A gas flare – also known as a flare stack – is a gas combustion device used in industrial plants such as petroleum refineries, chemical plants, and natural gas processing plants and at oil or gas production sites. The flame at the top of an oil rig is an iconic image for the Oil & Gas Industry, yet few people understand why companies choose to burn natural gas.
Flaring for safety
By burning excess natural gas, flaring protects against the dangers of over-pressuring industrial equipment. Natural gas can be stored and transported instead of flared, but it is highly flammable.
Between 2008 and 2012, there were 370 significant safety incidents at natural gas transmission pipelines. These incidents led to 10 fatalities and 85 injuries. Transporting natural gas from a rig to homes and businesses is high risk and many companies choose flaring as the alternative.
Flaring for disposal
One of the main reasons for gas flaring is the disposal and burning of natural gas as waste. Typically when there are large volumes of hydrogen sulfide in natural gas, it cannot be safely extracted. To dispose of this gas, it is burned off. When the gas is burned, the hydrogen is converted into water and the sulphur becomes sulphur dioxide.
Flaring for remote locations
When petroleum crude oil is extracted and produced from onshore or offshore oil wells, natural gas associated with the oil is also brought to the surface. If companies do not have the infrastructure in place to capture natural gas and safely transport it – such as when oil rigs are in deep waters – natural gas is often flared.
Flaring for economics
There is a significant gap between oil and natural gas prices. Natural gas costs more than oil to produce on an energy-equivalent basis. For this reason drillers are searching for oil, not gas, and companies are reluctant to invest in costly projects to capture and transport natural gas from oil wells to the market.