Simultaneous measurement uncertainty reduction and proppant bank height control of hydraulic fracturing

Abstract

In hydraulic fracturing, higher fracturing fluid injection rates can trigger increased stress, thereby creating more microseismic events; particularly, simultaneously occurring multiple microseismic events can reduce measurement errors. This suggests a new state and output estimation scheme that utilizes the dependence between the fracturing fluid injection rate (i.e., manipulated input) and measurement errors. Motivated by this, we propose a novel control framework for measurement uncertainty reduction while achieving the original control task of proppant bank height control in hydraulic fracturing. Initially, using the simulation data from the high-fidelity model of hydraulic fracturing, a reduced-order model is constructed to design a Kalman filter. Then, a model-based feedback control system is proposed to regulate the uniformity of proppant bank height along the optimal fracture length and achieve accurate state and output estimation by manipulating the fracturing fluid pumping schedule that includes the fracturing fluid injection rate and proppant concentration at the wellbore.