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531.
建立了烧结烟气中SO3的检测技术,包括SO3的采集装置和测定方法。实验结果表明:质量分数为80%的异丙醇适宜作为吸收液,方法的回收率为95.79%~102.80%,相对标准偏差为0.46%~1.38%。该技术能有效消除烟气中粉尘及SO2对测定的干扰,具有准确、可靠、方便等特点,可应用于烧结烟气脱硫等装置日常运行中SO3含量的测定。 相似文献
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533.
采用共沉淀法制备了一种新型催化剂——铁铈钛复合氧化物催化剂,研究了Fe掺加量、体积空速以及H2O和SO2的加入对其选择性催化还原NO性能的影响;采用XRD和SEM等手段对催化剂的结构和形貌进行了表征。表征结果显示,Fe的掺加使催化剂表面的颗粒更均匀,提高了催化剂的分散度。实验结果表明:以Ce(NO3)3,Fe(NO3)3?9H2O,TiOSO4?2H2O为原料、按n(Ce)∶n(Fe)∶n(Ti)=0.2∶0.8∶1配比制得的Ce0.2Fe0.8TiOx为催化剂,在反应温度250 ℃、反应时间3 h、体积空速25 000 h-1的条件下,NO去除率为99.8%,N2选择性为100%;Fe的掺加显著提高了Ce0.2Fe0.8TiOx催化剂的抗H2O和SO2的能力。 相似文献
534.
研究了载硫温度、硫炭比(简称S/C),吸附温度等因素对载硫活性炭的硫含量、脱汞能力以及硫损失的影响,探讨载硫活性炭制备的工艺条件优化。结果表明,不同载硫温度下制备的载硫活性炭的气态Hg0吸附能力远强于原料活性炭;载硫温度不同时,负载到活性炭孔隙或表面上的硫的形态不同,导致了脱汞能力的差异,较合适的载硫温度为350℃;S/C为5%(质量分数,下同)时,随着吸附温度的升高,载硫活性炭的气态Hg0吸附量降低;在一定的载硫温度下,原料中S/C越高时,制备的载硫活性炭的硫含量越高、气态Hg0吸附能力越强,但其硫损失率也越高,从实际的使用效果来看,较合适的S/C为10%。 相似文献
535.
Biomarkers and low-molecular weight polyaromatic compounds have been extensively studied for their fate in the environment. They are used for oil spill source identification and monitoring of weathering and degradation processes. However, in some cases, the absence or presence of very low concentration of such components restricts the access of information to spill source. Here we followed the resistance of high-molecular weight sulfur-containing aromatics to the simulated weathering condition of North Sea crude oil by ultra high-resolution Fourier transform ion cyclotron resonance mass spectrometry. The sulfur aromatics in North Sea crude having double bond equivalents (DBE) from 6 to 14 with a mass range 188-674 Da were less influenced even after 6 months artificial weathering. Moreover, the ratio of dibenzothiophenes (DBE 9)/naphthenodibenzothiophenes (DBE 10) was 1.30 and 1.36 in crude oil and 6 months weathered sample, respectively reflecting its weathering stability. It also showed some differences within other oils. Hence, this ratio can be used as a marker of the studied crude and accordingly may be applied for spilled oil source identification in such instances where the light components have already been lost due to environmental influences. 相似文献
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537.
以钛酸四丁酯为钛源,硫脲为掺硫前驱物,采用聚乙二醇辛基苯基醚(Triton X-100)/正己醇/环己烷/氨水的微乳液体系合成了掺硫的纳米TiO2粉体;对其结构进行了表征,以甲基橙为目标降解物考察了其光催化性能.烧结温度通过影响TiO2的晶型转变和颗粒尺寸来影响其光催化性能,随着烧结温度的升高,TiO2的光催化性能先是... 相似文献
538.
539.
This study focused on steam gasification and reforming of waste biomass using a reforming catalyst. The purpose of the study was to evaluate the durability of a commercial Ni reforming catalyst and the effect of CaO on the reforming behavior, and to clarify detailed factors of catalytic performance, as well as the effect of operating parameters on the characteristics of produced gas composition. Moreover, catalyst regeneration was carried out and the behavior of catalytic activity based on gas composition was investigated. Using a fluidized bed gasifier and a fixed bed reformer, gasification and reforming of waste biomass were carried out. Commercial Ni-based catalyst and calcined limestone (CaO) were applied to the reforming reaction. Temperature of the gasifier and reformer was almost 1023 K. Ratio of steam to carbon in the feedstock [mol mol−1] and equivalence ratio (i.e., ratio of actual to theoretical amount of oxygen) [-] were set at about 2 and 0.3, respectively. The feed rate of the feedstock into the bench-scale gasifier was almost 15 kg h−1. The results of waste biomass gasification confirmed the improvement in H2 composition by the CO2 absorption reaction using the reforming catalyst and CaO. In addition, CaO proved to be especially effective in decreasing the tar concentration in the case of woody biomass gasification. Catalytic activity was maintained by means of catalyst regeneration processing by hydrogen reduction after air oxidation when woody biomass was used as feedstock. 相似文献
540.
随着脱硫装置的大量投运,燃煤硫分、运行人员操作水平、检修人员技术能力都直接影响着脱硫系统的安全性和经济性。结合钱电公司的运行实际,当燃煤硫分和负荷的变化,原烟气的SO2浓度低于2300mg/m3,采用2泵运行;SO2浓度超过2300mg/m3时,采用3泵运行,脱硫效率均能达到设计要求。为此,降低脱硫系统入口SO2浓度是提高优化运行的关键。脱硫系统在线仪表的准确性和数据的有效性,直接关系到脱硫系统的考核和脱硫电价的补助,对脱硫系统的安全、经济运行起到至关重要的作用。 相似文献