页岩气藏地质储量优化计算方法
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摘要
精确评价地质储量是页岩气藏开发规划的重要一步,虽然理论方法不断完善,但仍存在不足。在页岩气藏中,吸附气不仅包含甲烷,还存在一定比例的乙烷等其他烃类气体,应采用多组分吸附模型计算吸附气储量。同时,天然裂缝中大量存在的天然气也不能忽略。此外,干酪根中也溶解了一定的气体,忽略会导致较大误差。采用多组分吸附模型,考虑了吸附相占据的孔隙度、裂缝游离气及干酪根中的溶解气,建立了一种优化的页岩气藏地质储量计算模型。实例分析发现,裂缝游离气和溶解气占总储量的比例分别为10.41%和7.05%,传统方法计算得到的吸附气储量偏小,基质游离气储量偏大,总储量偏小。为了合理评价页岩气藏地质储量,应采用多组分吸附模型,考虑吸附相孔隙度且不能忽略裂缝游离气及干酪根中的溶解气。
Evaluating the gas in place accurately is one important part of the development planning of shale gas reservoirs, and its theories and methods are being improved continuously, but there are still some deficiencies. The adsorbed gas in shale gas reservoirs not only contains methane, but also a certain percentage of ethane and other hydrocarbon gases, so the adsorbed gas reserves shall be calculated by using the multi-component adsorption model. In addition, there is natural gas in a great number of natural fractures,which is not negligible. What's more, some gas is dissolved in the kerogen, and greater deviation will be induced if the dissolved gas is neglected. The multi-component adsorption model is used, the porosity occupied by the adsorbed phase, the free gas in fractures and the dissolved gas in kerogen are taken into account, and a modified calculation method for the gas in place of shale gas reservoirs is established. Case analysis indicates that the percentages of fracture free gas and dissolved gas in the total reserves are 10.41% and7.05%, respectively. The adsorbed gas reserves calculated by using the traditional method is lower, the matrix free gas reserves is higher and the total reserves is lower. In order to evaluate the gas in place of shale gas reservoirs rationally, it is necessary to adopt the multi-component adsorption model, and take into consideration the porosity of the adsorbed phase, as well as the free gas in fractures and the dissolved gas in kerogen.
Evaluating the gas in place accurately is one important part of the development planning of shale gas reservoirs, and its theories and methods are being improved continuously, but there are still some deficiencies. The adsorbed gas in shale gas reservoirs not only contains methane, but also a certain percentage of ethane and other hydrocarbon gases, so the adsorbed gas reserves shall be calculated by using the multi-component adsorption model. In addition, there is natural gas in a great number of natural fractures,which is not negligible. What's more, some gas is dissolved in the kerogen, and greater deviation will be induced if the dissolved gas is neglected. The multi-component adsorption model is used, the porosity occupied by the adsorbed phase, the free gas in fractures and the dissolved gas in kerogen are taken into account, and a modified calculation method for the gas in place of shale gas reservoirs is established. Case analysis indicates that the percentages of fracture free gas and dissolved gas in the total reserves are 10.41% and7.05%, respectively. The adsorbed gas reserves calculated by using the traditional method is lower, the matrix free gas reserves is higher and the total reserves is lower. In order to evaluate the gas in place of shale gas reservoirs rationally, it is necessary to adopt the multi-component adsorption model, and take into consideration the porosity of the adsorbed phase, as well as the free gas in fractures and the dissolved gas in kerogen.
引文
[1]梅海燕,何浪,张茂林,等.页岩油注气提高采收率现状及可行性分析[J].油气藏评价,2018,8(6):77-82.MEI Haiyan,HE Lang,ZHANG Maolin,et al.Status and feasibility analysis on improved shale-oil recovery by gas injection[J].Reservoir Evaluation and Development,2018,8(6):77-82.
[2]AMBROSE R J,HARTMAN R C,AKKUTLU I Y.Multi-component sorbed-phase consideration for shale gas in-place calculation[R].SPE 141416,2011.
[3]李艳丽.页岩气储量计算方法探讨[J].天然气地球科学,2009,20(3):466-470.LI Yanli.Calculation methods of shale gas reserves[J].Natural Gas Geoscience,2009,20(3):466-470.
[4]张金华,魏伟,钟太贤.国外页岩气资源储量评价方法分析[J].中外能源,2011,16(9):38-42.ZHANG Jinhua,WEI Wei,ZHONG Taixian.Evaluation methods analysis about resources and reserves of foreign shale gas[J].Sino-Global Energy,2011,16(9):38-42.
[5]李宏勋,张汶汶,王海军.基于中国特殊地质特性的页岩气储量评价方法研究[J].改革与战略,2013,29(11):43-45.LI Hongxun,ZHANG Wenwen,WANG Haijun.Evaluation methods analysis about resources and reserves of shale gas based on Chinese special geological characteristic[J].Reform&Strategy,2013,29(11):43-45.
[6]徐海霞,齐梅,赵书怀.页岩气容积法储量计算方法及实例应用[J].现代地质,2012,26(3):555-559.XU Haixia,QI Mei,ZHAO Shuhuai.Volumetric method of shale gas reserve calculation and a case application[J].Geoscience,2012,26(3):555-559.
[7]陈元千,李剑,齐亚东,等.页岩气藏地质资源量、可采资源量和井控可采储量的确定方法[J].新疆石油地质,2014,35(5):547-551.CHEN Yuanqian,LI Jian,QI Yadong,et al.Determination methods of geological resources,recoverable resources and well-controlled recoverable reserves in shale gas reservoir[J].Xinjiang Petroleum Geology,2014,35(5):547-551.
[8]曲占庆,林珊珊,张杰,等.多组分和吸附对页岩气储量计算的影响[J].特种油气藏,2012,19(3):114-116.QU Zhanqing,LIN Shanshan,ZHANG Jie,et al.Impacts of multi-component and adsorption on shale gas reserve estimation[J].Special Oil and Gas Reservoir,2012,19(3):114-116.
[9]姜瑞忠,乔欣,何吉祥,等.页岩气地质储量计算新方法[J].天然气地球科学,2016,27(4):699-705.JIANG Ruizhong,QIAO Xin,HE Jixiang,et al.A new method to calculate shale gas geological reserves[J].Natural Gas Geoscience,2016,27(4):699-705.
[10]杜华明,宁正福,苏朋辉.考虑多组分吸附的页岩气储量计算方法[J].地质科技情报,2017,36(2):141-145.DU Huaming,NING Zhengfu,SU Penghui.Calculation method of shale gas reserves by considering multi-component adsorption[J].Geological Science and Technology Information,2017,36(2):141-145.
[11]刘欢,李少明,李雪琴,等.物质平衡方法计算页岩储量[J].中国石油和化工,2014,21(11):52-53.LIU Huan,LI Shaoming,LI Xueqin,et al.The material balance method to calculate shale reserves[J].China Petroleum and Chemical Industry,2014,21(11):52-53.
[12]杨龙,梅海燕,张茂林,等.考虑干酪根中溶解气的页岩气藏储量计算方法[J].新疆石油地质,2016,37(5):602-605.YANG Long,MEI Haiyan,ZHANG Maolin,et al.Anew method to calculate shale gas reserves considering dissolved gas in kerogen[J].Xinjiang Petroleum Geo-logy,2016,37(5):602-605.
[13]王怀龙,张茂林,郭沙沙,等.新型裂缝性页岩气藏物质平衡方程[J].断块油气田,2015,22(2):202-205.WANG Huailong,ZHANG Maolin,GUO Shasha,et al.A new material balance equation for fractured shale gas reservoir[J].Fault-Block Oil&Gas Field,2015,22(2):202-205.
[14]AMBROSE R J,HARTMAN R C,DIAZ-CAMPOS M,et al.New pore-scale considerations for shale gas in place calculations[R].SPE 131772,2012.
[15]TIAB D,RESTREPO D P,LGBOKOYI A O.Fracture porosity of naturally fractured reservoirs[R].SPE104056,2006.
[16]AGUILERA R,LOPEZ B.Evaluation of quintuple porosity in shale petroleum reservoirs[R].SPE 165681,2013.
[17]WU P,AGUILERA R.Investigation of gas shales at nanoscale using scan electron microscopy,transmission electron microscopy and atomic force microscopy[R].SPE 159887,2012.
[18]MEHROTRA A K,SVRCEK W Y.Correlations for properties of bitumen saturated with CO2,CH4 and N2,and experiments with combustion gas mixtures[J].Journal of Canadian Petroleum Technology,1982,21(6):95-104.
[19]OROZCO D,AGUILERA R.A material balance equation for stress-sensitive shale gas reservoirs considering the contribution of free,adsorbed and dissolved gas[R].SPE 175964,2015.
[20]SWAMI V,SETTARI A,JAVADPOUR F.A numerical model for multi-mechanism flow in shale gas reservoirs with application to laboratory scale testing[R].SPE 164840,2013.
[21]SWAMI V,SETTARI A.A pore scale gas flow model for shale gas reservoir[R].SPE 155756,2012.
[2]AMBROSE R J,HARTMAN R C,AKKUTLU I Y.Multi-component sorbed-phase consideration for shale gas in-place calculation[R].SPE 141416,2011.
[3]李艳丽.页岩气储量计算方法探讨[J].天然气地球科学,2009,20(3):466-470.LI Yanli.Calculation methods of shale gas reserves[J].Natural Gas Geoscience,2009,20(3):466-470.
[4]张金华,魏伟,钟太贤.国外页岩气资源储量评价方法分析[J].中外能源,2011,16(9):38-42.ZHANG Jinhua,WEI Wei,ZHONG Taixian.Evaluation methods analysis about resources and reserves of foreign shale gas[J].Sino-Global Energy,2011,16(9):38-42.
[5]李宏勋,张汶汶,王海军.基于中国特殊地质特性的页岩气储量评价方法研究[J].改革与战略,2013,29(11):43-45.LI Hongxun,ZHANG Wenwen,WANG Haijun.Evaluation methods analysis about resources and reserves of shale gas based on Chinese special geological characteristic[J].Reform&Strategy,2013,29(11):43-45.
[6]徐海霞,齐梅,赵书怀.页岩气容积法储量计算方法及实例应用[J].现代地质,2012,26(3):555-559.XU Haixia,QI Mei,ZHAO Shuhuai.Volumetric method of shale gas reserve calculation and a case application[J].Geoscience,2012,26(3):555-559.
[7]陈元千,李剑,齐亚东,等.页岩气藏地质资源量、可采资源量和井控可采储量的确定方法[J].新疆石油地质,2014,35(5):547-551.CHEN Yuanqian,LI Jian,QI Yadong,et al.Determination methods of geological resources,recoverable resources and well-controlled recoverable reserves in shale gas reservoir[J].Xinjiang Petroleum Geology,2014,35(5):547-551.
[8]曲占庆,林珊珊,张杰,等.多组分和吸附对页岩气储量计算的影响[J].特种油气藏,2012,19(3):114-116.QU Zhanqing,LIN Shanshan,ZHANG Jie,et al.Impacts of multi-component and adsorption on shale gas reserve estimation[J].Special Oil and Gas Reservoir,2012,19(3):114-116.
[9]姜瑞忠,乔欣,何吉祥,等.页岩气地质储量计算新方法[J].天然气地球科学,2016,27(4):699-705.JIANG Ruizhong,QIAO Xin,HE Jixiang,et al.A new method to calculate shale gas geological reserves[J].Natural Gas Geoscience,2016,27(4):699-705.
[10]杜华明,宁正福,苏朋辉.考虑多组分吸附的页岩气储量计算方法[J].地质科技情报,2017,36(2):141-145.DU Huaming,NING Zhengfu,SU Penghui.Calculation method of shale gas reserves by considering multi-component adsorption[J].Geological Science and Technology Information,2017,36(2):141-145.
[11]刘欢,李少明,李雪琴,等.物质平衡方法计算页岩储量[J].中国石油和化工,2014,21(11):52-53.LIU Huan,LI Shaoming,LI Xueqin,et al.The material balance method to calculate shale reserves[J].China Petroleum and Chemical Industry,2014,21(11):52-53.
[12]杨龙,梅海燕,张茂林,等.考虑干酪根中溶解气的页岩气藏储量计算方法[J].新疆石油地质,2016,37(5):602-605.YANG Long,MEI Haiyan,ZHANG Maolin,et al.Anew method to calculate shale gas reserves considering dissolved gas in kerogen[J].Xinjiang Petroleum Geo-logy,2016,37(5):602-605.
[13]王怀龙,张茂林,郭沙沙,等.新型裂缝性页岩气藏物质平衡方程[J].断块油气田,2015,22(2):202-205.WANG Huailong,ZHANG Maolin,GUO Shasha,et al.A new material balance equation for fractured shale gas reservoir[J].Fault-Block Oil&Gas Field,2015,22(2):202-205.
[14]AMBROSE R J,HARTMAN R C,DIAZ-CAMPOS M,et al.New pore-scale considerations for shale gas in place calculations[R].SPE 131772,2012.
[15]TIAB D,RESTREPO D P,LGBOKOYI A O.Fracture porosity of naturally fractured reservoirs[R].SPE104056,2006.
[16]AGUILERA R,LOPEZ B.Evaluation of quintuple porosity in shale petroleum reservoirs[R].SPE 165681,2013.
[17]WU P,AGUILERA R.Investigation of gas shales at nanoscale using scan electron microscopy,transmission electron microscopy and atomic force microscopy[R].SPE 159887,2012.
[18]MEHROTRA A K,SVRCEK W Y.Correlations for properties of bitumen saturated with CO2,CH4 and N2,and experiments with combustion gas mixtures[J].Journal of Canadian Petroleum Technology,1982,21(6):95-104.
[19]OROZCO D,AGUILERA R.A material balance equation for stress-sensitive shale gas reservoirs considering the contribution of free,adsorbed and dissolved gas[R].SPE 175964,2015.
[20]SWAMI V,SETTARI A,JAVADPOUR F.A numerical model for multi-mechanism flow in shale gas reservoirs with application to laboratory scale testing[R].SPE 164840,2013.
[21]SWAMI V,SETTARI A.A pore scale gas flow model for shale gas reservoir[R].SPE 155756,2012.