Incorporation of Sustainability and Economic Considerations in Process Control of Hydraulic Fracturing in Unconventional Reservoirs
Abstract
Typically, the term shale oil refers to natural oil trapped in rock of low porosity and ultralow
permeability. What has made the recovery of shale oil and gas economically viable is the
extensive use of hydraulic fracturing. Research on the relationship between the distribution of
propping agent, called proppant, and well performance indicates that uniformity of proppant bank
height and suspended proppant concentration across the fracture at the end of pumping determines
the productivity of produced wells. However, it is important to note that traditional pumping
schedules have not considered the environmental and economic impacts of the post-fracturing
process such as treatment and reuse of flowback water from fractured wells.
Motivated by this consideration, a control framework is proposed to integrate sustainability
considerations of the post-fracturing process into the hydraulic fracturing process. In this regard,
a dynamic model is developed to describe the flow rate and the concentration of total dissolved
solids (TDS) in flowback water from fractured wells. Then, a thermal membrane distillation
(TMD) system is considered for the removal of TDS. A multi-objective problem is formulated to
optimize the entire superstructure that consists of hydraulic fracturing, storage, transportation, and
water treatment, minimizing annualized cost from recovered water per period and the water
footprint of the process. The capabilities of the proposed approach are illustrated through the
simulation of different scenarios that are performed to examine the effects of water availability on
the productivity of stimulated wells. Finally, the impact of flowback water generation is evaluated
using TRACI, a tool for the reduction and assessment of chemical and other environmental
impacts.
Citation
Etoughe, Priscille Irene Flavienne (2018). Incorporation of Sustainability and Economic Considerations in Process Control of Hydraulic Fracturing in Unconventional Reservoirs. Master's thesis, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /174129.