This paper presents a case history of successful acid stimulation treatments on acid sensitive crude producers in the Gulf of Mexico at Main Pass 313 producers in the Gulf of Mexico at Main Pass 313 field. It shows how catastrophic emulsion and facility upset problems encountered during the flowback of the first well in a multi-well stimulation program were resolved and used as the basis for optimizing treatment design on the remaining wells. Overall, it demonstrates how taking a preventative posture through a total system approach to the stimulation process was the key to solving the acid treatment process was the key to solving the acid treatment flowback problems experienced.
Matrix acidizing is commonly practiced in the Gulf of Mexico to optimize near wellbore flow efficiency by removing skin. The focus of this paper deals with acid system flowback problems experienced following the Main Pass 313 Well K stimulation and subsequent changes made to resolve those problems.
The Well K stimulation was the first in a planned 12 well stimulation package. Pre-stimulation evaluations along with stimulation design and techniques used were those found to be successful on previous Main Pass well stimulations. Following the Well K Pass well stimulations. Following the Well K treatment, a catastrophic emulsion and facility upset was experienced. Attempts to chemically treat the emulsion problems at surface during the acid flowback were unsuccessful. After several days spent attempting to resolve the facility upset following the Well K treatment and subsequent shut-in, the Well K production was diverted to a holding barge until its production was diverted to a holding barge until its cleanup was completed. The subject emulsified crude then had to be barged in and disposed of at great expense to the operator. Well performance did increase as a result of the treatment. However, due to the additional expenses incurred during post-stimulation well flowback, strong consideration was post-stimulation well flowback, strong consideration was given to cancellation of any further stimulations previously planned for the platform. previously planned for the platform. A concentrated effort was initiated to closely examine and resolve the facility upset problems observed in the field. A total system approach examining all controllable factors of the stimulation process affecting the facility upsets on the platform was conducted. This "total system" approach encompassed evaluation of the following:
Acid/crude compatibility testing(prestimulation)
Commingled fluids analysis (pre-stimulation)