新疆石油地质

新疆石油地质 ›› 2021, Vol. 42 ›› Issue (zk(English)): 109-115.

• • 上一篇    下一篇

Division and Application of Gas/Water Occurrence Models in High⁃Rank Coal Reservoirs

LIU Zhong1,2, WANG Ning1,2, ZHANG Yongping1,2, LU Xiuqin1,2, LI Zheng3, GAO Yan2   

  1. 1. CBM Exploration, Development Pilot Test Base, CNPC, Renqiu, Hebei 062552, China;
    2. Research Institute of Exploration, Development, Huabei Oilfield Company, PetroChina, Renqiu, Hebei 062552, China;
    3. School of Petroleum Engineering, China University of Petroleum, Qingdao, Shandong 266580, China
  • 出版日期:2022-01-01 发布日期:2023-07-28

Division and Application of Gas/Water Occurrence Models in High⁃Rank Coal Reservoirs

LIU Zhong1,2, WANG Ning1,2, ZHANG Yongping1,2, LU Xiuqin1,2, LI Zheng3, GAO Yan2   

  1. 1. CBM Exploration, Development Pilot Test Base, CNPC, Renqiu, Hebei 062552, China;
    2. Research Institute of Exploration, Development, Huabei Oilfield Company, PetroChina, Renqiu, Hebei 062552, China;
    3. School of Petroleum Engineering, China University of Petroleum, Qingdao, Shandong 266580, China
  • Online:2022-01-01 Published:2023-07-28
  • About author:LIU Zhong, E-mail: mcq_liuz@petrochina.com.cn

PDF

16

摘要： By analyzing the factors controlling hydrocarbon accumulation in Zhengzhuang block and Mabidong block in the southern Qinshui basin, and using molecular simulation technology, the microscopic laws of gas/water occurrence in the coal reservoirs were studied, then the occurrence models of methane in microscopic pores were demonstrated, and finally dynamic balance occurrence models considering the dynamic boundary effect of low-permeability fractures were established based on evaluation well data (i.e. measured gas content, fracturing stimulation and production data), microfracture models and boundary layer effects. The results show that anhydrous methane mainly adsorbs to the pores with a diameter of 2 nm, and as the gas saturation increases, the competition among water molecules weakens. The balance relationship among viscous force, gas/water phase pressure and capillary force is defined. The gas/water pressure balance models are divided into escaping and occluding models. After analyzing the influences of 4 types of gas/water occurrence models on later production, it is believed that the gas output of Type III and Type IV models is relatively higher.

关键词: Qinshui basin, coal reservoir, gas/water occurrence model, molecular simulation, dynamic boundary balance, critical desorption pressure

Abstract: By analyzing the factors controlling hydrocarbon accumulation in Zhengzhuang block and Mabidong block in the southern Qinshui basin, and using molecular simulation technology, the microscopic laws of gas/water occurrence in the coal reservoirs were studied, then the occurrence models of methane in microscopic pores were demonstrated, and finally dynamic balance occurrence models considering the dynamic boundary effect of low-permeability fractures were established based on evaluation well data (i.e. measured gas content, fracturing stimulation and production data), microfracture models and boundary layer effects. The results show that anhydrous methane mainly adsorbs to the pores with a diameter of 2 nm, and as the gas saturation increases, the competition among water molecules weakens. The balance relationship among viscous force, gas/water phase pressure and capillary force is defined. The gas/water pressure balance models are divided into escaping and occluding models. After analyzing the influences of 4 types of gas/water occurrence models on later production, it is believed that the gas output of Type III and Type IV models is relatively higher.

Key words: Qinshui basin, coal reservoir, gas/water occurrence model, molecular simulation, dynamic boundary balance, critical desorption pressure