Wax Deposition in the Oil/Gas Two-Phase Flow for a Horizontal Pipe

Abstract

An experimental flow loop was designed and constructed to perform the wax deposition tests under the oil/gas twophase flow conditions in a horizontal pipe. The oil sample came from the Daqing Oilfield of China, which was characterized by high wax content. A particular local sampler was designed and installed at the outlet of the test section in the flow loop to make up for the drawback of no visual observation during the course of flow pattern verification, which is a good device to help verify the flow pattern by analyzing the inner flow situations at different circumferential and vertical positions. Using the local sampler in combination with analyzing the changes in pressure drop and liquid holdup, which is defined as the fraction of an element of pipe occupied by liquid at the same instant, flow patterns were identified and divided into two main categories, namely, the stratified flow and slug flow. Wax deposition tests were selected in the definite flow pattern regions instead of flow pattern transition regions. The effects of flow pattern characteristics on wax deposition were experimentally studied under the oil/gas two-phase flow conditions. The results show that liquid superficial velocity, gas superficial velocity, shear stress at the liquidÀdeposit interface, liquid holdup, and slug frequency do play an important role in wax deposition in the oil/gas two-phase flow. The wax deposition characteristics were experimentally obtained for stratified flow and slug flow. The experimental results in this study provide an experimental reference and insight for further study on wax deposition in multiphase flow, especially under the conditions that the oil sample is characterized by high wax content.' EXPERIMENTAL SECTION Experimental Sample. The experimental oil sample used in the study was a typical waxy crude oil characterized by high wax content and

Energy Equation Derivation of the Oil-Gas Flow in Pipelines

“…As wax deposition narrows the effective flow area of pipe, delivery capacity reduces, delivery pressure increases and if serious, blockage may occur. All of the thermo-physical parameters of multiphase mixture are linked with the temperature of the mixed fluid and the wax deposition rate is relative to the inner wall temperature directly bound up with that of the fluid [1]. Therefore, it is necessary to do some research on the temperatures of oil-gas flow and inner wall, which is crucial to security and economical operation of the pipeline system.…”

Computational study of wax deposition in pipeline

“…A lab-scale flow loop experimental result [13] is elected to be compared with the wax deposition model. A typical waxy crude oil 29.38% wt.% of wax content was used for the lab scale (ID=25.4mm, Length=24m) flow loop experiments.…”

Computational Flow Dynamic Simulation of Micro Flow Field Characteristics Drainage Device Used in the Process of Oil-Water Separation

“…Therefore, it is necessary to increase or decrease the weight of floating ball for purpose that the density of floating ball is within a reasonable limit [10,11]. Since the weight of floating ball has a great effect on drainage device, it should be watched closely at the change of oil quality and match the weight of floating ball in real applications.…”