Authors :
Imad Biboye Eseimokumoh; Omuso-Wilson Ereyananyo; Oguta Eniye
Volume/Issue :
Volume 6 - 2021, Issue 7 - July
Google Scholar :
http://bitly.ws/9nMw
Scribd :
https://bit.ly/3x9b9lO
Abstract :
Reservoir formation damage is the impairment
of the reservoir rock permeability which causes reduction
in the productivity of a well. The quantification of
wellbore formation damage using pressure transient
analysis (PTA) is vital in the oil and gas industry as it
helps to interpret key physical reservoir parameters to
improve wellbore and reservoir management strategies
for production optimization. In this paper, a single rate
build-up test data generated from a vertical producing oil
WELL X was analysed. Pressure transient was due to the
pressure decline in the high permeability Niger Delta
sandstone formation. Reduction in productivity index
may have been caused by wellbore or formation damage
as a result of pseudoskin due to completion (mechanical
skin) or perforation, fines migration, inorganic scale
deposition, or organic solids deposition in the near
wellbore region. In order to resolve this problem and
optimize production from this well, generated build-up
pressure time data at a constant production rate was
analysed to determine reservoir and wellbore parameters.
The damage in the near wellbore zone is simulated using a
numerical well test simulator (KAPPA-saphir); and the
same build-up test data was analysed using the
conventional method alongside with Microsoft Excel
Sheet to estimate the reservoir and wellbore parameters
like skin, average reservoir permeability, wellbore storage
effect, and average reservoir pressure. The results
obtained from the numerical well test simulator, and
analytical solutions using Microsoft Excel Sheet were
compared to ascertain the effectiveness of the numerical
simulator in conducting pressure transient analysis on the
measured data. Both analysis on the generated build-up
test data showed close results for skin and permeability
value, hence, the very high skin and permeability value
obtained after analysis indicate damage due to mechanical
or wellbore skin. This reveals that the vertical oil
producing well of this field is a candidate well for
workover operations
Keywords :
Reservoir Formation Damage, Wellbore, Production, Skin, Permeability, Numerical Simulator, BuildUp Test, Pressure Transient Analysis, Workover Operation
Reservoir formation damage is the impairment
of the reservoir rock permeability which causes reduction
in the productivity of a well. The quantification of
wellbore formation damage using pressure transient
analysis (PTA) is vital in the oil and gas industry as it
helps to interpret key physical reservoir parameters to
improve wellbore and reservoir management strategies
for production optimization. In this paper, a single rate
build-up test data generated from a vertical producing oil
WELL X was analysed. Pressure transient was due to the
pressure decline in the high permeability Niger Delta
sandstone formation. Reduction in productivity index
may have been caused by wellbore or formation damage
as a result of pseudoskin due to completion (mechanical
skin) or perforation, fines migration, inorganic scale
deposition, or organic solids deposition in the near
wellbore region. In order to resolve this problem and
optimize production from this well, generated build-up
pressure time data at a constant production rate was
analysed to determine reservoir and wellbore parameters.
The damage in the near wellbore zone is simulated using a
numerical well test simulator (KAPPA-saphir); and the
same build-up test data was analysed using the
conventional method alongside with Microsoft Excel
Sheet to estimate the reservoir and wellbore parameters
like skin, average reservoir permeability, wellbore storage
effect, and average reservoir pressure. The results
obtained from the numerical well test simulator, and
analytical solutions using Microsoft Excel Sheet were
compared to ascertain the effectiveness of the numerical
simulator in conducting pressure transient analysis on the
measured data. Both analysis on the generated build-up
test data showed close results for skin and permeability
value, hence, the very high skin and permeability value
obtained after analysis indicate damage due to mechanical
or wellbore skin. This reveals that the vertical oil
producing well of this field is a candidate well for
workover operations
Keywords :
Reservoir Formation Damage, Wellbore, Production, Skin, Permeability, Numerical Simulator, BuildUp Test, Pressure Transient Analysis, Workover Operation
