Well Output Measurement Using the Dual Differential Pressure Method

Abstract

In 2019 Landsvirkjun, in cooperation with academic and industrial partners, launched a project geared towards finding a practical method for measuring well output in real-time. A full-size production line was assembled and connected to wells that allowed the testing of several different potential measurement methods at a wide range of realistic flow conditions. In this paper the experiment, conducted in conjunction with Tek DPro Flow Solutions, is described along with its main conclusions with regards to the orifice meter dual differential pressure (DDP) method. The DDP method is very practical as it is based on a standard setup for differential pressure measured across an orifice plate (commonly installed at geothermal wells), with an added pressure port further downstream of the orifice plate. Using the signals from these three pressure ports, our results indicate, one can determine the steam quality, steam, water, and total flow with reasonable accuracy. The observed correlation applies for a wide range of flow conditions commonly occurring in high-enthalpy geothermal fields. Once the steam quality has been determined the total flow and enthalpy can be computed based on previously known formulations.