Thermal radiation analysis of an oil well gas flare

Abstract

Paper presented at the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Turkey, 19-21 July, 2010.

Gas flaring, a long-established but unacceptable practice in the Nigerian Petroleum industry, has deleterious effects on the environment. Generally, empirical formulae are employed to estimate thermal radiation fluxes around a gas flare. Thermal radiation field data on Nigerian oil field associated gas flares are rare to come by, thus restricting information on such fields to what can be obtained from existing empirical formulae which are based on data from foreign oil fields. Even then such methods are unable to provide local information on a point-by­ point basis. In this work, the governing equations have been solved numerically yielding local information on the thermal radiation field. The gas flare was considered as a three dimensional turbulent jet issuing into a continuous cross flow of air. The momentum and scalar fluxes were approximated by the k-E turbulence model and the resultant conservation equations were solved using the finite volume technique. The laminar flamelet concept was used to characterize the local thermochemical state of the combusting mixture, while the discrete transfer method was used to compute the radiative heat flux. A model for an accurate prediction of the heat flux at any point in the thermal radiation field around a gas flare was developed. This model has superior prediction capabilities to existing empirical formulae. Safe distances could be deduced from the heat flux field around the flare for both humans and habitat using the model.