Quantifying Erosion of Downhole Solids Control Equipment during Openhole, Multistage Fracturing

Abstract

Summary Proppant flowback from hydraulic fracturing is widespread and costly due to erosion and/or blockage of producing hydrocarbons as proppant may accumulate downhole. Several strategies have been applied to avoid or minimize proppant flowback, such as treatment optimization to maximize pack stability, resin-coated proppant, limiting drawdown, or letting it flow to deal with the consequences later. Another strategy to avoid proppant flowback is to install sand control equipment integrated into a sliding sleeve device (SSD) as part of the completion string. Although the presence of sand control equipment can mitigate the problem, it raises concern about erosion during fracturing. Although some installations have been successful, one is known to have experienced sand control failure. This study aimed to understand the effect of hydraulic fracturing on the erosion of completion equipment with an objective of improving the design to, as much as possible, prevent erosion failure. Computational fluid dynamics (CFD) was used to evaluate the root cause and identify more robust design solutions. The first step was to identify the most probable causes of sand control failure during multistage fracturing (MSF) in openhole (OH) horizontals. The as-is completion was then modeled, along with the screen, SSD, fracturing port, and OH isolation packer. Because the fracture location between two packers is unknown, and the fracturing port was located between multiple screen/SSD assemblies, annular flow across the assembly in both directions was considered. State-of-the-art CFD simulations were then performed on the installed design using actual flow conditions (rates, slurry properties, treatment time) from the failed installation. A new quasidynamic mesh (QDM) methodology was developed, which yielded more realistic (albeit still conservative) erosion-depth predictions. The results revealed areas for improving the design of key components of the 10-ksi-rated system, and CFD was rerun to confirm erosion resistance targets. Design modifications were implemented, and improved products were then manufactured and field tested. For a new 15-ksi design, particle–particle interaction was added to the CFD analysis. The results of the CFD analysis and field test are presented herein.

Review and Perspectives of Coated Proppant Technology

“…However, the compressive strength of quartz sand is low, and particle migration after crushing will lead to blockage of oil and gas channels and damage to equipment. 14 It is used in shallow wells with low closing stress. 15 The content of Al 2 O 3 in and sintering temperature of ceramic proppant can determine the density of ceramic proppant.…”

“…Since quartz sand proppant is formed naturally, it will not pollute the environment. However, the compressive strength of quartz sand is low, and particle migration after crushing will lead to blockage of oil and gas channels and damage to equipment . It is used in shallow wells with low closing stress …”

Multi-stage hydraulic fracturing technology in a well with horizontal working face

“…Moreover, in poorly cemented reservoirs the use of a smaller fraction proppant is preferable. Because the finegrained particles have been removed from the formulation, the packing of coarse-grained proppant gradually increases until it clogs and the permeability can decrease from 25 % till 35 % (Jin et al, 2019;Nicholson et al, 2021;Dikshit et al, 2021). The roundness or sphericity of the proppant granules determines their packing density in the fracture, the filtration resistance, and the degree of fracture of the granules under the action of rock pressure.…”

Forecasting the hydraulic fracturing efficiency when selecting wells for an event

“…Improving the efficiency of managing the development of oil deposits is based on the study and formalization of various processes aimed at extracting liquid hydrocarbons [1][2][3][4][5][6][7][8][9][10]. One of the given processes is the intensification of oil production with the application of impact on the bottomhole zone using hydraulic fracturing treatment.…”