汽油芳构化技术的应用

采用汽油芳构化技术代替催化重整工艺,对某小型炼油厂(500kt/a)进行改造,投资约为催化重整的12%.使原料在HZSM-5分子筛催化剂内表面酸性中心发生裂化、齐聚、环化和脱氢反应,设置3台反应釜,用固定床模拟移动反应,石脑油2釜串联反应、另1釜待命,3釜轮流切换操作,实现连续生产,产物辛烷值＞90#;催化轻汽油采用单釜反应,产物烯烃≤2%.解决了石脑油的低辛烷值及催化轻汽油烯烃质量分数＞62%的双重难题,降低了能耗,延长了催化剂使用寿命,达到了汽油升级的目的.     

表面活性剂强化氧化萃取脱硫过程的实验研究

氧化萃取脱硫过程具有工艺流程简单、设备投资少等优点. 针对氧化过程中存在的反应速度慢、氧化剂用量多等缺点,提出了向反应体系中加入少量水溶性的表面活性剂以提高油水接触几率、强化氧化过程的新思路. 以二苯并噻吩-辛烷为模拟体系,磷钨酸为催化剂,双氧水为氧化剂,通过添加十六烷基三甲基溴化铵,在50℃下可使氧化时间从24 h缩短到7 h,且氧化后油品中硫含量低于10′10-6. 对于实际汽、柴油体系,通过添加表面活性剂,氧化过程中油水相比可从1:1降低为25:1,大大减少了氧化剂用量,且氧化后萃取的单级脱硫率大于50%,优于直接萃取过程的脱硫率.     

满足国Ⅲ、国Ⅳ汽油标准的FCC汽油加氢脱硫技术开发及工业应用

分析了我国FCC汽油的特点及发展趋势,介绍了OCT-M和FRS FCC汽油选择性加氢脱硫技术特点及中试效果,着重介绍了OCT-M和FRS FCC汽油选择性加氢脱硫技术生产国Ⅲ、国Ⅳ汽油的的工业应用效果,标定结果标明,OCT-M和FRS技术成熟可靠,具有装置压力等级低、投资省、操作方便、氢耗低、汽油产品收率高等特点,是我国炼厂生产国Ⅲ、国Ⅳ清洁汽油时可供选择的经济、灵活的解决方案.     

Synthesis,characterization, and ceramization of a carbon-rich SiCw-ZrC-ZrB2 preceramic polymer precursor

A precursor (PBSZ) for SiC_w-ZrC-ZrB₂ hybrid powder was synthesized by chemical reaction of phenol, paraformaldehyde, zirconium oxychloride, boric acid and tetraethylorthosilicate. Results show that zirconium, silicon and boron atoms have been successfully introduced into the branched structure. Decomposition of PBSZ is completed at 800 °C, and it gives amorphous carbon, SiO₂, B₂O₃ and ZrO₂ with a yield of 38% at 1200 °C. During the pyrolysis process, ZrB₂ and SiC form at about 1500 °C, followed by the appearance of ZrC when the amount of B₂O₃ is limited. Highly crystallized ZrB₂–ZrC–C powder with ZrB₂ and ZrC grains evenly distributed in the carbon matrix together with randomly distributed SiC whiskers are obtained after heat-treated at 1800 °C. Further heated at 1900 °C, ZrB₂ and ZrC grains grow from 200 to 500 nm, while SiC whiskers show a much smaller diameter size and tend to grow on the ZrB₂–ZrC–C block surface. The morphology difference is caused by the larger gas supersaturation and accommodation coefficient of the pore channels on the block surface. In addition, defects of the carbon matrix are cumulated to the highest at 1500 °C and the structure-ordered carbon is obtained after heat treated at 1900 °C.     

进气道对缸内直喷增压汽油机性能的影响

应用稳态CFD方法对高、低滚流比进气道进行了分析,高滚流比气道较低滚流比气道流量系数降低16%,滚流比提高22%.基于这两种气道对缸内直喷增压汽油机进气和压缩冲程油气混合的影响进行了瞬态CFD分析.结果表明,高滚流比气道在缸内能形成更规则的大尺度漩涡,且缸内瞬态滚流比更高,两种对称气道瞬态涡流比基本为零,进气道流量系数...     

通用小型汽油机平衡计算与振动激振力分析

通用小型汽油机的振动大小对整机可靠性及噪声有一定的影响.笔者以168F汽油机为研究样机,分析了通用小型汽油机曲柄连杆机构和气缸布置的结构设计特点,对往复惯性力采用过量平衡法的不同曲轴过量平衡量及对整机振动的激振力进行了计算,分析了气缸斜置角度、曲轴过量平衡量和曲轴平衡块的尺寸公差对汽油机的激振力大小的影响,得出小型汽油机的最优平衡量及减小振动激振力变化的方法与措施,控制曲轴平衡块的制造精度能有效地减少批量生产中汽油机的振动变化.     

Products properties from fast pyrolysis of enzymatic/mild acidolysis lignin

The conversion of enzymatic/mild acidolysis lignin (EMAL) isolated from moso bamboo to aromatic chemicals by fast pyrolysis were investigated under nitrogen atmosphere and atmospheric pressure. The experiment of EMAL pyrolyzing was set on a tubular reactor furnace at the temperature levels of 400, 500, 600, 700, 800 and 900 °C, and the products derived from EMAL pyrolyzing were classified into three-phase of gas, condensed liquid (tar), and solid (char). The chemical structure and surface morphology of solid product were characterized by fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), and the ingredients of gas product and liquid (tar) were analyzed with gas chromatography (GC) and gas chromatography/mass spectrometer (GC/MS). The analysis results indicated that the yield of char decreased rapidly from 43% to 28% with an increase of temperature, and the yield of gas product increased gradually from 6% to 26%, and the yield of tar attained a maximum at 700 °C. SEM showed that char took on lots of vesicles that resulted from the gas release from EMAL pyrolyzing. The ingredients of gas product were comprised of H₂, CO, CO₂ and light hydrocarbons (CH₄, C₂H₄ and C₂H₆), and the amount of H₂, CO were high. Besides a huge amount of phenols, the tar contained aromatic hydrocarbons, chain hydrocarbons, monoaromatic aromatic hydrocarbons and some ketones, and the carbon number of chemical compounds were C₆–C₁₀.     

汽油/柴油双燃料高比例预混压燃燃烧与排放的试验

对汽油/柴油双燃料高比例预混燃烧(HPCC)模式的燃烧及排放特性进行了初步的试验研究.结果表明,通过改变柴油的喷射时刻、汽油比例,HPCC呈现出由多种燃烧模式组成的复合燃烧模式,可以实现极低的NOx和碳烟排放,并能保持较高的热效率.试验工况下,汽油比例为50%时,柴油喷油时刻在-58～-6,°CA ATDC时热效率较高,喷油时刻在-49,°CA ATDC和-16,°CA ATDC时分别出现碳烟和NOx排放峰值.进气压力影响HPCC着火滞燃期、燃烧反应速度和"失火"与"爆震"燃烧汽油比例限值,提高进气压力可以提高汽油比例,实现超低的NOx和碳烟排放,并降低HC排放,但CO排放有所升高.随着汽油比例的增加,NOx与碳烟排放降低,对于IMEP为0.5,MPa、汽油比例大于50%时,两者的原始排放分别低于0.4,g/(kW.h)、0.06,FSN,但HC和CO排放升高.     

Experimental and kinetic modeling study of pyrolysis and oxidation of n-decane

The pyrolysis of n-decane was investigated in a flow reactor at 5, 30, 150 and 760 Torr, and the oxidation of n-decane at equivalence ratios of 0.7, 1.0 and 1.8 was studied in laminar premixed flames at 30 Torr. In both experiments, synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) was used to identify combustion species and measure their mole fraction profiles. A new detailed kinetic model of n-decane with 234 species and 1452 reactions was developed for applications in intermediate and high temperature regions, and was validated against the experimental results in the present work. The model was also validated against previous experimental data on n-decane combustion, including species profiles in pyrolysis and oxidation in high pressure shock tube and atmospheric pressure flow reactor, jet stirred reactor oxidation, atmospheric pressure laminar premixed flame, counterflow diffusion flame and global combustion parameters such as laminar flame speeds and ignition delay times. In general, the performance of the present model in reproducing these experimental data is reasonably good. Sensitivity analysis and rate of production analysis were conducted to understand the decomposition processes of n-decane.     

HCCI燃烧技术应用性能研究

均质压燃(HCCI)是一种全新的燃烧方式,它能够有效地提高发动机的燃烧热效率,降低NOx和碳烟的排放。阐述了HCCI燃烧的特点、HCCI燃烧技术的优点、需要解决的技术问题,介绍了将HCCI燃烧技术应用到汽油机、柴油机上的一些方法,最后对HCCI燃烧技术的应用前景进行了展望。