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21.
超稠油供氢水热裂解改质降黏研究   总被引:25,自引:3,他引:25  
通过超稠油水热裂解反应前后黏度、沥青质、硫质量分数等性质的变化,研究了超稠油进行水热裂解的主要影响因素及规律。结果表明,超稠油中含有一定量的硫是地层注蒸汽温度下进行水热裂解反应的前提。温度和时间对反应有很大影响。供氢剂中四氢萘对超稠油水热裂解影响最大。四氢萘供氢剂与硫酸镍催化剂复配使用对超稠油水热裂解有协同效应。水热裂解物理模拟实验表明,胜利单家寺油田超稠油通过供氢催化水热裂解降黏率可达70%以上。胶质、沥青质、硫质量分数降低,H/C原子比提高,超稠油得到一定程度的改善。  相似文献   
22.
本文采用2011~2018年上市制造业企业数据,选用基于B-样条展开的非参数分位数模型实证研究影子银行化对企业升级的非线性异质影响,结果发现:(1)企业影子银行化对企业升级影响的拟合曲线具有非线性特征,大致呈“倒U形”,说明企业影子银行活动存在最有效规模;(2)位于不同分位点企业影子银行化存在显著异质性,表现为:企业层级水平越高,拟合曲线曲率越大,即敏感度越高,影子银行活动的最有效规模越低;(3)产权性质不同的企业影子银行化最优规模也存在异质性,非国有企业最优点高于国有企业,并且低分位点非国有企业主要表现促进作用;(4)适度的影子银行活动会缓解企业面临的融资约束和促进企业创新投资从而有利于企业升级,而过度的影子银行活动则会加强融资约束不利于企业升级。  相似文献   
23.
构建了信息产业发展与区域产业结构高度化的指标体系,利用基于OWA算子的灰色关联模型融合方法测算了电子信息产业发展与区域产业结构高度化的关联程度.结果表明,电子信息产业的发展是区域产业结构高度化的重要支撑力.东部地区的信息产业发展与区域产业结构高度化指标体系中的环保资金投入增加量和第三产业增加值的关联度较高.中部、西部地区的信息产业发展与新兴产业产值的关联程度较大.从全国范围来看,信息产业的科技创新转化能力对产业结构高度化的推动作用仍较低.  相似文献   
24.
25.
The conversion of H2 into methane can be carried out by microorganisms in a process so-called biomethanation. In ex-situ biomethanation H2 and CO2 gas are exogenous to the system. One of the main limitations of the biomethanation process is the low gas-liquid transfer rate and solubility of H2 which are strongly influenced by the temperature. Hydrogenotrophic methanogens that are responsible for the biomethanation reaction are also very sensitive to temperature variations. The aim of this work was to evaluate the impact of temperature on batch biomethanation process in mixed culture. The performances of mesophilic and thermophilic inocula were assessed at 4 temperatures (24, 35, 55 and 65 °C). A negative impact of the low temperature (24 °C) was observed on microbial kinetics. Although methane production rate was higher at 55 and 65 °C (respectively 290 ± 55 and 309 ± 109 mL CH4/L.day for the mesophilic inoculum) than at 24 and 35 °C (respectively 156 ± 41 and 253 ± 51 mL CH4/L.day), the instability of the system substantially increased, likely because of a strong dominance of only Methanothermobacter species. Considering the maximal methane production rates and their stability all along the experiments, an optimal temperature range of 35 °C or 55 °C is recommended to operate ex-situ biomethanation process.  相似文献   
26.
采用间歇超临界水(supercritical water, SCW)反应器,考察了三种煤焦油及其组分在SCW中的反应性。实验结果表明,沥青质裂解活性高的煤焦油在SCW中反应,轻质产物多,轻质化效果好。沥青质是轻质化反应的主要组分,它发生两极分化反应生成轻油和残焦。与常压N2热解相比,SCW可以促进沥青质转化为轻油并抑制缩合成焦的反应。由沥青质组分反应产物推断,煤焦油沥青质的芳香核主要是由1~4环的芳香族化合物构成。轻油组分在SCW中较为稳定,不足10%的轻油转化为沥青质和残焦。残焦组分在SCW中不发生反应。基于各组分的反应,探讨了煤焦油组分在SCW中的反应路径。  相似文献   
27.
阿尔伯塔的油砂资源日益成为北美重要的战略性能源供给.本实验室通过采用碱性条件下在高岭土表面上组装菱沸石的方法,合成了新型的菱沸石-粘土复合材料,并证明此复合材料是比菱沸石更好的油砂沥青精制剂.XRD,SEM,TEM,N2物理吸附和XPS表面元素分析结果表明,菱沸石-粘土复合材料具有大体积烃类分子可及的独特的外表面,该复合材料不仅可降低油砂沥青的裂解反应温度,同时还可大幅度脱除沥青中的硫、氮、镍和钒等杂质.  相似文献   
28.
The cost of membrane separation processes for removing CO2 and H2S from low-quality natural gas can be reduced for some concentration ranges of CO2 and H2S by utilizing concurrently two different types of polymer membranes, one with a high CO2/CH4 selectivity and the other with a high H2S/CH4 selectivity. The polymers considered in this exploratory study were 6FDA-HAB polyimide for the removal of CO2 and [poly(ether urethane urea)] (PEUU) for the removal of H2S. It was required that the concentrations of CO2 and H2S in low-quality natural gas be reduced to US pipeline specifications (≤2 mol% CO2 and ≤4 ppm H2S). Low-quality natural gas was simulated in this study by CH4/CO2/H2S mixtures containing up to 40 mol% CO2 and 10 mol% H2S. Twenty-seven membrane process configurations (PCs) were examined by computer simulations and optimized in order to determine the most economical configurations. Part I of this study considered only PCs without recycle streams [J. Hao, P.A. Rice, S.A. Stern, Upgrading low-quality natural gas with H2S- and CO2-selective polymer membranes. Part I. Process design and economics of membrane stages without recycle streams, J. Membr. Sci. 209 (2002) 177–206]. In Part II, reported below, the study was extended to two- and three-stage PCs with various recycle options. A sensitivity analysis was also made to determine the effects of variations in feed flow rate, feed pressure, membrane module cost, and wellhead price of natural gas on process economics. The economically optimal PCs were found to be either two membrane stages connected in series with or without recycle streams or single stages without recycle, depending on feed composition and selected operating conditions. The optimal two-stage PCs with recycle streams would utilize the H2S/CH4-selective membranes in the first stage and either the CO2/CH4 or the H2S/CH4-selective membranes, or both, in the second stage. Three-stage membrane PCs were not found to be economically competitive under the conditions assumed in this study.  相似文献   
29.
Biogas is upgraded using an absorption with water-wash technique by 11 of a total of 14 upgrading plants in Sweden. However, problems with microbial growth on the pall rings in the absorption column, and in one case in the desorption column, have a negative impact on the upgrading of raw gas to vehicle gas. Five of the nine biogas plants studied here have experienced problems with microbial growth. The objectives of this study were to identify such microbial growth and to determine possible factors for its control, in order to provide recommendations for process management. A questionnaire was sent out and visits were made to the upgrading plants to collect information about the upgrading process. Phospholipid fatty acid (PLFA) analysis was performed to determine microbial biomass and community structure in samples from four upgrading plants. In samples from two of the plants, methane-oxidizing bacteria (type I methanotrophs) were indicated, while samples from one of the other plants showed biomarkers indicating actinomycetes. Factors affecting development of microbial growth were found to be water quality and the pH and temperature of the process water. Plants that used wastewater in the upgrading process experienced far more problems than those using clean water of drinking quality.  相似文献   
30.
碱处理HZSM-5分子筛在线催化提质生物油   总被引:1,自引:0,他引:1  
采用NaOH溶液对HZSM-5分子筛进行碱处理,利用XRD、SEM、BET、Py-FTIR四种方法表征改性HZSM-5分子筛,对生物原油有机相、未改性HZSM-5制得生物油有机相与改性HZSM-5制得生物油有机相进行理化特性及成分分析,研究了碱处理HZSM-5分子筛对生物油有机相产物的影响;对使用了120 min的三种失活催化剂进行了热重分析,并对焦炭峰面积进行了积分计算。结果表明,经过碱处理后的HZSM-5分子筛保留了典型的MFI拓扑结构,形成了一定数量的介孔;同时,经碱处理1 h的HZSM-5分子筛催化制得的生物油有机相产物的产率有所增加且理化特性得到提高,其产物中烃类物质的含量显著增加,达到了37.67%,且以单环芳香烃为主;同时改性HZSM-5分子筛对生物油有机相中的酸、醛及酮类物质均有较好的脱除效果,有效地降低了生物油的腐蚀性并提升了生物油的稳定性,热值达到了35.32 MJ/kg;经1 h碱处理的HZSM-5分子筛的总结焦量明显降低。  相似文献   
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