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Optimization strategy and procedure for coal bed methane separation 被引量:3
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作者 Gaobo Zhang Shuanshi Fan +3 位作者 Ben Hua Yanhong Wang Tianxu Huang Yuhang Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第3期533-541,共9页
Coal bed methane (CBM) has a huge potential to be purified to relieve the shortage of natural gas meanwhile to weaken the greenhouse effect. This paper proposed an optimal design strategy for CBM to obtain an integr... Coal bed methane (CBM) has a huge potential to be purified to relieve the shortage of natural gas meanwhile to weaken the greenhouse effect. This paper proposed an optimal design strategy for CBM to obtain an integrated process configuration consisting of three each single separation units, membrane, pressure swing absorption, and cryogenics. A superstructure model was established including all possible network configurations which were solved by MINLP. The design strategy optimized the separation unit configuration and operating conditions to satisfy the target of minimum total annual process cost. An example was presented for the separation of CH4/N2 mixtures in coal bed methane (CBM) treatment. The key operation parameters were also studied and they showed the influence to process configurations. 展开更多
关键词 coal bed methane gas separation DESIGN MODULES OPTIMIZATION
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A Non-linear Non-ideal Model of Simulated Moving Bed Chromatography for Chiral Separations 被引量:8
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作者 卢建刚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期234-239,共6页
A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of... A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of simulated moving bed chromatography (SMBC). The model equations were solved by a new efficient numerical technique of orthogonal collocation on finite elements with periodical movement of concentration vector. The simulated SMBC performance is in accordance with the experimental results reported in the literature for separation of l,1'-bi-2-naphthol enantiomers using SMBC. This model is useful for design, operation, optimization and scale-up of non-linear SMBC for chiral separations with significant non-ideal effects, especially for high solute concentration and small intraparticle diffusion coefficient or large chiral stationary phase particle. 展开更多
关键词 simulated moving bed chromatography chiral separation non-linear isotherm non-ideal effect DYNAMICS
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Prediction of upper limit position of bedding separation overlying a coal roadway within an extra-thick coal seam 被引量:5
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作者 YAN Hong ZHANG Ji-xiong +2 位作者 LI Lin-yue FENG Rui-min LI Tian-tong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期448-460,共13页
Failure of the surrounding rock around a roadway induced by roof separation is one major type of underground roof-fall accidents.This failure can especially be commonly-seen in a bottom-driven roadway within an extra-... Failure of the surrounding rock around a roadway induced by roof separation is one major type of underground roof-fall accidents.This failure can especially be commonly-seen in a bottom-driven roadway within an extra-thick coal seam("bottom-driven roadway"is used throughout for ease of reference),containing weak partings in their roof coal seams.To determine the upper limit position of the roof interlayer separation is the primary premise for roof control.In this study,a mechanical model for predicting the interlayer separation overlying a bottom-driven roadway within an extra-thick coal seam was established and used to deduce the vertical stress,and length,of the elastic,and plastic zones in the rock strata above the wall of the roadway as well as the formulae for calculating the deflection in different regions of rock strata under bearing stress.Also,an approach was proposed,calculating the stratum load,deflection,and limiting span of the upper limit position of the interlayer separation in a thick coal seam.Based on the key strata control theory and its influence of bedding separation,a set of methods judging the upper limit position of the roof interlayer separation were constructed.In addition,the theoretical prediction and field monitoring for the upper limit position of interlayer separation were conducted in a typical roadway.The results obtained by these two methods are consistent,indicating that the methods proposed are conducive to improving roof control in a thick coal seam. 展开更多
关键词 extra-thick coal seam bedding separation coal roadway roof fall mechanical model
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CFD-DEM simulation of fluid-solid flow of a tapered column separation bed 被引量:4
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作者 Duan Chenlong Sheng Cheng +2 位作者 Wu Lingling Zhao Yuemin He Jinfeng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期855-859,共5页
Research on recycling waste Printed Circuit Boards(PCB) is at the forefront of preventing environmental pollution and finding ways to recycle resources.The Tapered Column Separation Bed(TCSB) is invented aiming at dis... Research on recycling waste Printed Circuit Boards(PCB) is at the forefront of preventing environmental pollution and finding ways to recycle resources.The Tapered Column Separation Bed(TCSB) is invented aiming at disposing the problem that fine particles of waste printed circuit boards cannot be separated efficiently so as to obtain further insight about the underlying mechanisms and demonstrate the separation feasibility in the tapered column separation bed.In this work,a Computational Fluid Dynamics(CFD) coupled with Discrete Element Method(DEM) model for two-phase flow has been extended to simulate the fluid-solid flow in the tapered column separation bed.Its validity is demonstrated by its successful capturing the key features of particles' flow pattern,velocity,the pressure distribution,the axial position with time and axial force for particles with different densities.Simulation results show that the plastic particles and resin particles become overflow,while copper particles,iron particles and aluminum particles successively become underflow,with a discharge water flow rate of 1 m^3/h,an obliquity of 30°.The simulated results agree reasonably well with the experimental observation.Using this equipment to separate waste PCBs is feasible,theoretically. 展开更多
关键词 Tapered column separation bed Waste printed circuit boards Computational fluid dynamics Discrete element method Fluid-solid flow
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Effect of bubbles addition on teetered bed separation 被引量:2
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作者 Ni Chao Xie Guangyuan +3 位作者 Liu Bo Bu Xiangning Peng Yaoli Sha Jie 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期835-841,共7页
To improve the separation efficiency of a conventional Teetered Bed Separator(TBS) in beneficiation of fine coal with a wide size range,an Aeration TBS(A-TBS) was proposed in this investigation.The bubbles were introd... To improve the separation efficiency of a conventional Teetered Bed Separator(TBS) in beneficiation of fine coal with a wide size range,an Aeration TBS(A-TBS) was proposed in this investigation.The bubbles were introduced to A-TBS by a self-priming micro-bubble generator.This study theoretically analyzed the effect of bubbles on the difference in hindered settling terminal velocity between different density particles,investigated the impact of superficial water velocity(V_(SW)) and superficial gas velocity(V_(Sg)) on bed fluidization,and compared the performance of the TBS and A-TBS in treating 1-0.25 mm size fraction particles.The results show that the expansion degree of fluidized bed which was formed by different size particles or has different initial height,is increased by the introduction of bubbles.Compared with the TBS,at the same level of clean coal ash content,the A-TBS shows an increase in the combustible recovery of clean coal,ash content of tailings,and practical separation density by 5.26%,6.56%,and 0.088 g/cm3 respectively,while it shows a decrease in the probable error(E_p) and V_(SW) by 0.031 and 3.51 mm/s,respectively.The addition of bubbles at a proper amount not only improves the separation performance of TBS,but also reduces the upward water velocity. 展开更多
关键词 Teetered bed separator Fine coal BUBBLES Superficial water velocity Superficial gas velocity
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Separation of phosphatidylcholine from soybean phospholipids by simulated moving bed 被引量:1
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作者 LU Yu-bint YANG Yi-wen WU Ping-dong 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第7期559-564,共6页
A simulated moving bed (SMB), equipped with eight silica-gel columns, was used to separate phosphatidylcholine (PC) from soybean phospholipids. The effects of flow rate in Sections 2 (Q2) and 3 (Q3), switching time, f... A simulated moving bed (SMB), equipped with eight silica-gel columns, was used to separate phosphatidylcholine (PC) from soybean phospholipids. The effects of flow rate in Sections 2 (Q2) and 3 (Q3), switching time, feed flow rate and feed concentration on the operating performance parameters: purity, recovery, productivity and desorbent consumption were studied. Operating conditions leading to more than 90% purity in both outlet streams have been identified, together with those achieving optimal performance. Regions leading to complete separation are observed and explained theoretically. As the mass-transfer effect was not considered, the triangle theory only gives initial guesses for the optimal operating conditions. 展开更多
关键词 Simulated moving bed (SMB) separation Soybean phosphatidylcholine (PC)
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Equivalent materials simulation experimental study on bed separations developing and mining subsidence in constant humidity and constant temperature conditions
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作者 付志亮 王素华 高延法 《Journal of Coal Science & Engineering(China)》 2008年第4期585-590,共6页
A new experiment was made on the developing of bed separations and mining subsidence from Tangshan T2192 working face by equivalent materials simulation.The overburden deformation and the developing of bed separations... A new experiment was made on the developing of bed separations and mining subsidence from Tangshan T2192 working face by equivalent materials simulation.The overburden deformation and the developing of bed separations with working face advanc- ing was simulated by a new model.The results show that the maximum value of bed separations moved forward gradually along with the working face advancing;the maxi- mum value of bed separations is 0.31~0.50 times of mining thickness.The key strata have a great influence upon surface subsidence during the overburden movement process.The mechanics parameters of new experiment are fitted with results in fields perfectly. 展开更多
关键词 SUBSIDENCE bed separations constant humidity constant temperature equivalent simulation experiment
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Mechanics Principle and Engineering Application of Split Layer and Bed Separation of Mining Overburden
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作者 YU Guang-ming ZHANG Chun-hui +3 位作者 SU Zhong-jie FAN Xue-li PAN Yong-zhan LIU Fu-shun 《地球与环境》 CAS CSCD 北大核心 2005年第B10期17-26,共10页
To control land surface subsidence caused the underground mineral exploitation and the catastrophic phenomena such as serious damage of buildings, waterbodies, cultivated lands, railways, bridges caused by land subsid... To control land surface subsidence caused the underground mineral exploitation and the catastrophic phenomena such as serious damage of buildings, waterbodies, cultivated lands, railways, bridges caused by land subsidence, bed separation grouting technology of overburden is put forward. To provide theoretical support for the technology, the characteristics and the mechanics mechanism of mining overburden from layer-split to formation of bed separation are studied. On the basis of elastic sheet board theory, calculation formula of rock sheet deflection is presented, and the mechanics criteria of the separation formation and the calculation formula of bed separation volume are set up. Finally, the applications and technics of bed separation grout technology of mining overburden to control land subsidence in china are introduced. 展开更多
关键词 矿井 承载力 岩石力学 岩层沉陷 偏斜现象
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Fluidization stability and periodic fluctuations in gas–solid separation fluidized bed using Geldart A dense medium
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作者 Weijin Liu Dan Wang +4 位作者 Liang Dong Enhui Zhou Tatiana Aleksandrova Chenyang Zhou Chenlong Duan 《Particuology》 SCIE EI CAS CSCD 2024年第7期522-534,共13页
Gas–solid separation fluidized bed is a typical method for coal separation without water utilization.Geldart A particles is also considered as the ideal dense medium to strengthen separation efficiency.Fluidization s... Gas–solid separation fluidized bed is a typical method for coal separation without water utilization.Geldart A particles is also considered as the ideal dense medium to strengthen separation efficiency.Fluidization stability reflects the bed pressure fluctuations and the distribution of bubble and emulsion phases,affecting the separation performance.And the main frequency of pressure fluctuations can directly reflect the degree of pressure fluctuations.Therefore,the detailed fluidization stability is analyzed combined the method of standard deviation of pressure fluctuations,power spectral density,etc.,for Geldart A particles.The results showed that maintaining an appropriate gas velocity resulted in an average bed pressure of around 2000 Pa.The main frequency is mainly concentrated around 1–1.5 Hz.Finally,a prediction model of the main frequency of pressure fluctuations is established,and the error can be controlled within±0.15.The investigation further proved the stable fluidization of Geldart A particles and provides a method for predicting the main frequency of pressure fluctuations in the gas–solid separation fluidized bed. 展开更多
关键词 Geldart A dense medium Fluidization stability Periodic fluctuations Pressure fluctuations frequency Gas–solid separation fluidized bed
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Comparison of coal separation characteristics based on different separating approaches in dry coal beneficiation flowsheet 被引量:2
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作者 贺靖峰 赵跃民 +2 位作者 何亚群 骆振福 段晨龙 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1651-1659,共9页
The separation characteristic of raw coal from Luoyang mining area, China, was investigated by applying a dry coal beneficiation flowsheet with the dense medium gas-solid fluidized bed as main separating equipment. Th... The separation characteristic of raw coal from Luoyang mining area, China, was investigated by applying a dry coal beneficiation flowsheet with the dense medium gas-solid fluidized bed as main separating equipment. The experimental and simulation results indicate that the dense medium gas-solid fluidized bed can provide uniform distribution and stable fluctuation of bed densities at various heights. Two types of different separating approaches were compared using the dry coal beneficiation flowsheet. Compared with obtaining cleaning coal in the first stage of the flowsheet, a higher yield of the cleaning coal and better separation efficiency can be achieved when discharging gangue in the first stage. Finally, the results indicate that 64.86% pure cleaning coal with an ash content of 11.77% and 13.53% middlings were obtained, and 21.61% gangue was removed in two successive separation stages with the probable errors of 0.05 and 0.07 g/cm3, respectively. 展开更多
关键词 separation characteristic dense medium gas-solid fluidized bed separating approach numerical simulation density stability
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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 被引量:7
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作者 Wan Chen Xiaonan Guo +10 位作者 Enbao Zou Mengling Luo Mengzijing Chen Mingke Yang Hai Li Chongzhi Jia Chun Deng Changyu Sun Bei Liu Lanying Yang Guangjin Chen 《Green Energy & Environment》 SCIE CSCD 2020年第3期347-363,共17页
Coal bed methane has been considered as an important energy resource.One major difficulty of purifying coal bed methane comes from the similar physical properties of CH_4 and N_2.The ZIF-8/water-glycol slurry was used... Coal bed methane has been considered as an important energy resource.One major difficulty of purifying coal bed methane comes from the similar physical properties of CH_4 and N_2.The ZIF-8/water-glycol slurry was used as a medium to separate coal bed methane by fluidifying the solid adsorbent material.The sorption equilibrium experiment of binary mixture(CH_4/N_2)and slurry was conducted.The selectivity of CH_4 to N_2 is within the range of 2-6,which proved the feasibility of the slurry separation method.The 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 developed.Sensitivity analysis is conducted to determine the operation conditions and the energy performance of the proposed process was also evaluated.Feed 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. 展开更多
关键词 Coal bed methane Gas separation Phase equilibrium experiment Mathematical model Process simulation
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Recovering metals from printed circuit board scrap by a mechanical separation process
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作者 徐敏 李光明 《Journal of Chongqing University》 CAS 2008年第2期100-106,共7页
A mechanical separation process was developed for recovering metals from printed circuit board(PCB) scrap;it included three steps:impact crushing,sieving and fluidization separation.The mechanism of the technique was ... A mechanical separation process was developed for recovering metals from printed circuit board(PCB) scrap;it included three steps:impact crushing,sieving and fluidization separation.The mechanism of the technique was based on the difference in the crushabilities of metallic and nonmetallic materials in the PCBs that led to the concentrated distribution of metals in particles of larger sizes and nonmetals mostly in particles of smaller sizes.It was found that crushed PCB particles from 0.125 mm to 1.000 mm contained about 80% of metals in the PCBs.Metals acquired satisfactory liberation in particles smaller than 0.800 mm.The crushed PCB particles were sieved into fractions of different size ranges.Each fraction separately went through a gas-solid fluidized bed operating at a selected optimal gas velocity for the specific size range.Approximately 95% of metals in printed circuit board particles from 0.125 mm to 0.800 mm was recovered by the gas-fluidized bed separator at the selected optimal gas velocity.However,separation of metals from particles smaller than 0.125 mm was not satisfactory.Further study is needed on metal recovery from fine particles. 展开更多
关键词 metal recovery fluidized bed printed circuit board scrap mechanical recycling fluidization separation
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陕西省煤矿典型水灾隐患特征及治理技术 被引量:4
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作者 董书宁 樊敏 +5 位作者 郭小铭 刘英锋 郭康 姬中奎 李超峰 薛小渊 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期902-916,共15页
陕西省煤炭资源丰富,2022年煤炭产量达7.46亿t,是我国主要产煤省份之一。由于全省煤矿区地质及水文地质条件差异明显,煤矿水灾类型多样,随着近年煤炭开采强度的增大,水灾事故时有发生,防治水形势较为严峻。以煤炭赋存条件为基础,系统总... 陕西省煤炭资源丰富,2022年煤炭产量达7.46亿t,是我国主要产煤省份之一。由于全省煤矿区地质及水文地质条件差异明显,煤矿水灾类型多样,随着近年煤炭开采强度的增大,水灾事故时有发生,防治水形势较为严峻。以煤炭赋存条件为基础,系统总结区域水文地质结构特征,界定典型水灾类型及各类水灾影响区域分布,论述典型水灾的形成机理及特征,并提出了相应的防控技术。研究表明:(1)陕西省主要煤炭产区分为陕北、黄陇、渭北三大区,陕北侏罗纪煤田主要有顶板松散沙层水灾隐患、厚层砂岩水灾隐患、溃水溃沙灾害,局部区域分布有烧变岩对煤矿造成水灾隐患;黄陇煤田主要受顶板巨厚砂岩水灾隐患、离层溃水隐患、泥砂溃涌灾害隐患威胁;陕北石炭—二叠纪煤田和渭北煤田,主要受到煤层底板奥陶系灰岩水灾隐患威胁。(2)陕北侏罗系煤田顶板水灾隐患主要为顶板含水层受开采导水裂隙带扰动形成,导水裂隙波及砂岩含水层或松散沙层可形成持续大流量涌水,部分区域充水强度较大,在短时间水量较大超过排水系统能力时造成顶板水灾,在薄基岩区域垮落带直接导通松散沙层时可转变为溃水溃沙灾害,导水裂隙带影响到烧变岩富水区域时可形成瞬时水量大且持续的烧变岩水灾;黄陇煤田顶板巨厚砂岩含水层受采动导水裂隙带波及形成高强度持续涌水并可能形成顶板水灾,当含水层下部隔水层厚度较大时,可能形成离层溃水灾害,当近煤层顶板岩层松软遇水易崩解时可转变为泥砂溃涌灾害;陕北石炭—二叠纪煤田和渭北煤田,煤层开采底板扰动破坏带或断层等构造导通奥陶系灰岩含水层时,会引发极为严重的底板突水灾害,该类灾害具突发性强、瞬时水量大的特征。(3)各区域的顶板水灾隐患治理技术主要包括钻孔疏泄、注浆治理、开采参数控制等,底板水灾隐患治理技术主要包括区域注浆加固及封堵等;烧变岩水灾隐患主要采取帷幕注浆与钻孔探放有机结合的防治技术。 展开更多
关键词 陕西省煤矿 溃水溃沙 烧变岩水灾 离层溃水 泥砂溃涌 底板奥灰水灾
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湿法磁选对粉煤灰中铁和重金属元素的分布影响研究
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作者 李快 栗照帅 +3 位作者 董庭轩 李丹 郭生伟 韩凤兰 《无机盐工业》 CAS CSCD 北大核心 2024年第4期98-104,150,共8页
对煤粉锅炉粉煤灰(FA1灰)和循环流化床锅炉粉煤灰(FA2灰)采用湿法磁选的工艺达到降低其重金属含量的目的。利用扫描电子显微镜、激光粒度仪和X射线衍射仪表征两种粉煤灰在不同磁感应强度和不同磁选溶液浓度条件下磁选前后高磁性和弱磁... 对煤粉锅炉粉煤灰(FA1灰)和循环流化床锅炉粉煤灰(FA2灰)采用湿法磁选的工艺达到降低其重金属含量的目的。利用扫描电子显微镜、激光粒度仪和X射线衍射仪表征两种粉煤灰在不同磁感应强度和不同磁选溶液浓度条件下磁选前后高磁性和弱磁性部分的形貌、粒度分布和物相分析,同时测定其铁元素和5种重金属元素(Hg、Pb、As、Cr、Cd)的含量变化,发现磁选后两种粉煤灰铁回收率随着磁感应强度增强而逐渐增加,高磁性组中重金属元素含量与弱磁性组有明显差异。结果表明:在磁感应强度为8000 Gs和磁选溶液浓度为20%(质量分数)时,FA1的铁回收率为71.2%,FA2的铁回收率为47.0%。此时FA1磁选后Pb含量差值为0.2 mg/kg、Cr含量差值为9.2 mg/kg、As含量差值为1.1 mg/kg;FA2磁选后Pb含量差值为18.1 mg/kg、Cr含量差值为25.0 mg/kg、As含量差值为9.1 mg/kg。 展开更多
关键词 磁选 粉煤灰 重金属元素 循环流化床
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新型细粒级加重质矿物气固分选流态化密度分布研究
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作者 孙郡庆 沈繁舜 +5 位作者 李林海 李泽鑫 李子源 周晨阳 周恩会 张亚东 《中国煤炭》 北大核心 2024年第9期111-119,共9页
煤炭分选对提升煤炭品质具有重要作用,气固流化床选煤将流态化技术应用于选煤领域,有助于实现煤炭的干法提质。为解决传统Geldart B类加重质流态化分选密度波动大的难题,提出采用Geldart A类细粒级加重质用于流态化分选的思路。系统研... 煤炭分选对提升煤炭品质具有重要作用,气固流化床选煤将流态化技术应用于选煤领域,有助于实现煤炭的干法提质。为解决传统Geldart B类加重质流态化分选密度波动大的难题,提出采用Geldart A类细粒级加重质用于流态化分选的思路。系统研究了新型细粒级加重质气固流态化分选床层密度分布特征,探究了床层密度的稳定性和细粒煤分选效果,分析了床层密度方差和分选效率的变化规律。结果表明,细粒级加重质中的床层密度分布更为均匀,轴向密度差异较低;结合床层膨胀行为研究,建立了细粒级加重质流化床床层密度预测模型,密度波动处于±0.1 g/cm 3时可以有效预测床层密度的分布,解决了分选过程中密度调控的难题。 展开更多
关键词 干法分选 流化床 密度分布 密度预测 加重质
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径向流氦氢分离床穿透特性实验与模拟分析
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作者 丁卫东 占勤 +1 位作者 杨洪广 连旭东 《原子能科学技术》 EI CSCD 北大核心 2024年第1期181-188,共8页
为系统深入研究径向流氦氢分离床的吸附穿透性能,指导结构设计,本研究借助COMSOL Multiphysics软件耦合材料吸氢动力学方程、流体流动动量方程和质量传递方程,建立了径向床穿透数学模型,并结合实验验证了模型的可靠性,利用模型对特性参... 为系统深入研究径向流氦氢分离床的吸附穿透性能,指导结构设计,本研究借助COMSOL Multiphysics软件耦合材料吸氢动力学方程、流体流动动量方程和质量传递方程,建立了径向床穿透数学模型,并结合实验验证了模型的可靠性,利用模型对特性参数进行参数化扫描,分析其对穿透性能的影响。结果表明,穿透实验结果与模拟数据符合较好,模型可靠。通过分析温度、高径比及孔隙率等参数对床体穿透性能的影响,推荐氦氢分离床床体参数如下:床体吸附温度为室温~343 K,在该温度范围内升高温度对传质区长度及出口处浓度-时间曲线影响较小;随着高径比的增加,床体效率明显下降,其中高径比为2.00~8.33时,维持高效率的时间较长;随着孔隙率的增加,床体吸附效率明显下降,考虑床层的吸附效率、压阻效应及粉末的装填难度,粉末孔隙率推荐0.56~0.64。以上结果表明,本研究建立的模型可较好地预测床体的吸附分离性能,可用于床体结构设计以及工艺参数的优化。 展开更多
关键词 径向流 氦氢分离床 穿透特性 数值模拟
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气-固脉动流化床加重质混合与分离特性及煤炭分选研究
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作者 孙郡庆 沈繁舜 +5 位作者 李林海 李泽鑫 李子源 周晨阳 周恩会 张亚东 《煤炭技术》 CAS 2024年第10期269-273,共5页
煤炭是世界的主要能源,细粒煤的高效洁净利用已成为热点之一。试验采用以磁铁矿粉为主要加重质,与石英砂组成的二元加重质进行混合与分离的行为进行理论与试验分析。研究结果表明,0.25~0.15 mm石英砂与0.074~0.15 mm磁铁矿粉组成的二元... 煤炭是世界的主要能源,细粒煤的高效洁净利用已成为热点之一。试验采用以磁铁矿粉为主要加重质,与石英砂组成的二元加重质进行混合与分离的行为进行理论与试验分析。研究结果表明,0.25~0.15 mm石英砂与0.074~0.15 mm磁铁矿粉组成的二元加重质颗粒在在脉动流化床中整体上分布均匀稳定,离析程度较低,分选密度的宏观调控范围可以达到1.30~1.90 g/cm^(3),保证脉动流化床中密度在较大范围内的调节,符合工业生产的要求。6~3 mm细粒煤的低密度分选试验结果表明,当脉动气流控制在频率流化数N=1.3,f=2.55 Hz时,精煤灰分值为4.47%,此时可能偏差为E=0.11 g/cm^(3),分选效果理想。 展开更多
关键词 脉动流化床 二元加重质 煤炭干法分选
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顺序式模拟移动床色谱高效纯化低聚异麦芽糖应用研究
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作者 阮圣慧 郑喜群 +2 位作者 刘晓兰 李良玉 姜彩霞 《食品与机械》 CSCD 北大核心 2024年第7期163-168,230,共7页
[目的]提高低聚糖行业的生产效率。[方法]以50型低聚异麦芽糖浆为原料,利用顺式模拟移动床色谱分离技术对其纯化。通过制备色谱单柱试验筛选出钾离子型树脂为合适的分离介质;根据物料平衡原理和顺序式模拟移动床基本原理近似确定分离工... [目的]提高低聚糖行业的生产效率。[方法]以50型低聚异麦芽糖浆为原料,利用顺式模拟移动床色谱分离技术对其纯化。通过制备色谱单柱试验筛选出钾离子型树脂为合适的分离介质;根据物料平衡原理和顺序式模拟移动床基本原理近似确定分离工艺的初始操作参数,并对分离条件进行优化。[结果]最佳技术参数为:料液折光率60%、柱温65℃、进样量455 mL、进水量682 mL、进样流量37.4 mL/min、进水流量29.6 mL/min以及总循环流量364 mL/h,在此条件下低聚异麦芽糖出口折光为20.40%,纯度达到90.20%,收率达到85.50%。[结论]自主研制的顺序式模拟移动床色谱分离设备可用于高效纯化低聚异麦芽糖。 展开更多
关键词 顺序式模拟移动床 色谱分离 纯化 低聚异麦芽糖
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我国不同类别煤层顶板水害致灾机理与防控路径 被引量:4
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作者 曾一凡 朱慧聪 +6 位作者 武强 王皓 郭小铭 崔芳鹏 庞振忠 刘守强 杨维弘 《煤炭学报》 EI CAS CSCD 北大核心 2024年第3期1539-1555,共17页
我国是世界上成煤和赋存条件最复杂的国家,煤层顶板水文地质条件的多样性和复杂性,采动覆岩裂隙场与渗流场耦合的相互性和时变性以及煤层顶板突水的独特性和危害性,造成顶板水害是我国尤其是西部煤矿区的主要矿井灾害之一。为了更好地... 我国是世界上成煤和赋存条件最复杂的国家,煤层顶板水文地质条件的多样性和复杂性,采动覆岩裂隙场与渗流场耦合的相互性和时变性以及煤层顶板突水的独特性和危害性,造成顶板水害是我国尤其是西部煤矿区的主要矿井灾害之一。为了更好地认识顶板水害和推广现有技术和探索新技术防控此类矿井灾害,在全面分析近年来我国煤层顶板水害事故规律与顶板充水含水层的赋存条件、突水模式、动力特征、力学行为等基础上,系统划分了顶板水害的类型、特征、主要类别的致灾机理及梳理了现有顶板水害的防治技术,并展望了未来顶板水害防治领域的发展方向。研究发现:①顶板水害主体架构包括巨厚基岩含水层涌(淋)水、薄基岩弱胶结层水-砂耦合溃涌、离层空间蓄水储能突水、天窗补给型突水、围岩烧变增透致突等5种类别,集中分布于秦岭—淮河沿线以北地区,陕、蒙、宁是顶板水害主要聚集地。②采动诱发巨厚基岩含水层下覆岩原生裂隙互馈-贯通发育“Z”型离层空间,导致采场出现大面积涌(淋)水现象;基于复合关键层破断力学条件,阐明了薄基岩弱胶结层水-砂耦合溃涌致灾的动力源;构建了离层失稳突水临界判别准则,将离层突水划分为静载扰动、“动+静”载复合扰动、复合煤层开采重复扰动3种模式;红土隔水层缺失及红土薄弱区采动劣化损伤是产生天窗越流补给的主要根源;围岩烧变增透,孔隙度增大,接受临近水源补水后形成新的含水结构体,在采动诱发下烧变岩水涌入采场发生水害事故。③梳理了当前煤层顶板水害“探-放-治”三位一体的解危防控技术体系,提出了井上下共轭联动、钻-采(掘)高位协同地质勘探系统,以防治水“三区”划分为导向的地质保障工作,“煤-水-生态”多目标齐抓共管的绿色开采和防治水理念,以及数智化、透明化矿山水文地质灾害信息维护系统等未来发展方向。 展开更多
关键词 顶板水害 矿井防治水 离层突水 致灾机理 防控技术
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分子筛吸附剂对不同类型柴油吸附分离性能的研究 被引量:1
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作者 赵闯 陈自浩 +5 位作者 张博宇 李犇 靳凤英 李滨 孙振海 郭春垒 《无机盐工业》 CAS CSCD 北大核心 2024年第3期80-85,共6页
采用离子交换法制备分子筛吸附剂,分析发现分子筛吸附剂的孔结构以晶内微孔为主,并含有晶间介孔,具有结晶度高、晶粒分布均匀、弱酸和强酸协同作用的特点。以不同类型柴油为吸附原料和轻型解吸剂(沸点低于柴油),利用模拟移动床分离装置... 采用离子交换法制备分子筛吸附剂,分析发现分子筛吸附剂的孔结构以晶内微孔为主,并含有晶间介孔,具有结晶度高、晶粒分布均匀、弱酸和强酸协同作用的特点。以不同类型柴油为吸附原料和轻型解吸剂(沸点低于柴油),利用模拟移动床分离装置,考察分子筛吸附剂对不同类型柴油的吸附分离性能。结果显示:在吸附温度为120℃、压力为1.2 MPa、吸附区回流比为0.5~1.5、精制区回流比为0.2~1.5、解吸区回流比为2.0~6.0、隔离区回流比-2~0的条件下,分子筛吸附剂在不同类型柴油吸附-脱附体系下运行稳定,芳烃产品中芳烃纯度>95%,非芳烃产品中非芳烃纯度>95%;不同类型柴油中硫氮含量、馏程轻重和芳烃含量对吸附分离效果没有影响,不同类型柴油中芳烃含量越高,解吸剂与柴油体积比越高,在模拟工业应用条件下,分子筛吸附剂稳定运行时间超过600 d,所制得的分子筛吸附剂具有芳烃选择性高、吸附容量大、运行稳定性高等特点。 展开更多
关键词 柴油 分子筛吸附剂 解吸剂 模拟移动床 吸附分离
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