镧化合物对煤间接液化柴油碳烟颗粒摩擦学特性的影响

目的 研究镧化合物对含煤间接液化柴油碳烟润滑油摩擦磨损性能的影响.方法 利用四球长时摩擦磨损试验机,分别考察不同浓度氟化镧(LaF3)和氧化镧(La2O3)对含煤间接液化柴油碳烟(Fischer-Tropsch synthesis diesel soot,F-T DS)与0#柴油碳烟(Diesel soot,DS)白油的润滑性能的影响,利用多功能万能工具显微镜、扫描电镜与能谱、X射线光电子能谱等仪器对磨斑直径、结构、形貌、组成及元素价态进行表征.结果 在含F-T DS白油体系中,添加0.4％(质量分数)镧化合物LaF3或La2O3时,减摩抗磨效果最优,平均摩擦系数(AFC)分别为0.070、0.058,较未添加时(0.094)分别下降25.5％和38.3％,平均磨斑直径(AWSD)分别为0.4318、0.4207 mm,较未添加时减少了33.6％和35.2％.在含DS白油体系中,添加0.6％ 镧化合物LaF3或La2O3时,减摩效果最佳,AFC分别下降11％和16％;添加0.8％ 镧化合物时,抗磨效果最优,AWSD降幅分别为24.8％和33.7％,La2O3抗磨效果优于LaF3.结论 添加少量镧化合物可以改善含F-T DS与DS白油的减摩抗磨效果.其减摩抗磨机理可能是,通过形成转移膜,或在摩擦进程中添加剂吸附在接触表面形成镧系边界润滑保护膜,改善了润滑状态,起到了减摩抗磨作用.     

Ceria‐coated diesel particulate filters for continuous regeneration

The potential of diesel particulate filters wash‐coated with highly dispersed nano‐metric ceria particles for continuous regeneration has been investigated. To this end, catalytic filters were prepared, soot‐loaded (avoiding the formation of the cake layer), and regenerated—under isothermal conditions—at temperature ranging from 200–600°C. Results have shown that catalytic oxidation of soot starts from 300°C and, at all temperatures, the selectivity to CO₂ is higher than 99%. 475°C is the minimum temperature at which the filter is regenerated via catalytic path. At this temperature, the catalytic filter maintains substantially the same performance over repeated cycles of soot loading and regeneration, indicating that the thermal stability of ceria is preserved. This has been further confirmed by comparison between the outcomes obtained from characterization (X‐ray powder diffraction, N₂ adsorption at 77 K, Hg intrusion porosimetry, and scanning electron microscope/energy dispersive X‐ray analysis) of fresh filter and filter subjected to repeated regeneration tests. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3442–3449, 2017     

Studies on the Effect of Physico‐Chemical Soot Properties and Feed Gas Composition on the Kinetics of Soot Oxidation on Fe2O3 Catalyst

Three commercial carbon black samples as well as self‐made C₃H₆ soot were investigated for their reactivity in the oxidation on an α‐Fe₂O₃ catalyst. These studies were performed by temperature programmed oxidation (TPO) using a packed bed. For reference purposes, TPO studies in the absence of the catalyst were made as well. The carbon black samples were characterized towards the content of C, H, N and O as well as higher heating value, specific surface area, moisture and volatile matter and were deemed to be suitable model substances for diesel soot of different maturity. The correlation of these physico‐chemical properties with the kinetics in catalytic TPO indicated that the soot oxidation on Fe₂O₃ is significantly affected by the initial number of surface oxygen compounds of the soot. The decomposition of these surface species causes the formation of active carbon sites, which are supposed to accelerate the soot oxidation.     

不同形态钠对伊敏褐煤碳黑生成特性的影响

为揭示褐煤的碳黑生成特性与Na在煤衍生碳黑形成过程中的作用,采用电感耦合等离子体发射光谱仪、X射线光电子能谱仪和傅里叶变换红外吸收光谱仪研究分别担载了空白、物理吸附态Na (ANa)与离子可交换态Na (INa)的酸洗伊敏褐煤在沉降炉中不同停留时间下热解所产生碳黑的产率、表面与整体化学特性.结果表明:在表面增长阶段,褐煤的碳黑产率增幅远超焦油产率降幅;当停留时间足够长时,碳黑产率有所降低,含氧官能团含量升高;担载Na可以降低碳黑产率,但INa对碳黑的抑制作用比ANa强得多,且INa可以使热解气溶胶中醚与砜的含量升高.这些现象说明:在褐煤二次热解过程中,小分子芳香化合物、脂肪族物质与轻质气体也会通过表面增长提高碳黑产率.褐煤热解气中含氧物质可以在停留时间足够长时表现出对碳黑的氧化作用. INa可以保持与焦炭或挥发分之间有机结合状态,在一次热解过程减少初级焦油释放,在二次热解过程中促进挥发分与含氧物质结合;而ANa在一次热解过程中作用不明显.在二次热解过程中,气化的ANa与INa抑制碳黑形成的作用机制相同.     

中宁电厂锅炉吹灰热控系统的DCS组态设计

介绍了锅炉吹灰控制系统采用DCS组态设计的思路和过程，对系统的工艺流程、功能、硬件和组态设计均作了说明。运行结果表明功能可靠，控制系统运行稳定。     

含氧量对小型生活垃圾焚烧炉污染物排放监测结果的影响

从对小型生活垃圾焚烧炉污染物排放监测实践结果中，总结分析了烟气含氧量对烟尘排放浓度的重要影响关系。指出了含氧量测定不应随机测取，至少应测定3个投料周期取平均值，提出了控制烟气含氧量的建议。     

汽车排气管烟尘磁化率对昆明地区公路边土壤磁化率污染关系的研究

利用环境磁学方法对汽车排气管烟尘6个样品磁化率研究发现,汽车排气管汽油烟尘低频磁化率值为302.9×10-8m3/kg,柴油烟尘低频磁化率值为42.6×10-8m3/kg,远低于昆明地区公路两侧污染土壤的磁化率值。烟尘与土壤混合样品及汽车车身尘土样品研究表明,汽车排气管烟尘及车身对昆明地区公路边土壤的磁化率值不存在直接贡献值,同时对土壤的污染没有直接相关关系。     

利用CA6DL发动机台架评价柴油机油烟炱分散性能的研究

利用国产重负荷柴油机台架(CA6DL)考察了柴油硫含量对柴油机的烟炱生成量及烟炱分散性能的影响,并对比了CA6DL台架的烟炱生成量及黏度增长与美国API规格标准台架MACK T-8E之间的关联性。试验结果表明:柴油硫含量对CA6DL台架的烟炱生成量影响不大,对柴油机油的烟炱分散性能有一定影响;通过适当改变CA6DL发动机工况,可生成大量烟炱并有助于柴油机油分散性能的研究。     

DG-1025/18.2-Ⅱ6型锅炉吹灰特性研究

分析了电站锅炉各受热面吹灰对蒸汽参数的影响,对某发电厂DG-1025/18.2-Ⅱ6型锅炉进行了吹灰方案改进,优化了锅炉吹灰系统吹灰方式,可以按比例减少吹灰次数,减轻了受热面磨损,提高了锅炉的汽温调节性能。