Shale Gas as an Option for the Production of Chemicals and Challenges for Process Intensification

Abstract

Shale gas is unconventional natural gas trapped or adsorbed in shale rock formations. As opposed to conventional natural gas, shale gas is difficult to extract because of the low porosity of the rock formations in which it is confined. This particular characteristic implied a high cost for the extraction of this gas, so that its production remained unfeasible until the development of more suitable extraction technologies, such as hydraulic fracturing and horizontal drilling [1]. Hydraulic fracturing is a stimulation technique used to increase the flow rate of gas and oil in low permeability reservoirs. This method consists in injecting high-pressurized fluids into the well to create fractures and maintain them opened to allow the flux of gas and oil [1, 2]. Hydraulic fracturing is generally combined with horizontal drilling to increase the area covered with a lower number of wells. These two technologies have led to an increase in the net production of natural gas in the United States (US) for more than a decade, which has been referred to as the shale gas revolution [1, 3]. The aim of this chapter is to give an overview of shale gas and its potential to produce value-added chemicals. This chapter addresses the following aspects: shale gas composition and places where deposits are located, effect of shale gas discoveries on natural gas prices, alternatives to produce chemicals from shale gas, and opportunities for process intensification.