Gas Flaring

Gas flaring in offshore installations and oil refineries represents a source of loss of energy making it important to operators and authorities to monitor the amounts of flared gas. In some countries the flare gas is subject to CO2 tax. Flow metering systems are installed on some but not all flare systems. 

Leahey, D.M. and M.J.E. Davies, 1984. Observations of Plume Rise from Sour Gas Flares. Atmospheric Environment, 18, 917-922. Misra, P.K. and S. Onlock, 1982. Modelling Continuous Fumigation of Nanticoke Generating Station Plume. Atmospheric Environment, 16, 479-482. 

Benson NU, Etesin UM (2008) Metal contamination of surface water, sediment and Tympa-notonus fuscatus var. radula of Iko River and environmental impact due to Utapete gas flare station, Nigeria. Environmentalist 28 195... 

Elvidge, C. D. (2007). A Twelve Year Record of National and Global Gas Flaring... 

GAO (United States Government Accountability Office) (2004). Natural Gas Flaring and Venting. Opportunities to Improve Data and Reduce Emissions. Report GAO-04-809. Washington, DC. www.gao.gov/cgi-bin/getrpt7GAO-04-809. 

Gas recovery systems have been installed in some large municipal landfills, with the gas flared used to run spark-ignition diesel engines to generate power for sale to the grid or the gas is cleaned up and piped to nearby users. The economics of such operations must be reviewed for each site. The end use of gas will affect the overall economics. The... 

MarlandG., Andres R. J., Boden T. A., and Johnston C. (1998) Global, Regional and National CO2 Emission Estimates from Fossil Fuel Burning, Cement Production, and Gas Flaring 1751-1995 (revised January 1998). ORNL/CDLAC NDP-030/R8, http //cdiac.esd.ornl.gOv/ndps/ndp030.html... 

Boden, T. A., Marland, G., and Andres, R. J. (1995). Estimates of Global, Regional, and National CO2 Emissions from Fossil-Fuel Burning, Hydraulic Cement Production, and Gas Flaring 1950-1992," ORNL/CDlAC-90, NDP-030/R6. Oak Ridge National Laboratory, Oak Ridge, TN, December. 

To date, eight experimental runs have been conducted. Significant data from two of the runs, RUN 02-wood chips, and RUN 08-solid waste cubes, are shown in Tables I and II. The gas sampling equipment was not in operation for RUN 02, so a gas analysis is not available for that run however, a good quality low-BTU gas was generated as evidenced by the clean burning gas flare. RUN 08, using solid waste cubes, is more completely documented. 

Almost half the amount of pyrolysis gas produced was burnt in the exhaust gas flare the other part was sufficient to support the energy demands of the process, being burnt in the radiation fire tubes. Waste heat from the reactor heating (cooler) was sufficient to heat the distillation column. 

Anon., Almost Unnoticeable Gas Flaring, Proc. Indust. Canada, 73(2), 24, Mar. (1989). 

Fig. 7.5 Global C02 emissions from fossil-fuel burning (solid, liquid and gaseous fuels), cement production and gas flaring for 1751-1999. After Marland et al. (2002).

D. J. "Size and Radiative Characteristics of Natural Gas Flares. Part 1 Field Scale Experiments." Chemical Engineering Research and Design 65, no. 4 (1987) 310-17. 

The advantages of an active gas control system are that the abstraction can be controlled, the reduction of within-waste gas pressure will be more effective than with passive systems, and because in most situations, the collected gas is burned, the atmospheric pollution potential is reduced. Although gas flaring does not remove all trace components and bulk gases, the concentrations of each are significantly reduced. 

For effective utilisation in gas engines or turbines, the methane content of landfill gas should be approximately 50%. However, where gas collection is used primarily for the control of migration and the protection of sensitive targets then the methane content of the gas is often much less than 50% in order to maintain a flame at the gas flare. For this reason, it is important clearly to identify at the outset whether the gas collection system is for gas control or energy generation. Local site conditions may require the use of both types of system where, for instance, peripheral wells are used for gas migration control and central weUs are used for collection with subsequent utilisation for electricity production. It is also possible for wells to be designed and built to accomodate both systems and to be... 

Baldwin, G. and Scott, P.M. (1991) Investigations into the performance of landfill gas flaring systems in the UK. In Sardinia 91, Proc. Third International Symposiwn, Vol 1. Grafiche Galeati, Imola. 301-312... 

Global Gas Flaring Reduction Partnership, World Bank Issue Brief, The World Bank, 2006. 

Due to feed gas reduction to 450 MMSCFD and export to QP and fuel gas system from Unit 04 (total 400 MMSCFD), wet gas flaring from Unit 02 is eliminated and dry gas flaring from Unit 04 reduced from 450 MMSCFD (earlier practice) to 50 MMSCFD. 

Reduction in purge rates to API 521 levels at wet and dry gas flare headers and use of existing steam-assisted tips and stack steam for bumback prevention rather than fuel gas. 

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