Subsea Surveillance Focal Point - Appomattox FPS (Floating Production & Storage) Platform.
Monday, April 15, 2019
Solid phase formation in subsea production many times constrains (i.e. flow impairment or plugging) both the design and operation of the systems. Moreover, studying the solid-fluid equilibria and mass transport phenomena can lead to more robust engineering approaches. Asphaltene, paraffin and hydrates are three solids that present distinct pressure- temperature phase diagrams. Detailed methods for predicting phase behavior and measuring precipitation are employed to better understand the impact in the field. However, precipitation is necessary but not entirely sufficient to impact a design or operations. Understanding other thermal-hydraulic driving forces (e.g. wall shear stress, thermal gradients, pressure drops, etc.) better defines the net effect on the subsea production system. Furthermore, use of chemical injection to prevent or inhibit solid formation is a viable option in the field but the chemistry's effectiveness is not always fully understood. This seminar gives an overview of typical asphaltene, paraffin and hydrate phase behavior, discusses thermodynamic equilibrium prediction methods, details known solid deposition and plugging mechanisms, describes applicable experimental methods, and summarizes current chemical mitigations for solids.