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61.
掺粉煤灰的橡塑复合材料研究和开发   总被引:2,自引:0,他引:2  
概述了粉煤灰再利用的必要性及掺有粉煤灰的橡塑复合材料的应用研究和开发概况,介绍了国内橡塑粉煤灰复合材料的研究及开发进展,综述了橡塑粉煤灰复合材料的应用。  相似文献   
62.
This paper presents results of an experimental program conducted to investigate the capacity of hydration products of different cementing materials to retain “bound” alkalis when the alkalinity of the surrounding solution drops. The study covered paste samples containing high-alkali Portland cement and various levels of silica fume and/or fly ash. The results showed that the ability of the hydration products of cement-fly ash systems to bind alkalis is a function of the CaO content of the fly ash, the binding increasing as the calcium content decreases. High-alkali fly ashes (Na2Oe > 5.0% and CaO in the range of 15% to 20%) showed considerable amounts of alkali contributed to the test solutions. Silica fume does not have a high capacity to retain alkalis in its hydration products; however, ternary blends containing silica fume and fly ash have excellent capacity to bind and retain alkalis.  相似文献   
63.
1,7-Dioxaspiro[5.5]undecane (olean), the major component of the female sex attractant pheromone blend of the olive fruit flyDacus oleae (Gmelin) was shown to be released as a racemate. The response of males and females to pure (R)-(–) and (S)-(+)-enantiomers was tested under laboratory and field conditions. Males in laboratory and field tests responded only to (R)-(–)-olean, which functions as a sex attractant. Females responded only to (S)-(+)-olean in laboratory tests but not in the field. There are indications that the latter enantiomer fuctions as a short-range arrestant throughout the day and as an aphrodisiac in the process of mating.Diptera: Tephritidae.  相似文献   
64.
陈英  谢文玉  陈建军 《广东化工》2006,33(10):54-56,51
初步分析了奥里油废水的水质,研究了用酸改性粉煤灰处理奥里油废水的工艺。奥里油废水是一种含有一定表面活性剂、高COD值(大于6000 mg/L)、难生物降解和难O3氧化降解的炼油废水。利用改酸性粉煤灰可对该废水进行预处理,COD去除率达45%。预处理工艺条件是,室温下灰水质量比15∶50,吸附搅拌时间30 min,pH为2~10。  相似文献   
65.
准东煤中钠含量高,燃用时锅炉会出现严重结渣问题。通过向准东煤为原料制取的超纯煤中添加灰的模型化合物,得到合成煤。并在此基础上利用热重-差示扫描量热分析法(TG/DTG/DSC)、X射线衍射仪(XRD)和灰熔融温度测定分析手段,研究Na2O含量对煤燃烧特性和灰熔融性的影响。结果表明:钠主要影响合成煤的着火温度(Ti)与焦炭燃烧阶段,钠含量增加使Ti升高,并且Na2O在灰中质量分数由5%升高至8%后,钠含量增加使焦炭燃烧速率先减小后加快,并能够改善煤粉燃尽特性。钠能够降低灰熔融温度,并在Na2O质量分数高于5%后,温度下降更加明显。在三元相图中钠对莫来石的助熔作用是造成灰熔融温度降低的重要原因。XRD分析表明Na2O含量增加,充当骨架作用的石英在钠的助熔作用下与难熔矿物硅钙石、MgO等生成低熔点长石类矿物,这类矿物在高温下有助熔作用,能够降低灰熔融温度。同时还生成助熔性含钠矿物霞石,加剧了灰熔融。  相似文献   
66.
Oxidation reactivity studies are imperative for improving carbon re-burn technologies and valuing the heat content of unburned carbon within coal combustion ashes. Non-isothermal, thermal gravimetric analysis (TGA) was used to examine the oxidation kinetics of unburned carbon in coal combustion fly ashes having different particle size distributions; TGA results were related to combustion efficiencies as measured in a bench-scale rotary kiln. The activation energy and pre-exponential factor were determined for the chemically-controlled reaction regime; the transition temperatures between chemically-controlled and partially diffusion-controlled combustion regimes were obtained for unburned carbon particles of different sizes. After the oxidation reaction rates were evaluated, the residence time distribution (RTD) of fly ashes in the rotary kiln were experimentally measured and the mean residence times related to process parameters, including the rotating velocity and kiln inclination. By comparing these results with an advective-dispersive model, the axial dispersion coefficient of fly ashes was determined. The reaction rates obtained by thermal analyses and the RTDs were used to predict combustion efficiencies within the kiln and oxidation conditions of unburned carbon using various processing options.  相似文献   
67.
热解气化过程中 ,促进焦油的裂解使之转化为高热值煤气 ,对高挥发分劣质煤和生物质燃料的清洁高效利用具有重要的意义 .在固定床反应器上 ,以石英砂和两种烟煤在循环流化床锅炉上燃烧形成的循环灰为床料 ,实验研究了焦油中含量较高的 1 -甲基萘的裂解反应 ,测定了反应动力学参数 .结果表明 ,与石英砂条件下相比 ,循环灰促进了 1 -甲基萘的裂解 ,反应活化能降低 ,裂解气体的总产率提高  相似文献   
68.
高掺量增钙粉煤灰水泥的研制   总被引:3,自引:0,他引:3  
本文研制的激活安定剂,能解决高掺量增钙粉煤灰水泥体积安定性不良的问题,提高该水泥的7天、28天强度,缩短凝结时间,使增钙灰掺量高达65%可以制备275砌筑水泥、掺42%的高钙粉煤灰的水泥达32.5级水泥。工业怀实验生产出65%增钙灰掺量的275砌筑水泥。  相似文献   
69.
The possibility of using fly ash from municipal solid waste incineration (MSWI) in, for example, concrete is considered. MSWI fly ash, however, has too high a concentration of heavy metals, which may cause leaching problems during use or problems with waste handling at the end of the lifetime of the concrete. The Cl content in MSWI fly ash is also too high and will cause corrosion problems in reinforced concrete. The possibility of removing some of the unwanted heavy metals (Cu and Pb) together with Cl from an MSWI fly ash suspended in water using an electrodialytic separation method was investigated. The removal of Pb and Cu was found to be highly pH dependent and the highest contents removed were 41 and 90%, respectively. The Cu concentration of the ash decreased from 2200 to 860 mg kg?1 but the Pb concentration increased from 8560 to 16 800 mg kg?1, showing that Pb is mainly found in the ash fraction that is least soluble. Hence electrodialytic treatment of the ash suspended in water is not a solution to improve the ash quality in terms of Pb. The water‐soluble Cl content per unit weight of the original ash was 12.4%. The removal of water‐soluble Cl was efficient and >98% of Cl was removed (calculated on the basis of mean initial and final concentrations). This result indicates that electrodialytic extraction may be a method that can be used for the removal of Cl from ash prior to its utilization in concrete. Copyright © 2006 Society of Chemical Industry  相似文献   
70.
以除尘灰分离炭粉为原料,确定了制备颗粒活性炭的最佳工艺,并对制备的颗粒活性炭进行不同的改性处理和对不同有机蒸气的吸附实验。利用X—光电子能谱仪分析了改性处理后的表面化学性质。吸附实验证明,活性炭的比表面积、表面化学性质和有机物的性质对吸附过程产生影响。  相似文献   
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