Evaluation of Matrix Acidizing Program to Increase Production Profile of X-25 Wells, Y Field

Abstract

In line with the increasing time, oil and gas wells will decrease their production, and the production decrease will faster with the presence of production problems associated with the performance of its reservoir as well, such as damage to formation. The occurrence of formation damage resulted in lower permeability than the initial permeability value. S-25 Well of Y Field, which is located in West Papua is a well formation damage, has recorded the gross production decreased to1491.2 BFPD with net production of 11.9 BOPD. from 2 reservoir targets, Limestone of the Kais and Faumi or Pre-Kais Formation. Therefore, the matrix acidizing stimulation program needs to be done to improve the production profile of the S-25 well particularly in Kais limestone reservoir.

To execute the matrix acidizing program requires several steps began from calculation, analysis and evaluation of its success rate. The matrix acidizing requires injection volume of 3663,126 liters with an injection fluid composition comprising of 312,5 GPT (HCI 10%) of 1,144,726 liters and fresh water 6875 GPT (90%) of 2518.398 liters. Displacing fluid material was using fresh water with a volume of 426.187 liters. The injection pressure required to inject the acid solution is 3.32 BPM with maximum pressure on the surface of 183.22 psi.

The evaluation results show that the gross production before matrix acidizing is 1491.2 BFPD with net 11.9 BOPD, and has increased to 2214.8 BFPD with net 15.5 BOPD after the matrix acidizing program run. Then the Productivity index (PI) of before and after matrix acidizing is 36.9 BFPD/psi and 49.4 BFPD/psi. Based on the Inflow Performance Relationship (IPR) curve, the Qt max value before and after matrix acidizing also increased from 2550 BFPD to 3895 BFPD. The success rate percentage of the matrix acidizing program on the S-25 Well is 48,52%.