FIELD-EVALUATION OF A MULTIPHASE METER IN WELL-TESTING OPERATION

This paper describes the evaluation results on the measurement accurac y and long-term operation of a multiphase meter used for well testing. The test was conducted by Chevron at its Lost Hills field in Californ ia. After many years of development work, several multiphase meter man ufacturers have begun to offer their meters commercially for productio n operation. In this paper, commercial multiphase meters are first bri efly reviewed based on the methods that those meters use to handle the fluid flow. The multiphase meter selected for this application was ma nufactured by Accuflow Inc. It uses the compact separation approach in handling the oil/gas/water flowstream by first separating the gas fro m the liquid stream and then measuring the gas and oil/water separatel y. The Accuflow system was installed at a gauge station in January 199 6. It was designed to test wells that have productions ranging approxi mately from 100 to 400 bbl of fluid per day, with a high water cut (40 to 90%), and up to 200 Mcf/D of gas. For accuracy testing, the multip hase meter was piped in series with a test separator at the gauge stat ion. Production from selected wells, covering a wide range of flow rat es, water cuts, and gas volume fractions, flowed through the multiphas e meter first and then through the test separator, which enabled compa rison of the new meter's performance and accuracy with an existing ref erence. Additional tests also were conducted to compare results with a test tank at the site. The paper also discusses other operational asp ects of the multiphase meter such as equipment maintenance and sand ac cumulation. Overall, satisfactory performance of this multiphase meter was observed, and additional units have been installed at the Lost Hi lls field.