Rock-Flow Cell: An Innovative Benchtop Testing Tool for Flow Assurance Studies

Abstract

Flow assurance is a critical component in the design and operation of robust oil/gas production systems. Undesired precipitation of solids (gas hydrates, wax, asphaltenes, scale) reduces the production rate and often leads to costly and hazardous disruptions. Many experimental and modeling efforts have been made to build knowledge of managing such risks. However, a major difficulty is to transfer the laboratory data to the field conditions. We introduce a new experimental system, the rock-flow cell, which is compact and requires fewer resources to build and operate. This system can readily achieve different flow regimes by controlling the liquid loading, water cut, and rocking angle/speed. A sight glass visualizes when, where, how, and how much solid forms and precipitates out. Gas hydrate formation tests with anti-agglomerants are presented to demonstrate the capabilities. The rock-flow cell is an innovative testing tool for flow assurance studies by properly capturing thermohydraulic conditions in actual flowlines.

Chemically Influenced Self-Preservation Kinetics of CH4 Hydrates below the Sub-Zero Temperature

“…Parameters associated with the experimental setup, such as rock angle, rock frequency, solution volume, type of rocking ball material, and operating conditions that affect the performance of the rocking cell, have been studied in detail [48]. Other advantages include the small sample volume and standardization, which facilitates comparing research data between groups [49].…”

Advancing Laboratory Characterization and Qualification of Additives for Hydrate Slurry Flow in Multiphase Systems

“…From the experimental results of these three comparative SH tests, the rock-flow cell demonstrated its capability to characterize the effects of the degree of subcooling and salinity on hydrate slurry flow by visual observation of hydrate aggregation, deposition, and bedding and quantification of the pressure drop that is translated into water conversion. While there are many other experimental parameters affecting hydrate slurry flow, such as liquid loading, water cut, fluid properties, flow regimes, additive type/concentration, and gas composition, , the rock-flow cell can be used as an effective lab and bench-scale testing setup for LDHI-AA qualifications.…”

“…Figure shows a schematic of the rock-flow cell experimental system used for all the tests. Full details on the rock-flow cell system are well described elsewhere. , Briefly, the stainless cell with a 2 inch inner diameter and 3 feet length can sustain operating pressures up to 100 bara. A cooling jacket that covers the length of the cell is connected to a refrigerating chiller for temperature control.…”

“…Schematic of the lab-scale rock-flow cell setup used for the hydrate tests. Reproduced and reprinted with permission from Ref . Copyright 2020 American Chemical Society.…”

“…The recently developed rock-flow cell is capable of a more rigorous and representative test for LDHI-AA qualification as it can better reproduce the shear and dispersion of the phases as expected in pipe flow. 11 Even though the rock-flow cell has several limitations in terms of how flow is induced, the absence of gas flow, and relatively low liquid velocity, it can still better capture the shear and phase dispersion under the conditions that would often be encountered in the field in terms of liquid loading, water cut, and gas to oil ratios. 12 In this paper, we demonstrate the capabilities of the rock-flow cell as a robust experimental testing tool for LDHI-AA qualifcations.…”