Production
In mines, where methane seeping from rock formations has no odor, sensors are used, and mining apparatus such as the Davy lamp has been specifically developed to avoid ignition sources.
Some gas fields yield sour gas containing hydrogen sulfide (H2S). This untreated gas is toxic. Amine gas treating, an industrial scale process which removes acidic gaseous components, is often used to remove hydrogen sulfide from natural gas.
Extraction of natural gas (or oil) leads to decrease in pressure in the reservoir. Such decrease in pressure in turn may result in subsidence, sinking of the ground above. Subsidence may affect ecosystems, waterways, sewer and water supply systems, foundations, and so on.
Another ecosystem effect results from the noise of the process. This can change the composition of animal life in the area, and have consequences for plants as well in that animals disperse seeds and pollen.
Releasing the gas from low-permeability reservoirs is accomplished by a process called hydraulic fracturing or "hydrofracking". To allow the natural gas to flow out of the shale, oil operators force 1 to 9 million US gallons (34,000 m3) of water mixed with a variety of chemicals through the wellbore casing into the shale. The high pressure water breaks up or "fracks" the shale, which releases the trapped gas. Sand is added to the water as a proppant to keep the fractures in the shale open, thus enabling the gas to flow into the casing and then to the surface. The chemicals are added to the frack fluid to reduce friction and combat corrosion. During the extracting life of a gas well, other low concentrations of other chemical substances may be used, such as biocides to eliminate fouling, scale and corrosion inhibitors, oxygen scavengers to remove a source of corrosion, and acids to clean the perforations in the pipe.
Dealing with fracking fluid can be a challenge. Along with the gas, 30 per cent to 70 per cent of the chemically laced frack fluid, or flow back, returns to the surface. Additionally, a significant amount of salt and other minerals, once a part of the rock layers that were under prehistoric seas, may be incorporated in the flow back as they dissolve in the frack fluid.
Read more about this topic: Natural Gas, Safety Concerns
Famous quotes containing the word production:
“The growing of food and the growing of children are both vital to the family’s survival.... Who would dare make the judgment that holding your youngest baby on your lap is less important than weeding a few more yards in the maize field? Yet this is the judgment our society makes constantly. Production of autos, canned soup, advertising copy is important. Housework—cleaning, feeding, and caring—is unimportant.”
—Debbie Taylor (20th century)
“The production of too many useful things results in too many useless people.”
—Karl Marx (1818–1883)
“It is part of the educator’s responsibility to see equally to two things: First, that the problem grows out of the conditions of the experience being had in the present, and that it is within the range of the capacity of students; and, secondly, that it is such that it arouses in the learner an active quest for information and for production of new ideas. The new facts and new ideas thus obtained become the ground for further experiences in which new problems are presented.”
—John Dewey (1859–1952)