Hydrocarbon production from unconsolidated sand reservoirs requires sand control usually consisting of the installation of a screen combined with gravelpacking. Several existing criteria such as Tiffin, Saucier and Coberly can be used for optimal selection of the sand control design. Sand and fines production in oil and gas wells are one of the main challenges and can result in failures of production systems. Especially in unconsolidated sand reservoirs, proper sand control practices are required to prevent reservoir sand production. At Staatsolie sizing of sand control design is based on the Saucier method incorporating the results of reservoir sand particle size distribution of side wall core samples.
A Staatsolie-Suriname in-depth research of sand control practices in shallow, low-pressure, heavy-oil unconsolidated sand reservoirs completed with progressive cavity pumps will be presented. The conventional sand control method applied is the installation of formation sand sized wire wrapped screens and gravelpack completion on uniform and non-uniform distributed reservoir sands. Stand alone screen completions have revealed its application in uniform distributed reservoir sands. Sand production and control on depleted and complex reservoirs based on the conventional method has become a major challenge. In Suriname, in three onshore fields approximately 1,500 wells are completed and are in production. With improved sand control practices, failures have been reduced to less than 5 wells per year.
The study has demonstrated the challenges and benefits of sand control in these complex unconsolidated Tertiary reservoirs. This has resulted into increased production and economic benefits. Results of lab tests and field cases will be presented and recommendations will be given on the best approach for sand control practices and the most cost effective sand control solutions in unconsolidated shallow sand reservoirs.