TITLE:
Enhancing the Productivity of Niger Delta Shale Formation through Matrix Stimulation: An Experimental Study
AUTHORS:
Anthony Kerunwa, Ndubuisi U. Okereke, Ifeanyi Tasiewojiewhor
KEYWORDS:
Acidizing, Recovery, Hydraulic Fracturing, Permeability
JOURNAL NAME:
Open Journal of Yangtze Oil and Gas,
Vol.5 No.3,
June
9,
2020
ABSTRACT: Shales have very low permeabilities often within the range of nanodarcies and as such production from shales have been complex and challenging because of poor conductive network. In this work, experiments were conducted to ascertain the effect of matrix acidizing on oil recovery of shale formation in the Niger Delta. Four core samples, S1, S2, S3 and S4 gotten from the Niger Delta shale formation were used. Experiments carried out focused on gas flooding using nitrogen gas at pressures of 1300 psia, 1800 psia and 2300 psia before acid treatment and acidizing with HCL as the choiced acid at different concentrations. XRD was used to analyze the mineral content of the core samples and the analyzed result shows that the predominant mineral constituents of the shale samples are calcite (47%) and dolomite (11%), which are HCl acid soluble constituents. At the end of the experiment, study revealed increase in oil production indicating enhanced productivity as a result of acid treatment and appropriate injection pressure of 800 psia. The result also revealed that the penetration rate in the range of 247.66 min/in to 139.95 min/in before acid treatment decreased to the range 21.67 min/in to 6.61 min/in after acid treatment.