Shaped Memory Polymer: An Innovative Approach to Sand Control Open Hole Completion in Thin, Multilayered, Depleted Low Permeability Gas Reservoirs

This paper details a field application of Shaped Memory Polymer (SMP) material for sand management delivering an innovative approach for sand control completions. The use of the technology has enabled profitable exploitation of residual reserves in a mature gas field offshore Adriatic Sea. The paper reviews details of the field deployment, with both economic and well performance results described. The offshore field was discovered in 1971 and 102 wells have been drilled to date. The trap is a very gentle, slightly asymmetrical anticline made by Pleistocene sandy turbidites, sedimented on the underlying carbonate substrate. Methane gas bearing layers have been sealed by several argillaceous intercalations that worked also as the source rocks of this multilayer reservoir. The sandy layers in this Pleistocene sequence, have thickness ranging from few centimeters up to some meters, and porosity from 22 up to 33%. Isolation of multiple gas-water contacts and fines production have been two crucial issues while producing the field. Since 2000, all seven platforms in this field have required workovers by means of performing sidetracks. Due to the reservoir characteristics, the well interventions have been completed with multi-layer, stacked cased-hole sand control completions. Despite a continuous improvement of procedures and technique, the traditional sand control methods have been efficient but were no longer profitable, due to challenging market conditions. An open-hole completion using SMP combined with zonal isolation and selective production has proved to be an effective alternative to cased-hole sand control. This novel completion approach resulted in a significant reduction in both cost and rig time. It is estimated that nearly two weeks of rig time was saved and an overall workover cost reduction of approximately 35%, with further efficiencies to be realized on upcoming deployments. To date, the completion has proved to be an effective sand control method, with no produced solids, no plugging effect, and gas production that has met expectations.