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BR-102022012728-B1 - UNIT FOR VISUALIZING THE RESTART OF TIME-DEPENDENT FLUID FLOW

BR102022012728B1BR 102022012728 B1BR102022012728 B1BR 102022012728B1BR-102022012728-B1

Abstract

UNIT FOR VISUALIZING THE RESTART OF TIME-DEPENDENT FLUID FLOW. The present invention relates to a unit for visualizing the restart of time-dependent fluid flow comprising two hydraulically connected storage tanks (1, 2); two auxiliary tubes (3); a main tube (4) between the storage tanks (1, 2) and between the auxiliary tubes (3); a viewing box (15); a pressurization system (20); data acquisition software; and a particle image velocimetry (PIV) system (8); wherein the main tube (4) is made of a transparent acrylic material that allows visualization of the fluid within it; wherein the viewing box (15) encompasses the main tube (4) and allows its visualization; and wherein the unit visualizes the restart of time-dependent fluid flow in transient regime.

Inventors

  • ANGEL DE JESUS RIVERA JIMENEZ
  • CEZAR OTAVIANO RIBEIRO NEGRAO
  • Rafael Mendes
  • DOUGLAS TSUYOSHI HIROSE
  • ADMILSON TEIXEIRA FRANCO
  • YAMID JOSÉ GARCÍA BLANCO
  • EDUARDO GERMER
  • GUILHERME DOS SANTOS VIEIRA LIMA

Assignees

  • Petróleo Brasileiro S.A. - Petrobras
  • UNIVERSIDADE TECNOLÓGICA FEDERAL DO PARANÁ

Dates

Publication Date
20260317
Application Date
20220624

Claims (15)

  1. 1. Unit for visualizing the restart of time-dependent fluid flow characterized by comprising: two hydraulically connected reservoir tanks (1, 2); two auxiliary tubes (3); a main tube (4) between the reservoir tanks (1, 2) and between the auxiliary tubes (3); a viewing box (15); a pressurization system (20); data acquisition software; and a particle image velocimetry (PIV) system (8); wherein the main tube (4) is made of a transparent acrylic material that allows visualization of the fluid within it; wherein the viewing box (15) encompasses the main tube (4) and allows its visualization; and wherein the unit visualizes the restart of time-dependent fluid flow in transient regime.
  2. 2. Unit according to claim 1, characterized in that the two reservoir tanks (1, 2) are hydraulically connected to the main pipe (4) through auxiliary pipes (3) that allow the fluid to flow from the reservoir tanks (1, 2) to the main pipe (4).
  3. 3. Unit, according to claim 1, characterized in that the tanks (1, 2) also have an adapter (16) on the top cover of each tank, allowing the entry of compressed air so that the fluid is pressurized and flows through the tubes from one tank to the other; a pressure gauge (12); a pressure relief valve (11); a level indicator (9) installed on the side of each tank (1, 2) to view the fluid level inside the tanks (1, 2); and a thermocouple (7) fixed inside each reservoir tank (1, 2) to record the temperature at which the system is during the flow restart tests.
  4. 4. Unit according to claim 1, characterized in that the main tube (4) is made of polymethyl methacrylate (PMMA), is immersed in water and is located inside the viewing box (15).
  5. 5. Unit according to claim 1, characterized in that the pressurization system (20) is composed of the pressure regulating valve (10), the solenoid valves (14), the pressure gauges (12) and the pressure relief valves (11).
  6. 6. Unit according to claim 5, characterized in that the pressure regulating valve (10) and the solenoid valve (14) are located upstream of the reservoir tanks (1, 2) and the pressure gauge (12) and the pressure relief valve (11) are installed on the top cover of each reservoir tank (1, 2).
  7. 7. Unit according to claim 6, characterized in that the pressure regulating valve (10) is adapted to pressurize the fluid in the tanks.
  8. 8. Unit according to claim 6, characterized in that the two solenoid valves (14) installed upstream of each reservoir tank (1) and (2) allow pressurization of only one reservoir tank and block pressurization of the other reservoir tank.
  9. 9. Unit according to claim 6, characterized in that the two solenoid valves (14), installed upstream of each reservoir tank (1) and (2) and after the pressure regulating valve (10), allow flow in both directions.
  10. 10. Unit, according to claim 1, characterized in that the auxiliary tube (3) also has two pressure sensors (5) to measure the operating pressure and/or the pressure variation at the restart of the flow and thus estimate the shear stress on the wall (Tw) •
  11. 11. Unit, according to claim 1 or 2, characterized in that the auxiliary tubes (3) also have two shut-off valves (6) installed at the inlet and outlet of the auxiliary tube (3) to control the flow during fluid restart tests.
  12. 12. Unit, according to claim 1, characterized in that the main tube (4) also has four thermocouples (7) fixed to its exterior and internally to the viewing box (15) to record the temperature of the restart of the flow.
  13. 13. Unit according to claim 3, characterized in that the pressure relief valves (11) installed on the lid of each reservoir tank (1, 2) are for depressurizing the system.
  14. 14. Unit according to claim 1, characterized in that the data acquisition software monitors and records the pressure and temperature values given by the pressure sensors and thermocouples (7).
  15. 15. Unit according to claim 1, characterized in that the system's image processing and handling software (VIP) (8) calculates velocity profiles and gradients, wherein the yield stress limit is calculated directly from the velocity profiles by means of its first derivative (velocity gradients).

Description

Field of invention [001] The present invention is situated in the technical field of petroleum production processes, more specifically, in the area of lifting and flow technologies. [002] The present invention describes a unit for studying technical information for the fluid flow process after interruptions in production or restarting the flow of gelled drilling fluids after stops in the drilling process. Fundamentals of the invention [003] Fluid gelation is a highly relevant problem in several industrial sectors, particularly for the offshore oil and paraffinic oil industry where materials with complex properties are transported through long pipelines. [004] In ultra-deepwater fields, a more common scenario in Brazil, extensive production lines positioned on the seabed imply significant challenges regarding flow assurance. Due to the length of the pipelines, the oil from the reservoirs at high temperatures is cooled, releasing heat into the marine environment. [005] The reduction in temperature results in a decrease in the solubility of paraffin in petroleum. Below a certain temperature, called the crystallization temperature, precipitation and deposition of paraffin crystals occurs on the inner walls of the pipelines. [006] The precipitation of crystals in the flow alters the behavior of the oil, which begins to behave like a suspension, evidenced by a significant increase in its viscosity. [007] In the event of production stoppages, the crystals suspended in the oil can interlock and gel the material in the pipelines, making it difficult or even impossible to restart the flow, especially when these stoppages are of long duration. [008] To resume the flow of gelled fluids, it is initially necessary to break the gel structure, which requires a restart pressure higher than the steady-state operating pressure. This minimum pressure for resuming oil flow is correlated with the yield strength (YS) of the material, that is, a critical stress value below which no flow occurs. [009] In flows involving pasty materials or suspensions, however, the flow transition (rupture) is often associated with the wall sliding phenomenon, which makes estimating the pressure at the start, or restart, of the flow even more complex. [0010] In the case of gelled oil, wall slip manifests itself in a range of low-magnitude shear forces (shear stress), such that wall slip and creep transition are coupled and directly related to the velocity gradients that arise during the transient process of gel structure breakdown. Therefore, these factors influencing the magnitude of the flow restart pressure must be analyzed and well understood, because when the pressure is overestimated it can result in overly robust pipeline designs, which could make them unfeasible. [0011] Several methods for evaluating the onset of flow of gelled fluids in pipelines have been devised, ranging from studies that assess the hydrodynamics of the flow using experimental units and descriptive methods, to studies that evaluate the use of additives that help improve the fluidity of this type of fluid. [0012] US patent 3,502,103, owned by Shell Oil in 1970 and now in the public domain, for example, presents a unit that uses a less dense liquid to form a lubricating layer between the pipe wall and the oil to reduce friction losses when pumping mineral oil through the pipe. The gelled oil moves in the form of a plug through the center of the pipe, and water (the lubricating fluid) forms a layer between the oil and the pipe wall, facilitating flow. This document allowed for the analysis of the transport of very rigid hydrocarbons through pipelines. [0013] US Patent 4,056,335 owned by United Steel Corporation and EP Patent 0322958 B1 owned by Shell Internationale, both also in the public domain, describe experimental units for studying the onset of flow of extremely viscous crude oils from offshore reservoirs. The experimental units were equipped with submersible pumps to simulate field conditions. An important aspect of these two inventions is that water is injected and mixed with crude oil within a cavity at the base of the submersible pump, thus decreasing the effective viscosity of the fluid and also controlling the operating temperature of the pump. The two units differ only in that the first uses a submersible pump driven by a conventional surface rotor and the second a submersible pump rotor. [0014] US patent 5,348,094, owned by the French Petroleum Institute, also in the public domain, discloses an experimental unit and a method for displacing a high-viscosity fluid containing a certain proportion of gas, wherein the pump is connected to the lower end of a tubular column at the bottom of a well to move the fluid from this position to a production zone on the surface. [0015] Petrobras patent BR 102016019029-0 discloses a system and method for restarting flow in pipelines that allows the degradation of the gelled fluid without causing high pressure peaks in the pipel