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A continuous and high-efficiency process to separate coal bed methane with porous ZIF-8 slurry:Experimental study and mathematical modelling

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Green Energy & Environment 2020年第3期5卷 347-363页

作者： Wan Chen Xiaonan Guo Enbao Zou Mengling Luo Mengzijing Chen Mingke Yang Hai Li Chongzhi Jia Chun Deng changyu sun Bei Liu Lanying Yang Guangjin Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China

Coal bed methane has been considered as an important energy *** major difficulty of purifying coal bed methane comes from the similar physical properties of CH_4 and N_*** ZIF-8/water-glycol slurry was used as a medium to separate coal bed methane by fluidifying the solid adsorbent *** sorption equilibrium experiment of binary mixture(CH_4/N_2)and slurry was *** selectivity of CH_4 to N_2 is within the range of 2-6,which proved the feasibility of the slurry separation *** modified Langmuir equation was used to describe the gas-slurry phase equilibrium behavior,and the calculated results were in good agreement with the experimental data.A continuous absorption-adsorption and desorption process on the separation of CH_4/N_2 in slurry is proposed and its mathematical model is also *** analysis is conducted to determine the operation conditions and the energy performance of the proposed process was also *** gas contains 30 mol%of methane and the methane concentration in product gas is 95.46 mol%with the methane recovery ratio of 90.74%.The total energy consumption for per unit volume of product gas is determined as 1.846 kWh Nm^(-3).Experimental results and process simulation provide basic data for the design and operation of pilot and industrial plant.

关键词： Coal bed methane Gas separation Phase equilibrium experiment Mathematical model Process simulation

Hydrate film growth at the interface between gaseous CO_2 and sodium chloride solution

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Science China Chemistry 2009年第5期52卷 676-682页

作者： PENG BaoZi, sun changyu, CHEN GuangJin, YANG LanYing, ZHOU Wei & PANG WeiXin State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

Greenhouse gas CO2 has become a serious problem for human beings. The hydrate technology has been considered as a possible approach to sequester CO2. In this work, the lateral growth rates of a CO2 hydrate film in aqueous NaCl solutions of different concentrations were measured by means of suspending a single gas bubble in liquid. The results show that the film growth rates depended on not only the driving force, but also the NaCl concentration, and the film growth rates decreased with the increasing NaCl concentration. The simple relationship vf ∝ΔT5/2 could be used to correlate the hydrate film growth rate of a CO2 + NaCl + water system by introducing a NaCl concentration-dependent coefficient. The film thickness was investigated experimentally and evaluated theoretically; the results show that it became thicker at a higher NaCl concentration when the temperature and pressure were specified. In addition, a series of interesting phenomena, such as the occurrence of double hydrate films, were displayed and discussed.

关键词： hydrate interfaces hydrate film growth carbon dioxide sodium chloride

Dissociation behavior of (CH_4+C_2H_4) hydrate in the presence of sodium dodecyl sulfate

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Petroleum Science 2010年第1期7卷 112-117页

作者： Peng Baozi sun changyu Chen Guangjin Tang Xulong Liu Peng Chen Jun Zhang Yanqin State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China High Pressure Fluid Phase Behavior ＆ Property Research Laboratory China University of Petroleum Beijing 102249 China

Separation of a mixture of CH4＋C2H4 gas by forming hydrate in ethylene production has become of interest, and the dissociation behavior of （CH4＋C2H4） hydrate is of great importance for this process. The hydrate formation rate could be increased by adding a small amount of sodium dodecyl sulfate （SDS） into water. In this work, the kinetic data of CH4（18.5 mol%）＋C2H4（81.5 tool%） hydrate decomposition in the presence of 1000 mg.L-~ SDS at different temperatures and pressures were measured with the depressurizing method using a sapphire cell apparatus. The experimental results show that the dissociation rate of （CH4＋C2H4） mixed gas hydrate was large at high temperature and low pressure, and temperature had great influence on the dissociation rate at high pressure. A kinetic model for hydrate dissociation was proposed and the calculated results from the kinetic model were in good agreement with the experimental data. The activation energy for dissociation of the （CH4＋C2H4） mixed gas hydrate was determined to be 43.9 kJ-mol-~, which is lower than that of methane （81.0 ***-~） and ethane （104.0 kJ＇mol-~） hydrate in water （Clarke and Bishnoi, 2004）. As the similar molecular dimensions between ethane and ethylene, the close activation energy need to be provided for ethylene hydrate dissociation. The obtained activation energy of the （CH4＋C2H4） mixed gas hydrate dissociation indicates that the dissociation of the （CH4＋C2H4） mixed gas hydrate is easier than that of pure CH4 or C2H4 gas hydrate.

关键词： Methane ethylene hydrate dissociation SDS

The interference characteristics of platform and towed body noise in shallow water for active/passive towed array sonar

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Chinese Journal of Acoustics 2007年第3期26卷 193-197页

作者： LI Qihu LI Shuqiu sun changyu YU Huabing Institute of Acoustics The Chinese Academy of Sciences Beijing 100080

The interference characteristics of towed platform noise resulted from propeller and towed body for active/passive towed array is analyzed. It is shown that, in shallow water environment, the direct wave and bottom/sea surface reflected wave will seriously affect the performance of sonar system. The formula for calculating the direction of arrival （DOA） of interference in terms of various parameters, such as array depth, length of tow cable, is derived. The effect of interference noise for the detection performance of sonar system is described. The results of system simulation provide the method for reducing the effect of these kind of interferences.

关键词： detection performance interference noise water environment system simulation reflected wave

An efficient method for designing variable digital filters

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Chinese Journal of Acoustics 1997年第1期16卷 1-12页

作者： sun changyu and LI Qihu(Instiute of Aconstics, Academia Sinico Beijing 100080)

The digital filters with adjustable frequency-domain characteristics are called variable filters. Variable filters are useful in the applications where their characteristics are required to be changeable during the course of signal processing. Generally speaking, the variable frequency responses of a variable filters are the functions of a set of spectral parameters defining the desired frequencyUomain characteristics. In this paper, we first sample the given variable maghtode specifications and use them to construct a multi-dimensional (M - D) specification array, then propose an outer product expansion method for expanding it as the sum of the outer products of vectors. Using the outer product expansion, we can simplify the difficult problem of desighng a variable filter as the easy one that only needs constant 1 - D filter designs and 1 - D polynoIhal approximations. The method can obtain variable filters having arbitrary desired variable magnitude characteristics with a high design acctiracy.

关键词： Design IEEE An efficient method for designing variable digital filters

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阵列指向性二次型约束稳健波束形成算法

声学学报 2006年第1期31卷 91-95页

作者：蒋飚朱埜孙长瑜中国科学院声学研究所

提出了一种基于阵列指向性二次型约束的优化算法,以提高最小方差无畸变响应(MVDR)波束形成对方向矢量的稳健性。通过控制阵列波束指向附近的小区域的自适应波束图与期望波束图的加权平方误差,使波束主瓣区域内的信号畸变最小,同时保持... 详细信息

提出了一种基于阵列指向性二次型约束的优化算法,以提高最小方差无畸变响应(MVDR)波束形成对方向矢量的稳健性。通过控制阵列波束指向附近的小区域的自适应波束图与期望波束图的加权平方误差,使波束主瓣区域内的信号畸变最小,同时保持了对约束区间外的干扰信号的抑制能力。数值结果表明:在理想阵形和阵形畸变情况下,无方位失配时,利用本文算法的阵列输出信号与干扰噪声比(SINR)与新近出现的球面约束稳健Capon方法相当,而存在方位失配时,本文算法均优于后者。

关键词：波束形成算法稳健性二次型指向性阵列信号畸变最小方差干扰信号优化算法方向矢量

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气体水合物形成的热力学与动力学研究进展

化工学报 2006年第5期57卷 1031-1039页

作者：孙长宇黄强陈光进中国石油大学(北京)重质油国家重点实验室北京102249

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(vanderWaals Platteeuw模型)和基于双过程水合物... 详细信息

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(vanderWaals 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.

关键词：水合物热力学动力学形成成核生长

Time-domain programmable digital multi-beamforming system

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Chinese Journal of Acoustics 1996年第3期15卷 259-271页

作者： sun changyu LI Qihu sun Zeng QIAO Jun and LIU Zhengyuan(Institute of Acoustics, Academia Sinica, Beijing 100080)

A new beamforming method in time-domain is described in this paper. Based on the pipe line architecture, the variable digital filtering algorithm, rising sampling rate (interpolation), down-sampling rate (decimation), and optimum weighting are combined. The high accuracy time-delay compensation for multi-beam signal processing system is designed by high speed RAM (Random Access Memory) and VLSI (Very Large Scale Integrated) DSP (Digital Signal Processing) chips. Comparing with the traditional beamforming method, the new method presented in this paper is highly accurate, less complex in computation, easy progranunable and have compact hardware architecture. The design philosophy of time-domain RAM-dynamic bearnforming method and hardware implementation is given.

关键词： Time-domain multi-beamforming Variable digital filter Interpolation Decimation Timedelay compensation

含下伏气的第一类天然气水合物藏开发实验与模拟研究进展

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化工进展 2024年第4期43卷 2091-2103页

作者：孙贤柳军王晓辉孙长宇陈光进中国石油大学(北京)化学工程与环境学院北京102249 济宁经济技术开发区管理委员会山东济宁272000

第一类天然气水合物藏由上部含水合物沉积层和下伏气-液两相流层组成,是目前天然气水合物开采的首选目标。本文对第一类天然气水合物藏特征及试采情况进行了介绍,并回顾了相关实验和数值模拟研究进展。实验研究方面总结了第一类水合物... 详细信息

第一类天然气水合物藏由上部含水合物沉积层和下伏气-液两相流层组成,是目前天然气水合物开采的首选目标。本文对第一类天然气水合物藏特征及试采情况进行了介绍,并回顾了相关实验和数值模拟研究进展。实验研究方面总结了第一类水合物储层的重塑方案和该类水合物藏的产气特性。指出第一类水合物藏在储层塑造方面存在一定的局限性,多数实验研究中合成的水合物储层其下伏气是没有多孔介质的纯气体,不能模拟实际带有下伏气层的水合物储层的传质过程。而且,不同产气阶段的产气速率差异明显,初始阶段产气速率明显更快。此外,适用于经典的第三类水合物藏分解特性的建模思路,即将甲烷水合物的分解描述为移动边界问题,假设水合物分解发生在尖锐界面上,不适用于第一类水合物藏分解的数值模拟研究,因为该类水合物储层在分解阶段同时出现多个分解前沿。文中同时提出了有关第一类水合物藏开发未来的研究方向,即扩大研究尺度和模拟自然海洋环境水合物储层受力情况,以更贴近自然水合物成藏环境,提高研究结论的可参考性。

关键词：第一类水合物藏重塑传热传质数值模拟

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