| Story Views | |
| Now: | |
| Last Hour: | |
| Last 24 Hours: | |
| Total: | |
Cleaner Fracking
Melody M. Bomgardner, C&EN senior business editor, explains that hydraulic fracturing, or fracking, uses a mixture of water and chemicals injected into the ground to break open rock and release natural gas. Some of that water comes back out of the ground, laden with various salts, minerals, heavy metals and other substances that pose health and environmental risks. The article describes how water treatment firms are responding to that challenge, developing new ways to treat fracking wastewater and competing for business.
Some companies have developed chemical treatments to remove contaminants and microbes from the wastewater, which can then be reused, while others use evaporators to separate fresh water from the brine. Bomgardner notes that treating the wastewater is a special challenge in the Marcellus Shale area of the Appalachian Basin, where wastewater — millions of gallons per well — must be trucked away for disposal. The cost of disposal is spurring oil and gas companies to adopt these and other technologies that could limit the amount of contaminated water that reaches people, plants and animals, the article notes.
Hydraulic fracturing is the propagation of fractures in a rock layer, as a result of the action of a pressurized fluid. Some hydraulic fractures form naturally—certain veins or dikes are examples—and can create conduits along which gas and petroleum from source rocks may migrate to reservoir rocks. Induced hydraulic fracturing or hydrofracking, commonly known as fraccing or fracking, is a technique used to release petroleum, natural gas (including shale gas, tight gas and coal seam gas), or other substances for extraction. This type of fracturing creates fractures from a wellbore drilled into reservoir rock formations.
The first use of hydraulic fracturing was in 1947 but the modern fracking technique, called horizontal slickwater fracking, that made the extraction of shale gas economical was first used in 1998 in the Barnett Shale in Texas. The energy from the injection of a highly pressurized fracking fluid creates new channels in the rock, which can increase the extraction rates and ultimate recovery of hydrocarbons.
Proponents of fracking point to the economic benefits from vast amounts of formerly inaccessible hydrocarbons the process can extract. Opponents point to potential environmental impacts, including contamination of ground water, risks to air quality, the migration of gases and hydraulic fracturing chemicals to the surface, surface contamination from spills and flowback and the health effects of these. For these reasons hydraulic fracturing has come under scrutiny internationally, with some countries suspending or even banning it.
