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11.
简要介绍了等离子体的相关概念及其处理污染物的工作原理,阐述了等离子体技术在固体废弃物治理方面的应用研究概况,并对等离子体在固体废弃物治理中的应用作了市场前景分析,说明了该技术在固体废弃物治理中具有一定的应用前景。 相似文献
12.
Occurence and Distribution of Polycyclic Aromatic Hydrocarbons in Ankara Precipitation 总被引:1,自引:0,他引:1
Urban atmospheric environment contains many trace organic pollutants that are related to the incomplete fuel combustion in domestic heating, industrial plants and automobile traffic. Removal of these pollutants from the atmosphere takes place through wet and dry deposition as well as chemical transformations. In this study, concentrations of polycyclic aromatic hydrocarbons (PAHs) in wet deposition samples were determined at an urban site of Turkey. Wet and dry deposition samples were collected using Andersen Rain Sampler. The sampler was modified accordingly for the collection of organic pollutants. Collected samples were preconcentrated by using solid phase extraction (SPE) disks and consecutively analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Among the 13 compounds quantified in this study, anthracene, fluoranthene, and pyrene were found more frequently and at elevated concentrations (202, 271 and 260 ng L-1 mean concentrations, respectively).Concentrations of PAHs were found to be high in winter period. 相似文献
13.
H. Ozaki K. Sharma C. Phanuwan K. Fukushi C. Polprasert 《Journal of Material Cycles and Waste Management》2003,5(1):0031-0038
This paper deals with the present scenario of hazardous waste management practices in Thailand, and gives some insights into
future prospects. Industrialization in Thailand has systematically increased the generation of hazardous waste. The total
hazardous waste generated in 2001 was 1.65 million tons. It is estimated that over 300 million kg/year of hazardous waste
is generated from nonindustrial, community sources (e.g., batteries, fluorescent lamps, cleansing chemicals, pesticides).
No special facilities are available for handling these wastes. There are neither well-established systems for separation,
storage, collection, and transportation, nor the effective enforcement of regulations related to hazardous wastes management
generated from industrial or nonindustrial sectors. Therefore, because of a lack of treatment and disposal facilities, these
wastes find their way into municipal wastewaters, public landfills, nearby dump sites, or waterways, raising serious environmental
concern. Furthermore, Thailand does not have an integrated regulatory framework regarding the monitoring and management of
hazardous materials and wastes. In addition to the absence of a national definition of hazardous wastes, limited funding has
caused significant impediments to the effective management of hazardous waste. Thus, current waste management practices in
Thailand present significant potential hazards to humans and the environment. The challenging issues of hazardous waste management
in Thailand are not only related to a scarcity of financial resources (required for treatment and disposal facilities), but
also to the fact that there has been no development of appropriate technology following the principles of waste minimization
and sustainable development. A holistic approach to achieving effective hazardous waste management that integrates the efforts
of all sectors, government, private, and community, is needed for the betterment of human health and the environment.
Received: February 26, 2001 / Accepted: October 11, 2002 相似文献
14.
15.
从废感光胶片中回收银 总被引:2,自引:0,他引:2
研究了以Fe3 -乙二胺四乙酸二钠-N a2S2O3体系为浸取剂从废感光胶片中回收银的方法,考察了浸出银的最佳工艺条件。实验表明,当浸取剂中FeC l3.6H2O质量浓度为35g/L、N a2S2O3.5H2O质量浓度为150g/L、pH为7、固液质量比为3∶10时,浸取剂可重复使用6次,胶片上银的浸出率可达99%以上;浸取液中的银采用硼氢化钠还原回收,粗银粉配以熔剂高温熔炼可得到纯度达99.78%的银,银回收率达96.88%,回收银后的浸取液可循环使用。 相似文献
16.
17.
Jonn A. Foulk Wayne Y. Chao Danny E. Akin Roy B. Dodd Patricia A. Layton 《Journal of Polymers and the Environment》2004,12(3):165-171
Municipal solid wastes generated each year contain potentially useful and recyclable materials for composites. Simultaneously, interest is high for the use of natural fibers, such as flax (Linum usitatissimum L.), in composites thus providing cost and environmental benefits. To investigate the utility of these materials, composites containing flax fibers with recycled high density polyethylene (HDPE) were created and compared with similar products made with wood pulp, glass, and carbon fibers. Flax was either enzyme- or dew-retted to observe composite property differences between diverse levels of enzyme formulations and retting techniques. Coupling agents would strengthen binding between fibers and HDPE but in this study fibers were not modified in anyway to observe mechanical property differences between natural fiber composites. Composites with flax fibers from various retting methods, i.e., dew- vs. enzyme-retting, behaved differently; dew-retted fiber composites resulted in both lower strength and percent elongation. The lowest level of enzyme-retting and the most economical process produces composites that do not appear to differ from the highest level of enzyme-retting. Flax fibers improved the modulus of elasticity over wood pulp and HDPE alone and were less dense than glass or carbon fiber composites. Likely, differences in surface properties of the various flax fibers, while poorly defined and requiring further research, caused various interactions with the resin that influenced composite properties. 相似文献
18.
Idris Azni Saed Katayon Muniandy Ratnasamy Megat Mohd Noor Megat Johari 《Journal of Material Cycles and Waste Management》2005,7(1):33-37
This article reports the operational results of the effective utilization of hospital waste molten slag produced using a high-temperature melting system, and being operated at a hospital in Selangor, Malaysia. The hospital waste is incinerated and subsequently melted at 1200°C. Scanning election microscope (SEM)/EDX results showed that the slag produced after melting contained amounts of SiO2, CaO, and Al2O3 in excess of 53%, 9%, and 16%, respectively. The results from a leaching analysis on the slag produced proved that the melting process had successfully stabilized the heavy metals. The use of this slag as an alternative material to replace conventional aggregates for road construction was studied. The results from aggregate and asphalt mix tests showed that the slag produced fulfills all the requirements of an alternative aggregate. The average asphalt content, or the optimum asphalt content to be mixed with hospital waste molten slag, was found to be about 5.53%. 相似文献
19.
通过模拟煅烧试验制取水泥熟料,参照JGJ 55-2000(《普通混凝土配比设计规程》)制取混凝土样品,参考SR003.1和NEN 7375浸出试验,分别研究液固比对粒状及块状混凝土样品中重金属(Cr、Ni和As)释放的影响。结果表明,在不同液固比条件下粒状混凝土中的重金属浸出浓度为Cr>Ni>As,Cr、As浸出浓度基本保持不变,分别为2 500 μg/L左右和5~6 μg/L,Ni在液固比(L∶S)<6时,浸出浓度随着液固比的增加而降低,在L∶S>6时,浸出浓度较稳定,为35.7~41.5 μg/L;浸出量均随着液固比的增加而增大。液固比(L∶S)<10时,块状混凝土中重金属累积释放量及扩散系数均随液固比的增加而增大,当L∶S>10时两者基本保持不变。 相似文献
20.
黄土在世界上分布面积较广,在我国也有约60×104 km2的分布,具有湿陷性是其区别于其它区域性土的最显著特点,并由此引发造成各种地质灾害和工程问题.采用石灰、水泥或高分子材料等对其进行改性以达到消除湿陷性或提高黄土强度的目的,是岩土工程领域的重要课题.选用矿渣和工业废渣作为改性参料,用以研究改性黄土的力学特性变化和改... 相似文献