The deep water gas development offshore Tanzania in East Africa is characterized by water depth of up to 2600 meters combined with a seabed consisting of deep, large scale canyons and steep inclinations towards the shore. The reservoir fluids are very dry and the pipeline flow is typically low liquid loading conditions at which multiple holdup solutions exist. Previous experience has shown that the OLGA model is not predicting well at these conditions and that very little experimental data exist for such conditions. Hence the experimental "Large Scale Liquid Loading Two-phase Flow Tests" campaign was carried out at the SINTEF Tiller large scale test facility, followed up by the "Core Model Evaluation and Flow Assurance Risk Study" with Schlumberger SPTC.
This presentation gives an overview of the Tanzania deep water gas development with focus on the flow assurance challenges relates to a Subsea to Beach concept. The background, motivation and scope of work for the two studies "Large Scale Low Liquid Loading Two-phase Flow Tests (SINTEF)" and "Tanzania Core Model Evaluation and Flow Assurance Risk Study" (Schlumberger SPTC) are given, while the results are presented in detail in separate presentations.
The Tanzania Gas Project (TGP) is located in Block 2 approximately 100km offshore Tanzania in East Africa (ref Figure 1). Statoil Tanzania AS is the operator in Block 2 with 65% interest with ExxonMobil as a partner with 35% interest. Locations of the Block 2 discoveries are shown in Figure 1. The objective of the project is to develop the core area of Block 2 by producing gas offshore, transporting it to shore and feeding an onshore Joint Venture (JV) Liquefied Natural Gas (LNG) plant. The onshore JV is between the operators of Blocks 1, 2, 3 and 4. BG Group (BG) is the operator of Blocks 1, 3 and 4. As of 1Q 2015, eight reservoirs have been discovered in Block 2: Zafarani, Lavani Main, Lavani Deep, Tangawizi, Mronge, Mdalasini, Giligiliani and Piri.
This paper gives an overview of the Tanzania deep water gas development with a focus on the flow assurance challenges relating to a Subsea to Beach concept, and then especially related to multiphase flow modelling. The reservoir fluids are very dry and the pipeline flow is typically low liquid loading conditions at which multiple holdup solutions exist. Experience has shown that the "standard" OLGA model is not predicting well at these conditions (ref Figure 11) and that very little experimental data exist for such conditions. The background, motivation and scope of work for the two studies "Large Scale Low Liquid Loading Two-phase Flow Tests (SINTEF)" and Tanzania Core Model Evaluation and Flow Assurance Risk Study (Schlumberger SPTC) are given, whilst the results are presented in detail in separate papers (ref /14/, /15/, /16/ and /17/), each presenting in detail the studies that have been carried out as part of the Tanzania flow model verification work.
