The Study On The Low NOx Whirl Combustor Of Burning Inferior Coal

NO_x from coal burning is the important source of the atmosphere pollution, and NO_x control techniques are studied. Compared to all the methords, low NO_x combustor has very good competitive advantages from technical maturity, out-efficiency of reducing NO_x, and overall costs and the transformation of the latter part of the operation costs . Most of the power coal used in China is inferior coal, and the NO_x reduction of the inferior coal is difficult, and inferior coal is not easy to burn steadily. Therefore it is necessary to develop a low NO_x combustor based on the inferior coal, and it has project value.First the cold condition experiment on an archetypal combustor was carried out.Three vector velocities of the plumb surface was measured, Then the hot condition experiment was carried out on a horizontal single-furnace system. Fourier Transform Infrared Spectroscopy (FTIR)was used to quantify NO, CO, HCN, CH₄, CO₂, O₂ . The results show that the center air has more effects on the back flow field, and the inter-second air is minor , outer-second air is least, it could be ignored. The size of the back flow field influence the release of NO and the temperature in the furnace.Then LN-B ameliorated swirl combustor was developed based on the archetypal combustor's cold and hot experiments. The second air includes rotational flow inter-second air, rotational flow medium-second air and the direct flow outer-second air. The center air is only to be used as the oil air. The hot condition experiment of LN-B ameliorated swirl combustor was also carried out on the horizontal single-furnace system. Compared to the experiments of the archetypal combustor, the results showed that NO reducing rates were respectively improved by 62.8% and 66.4% with the lean coal and bovey coa. The lean coal flame center of the LN-B ameliorated swirl combustor is aheader , and it can stably burn with the low temperature.