Gas venting
Gas venting, more specifically known as natural-gas venting or methane venting, is the intentional and controlled release of gases containing alkane hydrocarbons - predominately methane - into Earth's atmosphere. It is a widely used method for disposal of unwanted gases which are produced during the extraction of coal and crude oil. Such gases may lack value when they are not recyclable into the production process, have no export route to consumer markets, or are surplus to near-term demand. In cases where the gases have value to the producer, substantial amounts may also be vented from the equipment used for gas collection, transport, and distribution.
Gas venting contributes strongly to climate change.[1][2] Nevertheless, many individual cases are sufficiently small and dispersed to be deemed "safe" with regard to immediate health hazards.
Large and concentrated releases are usually abated with gas flares to produce relatively less-harmful carbon dioxide gas.
Gas venting and flaring that are performed as routine practices are especially wasteful and may be eliminated in many modern industrial operations, where other low-cost options are available to utilize the gas.[3]
Gas venting is not to be confused with similar types of gas release, such as those from:
Gas venting should also not be confused with "gas seepage" from the earth or oceans - either natural or due to human activity.
Associated petroleum and coal mining gases were sometimes considered troublesome, dangerous, low value: a "free" by-product associated with financially more lucrative coal or liquid hydrocarbon recovery that had to be dealt with. The growth of international gas markets, infrastructure and supply chains have done much to change this. It is also becoming more of a standard practice to:
Today, it is financially viable to develop even relatively small hydrocarbon reservoirs containing non-associated gas (i.e. with little or no oil) close to a market or export route, as well as large, remote accumulations.
Fossil gas was recently promoted by some industry advocates and policy makers as a "bridge fuel" that could yield the least waste, and thus environmental damage and accompanying economic losses, during the transition from finite fossil-fuel reserves to more sustainable sources.[18] However, the actual volumes of methane released cumulatively over the supply chain have a near-term climate warming impact which already rivals, and may grow to exceed, that from using coal and oil.[19]