稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业应用

介绍了浙江石油化工有限公司新建的3 Mt/a柴油加氢精制装置，其配套使用中国石化石油化工科学研究院有限公司开发的催化剂级配技术，并实施了可根据原料供应及市场产品需求情况灵活调整切换的2种生产技术方案。1 a的安稳生产运行结果表明:该装置以直馏柴油为主原料，通过分馏塔的馏分切割及其侧线抽出，实现了稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业化应用；在实施以兼产喷气燃料为主的生产技术方案时，通过调整常一线柴油的掺炼量，不仅可以生产含硫量小于10.0 μg/g的精制柴油产品，同时兼产所得到的喷气燃料产品含硫量小于0.5 μg/g，赛波特颜色号值大于30；在实施主产精制柴油组分方案时，通过掺炼质量分数为20%~40%的催化柴油，并使所提炼得到的精制柴油组分含硫量小于6.0 μg/g的前提下，这些精制柴油组分产品既可直接作为满足国Ⅵ柴油产品出厂待售，也可作为柴油调和组分储存待用于产品的进一步优化。     

Physiochemical structure of semicoke derived from co-carbonization of coal and sawdust blends

The substitution of coal blending with sawdust had been widely investigated for metallurgical coke production. In this paper, the physiochemical structures of the semicoke derived from sawdust/coals blends co-coking were characterized by several analytical techniques including FTIR-ATR, XPS, NMR, OM, and SEM. Meanwhile, the influence of the sawdust on the physicochemical properties of the sawdust/coals blends were also investigated. Results indicated that partial substitution of coal blending with sawdust benefited from the formation of colloid and optical anisotropy due to the positive synergetic effect, whereas high proportion of sawdust (>10 wt%) inhibited the agglomeration of semi-coke. On the other hand, the semicoke consisted primarily of aromatic carbons replaced by the oxygen linked to carbons and aliphatic carbons when the coal blending was replaced by high proportion of sawdust, causing a less polyaromatic graphite-like structure formation in the semicoke.     

提高新疆准东露天煤成浆性的实验研究

为提高准东露天煤的成浆性能,利用宽沟煤、乌东煤、北山煤、黑山煤、红沙泉煤5种煤与准东露天煤进行了混合制浆实验,考察了各单种煤的成浆性能以及单种煤最高成浆浓度条件下混合制浆的煤浆性能。单一准东露天煤浆的成浆性研究表明:准东露天煤单独制浆时,在添加剂添加率3‰下,煤浆最高质量分数为47%,黏度650 mPa·s,但煤浆流动性和稳定性一般。与不同种煤混合制浆研究表明:准东露天煤与宽沟煤、黑山煤容易混合成浆,煤浆的浓度、流动性、稳定性均有明显提高;在准东露天煤与宽沟煤、黑山煤质量比5∶5时,煤浆质量分数可达57%,可满足水煤浆气化炉生产对煤浆的要求。     

利用调度优化模型研究原油调合方案的可行性

针对某沿海炼油企业拟投用原油调合系统以稳定混炼原油的性质,设计方案要求将部分码头罐的操作模式由混储改为单储的情况,采用约束规划与数学规划复合建模,实现了码头至厂区大容积长输线模拟,建立了该企业的原油调度优化模型并研究了设计方案的可行性。针对240h调度周期、10种可加工原油、3艘到港油轮的复杂工况进行了优化计算。结果表明:该设计方案具备可行性,且油轮仍可实现到港即卸油,蒸馏装置混炼油种也可长时间保持稳定;模型的优化计算时间较短(小于15min),且对长输线收付及存油情况模拟准确,复合建模方法满足工业应用要求。     

基于虚拟化技术的在线开放课程建设研究--以“常用工具软件”课程为例

随着互联网的迅猛发展,建设在线开放课程成为高职院校信息化教学改革的一个方向。首先通过分析国内外的在线课程现状,发现阻碍在线课程发展的共性问题;然后对"常用工具软件"课程现状进行深入调查、分析和研究,提出将虚拟化技术应用到课程建设中以解决网络教学遇到的问题;最后将研究结论应用到教学实践中,用于提升学生专业能力,提高教学效果。     

Numerical investigation into the decoupling effects of hydrogen blending on flame structure and soot formation in a laminar ethylene diffusion flame

Numerical calculations were conducted to explore the various effects of hydrogen blending on flame properties and soot behaviors in an ethylene coflow diffusion flame, based on a fully step-by-step decoupling method, by introducing several virtual species into the gas-phase mechanism. Results show that the concentration of OH increases under the chemical effect of hydrogen due to an enhanced rate of H₂ + O ↔ OH + H. The soot yield, primary number density, and average primary number per aggregate decrease under dilution effect while these increase under chemical effect. The enhancements of hydrogen-abstraction-carbon-addition (HACA) rates and polycyclic aromatic hydrocarbon (PAH) condensation rates are responsible for soot mass addition under chemical effect. Both the oxidation rates by O₂ and OH are delayed under the chemical effect because of lower concentrations of O₂ and OH in the sooting zone. The overall effect of higher surface growth rates and delayed oxidation rates results in an increased soot volume fraction (SVF).     

Synergistic effect for co-coking of sawdust and coal blending based on the chemical structure transformation

Biomass was used as additives in coal blending for making coke in terms of widening the alternative raw materials and reducing CO₂ emissions. To obtain the influences of biomass incorporation on the semicoke formation, the chemical structure transformation as well as the gas evolution during sawdust (SD)/coal blending (BC) co-coking were investigated using in-situ Fourier transform infrared spectroscopy coupled with mass spectrometry (In-situ FTIR-MS). Meanwhile, the role of biomass in the semicoke formation was also characterized by several analytical techniques. The transformation of the five main functional groups between SD and BC exhibited the largest difference, and the synergistic effect based on the chemical structure transformation was also proposed for the SD/BC blends co-coking. The synergistic effect based on the chemical structure transformation was divided into two stages during semicoke formation. One stage occurred at 100–280 °C that was assigned to the physical effect that inhibited the BC decomposition. Another stage happened at 280–500 °C that was mainly attributed to the hydrogen transfer that enhanced the aromatization of semi-coke. In addition, it was also noted that the thermoplastic properties decreased proportionately to the quantity of the SD, and the non-agglomeration between BC and SD was clearly observed by SEM.     

天麻提取酒液与天麻渣液态发酵酒的调配酒初探

为开发一种含有天麻素的调配酒,采用固态白酒浸泡的方式提取天麻素得到天麻提取液,并利用剩余天麻渣进行液态发酵酿酒,将天麻提取酒液与天麻渣液态发酵酒按一定比例调配得到一种新型的天麻调配酒。采用单因素及正交试验确定天麻素最佳提取条件,并探究不同调配比例对酒感官的影响。试验结果表明:提取天麻素的最佳条件为提取温度100℃、固液比1:15、提取时间60 min;在液态发酵阶段,添加天麻渣可以提高酒液的酒精度发酵速率,且最佳添加量为8%;天麻提取酒液与天麻渣液态发酵酒的调配比例为1:3,其感官总评分为99分,所得调配酒清亮透明且无悬浮物、香气纯正且有轻微天麻药香、口感酣厚且回味持久。最终证实了利用天麻提取酒液与天麻渣液态发酵酒开发调配酒具有一定的可行性。     

Dynamic optimization for gas blending in pipeline networks with gas interchangeability control

The increasing penetration of unconventional gas and liquefied natural gas poses an operational challenge on existing regional gas networks for gas quality problems. A new dynamic model for natural gas pipeline network with multiple supplies is presented with a special emphasis on gas interchangeability control. Wobbe index serves as gas interchangeability indicator and is calculated by equations derived from rigorous composition-based partial differential equations. Disjunctive formulation is applied to represent different modes of gas blending due to gas reversal, and the disjunctive model is then reformulated as a nonsmooth model with min/max and absolute value functions, which is solved by a gradient-based nonlinear program solver after smooth approximation. Moreover, a heuristic algorithm is proposed to tune the penalty parameters in order to focus on different penalty terms while keeping the model well-conditioned. The developed model and strategy are first tested with a small pipeline network model and then extended to a large model. The results show that the model can effectively manage gas interchangeability issues in pipeline networks within reasonable CPU time.     

Effect of the composition and degree of crosslinking on the properties of poly(l‐lactic acid)/crosslinked polyurethane blends

Poly(l ‐lactic acid)/crosslinked polyurethane (PLLA/CPU) blends which were prepared via reactive blending of PLLA with poly(?‐caprolactone) (PCL), glycerol and 4,4′‐methylenediphenyl diisocyanate showed excellent toughness. The effects of the composition of the mixture and degree of crosslinking of CPU on the toughness of the PLLA/CPU blends (80/20 w/w) were studied in detail. Dynamic mechanical analysis and rheological measurements were used to characterize the structure of the in situ formed CPU in the PLLA matrix. A novel netlike phase structure was observed when the average molecular weight of PCL and degree of crosslinking were 1 kDa and 10%, respectively. The impact strength of the blend was enhanced from 2.2 kJ m^?2 for pure PLLA to 62.4 kJ m^?2; meanwhile, the elongation at break was increased to 489.8%. Therefore, the mechanical properties of PLLA/CPU blends can be easily tailored by tuning the composition of the mixture and the degree of crosslinking of CPU. © 2018 Society of Chemical Industry