Technical and Environmental Evaluation of a Hydrate Cold Flow Technique to Produce an Oil Reservoir Using a Long Tie-Back and Comparison Against Traditional Development Concepts

Abstract

In Norway, the majority of offshore oil and gas fields will be developed through tie-back solutions. Here, the produced reservoir streams are transported over long distances on irregular terrain and cold ambient temperatures to processing facilities. This might result in the formation of hydrate particles that can lead to increased pressure drop and gradual or sudden plugging of the pipe. Measures to address them tend to be expensive or have a high environmental footprint. An alternative measure less costly and more environmentally friendly is the cold flow technology. Here, hydrates are formed under controlled conditions, resulting in a stable particle slurry that does not agglomerate and plugs the pipeline downstream. This study presents a technical and environmental evaluation of cold flow as a flow assurance technique to produce an oil reservoir using a long tie-back. The case study is a synthetic field located on the Norwegian Continental Shelf. Results show that cold flow can successfully be used to produce the reservoir with lower emissions. The advantages and limitations of the concept were identified and discussed, and a comparison is made against alternatives, considering energy consumption, emissions during operation, and carbon footprint.