Oil and Gas

Multiphase Flow

Multiphase flow means that a mixture of gases, liquids and/or solid particles flow together as a mixture, but without being completely dissolved in each other.
Contact

Nossen, Jan

Deputy Head of Department

 

Such flows are everywhere:

  • In the atmosphere
  • In the food industry
  • In cooling systems
  • In the process industry
  • In oil and gas reservoirs
  • In pipelines

Multiphase flow in pipes

In oil and gas production, multiphase flow often occurs in wells and pipelines because the wells produce gas and oil simultaneously. This is called two-phase flow. In addition to gas and oil, water is also often produced at the same time. This is called three-phase flow.

Subsea oil and gas fields save billions in investments

In the North Sea, the oil companies previously often built large production platforms standing on the sea floor, equipped with process facilities separating gas. oil and water. The gas was sent to market in one pipeline, while the oil was shipped directly or sent to shore in another pipeline. Today this is usually too expensive. Instead the operators often choose subsea developments where the untreated well stream is sent directly from a subsea template to an existing platform or to shore in one multiphase pipeline. In cases where a subsea development with multiphase transport is feasible, billions may be saved by dispensing with costly platforms.

Design and operation of multiphase transportation systems (flow assurance)

Multiphase transportation implies many new challenges:

  • Under unfavourable conditions, oil and water may flow in large batches (slug flow) which can disturb the receiving facilities
  • Oil and water may form emulsions which give high pressure losses and reduced production
  • Wax and hydrates (an ice-like substance) may precipitate and block the pipe
  • Unfavourable water chemistry may lead to fatal corrosion attacks piercing the pipe
Before commissioning a field, it is important to be able to predict possible production problems and to predict flow patterns and pressure losses as accurately as possible so that pipelines and process plants may be designed optimally.