Comparative analysis on pulverized coal combustion preheated by self-sustained purifying burner with coaxial and centrosymmetric air nozzle structures:Purification,combustion and NO_(x)emission characteristics  

作　　者：Kun Su Ziqu Ouyang Hongshuai Wang Hongliang Ding Wenyu Wang Qisi Chen Shuyun Li 

机构地区：[1]State Key Laboratory of Coal Conversion,Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China [2]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Journal of Chemical Engineering》2025年第1期102-113,共12页中国化学工程学报(英文版)

基　　金：Postdoctoral Fellowship Program of CPSF(GZC20232672);CAS Project for Young Scientists in Basic Research(YSBR-028);the Strategic Priority Research Program(XDA29010200)are gratefully acknowledged.

摘　　要：To optimize secondary air nozzle structure in purifying burner,this study focused on the comparison of purification,combustion and NO_(x)emission characteristics of pulverized coal preheated by a 30 kW purifying burner with coaxial and centrosymmetric structures.Centrosymmetric structure shifted the position of main burning region down in high-temperature reduction unit(HTRU),and the number of branches differently influenced the temperature in different regions with this structure.For reductive gas components,CO concentration with centrosymmetric structure was higher compared to coaxial structure,while the differences in H_(2)and CH_(4)concentrations were smaller.Centrosymmetric structure was more disadvantageous to improve physicochemical properties of pulverized coal compared to coaxial structure,and this structure with four branches further deteriorated its properties compared to two branches.In mild combustion unit(MCU),the temperature at top was lower with centrosymmetric structure,while was higher in the rest.Centrosymmetric structure more effectively reduced NO_(x)emission compared to coaxial structure,but with slight sacrifice of combustion efficiency(h).Moreover,both two-branch and four-branch centrosymmetric structures realized ultra-low NO_(x)emission(<50 mg·m^(-3))with high h of over 98.50%,and the former was more advantageous.With this optimal structure,h and NO_(x)emission were 99.25%and 40.42 mg·m^(-3).

关 键 词：Purifying-burning NO_(x)emission Coaxial structure Centrosymmetric structure 

分 类 号：G63[文化科学—教育学]