The occurrence of the severe slugging phenomenon in multiphase pipelines can cause serious and troublesome operational problems within the receiving process facilities. This paper describes: the pipeline operability studies on the Dunbar to Alwyn multiphase pipeline regarding riser-induced severe slugging; the control scheme selected to prevent this phenomenon; and the subsequent operating expe...

In order to prevent the severe slugging flow regime in multiphase transport pipelines, active feedback control is the recommended solution. Instead of elaborated models such as CFD and OLGA models, a simple dynamical model with few state variables is required in a model-based control system. We propose a new simplified dynamical model for severe slugging flow in pipeline-riser systems. The prop...

The current offshore oil & gas multi-phase production and transportation installations have big challenges related with the slugging flow: An unstable multi-phase flow regime where the flow rates, pressures and temperatures oscillate in the considered processes. Slug can be caused by different operating conditions and installation structures. The most severe slugs are often induced in long vert...

A highly transient flow regime called riser slugging can develop in pipelines from wellheads to separation tanks which introduces severe oscillations of pressure and flow rates in off-shore processes. Mitigation of the intensity of riser slugging may be achieved via anticipative control actions on valves positioned at the entrance and at gas/oil exits of the separators. In Phase 1, this work is...

Elaborated models such as those used for simulation purposes (e.g. OLGA simulator) cannot be used for model-based control design. The focus of this paper is on deriving simple dynamical models with few state variables that capture the essential behaviour for control. We propose a new simplified dynamic model for severe slugging flow in pipeline-riser systems. The proposed model, together with f...

Severe slugging is an unstable multiphase flow pattern occurs in a pipeline riser with low gas and liquid flowrates. It highly undesired practical operation because of the pressure mass oscillations induced. Riser outlet choking has shown effectiveness eliminating or reducing severity slugging. This work presents experimental numerical study on elimination severe riser-induced slug by means cho...