Optimization of Matrix Acidizing With Fluids Diversion in Real-Time Using Distributed Temperature Sensing and Coiled Tubing

摘要

Carbonate formations in southern Mexico are commonly stimulated using matrix acidizing treatments to increase well productivity by removing near-wellbore (NWB) damage. Such damage can be attributed to accumulation of paraffin and asphaltene deposits during the productive life of the well and, in other scenarios, to fluid invasion while performing workover activities. A high perforation length across the reservoir to increase production from this highly natural-fractured carbonate has been the completion option for several years. The use of diverters is a common practice in the Bellota-Jujo field when multiple intervals are open. However, the effectiveness of the diversion had not been evaluated in real-time. A distributed temperature sensing (DTS) option was deployed to measure temperature profiles along coiled tubing (CT) equipped with an internal fiber-optic cable and a modular bottomhole assembly (BHA) consisting of pressure, temperature, and depth correlation sensors. This option was selected to monitor the treatment and help make real-time decisions. This real-time fiber-optic (RTFO) integrated system used during the stimulation allowed identification of zones with higher and lower admission. Based on this information, decisions were made during the pumping schedule, modifying volumes and rates of diverting agents and stimulation fluids being pumped through the annular space between production tubing and CT, also pumping through CT using a fluidic oscillating tool optimizing the diversion process during different stages of the intervention. This system enabled the operator to correlate depth and continuously monitor the temperature changes across the producing zone of the well. The findings and results of the stimulation treatment with this technique used in the well, Bricol 2DL, are presented in addition to the thermal analysis of the DTS profiles. The use of the RTFO integrated system during a matrix stimulation treatment in a carbonate formation with high permeability contributed to successfully evaluating the effectiveness of the fluids and mechanical diversion resulting in a well productivity increase of 60%, thus keeping the well in production since the treatment was performed.