As part of a joint industrial initiative, Texas A&M University graduate researcher Gabriel Tatman used 3D printing to replicate cracks that reveal proppant and diverter activity.
Over time, the oil and gas industry has adjusted the proppants and diverters used in fracture operations to boost oil recovery in shale reservoirs. 3D printing technology helps to address this problem. However, the attempts are based on educated guesses because proppant and diverter activity is impossible to see because it occurs completely out of sight downhole.
As part of a joint industrial initiative, Texas A&M University graduate researcher Gabriel Tatman used 3D printing to replicate cracks that reveal proppant and diverter activity. His new use of clear models derived from actual rock fracture data revealed these previously hidden characteristics, resulting in the unique ability to reproduce fracture flow tests in minute detail.
Texas A&M University and the Colorado School of Mines collaborate on the research, which includes actual proppant transport trials. The goal is to find the conditions that lead to optimal proppant placement, as well as which proppant concentrations and kinds operate best in different rock geometries. This will boost hydraulic fracturing efforts in the oil recovery industry.
Oil recovery in shale reservoirs often begins with hydraulic fracturing, in which high-pressure fluid is blasted into the rock formation to fracture or break the shale. Proppants, which are varying sizes of sand grains, are flushed down in a fluid slurry to keep these cracks open when the high pressure is dropped, allowing oil and gas to flow to the well. Diverters, which are chemical or mechanical components that may be dissolved or recovered later, are occasionally injected to deliberately obstruct primary slurry routes, forcing proppants into other channels to form complex fracture geometries. Typically, the procedure goes unnoticed, but 3D printing technology is working to change that.
The ability to observe actual proppant behaviour is remarkable, but the technique also applies 3D printing to fracture conductivity in a novel way.
Previously, researchers created laboratory-scale equipment to analyse how well proppants allow oil and gas to flow through fissures, a phenomenon known as conductivity. Nonetheless, the equipment was typically built with smooth walls, despite the fact that genuine rock fracture surfaces are highly uneven.
With today’s technology, rough artificial fracture surfaces may be easily manufactured in detail using 3D printing. The disadvantage is that 3D printing resins are not strong enough for studies that require rock-like strength. Tatman’s 3D printing are thus employed as moulds to produce artificial rock structures out of high-strength cement capable of capturing complicated surface patterns. And because these artificial samples may be created indefinitely from moulds, they provide constant and repeatable test bases for more accurate study outcomes.