An Inventory and Engineering Assessment of Flared Gas and Liquid Waste Streams From Hydraulic Fracturing in the USA

Abstract

Purpose of Review In this study, we compile and curate data from 2012, 2013, and 2014 on flared gas and generated wastewater associated with hydraulic fracturing operations in seven major shale regions of the USA. In the process, we provide an historical perspective of the management practices of flared gas and wastewater prior to the decline in oil prices in 2015. An engineering assessment of the technical potential for repurposing the energy from flared gas for treating hydraulic fracturing wastewater is also considered. Recent Findings The seven shale regions were evaluated using mass balances and thermodynamic analysis of the wastewater and flared gas volumes using data compiled from state, federal, and private sources for each region. After curating the publicly available data, we determined that from 2012 through 2014, the Bakken, Marcellus, Utica, and Niobrara flared between 2 and 48 times the amount of natural gas needed to provide energy for treatment of the wastewater produced from the oil and gas industry. The Permian Basin, Eagle Ford, and Haynesville did not have sufficient flared gas to treat the wastewater produced in each respective region and thus would need other energy sources for water and wastewater treatment. Summary The findings indicate that novel approaches to managing existing resources and waste streams might have the potential to improve the environmental footprint and economic productivity of select oil and gas sites.

Sustaining Water Resources: Environmental and Economic Impact

“…Rather than flaring, the gas could be used as an energy source to power water treatment facilities, thereby converting two waste streams into one or more valuable byproducts: most importantly clean water 64,65 and potentially minerals such as lithium. 66 Alternatively, analogous to energy recovery from municipal wastewater the excess gas and produced water could be used as an energy source and feedstock, respectively, to enable the production of biofuels and protein rich animal feed, e.g., algae. 67 It is also worth considering whether oil and gas combustion could be a source of water.…”

“…For instance, during the process of producing oil and gas, operators flare excess gas and dispose of contaminated water brought to the surface. Rather than flaring, the gas could be used as an energy source to power water treatment facilities, thereby converting two waste streams into one or more valuable byproducts: most importantly clean water , and potentially minerals such as lithium …”