Air

Flaring and venting

Flaring is the controlled burning of natural gas at a well site or facility; venting is the release of uncombusted natural gas to the atmosphere.

Most flaring and venting involves “solution gas,” the burning or release of natural gas produced along with crude oil and bitumen. Flaring and venting wastes a potential valuable product and emits methane, carbon dioxide and sulphur dioxide. Incomplete combustion during flaring produces emissions of volatile organic compounds (VOCs) near the flare.

Gas is flared or vented if volumes are small or if the distance to gathering systems and gas plants makes recovery uneconomical. For safety, flaring is used to dispose of gas when problems occur at gas plants or when facilities are shut down for maintenance. Gas may also be flared during tests after completion or servicing of a well.

Public concern about these practices focuses on the environmental effects, possible health risks and climate change.

• voluntary action
  In Alberta, where most of Canada’s oil and gas operations are concentrated, the industry has helped to develop strategies to reduce flaring and venting. Since 1994, the industry has participated in the Clean Air Strategic Alliance (CASA), a multi-stakeholder group that deals with air quality issues in the province. In 1998, industry helped develop a CASA framework for reducing and managing flaring and venting in Alberta. This framework included a provincial target to reduce routine flaring of solution gas in 2001 by 25 per cent below 1996 levels.
  
  This framework was reviewed in 2001, and new targets set, as the original targets had already been exceeded. By the end of 2003, a province wide effort by the industry had resulted in a 70 per cent reduction in flaring below 1996 levels. Venting of natural gas was also included and by the end of 2003 a 38 per cent reduction below venting levels in 2000 was reached.
  
  
• gas conservation
  Where economical, solution gas is gathered and piped to natural gas facilities. In some oilfields, solution gas is re-injected underground to maintain reservoir pressure. The Alberta Energy and Utilities Board says that in 2003 about 95.4 per cent of solution gas was conserved or used in some other manner.
  
  
• operational changes
  Changes in procedures and equipment in natural gas operations reduce the need for flaring during “upsets” and maintenance. Some plants have been reconfigured to process gas that does not meet pipeline specifications. Previously, this “non-spec” gas was flared. New well-testing methods also reduce the duration of flaring. If there are nearby pipelines to processing plants, the test gas can be sent to the plant rather than flared.
  
  
• new technology
  New technologies such as small gas-fired mini-turbine generators can produce electricity from gas that would otherwise be flared.
  
  
• research
  Industry sponsors research that boosts operating efficiencies and provides better understanding of environmental impacts. For example, a group of sponsors, including the industry and the Alberta and Canadian governments, participated in a three-year, $3.3-million study to improve the combustion efficiency of flares. The industry also supports the Western Inter-Provincial Scientific Study Association, a $19-million study looking at the possible impacts of solution gas flaring on livestock health in the four western provinces.

Many of the same technological and conservation measures also contribute to lower venting emissions. For example, industry is exploring opportunities to burn solution gas as fuel for small electrical generating units to reduce venting of methane and flare.