Effect of depletion rate on wellbore stability due to production of oil from hydrocarbon-bearing reser-voirs is important and can result in a reduction of the reservoir pore pressure.A reduction in the reservoir press...Effect of depletion rate on wellbore stability due to production of oil from hydrocarbon-bearing reser-voirs is important and can result in a reduction of the reservoir pore pressure.A reduction in the reservoir pressure,in tum,results in a change in the stresses acting within the reservoir.If these changes are not well analyzed and applied in future calculations,we may be unsuccessful in some cases such as drilling infill wells or extended wells,forecast of sand production and optimum flow rate,preventing of casing collapse,etc.Therefore,knowing the stresses around the well at every stage of production is fundamental to the next calculations.In this paper,we recognized these changes in near-wellbore stresses using data from logging(image log,dipole sonic,full set log,mud log),production data,infor-mation from kick,blow out,loss etc.and determined it using Techlog software and theoretical calcu-lations.Three wells of two huge oilfields of sw Iran were investigated after depletion or production for long years.In each well,state of stresses were calculated in cases of safe drilling mud weight using log data and theoretical equations.At the end effect of depletion rate on wellbore stability was investigated in these three wells.展开更多
With the enormous increase in the demand for crude oil,and decrease in the resources of conventional oil reservoirs,there is a great need to understand heavy or foamy oil-gas drive mechanism to maximize the oil and ga...With the enormous increase in the demand for crude oil,and decrease in the resources of conventional oil reservoirs,there is a great need to understand heavy or foamy oil-gas drive mechanism to maximize the oil and gas production.To analyze the real movement of non-viscous heavy oil flow,the characteristic features of the oil-gas mixture has to be estimated to forecast the future potential supply from a heavy oil reservoir.An important question in heavy oil flow under solution gas drive is whether the behaviour of depletion tests can be simulated to model the heavy oil flow behaviour.The main objective of this research is to develop a reliable numerical model for modelling heavy oil flow calibrated with controlled solution gas drive experiments,and that makes a novelty in this manuscript.In this paper,CMG-STARS model which is capable of simulating solution gas drive tests that matched the research experiments.This heavy oil recovery model can determine the relative permeability curves for oil and gas in the dualphase system using Corey’s relations.At a depletion rate of 0.0418 psi/min,the maximum cumulative oil and gas production was observed to be 13,000 cm^(3)and 8500 cm^(3),respectively.The results from the bottom hole pressure and the block pressure simulation runs indicate that the fluid properties such as surface tension plays a significant role in the gas bubble formation.These results are promising,and helps to understand the complex behaviour of heavy oil reservoirs and thus can improve heavy oil recovery.展开更多
文摘Effect of depletion rate on wellbore stability due to production of oil from hydrocarbon-bearing reser-voirs is important and can result in a reduction of the reservoir pore pressure.A reduction in the reservoir pressure,in tum,results in a change in the stresses acting within the reservoir.If these changes are not well analyzed and applied in future calculations,we may be unsuccessful in some cases such as drilling infill wells or extended wells,forecast of sand production and optimum flow rate,preventing of casing collapse,etc.Therefore,knowing the stresses around the well at every stage of production is fundamental to the next calculations.In this paper,we recognized these changes in near-wellbore stresses using data from logging(image log,dipole sonic,full set log,mud log),production data,infor-mation from kick,blow out,loss etc.and determined it using Techlog software and theoretical calcu-lations.Three wells of two huge oilfields of sw Iran were investigated after depletion or production for long years.In each well,state of stresses were calculated in cases of safe drilling mud weight using log data and theoretical equations.At the end effect of depletion rate on wellbore stability was investigated in these three wells.
文摘With the enormous increase in the demand for crude oil,and decrease in the resources of conventional oil reservoirs,there is a great need to understand heavy or foamy oil-gas drive mechanism to maximize the oil and gas production.To analyze the real movement of non-viscous heavy oil flow,the characteristic features of the oil-gas mixture has to be estimated to forecast the future potential supply from a heavy oil reservoir.An important question in heavy oil flow under solution gas drive is whether the behaviour of depletion tests can be simulated to model the heavy oil flow behaviour.The main objective of this research is to develop a reliable numerical model for modelling heavy oil flow calibrated with controlled solution gas drive experiments,and that makes a novelty in this manuscript.In this paper,CMG-STARS model which is capable of simulating solution gas drive tests that matched the research experiments.This heavy oil recovery model can determine the relative permeability curves for oil and gas in the dualphase system using Corey’s relations.At a depletion rate of 0.0418 psi/min,the maximum cumulative oil and gas production was observed to be 13,000 cm^(3)and 8500 cm^(3),respectively.The results from the bottom hole pressure and the block pressure simulation runs indicate that the fluid properties such as surface tension plays a significant role in the gas bubble formation.These results are promising,and helps to understand the complex behaviour of heavy oil reservoirs and thus can improve heavy oil recovery.
