This paper presents a cost analysis / comparative study of the return on investment realized from the downhole chemical treatment of the Coora CO365 well. The technologies available to permanently outfit older wells that are completed with sub-surface safety valves (SSSVs), with the ability to benefit from direct down-hole chemical remediation, are also detailed.
Producing from a field that was first developed in 1936 and located in southern Trinidad, Coora CO365 experienced paraffin deposition in the near-wellbore and along the well's production string early in its productive life. The operator followed long-term strategic workover plans, but paraffin deposition still continued. Further investigation highlighted that the implementation of an optimal chemical injection program would be critical to realize maximum financial benefit from production of this maturing reservoir.
The operator has been able to replace high-cost workovers with low-cost chemical treatment, significantly improving the economics and prolonging the productive life of this well. Through comparison with older wells (in this block), completed without direct downhole means of chemical remediation, this case will show that simple modifications, though incurring upfront capital cost, can result in long-term revenue generation and early payback, if combined with an appropriate chemical remediation package. The analysis will dispel the common misconception that the cost incurred in refitting older wells with downhole injection capabilities overshadows their revenue generation prospects.
In many cases, the natural decline of a field can be exacerbated by flow-assurance issues in wells and equipment. This paper highlights the potential to sustain production in brownfields that have been plagued with these issues via the use of downhole chemical injection.