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741.
742.
城市垃圾焚烧中PVC环境影响研究 总被引:1,自引:0,他引:1
在城市生活垃圾中,大约有一半的氯来自PVC废物。在垃圾焚烧过程中,PVC含量的增加可导致HCl产生量的增加,并有可能成为二噁Ying生成的氯源。PVC中铅含量最高,但对生活垃圾相对贡献量不大。PVC对生活垃圾的镉相对贡献量最大,而且在含PVC垃圾焚烧过程中烟气中镉的浓度也有明显增加。此外,PVC有使重金属从底灰向飞灰转移的趋势,这对于后续的底灰处置是有利的。在分析PVC对城市垃圾焚烧过程影响的基础上,本文最后提出了结论和建议。 相似文献
743.
建立了土壤和小麦种子、茎杆中苯达嗪丙酯的残留分析方法.研究了高剂量施药条件下土壤中的消解动态,并测定了土壤、小麦种子和茎杆中的最终残留.苯达嗪丙酯的最低检出限为10ng,在土壤和小麦中的最低检出浓度为0.05mg·kg-1.方法的平均添加回收率为88.7%—103.3%,变异系数为4.3%—16.4%.苯达嗪丙酯的消解动态试验表明:高剂量施药条件下苯达嗪丙酯在土壤中的半衰期分别为2.5d(北京)和3.1d(石家庄);当按推荐剂量施药时,小麦收获前10d,在土壤、小麦种子和茎杆中,北京和石家庄两地均未检出苯达嗪丙酯. 相似文献
744.
针对城市生活垃圾焚烧(MSWI)过程中二(口恶)英类的生成机制以及焚烧飞灰的组成,研究了MSWI飞灰中常见的钙化合物(CaO,Ca(OH)2,CaCl2,CaSO4及Ca(NO3)2)对前生体五氯酚(PCP)及六氯苯(HCB)生成二(口恶)英类的阻滞作用.结果表明,280℃下加热2 h,Ca(NO3)2,Ca(OH)2和CaO对PCP生成二(口恶)英类的总阻滞效率分别为93.7%,80.4%和98.9%,而CaCl2和CaSO4几乎没有效果.CaO对PCP和HCB混合物生成二(口恶)英类物质同样具有良好的阻滞效果.另外,探讨了上述钙化合物对PCP及HCB生成二(口恶)英类的阻滞作用机理. 相似文献
745.
吐氏酸废液资源化技术的研究 总被引:6,自引:1,他引:5
研究了用化学萃取法回收吐氏酸废母液中染料中间体的多种影响因素,静态试验表明:通过萃取工艺,吐氏酸废母液中的染料中间体回收率可达90%以上,萃余液中CODcr在500~3000mg/L之间;该工艺可使废母液中的回收物浓缩5~10倍,根据静态试验得出的工艺参数,进行了动态模拟试验,取得了与静态试验非常接近的结果,为以后的示范工程提供了可靠的设计依据。 相似文献
746.
Vincent T. Breslin 《Journal of Polymers and the Environment》1998,6(1):9-21
The compostability of starch–CaCO3 disposable packaging was examined in a source-separated municipal solid waste (MSW) composting facility located in East Hampton, NY. Source-separated MSW:starch–CaCO3 container mixtures of 0 (control), 5, and 20% (by volume) were prepared as feedstock for composting. Compost samples were collected weekly or biweekly during the composting process and examined for fragments of the starch–CaCO3 containers. Changes in compost quality due to the presence of starch–CaCO3 containers were assessed by measuring the nutrient and metal content of the three resultant MSW:starch–CaCO3 composts. Finally, plant growth studies were conducted to examine the composts for possible plant growth inhibition due to the deterioration of the starch–CaCO3 containers. Results showed that portions of the starch–CaCO3 containers were not identified in any of the 5 and 20% sieved and characterized compost fractions > 1.3 cm following 1–3 weeks of composting. Mechanical agitation of the waste along with optimum composting conditions were sufficient to initiate the rapid degradation of the starch–CaCO3 composites. Degradation of starch–CaCO3 containers did not affect compost nutrient and trace element content. Grass biomass measurements were performed once weekly over 28 days for grass grown in control (0%), 5%, and 20% starch–CaCO3-containing compost:soil mixtures. Significant differences in grass biomass for these compost:soil mixtures were measured only for the 0 and 20% starch–CaCO3-containing compost:soil mixtures at 28 days (9.07 vs 11.05 g, respectively; P = 0.046). 相似文献
747.
States differ in the components or solid waste management activities which they include when determining solid waste reduction and recycling rates. Thus, when attempting to draw comparisons among states, confusion arises in two ways: (1) use of two types of rates; and (2) use of different components or activities when calculating a given rate. This paper presents a mathematical basis for understanding the impacts on rate calculations when variations occur in the components and activities included in those calculations. Estimates of the incremental changes occurring in the rate calculations when incineration or selected components such as yard waste, construction and demolition wastes, and junked automobiles, are added to a base of municipal solid waste constituents are found using national data. Finally, the achieved rates reported by states counting different combinations are compared. 相似文献
748.
/ A methodology to estimate the number of pump-out facilities and dump stations required to service human waste disposal for recreational power boating activities in Pennsylvania during the 1994 boating season is described. Study results suggest that a total of 39 additional pump-out stations and 13 dump stations may be required on seven major waterbodies: The Three Rivers Area, Lake Erie/Presque Isle Bay, Raystown Lake, the Susquehanna River, the Delaware River, Lake Wallenpaupack, and the Kinzua Reservoir. Suggestions for improving the methodology are provided. KEY WORDS: Human waste; Recreation; Power boating; Waste facilities; Waste disposal; Pennsylvania 相似文献
749.
Without public contributions, recycling from domestic waste would not be possible. In order to support recycling projects it is important to try to understand who recycles, how they recycle, and why they recycle. This paper presents the results of a structured survey of 500 members of the public served by schemes to collect plastics waste for recycling. Data were gathered on the characteristics, behaviours and motivations of recyclers. The authors also sought to discover how the public perceive plastics compared to other materials, and as a recyclable material. Responses were collected in such a way that the awareness of the recyclability of materials could be compared with the recycling behaviour of respondents. An element of comparison was introduced between those served by a system of bottle banks (bring scheme) and those covered by a household collection (collect scheme). The survey results are reported and their implications for the management of post-consumer plastics waste collection schemes are discussed. 相似文献
750.
化工废水中含有机物、烃类、石油类、重金属等有毒有害物质,成分复杂,难于生物降解,并且对微生物代谢产生抑制和毒害作用.文章通过研究石化废水二级生化处理后回用的工艺技术,提出以絮凝、氧化、膜分离等组合工艺为主体的石化废水深度处理流程,并对设计参数、工艺调试进行优化分析,为石化废水处理回用开辟途径. 相似文献