Oscillating Back Pressure Regulator (OBPR) for High-Pressure Core Flooding

Abstract

The challenge in the core analysis industry is the availability of a versatile back pressure regulator (BPR) that can operate efficiently at ultra-low or no-flow conditions at very high pressure. The existing models of back pressure regulators are limited to a specific range of operating conditions, automation, and robust core flooding environment. In this work, we developed an initial stage prototype of an Oscillating BPR (OBPR), emphasizing detailed instrumentation and implemented automation. The critical component in an OBPR is the valve that needs to operate within defined close and open position based on the feedback received from an encoder rather than the oscillation created by the flow system or by using a square wave oscillator. The paper investigates the static and dynamic characteristics of the newly designed OBPR instrument. The paper discusses the graphical programming LabVIEW software used to create the feedback control loop using the PID controller. Initial results of the test run were done with the different core flooding systems like Water, Brine, and CO2. The study also included comparing OBPR pressure performance with the standard back pressure regulator in the market.