27 CHAPTER IV SIMULATION RESULTS IV.1. Fluid PVT Simulation PVT data from the " LAB " field is this study's base case. Based on the PVT analysis, CO 2 stream has a purity of 99.7% CO2, with the rest being impurities; then, the case is constructed for low – high scenarios. The PVT data will be developed into several scenarios to describe the best and worst conditions of CO 2 dehydration in reducing the water content of CO 2 streams. The phase envelope for each composition of CO 2 mixtures was determined through the utilization of the Robinson Advanced Equation of State (PRA) in the multiflash software, employing the PVT simulation in order to derive the phase envelope and critical point through the utilization of P-T analysis. Peng-Robinson Advanced EOS is considered the most accurate for utilization in the "LAB" Field PVT simulation, primarily because it accounts for the inclusion of impurities, specifically water content, within the CO 2 mixture. The following is a summary of the scenarios and the phase envelope that were employed with KBC Multiflash software. Table 4.2. PVT Simulation Scenario Fluid Type Composition Critical Pressure (bar) Critical Temperature (�q�qF) Case A Fluid (a) Pure CO2 73.15 87.075 Case B Fluid (b) CO2 + 0.0122% Water 74.16 88.440 Case C Fluid (c) CO2 + 0.5% Water 74.45 89.195 28 (A) (B) (C) Figure 4.4. Phase Envelope for (a) Composition A, (b) Composition B, and (c) Composition C The simulation results indicate an upward relationship between the water content in the CO 2mixture and the critical point of the mixture, indicating that an increase in water content leads to a rise of the critical point. The augmentation of the critical point significantly impacts the transport conditions as it necessitates elevated pressure and temperature for attaining the supercritical state of the CO 2mixture. Moreover, if the design pressure and temperature fail to attain the supercritical state of the CO 2mixture, the potential for multiphase flow arises, posing significant risks during the transportation process. The transportation of carbon dioxide (CO 2) with multiphase flow appliances can give rise to various challenges. Among them is the formation of hydrates, which could block the pipeline. Also, the presence of turbulent flow can lead to corrosion and erosion, increasing the risk of pipeline leakage. Thus, ensuring the purification of CO 2is of utmost significance in order to attain of high purity CO 2, with low percentage of impurities and water content. IV.2. Pipeline Simulation with OLGA The OLGA transient dynamic simulator is used to model flow profile analysis in underwater pipeline systems over the time. Transient dynamic simulators are commonly favored over steady-state simulators in the context of investigating time- dependent phenomena, precisely capturing fluctuations, comprehending dynamic behavior, evaluating transient performance, and modeling intricate systems. Dynamic systems are better able to offer precise and comprehensive understandings of behavior, making them indispensable for capturing the temporary characteristics of diverse processes.