中国矿业
中國礦業
중국광업
CHINA MINING MAGAZINE
2014年
12期
124-127
,共4页
页岩%等温吸附%压力%引斥力%吸附异常
頁巖%等溫吸附%壓力%引斥力%吸附異常
혈암%등온흡부%압력%인척력%흡부이상
shale%isotherm%pressure%gravitation and repulsion%adsorption abnormal
从分子学角度出发，探讨了页岩吸附量随压力变化趋势可能的内在原因。并结合模拟实验数据，分析了页岩在吸附后期出现吸附异常现象的原因。研究认为，甲烷分子在页岩表面的吸附与分子间引斥力的相互作用密切相关。在吸附初期，页岩表面能相对较大，甲烷分子和页岩表面分子间作用力以吸引力为主且逐渐增大，页岩吸附量随压力升高而增大且增加较快；在吸附中期，页岩表面能减小，甲烷分子和页岩表面分子间作用力由吸引力向排斥力转变，页岩吸附量随压力升高增加变缓达到最大值，此时吸附速率与解吸速率动态平衡；在吸附后期的超高压下，页岩表面能趋于零，甲烷分子和页岩表面分子间作用力以排斥力为主且增加较快，页岩吸附量随压力的升高而降低，甚至出现负值。页岩吸附异常的原因主要有两点：一是页岩具有相对低的吸附量，而且甲烷分子直径大于氦气，致使实验所用自由体积值偏大，造成计算结果“负吸附”；二是高压下页岩中甲烷处于超临界吸附且具有较大的分子间斥力。
從分子學角度齣髮，探討瞭頁巖吸附量隨壓力變化趨勢可能的內在原因。併結閤模擬實驗數據，分析瞭頁巖在吸附後期齣現吸附異常現象的原因。研究認為，甲烷分子在頁巖錶麵的吸附與分子間引斥力的相互作用密切相關。在吸附初期，頁巖錶麵能相對較大，甲烷分子和頁巖錶麵分子間作用力以吸引力為主且逐漸增大，頁巖吸附量隨壓力升高而增大且增加較快；在吸附中期，頁巖錶麵能減小，甲烷分子和頁巖錶麵分子間作用力由吸引力嚮排斥力轉變，頁巖吸附量隨壓力升高增加變緩達到最大值，此時吸附速率與解吸速率動態平衡；在吸附後期的超高壓下，頁巖錶麵能趨于零，甲烷分子和頁巖錶麵分子間作用力以排斥力為主且增加較快，頁巖吸附量隨壓力的升高而降低，甚至齣現負值。頁巖吸附異常的原因主要有兩點：一是頁巖具有相對低的吸附量，而且甲烷分子直徑大于氦氣，緻使實驗所用自由體積值偏大，造成計算結果“負吸附”；二是高壓下頁巖中甲烷處于超臨界吸附且具有較大的分子間斥力。
종분자학각도출발，탐토료혈암흡부량수압력변화추세가능적내재원인。병결합모의실험수거，분석료혈암재흡부후기출현흡부이상현상적원인。연구인위，갑완분자재혈암표면적흡부여분자간인척력적상호작용밀절상관。재흡부초기，혈암표면능상대교대，갑완분자화혈암표면분자간작용력이흡인력위주차축점증대，혈암흡부량수압력승고이증대차증가교쾌；재흡부중기，혈암표면능감소，갑완분자화혈암표면분자간작용력유흡인력향배척력전변，혈암흡부량수압력승고증가변완체도최대치，차시흡부속솔여해흡속솔동태평형；재흡부후기적초고압하，혈암표면능추우령，갑완분자화혈암표면분자간작용력이배척력위주차증가교쾌，혈암흡부량수압력적승고이강저，심지출현부치。혈암흡부이상적원인주요유량점：일시혈암구유상대저적흡부량，이차갑완분자직경대우양기，치사실험소용자유체적치편대，조성계산결과“부흡부”；이시고압하혈암중갑완처우초림계흡부차구유교대적분자간척력。
In view of molecular ,the possible internal cause of shale adsorption trend with pressure change was discussed .And according to simulation data ,the causes of shale adsorption abnormal in the late adsorption were analyzed .Results show that methane molecules adsorbed on the surface of the shale is closed related to the interaction of gravitation and repulsion between molecules .Early in the adsorption ,shale surface energy is relatively large ,the intermolecular force between methane molecules and shale surface molecules is gradually increasing gravitation ,which leads shale adsorption to increasing rapidly with pressure increasing .In the middle of adsorption ,shale surface energy decreases ,the intermolecular force between methane molecules and shale surface molecules transforms from gravitation to repulsion ,which leads shale adsorption to increasing slowly to maximum .At this point the adsorption rate and desorption rate are dynamic equilibrium .Under super high pressure in the adsorption late ,shale surface energy tends to zero ,the intermolecular force between methane molecules and shale surface molecules is rapidly increasing repulsion , which leads shale adsorption to decreasing with pressure increasing even negative .There are two main reasons for shale adsorption abnormal :First ,a relatively low shale adsorption and the greater methane molecular diameter than helium result in larger free volume value in the experiment ,which leads to the results of “negative absorption”;Second ,shale methane is in a supercritical adsorption under high pressure and intermolecular has larger repulsion .
