Abstract: In order to solve the unstable combustion process of natural gas combustion furnace due to increase of nitrogen content in natural gas caused by the injection of nitrogen in Tahe Oilfield, based on the numerical simulation software Fluent, which is for the tower-linked natural gas containing nitrogen in the furnace conical combustion chamber, the distribution law of temperature field and the formation law of combustion product NO_x are researched in this paper. According to the particularity of the natural gas component of the nitrogen of the tower, the combustion efficiency, NO_x content, ignition temperature and heating value and Webbo index used as the benchmark for the blending scheme, four blending schemes are calculated and compared. A nitrogen-containing natural gas blending scheme based on NO_x content, which will ensure the combustion efficiency, ignition temperature and calorific value and Webbo index of the tower-linked natural gas containing nitrogen is selected. At the same time, this scheme will effectively reduce the environmental pollution caused by nitrogen oxides, and has strong practical significance.