Hot water flooding is an effective way to develop heavy oil reservoirs.However,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the reservoir.The pore s...Hot water flooding is an effective way to develop heavy oil reservoirs.However,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the reservoir.The pore structure heterogeneity is an important factor in forming these channels.This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are conducted.During the experiments,computer tomography(CT)scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels.The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity.The zone where oil saturation reduction exceeds 20%is defined as a channeling channel.The scanning area is divided into 180 equally sized zones based on the CT scanning images,and threedimensional(3D)distributions of the channeling channels are developed.Four micro remaining oil distribution patterns are proposed,and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed.The results show that hot water flooding is more balanced in the weakly heterogeneous model,and the oil saturation decreases by more than 20%in most zones without narrow channeling channels forming.In the strongly heterogeneous model,hot water flooding is unbalanced,and three narrow channeling channels of different lengths form.In the weakly heterogeneous model,the oil saturation reduction is greater in zones with larger pores.The distribution range of the average pore size is larger in the strongly heterogeneous model.The network remaining oil inside the channeling channels is less than outside the channeling channels,and the hot water converts the network remaining oil into cluster,film,and droplet remaining oil.展开更多
With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric...With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric heating leads to considerable electrical consumption, low injection water temperature decreases reservoir temperature and increased crude oil viscosity. The prolonged temperature difference break up reservoir pore throat cement and framework minerals. To improve high-capacity channel communication, we proposed geothermal oil recovery. Broad-sense abundant geothermal resources and existing injection water technique equipment are used, deep-seated high temperature liquid (oil-gas-water mixture) draws geothermal warming flowing layer to transit heat upward, decreases viscidity and increases fluidity. Reservoir temperature different offer geothermal fountain. Practicability process is analyzed. statistics and reservoir temperature variation analysis of Gudong Oilfield, Shengli Oilfield Company, SINOPEC, we have designed flow-chart concept for geothermal oil recovery, suggested drilling multi-branch well in heavy oil reservoir as injection-well, at the same position of geothermal fountain well, using free-pressure pump to inject hot liquid directly to aimed oil layer, made oil recovery in surrounding wells. It is proposed that geothermal oil recovery forerunner test should be first conducted in favorable blocks.展开更多
基金supported by the National Key Research and Development Program of China (Grant No.2018YFA0702400)the National Natural Science Foundation of China (Grant No.52174050)+1 种基金the Natural Science Foundation of Shandong Province (Grant No.ZR2020ME088)the National Natural Science Foundation of Qingdao (Grant No.23-2-1-227-zyyd-jch)。
文摘Hot water flooding is an effective way to develop heavy oil reservoirs.However,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the reservoir.The pore structure heterogeneity is an important factor in forming these channels.This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are conducted.During the experiments,computer tomography(CT)scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels.The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity.The zone where oil saturation reduction exceeds 20%is defined as a channeling channel.The scanning area is divided into 180 equally sized zones based on the CT scanning images,and threedimensional(3D)distributions of the channeling channels are developed.Four micro remaining oil distribution patterns are proposed,and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed.The results show that hot water flooding is more balanced in the weakly heterogeneous model,and the oil saturation decreases by more than 20%in most zones without narrow channeling channels forming.In the strongly heterogeneous model,hot water flooding is unbalanced,and three narrow channeling channels of different lengths form.In the weakly heterogeneous model,the oil saturation reduction is greater in zones with larger pores.The distribution range of the average pore size is larger in the strongly heterogeneous model.The network remaining oil inside the channeling channels is less than outside the channeling channels,and the hot water converts the network remaining oil into cluster,film,and droplet remaining oil.
文摘With the rapid development of Chinese petroleum industry, Oil production way of burning crude oil to produce steam need change. Heavy oil reservoir with thin layer or edgewater is unsuitable thermal recovery, electric heating leads to considerable electrical consumption, low injection water temperature decreases reservoir temperature and increased crude oil viscosity. The prolonged temperature difference break up reservoir pore throat cement and framework minerals. To improve high-capacity channel communication, we proposed geothermal oil recovery. Broad-sense abundant geothermal resources and existing injection water technique equipment are used, deep-seated high temperature liquid (oil-gas-water mixture) draws geothermal warming flowing layer to transit heat upward, decreases viscidity and increases fluidity. Reservoir temperature different offer geothermal fountain. Practicability process is analyzed. statistics and reservoir temperature variation analysis of Gudong Oilfield, Shengli Oilfield Company, SINOPEC, we have designed flow-chart concept for geothermal oil recovery, suggested drilling multi-branch well in heavy oil reservoir as injection-well, at the same position of geothermal fountain well, using free-pressure pump to inject hot liquid directly to aimed oil layer, made oil recovery in surrounding wells. It is proposed that geothermal oil recovery forerunner test should be first conducted in favorable blocks.