Effects Of Sodium Compounds On Nitrogen Oxides And Mercury Releasing During Coal Combustion

With the rapid development of society, a lot of energy use is inevitable, especially fossil fuels and other primary energy sources, a large number of primary energy exploitation to the environment caused serious pollution and destruction, while the health impact of human survival. In China the major primary energy is coal, due to China’s energy structure, coal as the main energy of the status quo will continue for a very long time. Thermal power plants are the main consumers of coal, thus becoming one of the main sources of emissions of major pollutants which included NOX, CO2, SO2, particulate matter and heavy metals Hg, these hazardous substances to human health and the natural environment had a great impact. The nitrogen oxides NOx and heavy metals Hg harm caused widespread concern. NOx will not only affect human health but also lead to serious environmental problems such as acid rain, and Hg deposition would accumulate in the food chain and harm to human health, so take effective control measures to reduce emissions from coal for the two pollutants is an important task of environmental protection. This article is based on two compounds of alkali metals sodium Na2CO3, NaCl Sodium compound as an additive process for coal-fired combined effect of these two pollutants release of reach while reducing emissions of NOx and Hg purposes.In this paper, a tube furnace heap burning stove dropper way and close to the actual situation and then burned two ways to study the combustion of two sodium compounds for NOx and Hg emissions combined effects respectively. Found in a tube furnace experiments alkali metal compound has a certain influence on the combustion characteristics did not, and to not have a catalytic combustion catalytic role, the coal ignition advance about 15 ℃. As for the release of NOx, NOx release would have appeared a small two freshman response NOx in coal combustion process, but behind the small peaks disappeared or decreased after the addition of sodium compounds in the combustion process, and for coal and coal total NOx emissions as compared to two additives have a certain reduction, Na2CO3 there is an optimal addition ratio of 0.5 but no NaCl was found that the optimum addition ratio during the experiment; and both additives Add temperatures are among the best 900 ℃-1000 ℃. As for the release of mercury term process two additives because of different anions release for Hg have some differences change the types of releases of mercury compounds. In dropper furnace experiments studied the impact of proportion with the addition and temperature on the NOx, and tube furnaces of two different coal-like compounds are present optimum addition ratio of 0.5, which may be due to the combustion furnace and tube dropper Different furnace combustion conditions closer to the actual burning natural; and the best NOx reduction temperature changes by about 1300 ℃. Adding an alkali metal compound increases the amount of HgO in the flue gas to help the oxidation of Hg, but reduces the ash content of Hg.