Theoretical Study on the Influence of the Multistage Throttling Structure during the Venting Operation

Abstract

The venting operation is a primary measure to mitigate overpressure in CO₂ transport pipelines. It involves intense oscillations and the threat of low temperatures arising from the throttling effect. Multistage throttling structures have been proven to effectively enhance the stability of the system, and the objective of this study is to explore the impact of multistage throttling structures on the pressure and temperature within the throttling structure using a one-dimensional model. The results indicate that by appropriately setting the numbering of valves, valve openings, and diameter of throttling pipes, multistage throttling can effectively elevate the temperature of the throttling structure. However, it is noteworthy that achieving the avoidance of low-temperature phenomena comes at the expense of reducing the pressure drop rate within the main pipeline. Therefore, the practical application should consider a balanced approach to both the low temperature in the throttling structure and the overpressure in the main pipeline.