CAJ | 학술논문

沉积物与流体流动的性质是影响水合物形成和聚集的两个重要因素,为研究水合物在沉积地层中的赋存机制必须探明高压环境下含水合物沉积物在非饱和渗流条件下的相互影响关系.以逸度差为水合物反应驱动力,反应动力学常数为Arrhenius 类型,建立了包括非饱和流体流动-沉积物特征-水合物形成动力学耦合的二维模型,从理论上研究了多孔介质内流体与沉积物参数如含水率、去饱和系数、水力分布和水合物饱和度等在孔隙内的相互影响规律.结果表明,在设定的条件下,随着反应的进行孔隙水压力随时间逐渐大,在相同条件下水合物饱和度与温度增加导致孔隙水压力变大,其中水合物饱和度的影响较小,而沉积物基质吸力、去饱和系数与本征动力学常数则与孔隙水压力成反向变化,其中本征动力学常数的影响较大.
침적물여류체류동적성질시영향수합물형성화취집적량개중요인소,위연구수합물재침적지층중적부존궤제필수탐명고압배경하함수합물침적물재비포화삼류조건하적상호영향관계.이일도차위수합물반응구동력,반응동역학상수위Arrhenius 류형,건립료포괄비포화류체류동-침적물특정-수합물형성동역학우합적이유모형,종이론상연구료다공개질내류체여침적물삼수여함수솔、거포화계수、수력분포화수합물포화도등재공극내적상호영향규률.결과표명,재설정적조건하,수착반응적진행공극수압력수시간축점대,재상동조건하수합물포화도여온도증가도치공극수압력변대,기중수합물포화도적영향교소,이침적물기질흡력、거포화계수여본정동역학상수칙여공극수압력성반향변화,기중본정동역학상수적영향교대.
Sediments and fluids characteristics are the two important factors affected the formation and accumulation of methane hydrate in deposits. In order to study methane hydrate occurrence in sediments, the influences of unsaturated fluids on hydrate-bearing sedimentary strata under high-pressure seepage environment must be discussed. The difference of fugacity has been adopted to be the driving force in this reaction. The hydrate intrinsic kinetic constant has been written in an Arrhenius-type equation. A two-dimensional (horizontal, vertical) model coupling the aspects of unsaturated flow fluids-sedimentary characteristics-hydrate formation kinetics has been established. The evolution of porous hydraulic parameters such as water content, to-saturation coefficient, pore water pressure and hydrate saturation have been discussed. Under the conditions setting in the simulation, the results show that the pore water pressure becomes larger with time during the reaction proceeding. Under the same conditions, the increase of strata temperature and hydrate saturation will increase the pore water pressure. The hydrate saturation causes less influence; while the sediments matric suction, to-saturation coefficient and hydrate intrinsic kinetic constant will vary inversely with the pore water pressure;and the to-saturation coefficient has more strong effects.