Type / Description
- Market standard VRT designs, based only on 30-minute residence time criteria resulted in:
- Larger vessels to cope with increased processing capacity requirements leading to higher total installation costs
- Poor hydraulic and thermodynamic performance leading to frequent operational issues such as flooding, liquid carry-over into the gas stream, poor liquid degassing, and high RVP crude oil
Challenge
- Simplify the VRT model to reduce total installation costs
- Address hydraulic and physical issues observed in market standard equipment
- The vessel should consist of pipes instead of heads and shells
- The new design should consistently achieve the stringent RVP specs
Project Development
- The main physical phenomena involved in the degassing process of crude oil were figured out and analyzed
- A vertical design was developed based on equipment familiar to operators and an optimized horizontal model was developed as well
- A spreadsheet was provided with sizing calcs for two alternative vessel configurations
- Mechanical drawings were provided for vessel fabrication
Outcome
- The new minimalistic VRT standard addressed the hydraulic and physical issues and reduced the total installation costs
- The provided design maximized the liquid film area exposed to the lowest pressure to facilitate degassing
- The enhanced gravity separation inlet favored the liquid degassing minimizing foaming
