Polymeric Solutions to High Gas Influx in an Oil Producing Well: A Field Experience

Abstract

Abstract Petroleum production engineering aims to maximize oil and gas production in a cost-effective manner. Wells in one reservoir can be considered oil, condensate and gas wells, depending on the producing gas-to-oil ratio. As the wells produce, this designation can change, for example as oil is produced and gas or water reaches the perforated interval and becomes dominant in the production stream. This type of change is often undesirable and requires intervention to restore preferred productivity. This paper describes a gas-shutoff intervention operation in an oil-producing well. The well was initially completed in September 1974, but recently the two upper sets of perforation began to produce excessive gas. The operator wanted to cease producing from those perforations and instead produce only the lower (oil-producing) perforations. After considering various gas-shutoff options, the operator chose to use a permanent polymeric gel for the operation. The gel is formulated with low-molecular-weight polymers, which penetrate into the matrix pore spaces for a complete shutoff squeeze treatment. This paper will describe laboratory testing, field experiences, challenges and operational procedures to create a number of conclusions about lessons learned and best practices for polymeric gels in gas shutoff operations.