Based on the methodology for petroleum systems and through the anatomy and geochemical study of typical helium-rich gas fields,the geological conditions,genesis mechanisms,and accumulation patterns of helium resources...Based on the methodology for petroleum systems and through the anatomy and geochemical study of typical helium-rich gas fields,the geological conditions,genesis mechanisms,and accumulation patterns of helium resources in natural gas are investigated.Helium differs greatly from other natural gas resources in generation,migration,and accumulation.Helium is generated due to the slow alpha decay of basement U-/Th-rich elements or released from the deep crust and mantle,and then migrates along the composite transport system to natural gas reservoirs,where it accumulates with a suitable carrier gas.Helium migration and transport are controlled by the transport system consisting of lithospheric faults,basement faults,sedimentary layer faults,and effective transport layers.Based on the analysis of the helium-gas-water phase equilibrium in underground fluids and the phase-potential coupling,three occurrence states,i.e.water-soluble phase,gas-soluble phase and free phase,in the process of helium migration and accumulation,and three migration modes of helium,i.e.mass flow,seepage,and diffusion,are proposed.The formation and enrichment of helium-rich gas reservoirs are controlled by three major factors,i.e.high-quality helium source,high-efficiency transport and suitable carrier,and conform to three accumulation mechanisms,i.e.exsolution and convergence,buoyancy-driven,and differential pressure displacement.The helium-rich gas reservoirs discovered follow the distribution rule and accumulation pattern of near helium source,adjacent to fault,low potential area,and high position".To explore and evaluate helium-rich areas,it is necessary to conduct concurrent/parallel exploration of natural gas.The comprehensive evaluation and selection of profitable helium-rich areas with the characteristics of"source-trap connected,low fluid potential and high position,and proper natural gas volume matched with helium’s"should focus on the coupling and matching of the helium"source,migration,and accumulation elements"with the natural gas"source,reservoir and caprock conditions",and favorable carrier gas trap areas in local low fluid potential and high positions.展开更多
In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-p...In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-pressure core displacement experiments.Fine quantitative characterization of the cores in three steady states(original,after sulfur injection,and after gas flooding)was carried out using the nuclear magnetic resonance(NMR)transverse relaxation time spectrum and imaging,X-ray computer tomography(CT)of full-diameter cores,basic physical property testing,and field emission scanning electron microscopy imaging.The loss of pore volume caused by sulfur deposition and adsorption mainly comes from the medium and large pores with sizes bigger than 1000μm.Liquid sulfur has a stronger adsorption and deposition ability in smaller pore spaces,and causes greater damage to reservoirs with poor original pore structures.The pore structure of the three types of carbonate reservoirs shows multiple fractal characteristics.The worse the pore structure,the greater the change of internal pore distribution caused by liquid sulfur deposition and adsorption,and the stronger the heterogeneity.Liquid sulfur deposition and adsorption change the pore size distribution,pore connectivity,and heterogeneity of the rock,which further changes the physical properties of the reservoir.After sulfur injection and gas flooding,the permeability of TypeⅠreservoirs with good physical properties decreased by 16%,and that of TypesⅡandⅢreservoirs with poor physical properties decreased by 90%or more,suggesting an extremely high damage.This indicates that the worse the initial physical properties,the greater the damage of liquid sulfur deposition and adsorption.Liquid sulfur is adsorbed and deposited in different types of pore space in the forms of flocculence,cobweb,or retinitis,causing different changes in the pore structure and physical property of the reservoir.展开更多
The waste coffee-grounds carbon(WCGC)was prepared with H_(3)PO_(4)treated using waste coffee-grounds as precursor.Its adsorption ability was studied using phenol as test molecule.The influence of H_(3)PO_(4)treated,ca...The waste coffee-grounds carbon(WCGC)was prepared with H_(3)PO_(4)treated using waste coffee-grounds as precursor.Its adsorption ability was studied using phenol as test molecule.The influence of H_(3)PO_(4)treated,calcined temperature,the initial phenol concentration,the doge of carbon and original pH values on phenol adsorption ability were investigated.Characterization of WCGC was performed by N_(2)adsorption isotherms,Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),and X-ray diffraction(XRD)techniques.First,the second order and Weber-Morris model reaction rate models were used to estimate the WCGC adsorption ability.The results show that the produced WCGC(700℃,2 h)has been graphitized and the layered structure increased BET surface to 435.98 m^(2)/g and adsorption phenol ability.The initial phenol concentration is 50 mg/L,the amount of WCGC(700℃,2 h)is 0.2 g,and the phenol adsorption rate is 97%after 270 min and no intermediate product formation.The adsorption kinetics of the selected WCGC is best fitted by the Weber-Morris model.展开更多
以明胶水凝胶固化方法为辅助,采用激光诱导击穿光谱技术对Cr(NO3)3溶液中Cr元素进行了检测分析。实验研究了明胶水凝胶方法对比直采方式获得的Cr(NO3)3溶液中Cr元素特征谱线的增强效果,并选取Cr I 425.43nm作为分析线,通过研究Cr特征谱...以明胶水凝胶固化方法为辅助,采用激光诱导击穿光谱技术对Cr(NO3)3溶液中Cr元素进行了检测分析。实验研究了明胶水凝胶方法对比直采方式获得的Cr(NO3)3溶液中Cr元素特征谱线的增强效果,并选取Cr I 425.43nm作为分析线,通过研究Cr特征谱线信背比及背景信号强度随激光能量的变化关系,得到最佳激光能量140mJ。在最佳激光能量下建立Cr I 425.43nm的定标曲线,其线性相关指数R2为0.9994,检测限为1.05mg/L。研究结果表明,明胶水凝胶固化方法可以有效提高LIBS在水体中Cr元素的检测的灵敏度,改善检测限,且制样方法简单,未引入污染元素,为水体Cr元素检测提供了一种简单灵敏的方法。展开更多
基金Supported by the CNPC Technology Research Project(2021ZG13)。
文摘Based on the methodology for petroleum systems and through the anatomy and geochemical study of typical helium-rich gas fields,the geological conditions,genesis mechanisms,and accumulation patterns of helium resources in natural gas are investigated.Helium differs greatly from other natural gas resources in generation,migration,and accumulation.Helium is generated due to the slow alpha decay of basement U-/Th-rich elements or released from the deep crust and mantle,and then migrates along the composite transport system to natural gas reservoirs,where it accumulates with a suitable carrier gas.Helium migration and transport are controlled by the transport system consisting of lithospheric faults,basement faults,sedimentary layer faults,and effective transport layers.Based on the analysis of the helium-gas-water phase equilibrium in underground fluids and the phase-potential coupling,three occurrence states,i.e.water-soluble phase,gas-soluble phase and free phase,in the process of helium migration and accumulation,and three migration modes of helium,i.e.mass flow,seepage,and diffusion,are proposed.The formation and enrichment of helium-rich gas reservoirs are controlled by three major factors,i.e.high-quality helium source,high-efficiency transport and suitable carrier,and conform to three accumulation mechanisms,i.e.exsolution and convergence,buoyancy-driven,and differential pressure displacement.The helium-rich gas reservoirs discovered follow the distribution rule and accumulation pattern of near helium source,adjacent to fault,low potential area,and high position".To explore and evaluate helium-rich areas,it is necessary to conduct concurrent/parallel exploration of natural gas.The comprehensive evaluation and selection of profitable helium-rich areas with the characteristics of"source-trap connected,low fluid potential and high position,and proper natural gas volume matched with helium’s"should focus on the coupling and matching of the helium"source,migration,and accumulation elements"with the natural gas"source,reservoir and caprock conditions",and favorable carrier gas trap areas in local low fluid potential and high positions.
基金Supported by the National Natural Science Foundation of China(U19B6003)Sinopec Technology Research Project(P20077kxjgz)。
文摘In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-pressure core displacement experiments.Fine quantitative characterization of the cores in three steady states(original,after sulfur injection,and after gas flooding)was carried out using the nuclear magnetic resonance(NMR)transverse relaxation time spectrum and imaging,X-ray computer tomography(CT)of full-diameter cores,basic physical property testing,and field emission scanning electron microscopy imaging.The loss of pore volume caused by sulfur deposition and adsorption mainly comes from the medium and large pores with sizes bigger than 1000μm.Liquid sulfur has a stronger adsorption and deposition ability in smaller pore spaces,and causes greater damage to reservoirs with poor original pore structures.The pore structure of the three types of carbonate reservoirs shows multiple fractal characteristics.The worse the pore structure,the greater the change of internal pore distribution caused by liquid sulfur deposition and adsorption,and the stronger the heterogeneity.Liquid sulfur deposition and adsorption change the pore size distribution,pore connectivity,and heterogeneity of the rock,which further changes the physical properties of the reservoir.After sulfur injection and gas flooding,the permeability of TypeⅠreservoirs with good physical properties decreased by 16%,and that of TypesⅡandⅢreservoirs with poor physical properties decreased by 90%or more,suggesting an extremely high damage.This indicates that the worse the initial physical properties,the greater the damage of liquid sulfur deposition and adsorption.Liquid sulfur is adsorbed and deposited in different types of pore space in the forms of flocculence,cobweb,or retinitis,causing different changes in the pore structure and physical property of the reservoir.
基金Funded by Yunnan Provincial Agricultural Joint Project(No.2018FG001-051)Yunnan Provincial Department of Education Research Fund(No.2020Y0414)
文摘The waste coffee-grounds carbon(WCGC)was prepared with H_(3)PO_(4)treated using waste coffee-grounds as precursor.Its adsorption ability was studied using phenol as test molecule.The influence of H_(3)PO_(4)treated,calcined temperature,the initial phenol concentration,the doge of carbon and original pH values on phenol adsorption ability were investigated.Characterization of WCGC was performed by N_(2)adsorption isotherms,Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),and X-ray diffraction(XRD)techniques.First,the second order and Weber-Morris model reaction rate models were used to estimate the WCGC adsorption ability.The results show that the produced WCGC(700℃,2 h)has been graphitized and the layered structure increased BET surface to 435.98 m^(2)/g and adsorption phenol ability.The initial phenol concentration is 50 mg/L,the amount of WCGC(700℃,2 h)is 0.2 g,and the phenol adsorption rate is 97%after 270 min and no intermediate product formation.The adsorption kinetics of the selected WCGC is best fitted by the Weber-Morris model.
文摘以明胶水凝胶固化方法为辅助,采用激光诱导击穿光谱技术对Cr(NO3)3溶液中Cr元素进行了检测分析。实验研究了明胶水凝胶方法对比直采方式获得的Cr(NO3)3溶液中Cr元素特征谱线的增强效果,并选取Cr I 425.43nm作为分析线,通过研究Cr特征谱线信背比及背景信号强度随激光能量的变化关系,得到最佳激光能量140mJ。在最佳激光能量下建立Cr I 425.43nm的定标曲线,其线性相关指数R2为0.9994,检测限为1.05mg/L。研究结果表明,明胶水凝胶固化方法可以有效提高LIBS在水体中Cr元素的检测的灵敏度,改善检测限,且制样方法简单,未引入污染元素,为水体Cr元素检测提供了一种简单灵敏的方法。
