Implementation of the Use of Drill Cuttings in Hydraulic Fracturing Related Operations

Abstract

The objective of this study was to implement the use of drill cuttings in hydraulic fracturing-related operations. Two specific uses were studied: the use of drill cuttings as propping agents in hydraulic fracturing, and the use of drill cuttings to quantify proppant concentration in hydraulic fractures when drilling through them.

Drill cuttings as propping agents were evaluated by conducting fracture conductivity experiments utilizing a modified API fracture conductivity cell and flowing dry nitrogen. Eagle Ford drill cuttings were used as received from the field (with oil-based mud drilling fluid) and washed and dried at room temperature to eliminate the drilling fluid. The drill cuttings were mixed at different concentrations with sand proppants and they were tested. Three different sand proppants were used to investigate the effect of the sand proppant in the mixture of drill cuttings and sand proppant fracture conductivity response. The results show that the closer the sand proppant size particle distribution to the drill cuttings, the better the results; the drilling fluid present in the drill cuttings can improve the fracture conductivities results in the mixtures evaluated while keeping it lower than 5 wt%.

Quantification of sand proppant in drill cuttings was evaluated using synthetic samples made with Eagle Ford drill cuttings. A light reflection method was developed to identify, under a microscope, the sand proppant particles and correlate their measured area with their mass. Knowing the total mass sample, it is possible to quantify the sand proppant mass in the drill cuttings. Blind samples were used to validate the method developed.

Finally, using a commercial hydraulic fracturing simulator, different hydraulic fractures in the Eagle Ford formation were simulated using a guar-borate cross-linked fracturing fluid to know the extent at which the sand proppant might be placed, and the distance at which a parallel well should be drilled to drill though the created hydraulic fractures and later quantify the sand proppant in the drill cuttings.