ISSN 2394-3777 (Print) ISSN 2394-3785 (Online) Available online at www.ijartet.com International Journal of Advanced Research Trends in Engineering and Technology (IJARTET) Vol. 2, Issue 3, March 2015 All Rights Reserved © 2015 IJARTET 49 Multiphase Flow Metering in Oil and Gas Industry Saurabh Goswami Project Quality Manager, Chevron Corporation, Houston, TX, USA Abstract: This study summarizes the research work with reference to the multiphase flow metering in oil & gas industry. One of the challenging problems that the Oil & Gas industry has been dealing with for several years is accurate and reliable multiphase flow rate measurement in a three-phase flow. This type of flow is common while producing oil and gas wells. Transporting of crude oil and petroleum products to refineries, storage tanks, and other delivery points, metering of the fluid is essential for determining flow rate, volume, and cost. Crude oil is mixture of oil, gas, seawater and sand. Therefore, two- and three-phase metering systems require for metering. Conventional metering system is expensive and requires cumbersome test separators, high maintenance, and field personnel intervention. These conventional solutions do not lend themselves to continuous metering. Moreover, with diminishing oil resources, oil companies are now frequently confronted with the need to recover oil & gas from marginally economical reservoirs. In order to ensure economic viability of these accumulations, the wells may have to be completed subsea, or crude oil from several wells sent to a common central processing facility. Keywords: Oil & Gas, Metering, Offshore, Sub-sea. I. INTRODUCTION Conventional metering systems require the constituents or "phases" of the well streams to be fully separated upstream of the point of measurement. Multiphase metering techniques are developed to improve measurement limitations of conventional metering systems those require gravity based test separators. Flow metering is conducted routinely to monitor the flow rates from wells and forecast production. The flow metering data are used for reservoir management, production diagnostics and field allocation. To obtain accurate and consistent flow measurement from conventional well testing systems, the equipment requires high maintenance, field personnel intervention, and time to perform tests. Oil Companies are looking at the multiphase metering technology as a method for reducing the cost of flow metering and improving the quality of the flow metering. Since multiphase metering systems can operate without the need for phase separation, they can be made into compact and lightweight systems. The small footprints and lightweight advantages can produce significant savings, especially in offshore where size and weight may result in additional installation costs. II. MULTIPHASE FLOW METERING Conventional methods for metering oil and gas can now be replaced by a simpler, more economic technology known as MULTIPHASE FLOW METERING. Multiphase metering allows the measurement of gas; oil and water directly from the wellhead without separate them. This allows production to be measured directly from the wellhead, producing variable oil, water and gas streams, including a range of flow regimes from wet gas to gassy liquid. It eliminates the capital costs of the separator to measure oil & gas production as well as the tanks, valves, level sensors and flowmeters. It is no longer necessary to separate the flow regime in order to provide accurate measurements of oil, gas and water. III.MULTIPHASE FLOW Multiphase flow is a complex phenomenon which is difficult to understand, predict and model. Common single-phase characteristics such as velocity profile, turbulence and boundary layer, are thus inappropriate for describing the nature of such flows. Flow regimes vary depending on operating conditions, fluid properties, flow rates and the orientation and geometry of the pipe through which the fluids flow. The transition between different flow regimes may be a gradual process. The determination of flow regimes in pipes in operation is not easy. Analysis of fluctuations of local pressure and/or density by means of for example gamma-ray densitometry has been used in experiments and is described in the literature. In the laboratory, the flow regime may be studied by direct visual observation using a length of transparent piping. Descriptions of flow regimes are