Conceptual Flow Assurance Design of an Expanding Carbon Capture and Storage Transport Network

Abstract Designing a single-source-sink CO2 transport network is straightforward, but complexities arise when multiple emitters connect to a shared network, as in industrial CCS clusters. Typically, networks are designed based on a fixed time-invariant infrastructure. Designers face choices about pre-investing in large pipelines or building for average demand with the risk of future capacity issues or when and where additional boosting is required. In this paper we present a phased CCS network design that adapts over time, using "system constraints maps" to visualize component interactions and identify needed modifications for efficient, scalable expansion. Our methodology is based on the development of constraints maps that help visualize various design and operational limits. This enables designers to propose a strategy (pipeline upgrades, pressure boosting, etc.) to ensure that the infrastructure is fit-for-purpose. Rigorous steady-state flow assurance simulations are carried out to develop the maps. We have used an integrated full-chain model from the inlet of the pipeline to the sandface (but not the reservoir itself). Maps are constructed based on various criteria, for example, finding parameters that will avoid two-phase flow in the pipelines or will allow start operation with an existing infrastructure. Our case study considers various emitters sending CO2 to an onshore/offshore transport system for injection to three highly depleted gas reservoirs. The analysis has identified several trade-offs, and an operating strategy has been developed to satisfy and accommodate several design constraints. We have considered reusing existing facilities and that upgrades will be required over time. We showed that the existing facilities, with minor modifications, are adequate for transportation and injection of a flowrate of 1.5 MtCO2/year until a bottom hole pressure of 30 bar is reached. We map modifications and upgrades that will expand the system capacity to more than 5 MtCO2/year. The configuration shown in this work provides the most cost-effective and low risk system. This option offers the most flexible road map for rapid deployment if infrastructure is already in place. Planning and designing CCS transport networks requires deep understanding of interactions of the elements of the system. We show how a full-chain holistic approach provides a bigger picture and its benefits at early stages of engineering design. System envelopes help to identify bottlenecks and propose modifications to the system to enable continuous flow. These maps can be developed for any CCS transport system regardless of the configuration or if it is newly built or existing.