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The dissociation rates of methane hydrates formed with and without the presence of sodium dodecyl sulfate(methane-SDS hydrates),were measured under atmospheric pressure and temperatures below ice point to investigate the influence of the hydrate production conditions and manners upon its dissociation kinetic behavior.The experimental results demonstrated that the dissociation rate of methane hydrate below ice point is strongly dependent on the manners of hydrate formation and processing.The dissociation rate of hydrate formed quiescently was lower than that of hydrate formed with stirring;the dissociation rate of hydrate formed at lower pressure was higher than that of hydrate formed at higher pressure;the compaction of hydrate after its formation lowered its stability,i.e.,increased its dissociation rate.The stability of hydrate could be increased by prolonging the time period for which hydrate was held at formation temperature and pressure before it was cooled down,or by prolonging the time period for which hydrate was held at dissociation temperature and formation pressure before it was depressurized to atmospheric pressure.It was found that the dissociation rate of methane hydrate varied with the temperature(ranging from 245.2 to 272.2 K) anomalously as reported on the dissociation of methane hydrate without the presence of surfactant as kinetic promoter.The dissociation rate at 268 K was found to be the lowest when the manners and conditions at which hydrates were formed and processed were fixed. 相似文献
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The systematic experimental studies were performed on the hydrate formation kinetics and gas-hydrate equilibrium for a simulated catalytic cracking gas in the water-in-oil emulsion. The effect of temperature, pressure and initial gas-liquid ratio on the hydrate formation was studied, respectively. The data were obtained at pressures ranging from 3.5 to 5 MPa and temperatures from 274.15 to 277.15 K. The results showed that hydrogen and methane can be separated from the C2+ fraction by forming hydrate at around 273.15 K which is much higher temperature than that of the cryogenic separation method, and the hydrate formation rate can be enhanced in the water-in-oil emulsion compared to pure water. The experiments provided the basic data for designing the industrial process, and setting the suitable operational conditions. The measured data of gas-hydrate equilibria were compared with the predictions by using the Chen-Guo hydrate thermodynamic model. 相似文献
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单纯降压法开采天然气水合物容易遇到地层传热速率慢的问题导致体系温度压力长期处于相平衡状态,因而严重拉长了开采时间。为解决降压法开采过程中低温区域水合物分解过慢的问题,本文利用三维装置研究了注化学剂法开采过程中水合物分解和产气规律。根据反应釜内温度和压力的变化,全面分析了注入过程、焖井过程对水合物分解的影响。结果表明,对于单井吞吐法,在注入抑制剂阶段可以刺激水合物快速分解,但不宜采用过大的注入量和过多的注入次数,过大的注入量和注入次数会增大堵塞风险导致开采时间被大大延长。相较于小型实验装置,中试级别实验由于注入时间长,抑制剂在注入阶段已经得到较为充分的运移,因而焖井时间不能过长,控制在40min左右为宜。 相似文献
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本刊讯1月18,公安部消防局警务处副处长谭雍一行就总队2010年冬季新兵训练、部队管理、规范化建设等进行了督察和调研。 相似文献
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气体水合物形成的热力学与动力学研究进展 总被引:1,自引:0,他引:1
气体水合物形成过程中涉及复杂的热力学和动力学问题.本文对水合物热力学理论模型、水合物生成动力学机理等方面的研究成果和最新进展进行了综述.热力学方面重点介绍了基于等温吸附理论 (van der Waals-Platteeuw模型)和基于双过程水合物生成机理(Chen-Guo模型)的相平衡热力学模型,同时介绍水合物结构及其转变方面的最新研究成果.动力学方面介绍了成簇成核、界面成核等成核机理模型以及成核后的水合物生长机理.另外还述及了目前水合物热力学和动力学研究中所涉及的微观、亚微观和宏观测量方法.针对目前水合物热力学和动力学研究中存在的问题,对未来的发展方向和重点提出了建议. 相似文献
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扩展了立方扰动硬链(CSPHC)状态方程在天然气工业中通常遇到物质的纯组分参数, 并建立了纯组分参数的普遍化关联式; 将过量Gibbs自由能混合规则引入CSPHC状态方程, 以应用于高度非对称体系与极性体系相平衡性质计算。结合MPHC活度系数模型及Wilson 活度系数模型, 对13组二元体系的汽液平衡性质获得较满意的结果。 相似文献
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扩展了立方扰动硬链(CSPHC)状态方程在天然气工业中通常遇到物质的纯化分参数。并建立了纯组分参数的普遍化关联式;将过量Gibbs自由能混合规则引入CSPHC状态方程,以应用于高度非对称体系与极性体系相平衡性质计算。结合MPHC活度系数模型及Wilson活度系数模型,对13组二元体系的汽液平衡性质获得较满意的结果。 相似文献
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