Abstract
This paper presents experiences gained from several Chemical sand consolidation treatments performed in one of the field in West Africa. Success rate was 60% and there were learnings from failures. Case studies for several wells are provided to highlight the key aspect and learnings which are essential to improve the chances of any sand consolidation treatment.
Chemical Sand consolidation (SCON) treatment provides in situ sand influx control by treating the incompetent formation around the wellbore itself. The treatment consists of injecting the immediate near wellbore area of the reservoir with a fluid containing an adhesive or epoxy resins, which increases the strength of the formation without significant loss of permeability. The ideal sand consolidation system provides the highest possible resistance to sand production at the lowest impairment. However, there are many factors which generally not thought of could lead to potential job failure. Several SCON treatments have been done in the field. Of the total number of jobs conducted over time, there were some failures reported as well therefore a detailed after action review was conducted which highlighted some important factors responsible for failure. The factors responsible for the failure of these wells were found non-associated with each other. Key areas like candidate selection, well preparation prior to SCON treatment, design and modeling, SCON chemical validation and testing, job execution, well start-up post treatment were looked into details to summarize the findings. For successful SCON treatment, well preparation is very important. Well preparation conveyance method is typically coil tubing unit, bullheading or workover. Especially well preparation via either means requires extra considerations therefore some important learning will also be discussed apart from SCON treatment aspect.
The findings and learnings from these jobs were incorporated into future campaigns to maximize the success. Sand consolidation proved to be a successful means to add production gains in a low cost environment.
