The physics of extracting gas from shale formations

November 30, 2018

Extracting gas from new sources is vital in order to supplement dwindling conventional supplies. Shale reservoirs host gas trapped in the pores of mudstone, which consists of a mixture of silt mineral particles ranging from 4 to 60 microns in size, and clay elements smaller than 4 microns. Surprisingly, the oil and gas industry still lacks a firm understanding of how the pore space and geological factors affect gas storage and its ability to flow in the shale. In a study published in EPJ E, Natalia Kovalchuk and Constantinos Hadjistassou from the University of Nicosia, Cyprus, review the current state of knowledge regarding flow processes occurring at scales ranging from the nano- to the microscopic during shale gas extraction. This knowledge can help to improve gas recovery and lower shale gas production costs.

Extracting gas from shale has become a popular method in North America and has attracted growing interest in South America and Asia, despite some public opposition. Unlike conventional reservoirs, the pore structures of shale gas reservoirs range from the nanometric to microscopic scale; most natural gas reservoirs display microscopic or larger scale pores.

In this paper, the authors outline the latest insights into how the pore distribution and geometry of the shale matrix affect the mechanics of the gas transport process during extraction. In turn, they present a model based on a microscopic image obtained via scanning electron microscopy to determine how gas pressure and gas speed vary throughout the shale. The model is in agreement with experimental evidence.

The authors reveal that the orientation, density and magnitude of rock bottlenecks can affect the volume and flow in gas production, due to their impact on the distribution of pressure throughout the reservoir. The findings of their numerical simulation match available theoretical evidence.

N. Kovalchuk and C. Hadjistassou (2018), New Insights from Shale Gas Production at the Microscopic Scale, Eur. Phys. J. E, 2018, 41:134. DOI: 10.1140/epje/i2018-11741-5


Related Shale Gas Articles from Brightsurf:

Study reveals how to improve natural gas production in shale
A new hydrocarbon study contradicts conventional wisdom about how methane is trapped in rock, revealing a new strategy to more easily access the valuable energy resource.

Oil forecasting technique adapted for spreadsheets may cut shale operator costs
Porous rock containing oil and natural gas are buried so deep inside the earth that shale operators rely on complex models of the underground environment to estimate fossil fuel recovery.

Shale drilling activity linked to increased sexually transmitted infections in Texas, Yale study
Researchers at the Yale School of Public Health have found that rates of two sexually transmitted infections (STIs), gonorrhea and chlamydia, are 15% and 10% higher, respectively, in Texas counties with high shale drilling activity (''fracking''), compared to counties without any fracking.

Effects of natural gas assessed in study of shale gas boom in Appalachian basin
A new study estimated the cumulative effects of the shale gas boom in the Appalachian basin in the early 2000s on air quality, climate change, and employment.

Co-combustion of wood and oil-shale reduces carbon emissions
Utilization of fossil fuels, which represents an increasing environmental risk, can be made more environmentally friendly by adding wood -- as concluded based on the preliminary results of the year-long study carried out by thermal engineers of Tallinn University of Technology.

Atmospheric pressure impacts greenhouse gas emissions from leaky oil and gas wells
Fluctuations in atmospheric pressure can heavily influence how much natural gas leaks from wells below the ground surface at oil and gas sites, according to new University of British Columbia research.

Natural-gas leaks are important source of greenhouse gas emissions in Los Angeles
Liyin He, a Caltech graduate student, finds that methane in L.A.'s air correlates with the seasonal use of gas for heating homes and businesses

UNH research finds shale natural gas development impacting recreationists
Researchers at the University of New Hampshire took a closer look at shale natural gas energy development (SGD) and how it is affecting the experiences of outdoor recreationists, like hikers and campers.

A voracious Cambrian predator, Cambroraster, is a new species from the Burgess Shale
Palaeontologists at the Royal Ontario Museum and University of Toronto have uncovered fossils of a large new predatory species in half-a-billion-year-old rocks from Kootenay National Park in the Canadian Rockies.

Hydrogen-natural gas hydrates harvested by natural gas
A recent study has suggested a new strategy for stably storing hydrogen, using natural gas as a stabilizer.

Read More: Shale Gas News and Shale Gas Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to