Experimental Studies Of The Flames Structure And The Characteristics Of Pollutant Emissions In ODPP/OESC Swirl Flames

In a long period of time,China's energy demands will continue to grow."The Eighteenth National Congress of the CPC" reports: "Focus on promoting the development of green,recycling and low-carbon development".The newly revised national "boiler air pollutant emission standards" is known as "the history of the most stringent ",which shows that the study of low NOx combustion technology is one of the most important tasks in today's science.This paper,by constructing the three-dimensional swirl experimental system and combustion chamber,analyzes and contrasts with the premixed combustion,partially premixed combustion and oxygen-diluted partially premixed combustion/oxygen-enriched supplemental combustion three kinds of combustion's flame structure,flame temperature,and the way of pollutants.As compared with the former two,on the premise of guarantee the combustion efficiency,ODPP/OESC can effectively reduce the power of flame temperature,thus inhibiting the production of thermal NO_X.This paper mainly analyzes that ODPP/OESC is effective in both the low emission of NO_X and CO through modulation space C/O concentration distribution in the combustion process.We can get the following conclusions:(1)as part of the increase of the fuel-side equivalence ratio,flame structure is improved;the flame temperature distribution is in homogeneous with significant reduction of NO_X generation and slightly increasing of CO;(2)as the total equivalence ratio increasing,the burning of ODPP/OESC is more fully;the release of heat increases,making increased NO_X and reduced CO;(3)the reduction of oxygen diluted concentration,significantly lowers NO_X emissions and makes CO more;(4)the reduced oxygen enriched concentration,reduces NO_X and makes CO slightly increased,but the change of NO_X is more obvious.In the process of debugging,through minimizing oxygen concentration continuously,it is observed that the "turning point" of sharply rising of CO emissions with the reduction of NOx.Near that point,there exists the operation condition range of NO_X emissions which are lower than 50 mg/m3,and the CO emissions below 80 ppm,which validates that ODPP/OESC can consider the low emissions of NO_X and CO.In addition,with the increase of heat release in combustion chamber,it can decrease the temperature of flame,leading to the reduced generation of NO_X and the more generation of CO.In conclusion,by reasonably modulating and distributing the ODPP/OESC swirl combustion of carbon/oxygen concentration distribution in space,it can be concluded that suitable working condition of low emissions.Scope of optimum condition: the total equivalent ratio of 0.8 ~ 0.9,part of the premixed equivalent ratio of 1.1 ~ 1.2,oxygen content of dilute oxygen concentration of 18% ~ 20%.This range can modulate multiple sets of NO_X which is lower than 50 mg/m3 and the operation condition of the CO emissions below 80 ppm.Through the study,with the increase of rich oxygen concentration,NO_X generation increases.So on the basis of the concentration of oxygen-enriched according to air discount,the oxygen enriched can be added to the right amount of nitrogen in order to reduce the concentration of oxygen enrichment,keeping within 25% oxygen.