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91.
1200kt/a乙烯改扩建工程是大庆石化公司"十一五"发展的重点工程。文中以该工程的工艺及热力管网改造项目为例,从工程概况、材料计划、施工方案编制、过程经营、成本控制、风险防范等方面,探讨了管网改造项目的实施方案。 相似文献
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93.
Shyh-shin Hwang Sung-po Liu Peming P. Hsu Jui-ming Yeh Jui-pin Yang Chiu-lin Chen 《International Communications in Heat and Mass Transfer》2012
Ethylene vinyl acetate (EVA)/montmorillonite (MMT) nanocomposites diluted from master batch (50 wt.%) with EVA and EVAgMA was used in this study. The organoclay EVA nanocomposites were then injection molded by conventional and microcellular methods. Nitrogen was used as the blowing agent. The effect of organoclay content and MA grafted EVA on the morphology and the mechanical and rheological properties of the EVA–clay nanocomposites were then investigated. The results showed that the mechanical properties (tensile and impact) increased as the clay content increased. Cell size decreased as the clay loading increased. The EVAgMA nanocomposites had better mechanical properties than the EVA nanocomposites. XRD results showed that the EVAgMA nanocomposites have an exfoliated layered structure while the EVA nanocomposites are intercalated. Rheological results showed the viscosity is clay loading dependent and that the shear thinning effect occurs at high shear rates. 相似文献
94.
To conduct a well‐planned plant shutdown, so as to reduce flare emissions for the sake of plant profitability and local environmental sustainability, one of the primary tasks is to perform comprehensive and precise accountings for flare emissions. Since the literature is still lacking systematic and quantitative studies, plant‐wide dynamic simulations are employed to simulate an ethylene plant shutdown and characterize its flare emission sources through which dynamic emission profiles of various emission species changing with respect to time are obtained. Plant shutdown emission inventories are enriched with details for point emission sources, and possible technical supports are provided to both industry and environmental agencies on evaluating and developing cost‐effective flare minimization strategies in the future. 相似文献
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96.
《International Journal of Hydrogen Energy》2020,45(30):15254-15262
This study is to convert renewable H2 and increasingly concerned CO2 to ethylene or C2H4 over Fe3.33Co1.67K5/ZrO2 and Fe3.33Co1.67K5/Al2O3 catalysts. The ZrO2 support provides amounts of surface oxygen vacancies (OVs) as well as stable and rich surface hydroxyl groups (-OH), which promotes the Fe3.33Co1.67K5/ZrO2 catalysts with 5% Fe and Co loadings to achieve C2H4 space time yield (STY) of 0.064 mmolC2H4∙m−2cat∙h−1 at 290 °C and 2.0 MPa, while the Fe3.33Co1.67K5/Al2O3 catalysts only reach C2H4 STY of 0.009 mmolC2H4∙m−2cat∙h−1 at 330 °C and 2 MPa Fe3.33Co1.67K5/ZrO2 catalysts are very promising for converting the captured CO2 and renewable H2 to highly demanded C2H4. This work not only provides a guideline for developing efficient catalysts but also advances the mechanistic understanding of catalytic CO2 hydrogenation. 相似文献
97.
Heterogeneous Reactor Modeling of an Industrial Multitubular Packed‐Bed Ethylene Oxide Reactor
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Zeeshan Nawaz 《化学工程与技术》2016,39(10):1845-1857
The one‐dimensional heterogeneous model of an industrial multitubular packed‐bed ethylene oxide (EO) reactor was developed using the equation‐oriented platform Aspen Custom Modeler. Reactor operation was optimized in terms of maximized EO production and selectivity and enhanced safety related to the presence of oxygen in the EO reactor. Good agreement was found between the model results during validation against the available information under identical operating conditions. The model predicts the behavior of the EO reaction and demonstrates the extent of catalyst utilization with product distribution, product yield, by‐product formation, temperature and concentration profiles, over time and along the length of the reactor or catalyst bed. The model sensitivity studies compute the optimum feed flow, oxygen concentration, feed pressure, etc. and suggest the best operational philosophy. 相似文献
98.
In this study basic oxygen and stainless steel slag were both assessed for potential use in treating acid mine drainage. The stainless steel slag was able to effect some pH change but was found to not be suitable. Basic oxygen slag was found to have a significant potential as a remediating agent. For a model acid mine water with a pH of 2.5, sulfate concentration of 5000 mg/L and iron concentration of 1000 mg/L, the slag was able to increase pH to 12.1, reduce the soluble iron by 99.7% and reduce sulfate by 75% in batch experiments. In these batch reactors most reaction was completed within 30 min indicating that this is a rapid process. Additional experiments were conducted with continuous flow reactors to assess the maximum treatment capacity of the slag. These experiments indicated that slag replacement strategies are wholly dependent on the strength of the acid mine drainage, the required residence time and the specified residual concentrations of iron or sulfate and the pH. The data indicate that in particular, basic oxygen furnace slag has significant potential as a replacement reagent for lime in treating acid mine drainage. 相似文献
99.
Fang-Qi Shao Jiu-Ju Feng Zhong-Zhi Yang Sai-Sai Chen Junhua Yuan Ai-Jun Wang 《International Journal of Hydrogen Energy》2017,42(39):24767-24775
Herein, a simple one-pot aqueous method was developed for synthesis of AgPt hollow alloyed nanostructures (AgPt HANS) with polyvinylpyrrolidone (PVP) and cytosine as the dispersing agent and eco-friendly growth-director, respectively. The synthesized architectures displayed the improved catalytic performance toward ethylene glycol oxidation reaction (EGOR) relative to commercial Pt black in alkaline media. Meanwhile, the catalyst exhibited the enhanced catalytic activity for hydrogen evolution reaction (HER) with the positive onset potential (Eonset, ?39 mV) and a small Tafel slope (40 mV dec?1) relative to commercial Pt/C (20 wt%, ?31 mV, 33 mV dec?1) in 0.5 M H2SO4, along with the more positive Eonset (?34 mV) and a smaller Tafel slope (59 mV dec?1) in 0.5 M KOH compared with Pt/C (?35 mV, 85 mV dec?1). 相似文献
100.
Thermoplastic vulcanisates (TPVs) based on ethylene–vinyl acetate copolymer (EVA)/styrene–butadiene rubber (SBR) blends were prepared by dynamic vulcanisation, with the TPVs being reinforced by carbon black (CB). Experimental results indicated that the mechanical properties of dynamically vulcanised EVA/SBR blends were enhanced remarkably by the incorporation of CB. Morphology study showed that the SBR particles with average diameter of 20?μm were dispersed evenly on the etched surface of EVA/SBR/CB TPVs. The Mullins effect could be observed in the stress–strain curves of EVA/SBR TPVs and EVA/SBR/CB TPVs during the uniaxial loading–unloading cycles. Compared with EVA/SBR TPVs, CB reinforced EVA/SBR TPVs had the relatively higher stress, residual deformation and internal friction loss. 相似文献