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751.
详细介绍了山西焦化股份有限公司针对锅炉除尘系统运行中存在的问题进行的多项技术改造,改造后其除尘效率得以提高,烟尘排放质量浓度达到国家一级标准。 相似文献
752.
以粉煤灰的特殊结构为基础 ,分析了石灰 粉煤灰水合反应制备高活性脱硫剂的反应产物、反应过程 ,以及添加剂和压力水合的机制 相似文献
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754.
A new iron-fly ash packing was studied for reductive transformation of p-nitrotoluene. The packing was made of iron, fly ash and kaolin with the mass ratio of 36:7:2. A reactor was designed to investigate the long-term performance of the packing. The results showed that the reduction of p-nitrotoluene increased with decreasing pH, because the reduction potential of reaction increased with the concentration of H+. The pH was one of the key factors impacting the reductive transformation of p-nitrotoluene. Comparing iron-activated carbon packing with the new iron-fly ash packing, the reduction efficiencies were respectively 76.61% and 75.36% after 20 days. The reduction efficiency for both was around 50% at 40 days. It was evident that these two kinds of packing had no significant difference in their capability for p-nitrotoluene reductive transformation. Compared with iron-activated carbon, the new iron-fly ash packing had obvious advantages in terms of manufacturing costs and environmental pollution degradation. This study showed that the new iron-fly ash packing had good performance in reductive transformation of nitrotoluene compounds. 相似文献
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756.
不同粒径垃圾焚烧飞灰重金属毒性浸出及生物可给性 总被引:7,自引:5,他引:2
对城市生活垃圾焚烧飞灰的化学性质和粒径分级毒性进行分析研究,并采用美国EPA的毒性浸出程序TCLP(toxicity characteristic leaching procedure)、欧盟危险废物鉴别浸出标准(EN12457-2)、逐级浸出程序SEP(sequential extraction procedure)与体外模拟实验方法 PBET(physiologically based extraction test)对不同粒径的焚烧飞灰中重金属浸出效果进行对比研究.结果表明,焚烧飞灰的主要组成元素为Ca、Si、Al、Mg、Fe、Na和K;58.7%的飞灰粒径分布在38~106μm,粒径小于150μm的焚烧飞灰占总量的90%以上.重金属Cu、Pb和Cd等在各粒径飞灰中主要以残渣态的形式存在,可交换态较少.TCLP结果证实,除As和V外,Zn、Cu和Pb的浸出量随飞灰粒径的减小呈先增大后减少的趋势,粒径在38~106μm下Zn的浸出量最大为547 mg·kg~(-1),而采用欧盟浸出标准,所有粒径飞灰的重金属浸出量都较低.PBET实验中Zn、Pb、Cu和As的浸取浓度分别达3 270、339、335和16.8 mg·kg~(-1),其结果显著高于TCLP重金属浸出量,说明焚烧飞灰中重金属对于人体具有潜在的生物有效性. 相似文献
757.
Natalya Irha 《毒物与环境化学》2013,95(1-2):105-110
The aim of this work was to estimate the sorption of pyrene from water solutions on mineral substrates, e.g., alumina, silica, and oil shale ash, from the Estonian thermal plant. Results obtained from this study indicate that the sorption of pyrene on mineral oxides and oil shale ash particles from water can be described with a linear equation. The sorptive capacity per weight of oil shale ash in aqueous systems was significantly lower compared with mineral adsorbents. The distribution coefficient (Kd) for pyrene in the system with particles of oil shale ash was 10–12 times lower as than for mineral adsorbents. 相似文献
758.
Coal fly ash (CFA) is dumped at a deep sea disposal site (1,500m water depth) in the eastern Mediterranean, ca. 70km off the Israeli shore. Since 1989, about one million tons of CFA were dumped at the 200km2 allocated area. Six years of monitoring at the dump-site shows that the CFA is heterogeneously distributed; there are areas where CFA covers about 1.3cm depth of the sea floor while at others no CFA is found. CFA is present as a fine powder, small aggregates and even as large blocks both in the dump-site as well as at its peripheries. Cadmium, copper and zinc concentrations in the CFA decreased as a result of the prolonged contact with sea water at in situ conditions while inconclusive changes in mercury, iron and manganese were detected. No changes were observed for lead, iron and aluminium concentrations. A controlled long term field experiment, now in progress at the site, is expected to clarify further chemical changes occurring in the CFA. 相似文献
759.
760.
T. A. Pristova 《Russian Journal of Ecology》2008,39(3):176-182
The biological turnover of nitrogen and ash elements has been studied in a secondary deciduous-coniferous stand formed in place of a clear-cut spruce forest. The results have shown that a high degree of accumulation is characteristic of Ca, N, K, and Si, with N, Ca, K, Si, P, and Mg being most actively involved in the biological turnover. The biological turnover in this stand is of the calcium-nitrogen-potassium type, and its intensity and rate exceed those in bilberry spruce forest by factors of 1.7 and 2–4, respectively. 相似文献