OLGA Robust, Enhanced and Accurate CO₂ Handling (OLGA CO₂ REACH)

OLGA is the industry-standard tool for dynamic simulation of multiphase flow of oil, gas, and water in pipelines and wells. To meet the challenges posed by construction of CCS-plants the simulator has been developed further with necessary upgrades, supported by experimental data validation. The simulator is presently used in most CCS-projects globally. The accuracy is good for single phase CO₂-transport.

In future CCS-projects it will be essential to be able to operate in the multiphase domain, either during special operations such as de-pressurization, or when injecting into low pressure depleted reservoirs. The possibility of multiphase transport will also likely be economically beneficial. Application of numerical simulation tools, such as OLGA, is essential for safe and effective design and operation of CCS-plants. Use of data from two multiphase flow laboratories acquired under relevant conditions for future CCS-solutions has identified gaps in the OLGA simulator within three main areas:

(1) Stability and robustness,
(2) Degree of accuracy of the thermodynamic description of CO₂ with impurities, and
(3) Degree of applicability of the flow model for CO₂ dominated pipeline systems.

The project aims to fill these gaps such that OLGA will cover the need for a simulation tool for transient multiphase flow in future CCS-projects. The simulator shall facilitate decision making that secures efficient and sustainable long term technical solutions, reduces the risk of undesirable events, like CO₂ escaping to the surroundings, as well as ensuring low capital and operational expenditures. OLGA shall be further developed to meet the demands of robust and accurate simulation of transport and injection of two-phase pure CO₂ and CO₂ with impurities. OLGA will be improved such that the simulator achieves the same level of robustness and accuracy for future CCS as in today’s oil and gas activity. In projects with small financial margins, it will be crucial to have well qualified simulation results as basis for decisions during development and operation.

Project activities include the following:

• Development and improvement of numerical solution schemes
• Upgrade of relevant thermodynamic and hydraulic flow models

The project objectives shall be validated through testing of realistic simulation scenarios and assessment of stability and robustness. Improved schemes and models are verified against available measurements from laboratories and fields.