Study On Isothermal Combustion Characteristics Of Coal And Release Characteristics Of NOx At O₂/CO₂ Atmosphere

Coal was an important fossil energy.,which has played a significant role in the structure of human energy for a long time.According to the current condition,the main position of coal in C hinese energy consumption would not change a lot in recent years.In the process of coal production and coal combustion,as a result,it has polluted the environment,especially pollutants such as SO₂ and NOx during coal combustion will cause environmental problems,i.e,which could happen acid rain and photochemical smog,etc.Hence.In order to make use of coal resources more efficient ly and environmentally,it was profound significance to research the characteristics of coal combustion and pollutant emission.Firstly,combustion dynamics o f pulverized coal in O₂/CO₂ atmosphere was measured by using isothermal system.And a novel method based on parameters of coal quality was proposed to represent the characteristics of combustion characteristics.Refered the judgement parameter of coal properties FZ as a intergreted express of coal properties parameter,at the same time,defined judgement parameter of combustion D1、D2、S as the quantity reflection of combustion characteristics.Searching the connection of D1、D2、S to FZ under different working condition.Resultly,FZ can cover the main coal properties parameter,D1 、 D2、S can express the combustion characteristics.When temperature and oxygen concentration raised,the slope of D1、D2、S to FZ can accurately reflect the effect degree of coal properties to combustion characteristics.Finally,this paper analysied the influence law of coal difference to combustion characteristics under different condition by constant thermogravimetric equipment and new judgement method,then proving the reliability of the new judgement method.Then,the coke and pulverized coal were carried out at different temperature and reaction atmosphere to research the NOx release characteristic NO x release characteristic curves and NOx release amount were compared during the coke and coal combustion,so that NOx release rules could be obtained.The results showed that the release time was shorten for NOx,the release rate of NO was increased and the release amount of NO 2 was reduce by raising temperature in O₂/CO₂ atmosphere.And the results explained and verified by the conversion rate and kinetic parameters of the reaction further.The instantaneous release amount of NO was raised with O 2 concentration,and it will also promote the oxidation of NO to NO₂;the addition of water vapor made CO₂ and H2 O happen synergistic gasification,and it make the steam gasification more complex,some water vapor could help to stimulate the release of NO₂ and NO;the instantaneous release amount of NO in air was higher than that in O₂/CO₂ atmosphere,but the difference of release characteristics of NO₂ was a little.