Multiple Application of Multi-Energy Gamma Ray Venture Type Multiphase Flowmeter in Giant Karachaganak Gas Condensate Field

Abstract

The objective of this paper is to demonstrate multiple application of multi-energy gamma ray venture type multiphase flowmeter (MPFM) trial campaign in Karachaganak gas condensate giant carbonate field, operated by KPO B.V. The results of MPFM that was included into surface well test spread, to verify its performance, was compared against portable test separator and plant production testing facilities (control separator, flowmeters) and manual sampling results. MPFM from other vendors historically failed to deliver accurate production measurement mainly due to complexity of reservoir fluid in Karachaganak field. To ensure the MPFM considers this complexity, PVT samples were taken to provide laboratory data for PVT model of the MPFM to ensure sufficient quality of PVT data and compare against PVT model inside MPFM. First application of MPFM was during clean-up of the well prior handover well to production. Using MPFM helped to improve the quality during data acquisition. This information was critical for the well to be accepted by processing facility it is hooked-up to and to define optimal operating regime. Validation of BS&W, GOR and rates in unstable (foaming, carry over) and transient phase of production using MPFM has shown practical advantages. Another application was for water sampling loops to measure water cut and production rates. KPO has had challenges with inaccurate water cut measurement due to the limitations of existing test separators. A recent approach of performing fluid sampling (sampling loop) at the well head proved to be reliable source of measurements. In addition, the MPFM in combination with the test separator has been used to further improve the quality of the measurements of each phase. The third MPFM application had been with high gas-volume-fraction (HGVF) pumps, that helped to produce from low reservoir pressure, low GOR and high water cut wells. The operational range of HGVF pump was limited to maximum 75-80% of gas-volume-fraction (GVF). MPFM measures GVF in real-time to ensure HGVF pump operates in optimum operational range by managing the surface flow conditions. With current limitations of test separators in Karachaganak field and due to complexity of the gas-condensate fluid, the use of MPFM brings additional quality in the measurements (rates, water cut and GOR) which is crucial for field production optimization, reservoir management and short and long term forecasting.