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751.
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
752.
燃煤灰渣建材利用是解决粉煤灰问题的一个重要途径,而燃煤灰渣对煤中伴生的天然放射性物质的富集使得在对粉煤灰渣进行建材利用时要特别注意其放射性对人类和环境产生的辐射影响。本文依据国家相关标准对燃煤灰渣建材利用产生的辐射影响评价方法作一些探讨,并参考现有的数据对燃煤灰渣建材利用的辐射影响进行了初步评价。研究认为,以现有的灰渣建材利用水平,其产生的辐射影响几乎可以忽略。 相似文献
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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
758.
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
759.
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
760.
《International Journal of Sustainable Engineering》2013,6(3):211-218
Alkali ash material (AAM) concrete is a unique material that is sustainable and cost-effective because it utilises waste fly ash, and has properties superior to other concrete products. The AAM concrete described here is produced from the addition of inexpensive chemicals to fly ash. AAM can be used to create a wide range of materials including high performance concrete (HPC-AAM) and lightweight (LW-AAM). The high performance AAM provides rapid strength gain along with high ultimate strengths of more than 110 MPa (16000 psi). LW-AAM can produce materials with densities ranging from 1200 to 2200 kg/m3 and compressive strengths from 2 (290 psi) to 65 MPa (9500 psi). Both HPC-AAM and LW-AAM have far better environmental resistance than Portland cement concrete, resisting attack from sulphuric acid (H2SO4), hydrochloric acid (HCl) and organic acids. AAMs resists freeze–thaw attack and high abrasion, possesses low chloride permeability and does not exhibit alkali silica reactivity. 相似文献