Catalog Home Page

Environmental impact assessment and optimisation of onshore natural gas production and delivery

Bista, Sangita (2019) Environmental impact assessment and optimisation of onshore natural gas production and delivery. PhD thesis, Murdoch University.

[img]
Preview
PDF - Whole Thesis
Download (9MB) | Preview

Abstract

This research assesses the environmental impacts of developing shale gas. There is much uncertainty about the impacts of developing shale gas in Australia, as the country is at the early stages of exploration drilling. The majority of studies carried out to analyse the impacts of shale gas development have been specific to the USA. To address these uncertainties, detailed environmental impacts have been assessed using optimization modelling and life cycle engineering tools. The climate impact has been estimated for the domestic end-use scenario and the LNG export scenarios to Japan and China for electricity generation. The global warming potential (GWP100) ranges from 54 to 99 gCO2e /MJ with a central estimate of 72 gCO2e /MJ. The GWP 100, including land use change, is 230 g CO2e/MJ. The mercury (Hg) and radioactive element emissions (eg radon) are the major pollutants contributing to the Terrestrial Ecotoxicity Potential impacts. This research has compared the GWP 100 and GWP 20 for shale gas and the associated land use change for the first time. The ways to optimise the environmental outcomes and the cost of doing so are suggested through the hotspot analysis for best, worst and central cases.

Options for minimising the fresh water consumption from fracking have also been investigated with the cost of the produced water treatment and management for an Australian onshore natural gas well is estimated. The consumption of surface and groundwater is called the blue water footprint. The blue water footprint is 1.1L/MJ for the best, 1.67L/MJ for the central and 3.17 L/MJ for the worst cases. The green water footprint refers to the consumption of rainwater and topsoil water that does not become run off. The blue water use per MJ of shale gas extraction and delivery is 80% higher than the green water use.

The results of this research show that there is considerable scope to reduce the environmental impacts of fracking; although this has cost implications. Freshwater use and consumption is a prime concern for Australia in shale gas development using hydraulic fracturing. Therefore, the water stress index (WSI) per well is estimated. In water-stressed areas, the reuse of treated produced water from fracking in agriculture is one of the best management practices. The results also identify areas for improvement, which should be targeted, as well as recommendations for best practices and policy issues, for optimisation of future onshore shale gas developments.

Item Type: Thesis (PhD)
Murdoch Affiliation: School of Engineering and Information Technology
Supervisor(s): Jennings, Philip and Anda, Martin
URI: http://researchrepository.murdoch.edu.au/id/eprint/53054
Item Control Page Item Control Page

Downloads

Downloads per month over past year