成了不同程度的严重污染,而业界对此仍缺乏足够的认识。介绍了二恶英的性质、生成机理,参照其它焚烧型工艺的研究成果,对再生铝工业中二恶英的产生及其减排等进行了有益的探讨。     

烧结烟气与垃圾焚烧控制二恶英的技术对比

钢铁企业中烧结烟气与垃圾焚烧是二恶英最主要的排放源。对比了烧结过程与垃圾焚烧中二恶英的生成机制;分别从添加抑制剂、优化工艺及烟气处理三个方面对两者的二恶英控制技术进行了论述和对比, 提出彻底解决二恶英污染问题需要在烟气排放过程中实现,建议烧结烟气控制二恶英借鉴垃圾焚烧SCR技术,垃圾焚烧控制二恶英采用烧结烟气的移动床活性炭脱硫技术。     

对我国建立垃圾发电厂及管理的建议

根据我国地少人多和城市垃圾产量增多的实际情况,借鉴了国内外城市垃圾的处理方法和焚烧发电的经验,提出了对我国建立垃圾发电厂及管理的建议。建议主要有加强垃圾的分类和管理、综合谨慎地进行垃圾发电厂的选址、提高垃圾发电设备的国产化水平、加强宣传,科学认识二恶英类污染、采取有效措施．控制二恶英类污染。     

电炉烟气二恶英减排技术现状及发展趋势

介绍了二恶英的生成机理及电炉烟气二恶英生成途径,重点介绍了电炉烟气二恶英减排技术、生成现状及减排技术进展,并比较分析了各种减排技术的优缺点,最后提出了基于高效过滤和余热回收的电炉烟气二恶英减排技术。     

水泥窑炉协同处理城市垃圾研究进展

水泥窑炉处理危险废物和城市生活垃圾是众多处理方法中实现减量化、无害化和资源化最好的方法之一。水泥窑焚烧垃圾可以利用垃圾的热量节省燃料,同时垃圾燃烧后的灰渣可以替代原料。另外,CaO和过渡性熟料矿物对有害物质的不良作用有抑制作用,也可以减少二恶英等有害气体的排放。     

烧结烟气减排二恶英技术的研究

作为钢铁冶炼的重要工序之一的烧结,其造成的二恶英污染问题已引起广泛重视.介绍了二恶英在烧结过程中的生成机理;根据其生成机理和烧结烟气的排放特性,对现有的几种烧结烟气减排二恶英的技术及其在工艺中的应用进行了深入的分析;提出了适合宝钢生产工艺特点的二恶英减排技术设想和建议.     

Levels of PCDDs and PCDFs in farm cow's milk located near potential contaminant sources in Asturias (Spain). Comparison with levels found in control, rural farms and commercial pasteurized cow's milks

Cows milk samples from 12 dairy farms in Spain and 23 samples of pasteurised cows milk were analysed for PCDD/F. Farms located in rural areas without specific dioxin sources (background levels) ranged from 1.3 to 2.47 pg TEQ/g fat basis. These values were slightly lower than those found in milk from the vicinity of potential dioxin emission sources (waste incinerator, chemical and metallurgical industry) and similar to milk near paper industry. The waste incinerator seems to be the emission source with the highest influence on the cows milk gathered in its vicinity. Thus, milk near the waste incinerator exhibited the highest PCDD/F levels, the highest PCDF/PCDD ratio and its congener PCDD pattern showed the highest difference respect to its control point. The PCDD/F average concentrations found in pasteurised commercial milk were lower than those found in raw milk and were comparable to those found in retail milk from other countries.     

Relationships between dioxins in soil, air, ash, and emissions from a municipal solid waste incinerator emitting large amounts of dioxins

The Columbus Municipal Waste-to-Energy (Columbus WTE) facility in Columbus, Ohio, began operation in June, 1983 and ceased operation in December, 1994. During its operation, it was estimated to have released nearly 1,000 grams of dioxin Toxic Equivalents (TEQs) per year. This compares to a 1994 estimate of 9,300 g TEQ/yr from all sources emitting dioxins into the air in the United States (EPA, 1994), and to total releases of dioxins near or below 1,000 grams TEQ/Yr for England (Eduljee and Keyke, 1996), Belgium (Wevers and De Fre, 1995), and West Germany (Fiedler and Hutzinger, 1992). Because of the magnitude of emissions from this single source, studies were undertaken to evaluate the impacts to air and soil near the incinerator. This paper presents analyses evaluating dioxin concentrations and profiles in four media: stack gas, ambient air within 3 km of the incinerator, soil samples up to 8 km from the incinerator, and incinerator ash. Principal findings include: 1) an "incinerator signature" profile, as defined by stack gas emissions, was found in the ash and in subsets of the air and soil matrices, 2) soil concentrations declined from directly outside the incinerator property to the city at large, 3) an urban background soil concentration of dioxin Toxic Equivalents (TEQs) was estimated at 4 pg/g, while concentrations generally within 2 km of the incinerator ranged from 4-60 pg TEQ/g, 4) an urban background air concentration was estimated at 0.05 pg TEQ/m3, while air concentrations at a specific location about 2 km in the downwind direction of the incinerator had concentrations of 0.17 and 0.35 pg TEQ/m3 during two sampling dates, 5) analysis of the soil monitoring data in combination with the stack test data suggests that less than 2% of emitted dioxins can be found in the soil near the incinerator, and 6) principal component analysis suggests that the fraction of total concentration of OCDD is the single feature explaining most of the variation of all concentration profiles. This paper discusses these and other findings, and their implications.     

垃圾焚烧炉用耐火材料的研究现状

介绍了目前国外垃圾焚烧炉的种类和特点,较系统地阐述了目前垃圾焚烧炉用耐火材料的研究现状。重点介绍了无铬耐火材料的研究现状并指出了焚烧炉用耐火材料今后的发展方向．     

危险废物回转窑焚烧炉的工艺设计

结合工程的实际经验数据,给出了在确定危险废物回转窑焚烧炉的主要参数设计时应注意的问题。     

危险废物回转窑焚烧炉的工艺设计

结合工程的实际经验数据，给出了在确定危险废物回转窑焚烧炉的主要参数设计时应注意的问题。     

Analysis of polychlorinated dibenzofurans (PCDFs) in fly ash from a waste incineration plant

In this study, a method for the congener-specific analysis of polychlorinated dibenzofurans (PCDFs) in fly ash from a waste incineration plant is described. This method involves extraction, column chromatography, and gas chromatographic-mass spectrometric techniques. Representative fly ash samples are obtained from the waste incinerator. The purpose of this research is to briefly present the findings as they relate to PCDFs. Analyses indicate that PCDFs are consistently found in the municipal incinerator.     

Simulation of Municipal Solid Waste Incinerator Ash/Cement Systems by Means of Factorial Experiments

In the present paper, the behavior of municipal solid waste incinerator ash in cement-based systems was simulated by spiking experiments on portland cement making use of pure compounds, including MgCl2, K2SO4, Zn(NO3)2, and NaNO2, which were selected based on the findings from previous investigation. A 24?1 fractional factorial design was used to arrange the program of experiments. The evolution of physical and mechanical properties as well as acid neutralization capacity with curing time was studied with the aid of statistical analysis. Based on the results from the present work, a model was developed for prediction of unconfined compressive strength and buffering capacity of incinerator ash?portland cement mixtures. The good agreement between predicted and measured values indicated that the behavior of incinerator ash in cementitious systems is largely to be ascribed to the four selected compounds.     

An investigation of environmental levels of cadmium and lead in airborne matter and surface soils within the locality of a municipal waste incinerator

The results of an investigation into the environmental impact of heavy metals in the airborne emissions from the Baldovie municipal waste incinerator, Scotland, are presented. A sampling network of 1-km grid squares covering a 7 x 9 km area was established over the incinerator plant and its surroundings. Surface soil core samples were collected from within each 1 km2 and analysed for cadmium and lead content. The spatial distribution of lead levels in soils showed a marked variation downwind from the Baldovie incinerator in comparison with the background level for the area but remained well within the typical range of lead in rural, unpolluted, British soils. A comparison of the observed levels of lead in local soils, with the predicted downwind long-term ground level lead distribution in air indicates that atmospheric emissions of lead originating from the Baldovie incinerator directly determine concentrations of lead in soils within a radius of 5 km of the incinerator. An empirical relationship between the levels of lead in soils and the long-term levels in air was established. In the case of cadmium, the spatial distribution of the heavy metal showed neither a marked nor extensive contamination of the sampled area around the incinerator and remained within the typical range of cadmium levels in rural, unpolluted, British soils. The work concludes that atmospheric emissions of lead from the Baldovie incinerator significantly determines the local distribution of lead in soils within the immediate vicinity of the incinerator.     

废弃物与焚烧设备数据库及其知识发现

文章简要介绍了废弃物与焚烧设备数据库及其管理系统的内容、特点、以及KDD技术.讨论了该数据库中知识发现的可能性和应用价值.