Shale Gas Fracking Causing Friction in the UK

by Dominique Curtis

Controversy in the UK community has sparked over shale gas. Whitmarsh (2015) discusses how shale gas is the newest project the UK government has suggested to help reduce their reliance on energy ports. The community has questioned the UK’s method of fracking to extract the shale gas because fracking is known to use large amounts of water and the chemicals used in the process are toxic. Researchers and the UK government have tried to explain the great benefits that shale gas will have on the economy and the environment while attempting to pacify the communities’ concerns. Environmental groups still protested about how fracking will contaminate and decrease the availability of water supply, and cause erosion and changes in the temperature of the water in aquatic habitats. Continue reading

How Well Does CO2 Adsorb onto Shale?

by Emil Morhardt

If one of the big advantages of using supercritical CO2 rather than water for fracturing shale is that it effectively disposes of the CO2 by absorption onto the shale (Middleton et al. 2013—see Jan 13 post), some experimental evidence would be useful. This is provided by Lafortune et al. (2014) who obtained a sample of shale from a Mesozoic marine basin in France, dried and crushed it, put it on an ultrasensitive balance, and flooded it with CO2 at various pressures and temperatures. The highest pressure was 9 MPa (90 bar, or 90 times atmospheric sea level pressure) and the highest temperature 328 K (131ºF), just at the combination of temperature and pressure at which CO2 becomes supercritical (see figure). This is only about a tenth of the pressure sometimes achieved in actual hydraulic fracking, and probably a somewhat lower temperature than normally used, but might be all that is necessary when using supercritical CO2. The higher the temperature the less CO2 adsorbed onto the shale so that the observation by Middleton et al. that temperatures of supercritical CO2 drop suddenly at the shale when the pressure is released augur well for increasing CO2 adsorption. There was a nearly linear increase in the amount of CO2 adsorption onto the shale with pressure, with no sign of leveling off at the pressures these experimenters used, so that too suggests an effective means of both sequestering CO2 and releasing methane, although the adsorption was not as high as it would have been on coal, someplace else it might be profitably sequestered. Continue reading

Using Supercritical CO2 Instead of Water for Fracking

by Emil Morhardt

The purpose of hydraulic fracturing is to use high pressure to open up pores in deep fuel-bearing shale deposits so that the oil or natural gas can escape through boreholes to the surface. To make this work, very high pressures (hence, much surface equipment) and a great deal of water are required. To keep the pores propped open when the pressure and water recede, something (usually sand) needs to be included. The inclusion of acid can increase pore efficiency, and because water is a good biological medium, antibacterial agents may be required to prevent fouling. Finally, most of the fracking fluid returns to the surface where it presents a treatment and disposal problem. But in theory, any liquid, or supercritical substance, would work, supercritical CO2, for example. According to a study underway at Los Alamos National Laboratory (Middleton et al. 2014) sCO2 has a number of potential advantages over water, and some potential disadvantages as well. Continue reading

Shale Gas Development Poses Threats to Regional Biodiversity

by Shannon Julius

Shale gas development physically and chemically alters the surrounding landscape, and native plants and animals can be particularly susceptible to these changes. In the Marcellus and Utica shale region—a largely forested area that encompasses the states of Pennsylvania, Ohio, and West Virginia—shale gas wells are being drilled with increasing density. A shale gas installation, including the well pad, compressor station, and storage areas, requires 3.56 ha on average. If an edge effect is considered, installations can affect approximately 15 ha of forest per site. Kiviat (2013) reviewed the potential ways that shale gas development can impact biodiversity. The most serious threats are physical alteration of terrestrial landscapes, chemical contamination of water and soil, and alteration of regional hydrology. Terrestrial alterations include construction of well installations, which cause deforestation and habitat loss, and construction of roads and pipelines, which create forest fragmentation. Chemical contaminants come from fracturing fluid and recovered wastewater. Hydrologic alterations are caused by water withdrawals and an increase in impermeable surfaces. Minor impacts on plant and animal health can come from noise, light, and air quality. Certain species are particularly at risk from shale gas development activities and some are able to thrive in the altered conditions. Continue reading

The Fracking Fallacy

by Emil Morhardt

The December 4, 2014 issue of the scientific journal Nature takes the position that the current abundance of natural gas in the US derived from horizontal drilling and hydraulic fracturing may be a much shorter-term phenomenon than most analysts have thought. In both an editorial and an opinion piece (not however in a scientific paper) the journal takes issue with the US Energy Administration’s (USEA) assessment that natural gas production in the US will continue to grow for a quarter century, at least. Nature relies on the opinions of a team of researchers at the University of Texas, and cites a 2013 paper (Patzek, 2012)) by members of the team which now consists of a dozen geoscientists, petroleum engineers, and economists. That paper examines extraction data from 2,057 such wells in the oldest US shale play, the Barnett Shale in Texas, and concludes that they started to decline at an exponential rate in ten years or less, and goes on to predict the total amount of gas that will be produced by their overall sample of 8,294 wells; 10–20 trillion standard cubic feet over the next 50 years. Continue reading

Fracking: Fix it or Forget It? Global Gas and Oil Prices Falling.

by Emil Morhardt

Daniel E. Klein, an energy industry consultant, writes an interesting piece about fracking problems in Natural Gas & Electricity, an industry newsletter. His approach is to look at the prognostications of the Energy Information Administration Annual Energy Outlook (AEO)—pretty much the bible of energy projections—as they have changed from 2000 to projections of where we will stand in 2040. For example, there wasn’t much shale gas until 2005 and in 2005 the AEO predicted that US natural gas imports would increase sharply in the near future. The 2014 projection, however shows the opposite: a steady increase in US exports, at least through 2024. Similarly, “peak oil” in the US has also been reversed by shale oil production, with the crude oil production in 2013 the highest in 25 years, and imports falling sharply, at least so far. Yesterday, the news was that OPEC was debating, on the one hand, decreasing oil production, so as to increase global oil prices and therefore revenues (four members wanted that), or letting production stand so as to lower prices even further to put price pressure on American fracking operations. The latter option won, at least until June when OPEC meets again, but in the short term oil prices will have little effect on American oil operations. Continue reading

Shale Gas Well Drilling and Wastewater Treatment Impacts on Surface Water Quality in Pennsylvania

by Shannon Julius

Shale gas development can affect surface water quality by means of runoff from well construction and discharge from wastewater treatment facilities. Olmstead et al. (2013) conducted a large-scale statistical study of the extent to which these two activities affect surface water quality downstream. This study is different than most current literature related to the regional water impacts of shale gas development in that it focuses on impacts to surface water bodies as opposed to groundwater bodies. Researchers consulted online databases to retrieve locations of shale gas wells and wastewater treatment facilities within Pennsylvania. These were spatially related to downstream water quality monitors using Geographic Information Systems (GIS). Concentrations of chloride (Cl–) and total suspended solids (TSS) were used as indicators of water quality because both are associated with shale gas development and are measured by water quality monitors. Shale gas wastewater typically has a high concentration of Cl–, which can directly damage aquatic ecosystems and is not easily removed once dissolved in water. TSS, which harm water quality by increasing temperature and reducing clarity, can potentially come from the construction of well pads, pipelines, and roads associated with well drilling, especially when precipitation creates sediment runoff. Results of the study suggest that wastewater treatment facilities are responsible for raised concentrations of Cl– downstream and that the presence of gas wells are correlated with raised concentrations of TSS downstream. Continue reading

Marcellus Shale Gas Wastewater Management

by Shannon Julius

Since 2008, the Marcellus shale formation has become the most productive region for extracting shale gas in the US. Managing wastewater for these operations is a challenge not only due to their size and distribution, but also because of the different types of contaminants that are present in various types of wastewater. Rahm et al. (2013) retrieved data from the Pennsylvania Department of Environmental Protection (PADEP) Oil and Gas Reporting website from 2008 to 2011 to look for the trends and drivers of Marcellus shale wastewater management. After analysis using internet resources and Geographic Information Systems (GIS), the authors found that there was a statewide shift towards wastewater reuse and injection disposal treatment methods and away from publicly owned treatment works (POTW) use. These wastewater management trends are likely due to new regulations and policies, media and public scrutiny, and natural gas prices. Research also shows that Marcellus shale development has influenced conventional gas wastewater practices and led to more efficient wastewater transportation. Continue reading

Why Fracking Works

by Emil Morhardt

We hear a great deal about the economic benefits of hydraulic fracturing, and even more about its potential liabilities, but seldom very much about exactly how fracking works. A fascinating new paper just published by the American Society of Mechanical Engineers (Bazant et al. 2014) combines an extremely clear explanation of the process in non-technical language with a detailed mathematical analysis of the mechanics involved (a combination uncommon in engineering papers). The question at hand is why, with pipes just three-inches in diameter, spaced half a kilometer apart, it is possible to get so much gas out of shale beds. The first thing to know is that even this technology gets only about
5–15% of the gas embedded in the shale, so it’s likely they’ll be going back for more as the technology improves. They know about this percentage because of how much gas they can extract from the rock samples they get out of the well cores. Continue reading