Detailed multi-dimensional study on NOx formation and destruction mechanisms in dimethyl ether/air diffusion flame under the moderate or intense low-oxygen dilution (MILD) condition. (15th January 2017)

• Record Type: Journal Article
• Authors: Kang, Yinhu; Wei, Shuang; Zhang, Pengyuan; Lu, Xiaofeng; Wang, Quanhai; Gou, Xiaolong; Huang, Xiaomei; Peng, Shini; Yang, Dong; Ji, Xuanyu
• Is Part Of: Energy. Volume 119(2017)
• Page Start: 1195
• Page End: 1211
• Publication Date: 2017-01-15
• Subjects: Dimethyl ether -- Moderate or intense low-oxygen dilution -- NOx mechanism -- Reaction path analysis -- Sensitivity analysis; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2016.11.070
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: In this paper, the moderate or intense low-oxygen dilution (MILD) technology was employed to reduce NO x emission index of the DME flame, whose NO x emission was expected high due to its higher adiabatic flame temperature. Experiments and modeling were conducted to study NO x emission mechanism of the DME-MILD jet diffusion flame. Various co-flow temperatures ( T c o ∗ ) and oxygen concentrations ( X O 2 ∗ ) were involved to investigate dependence of NO x emission mechanism on hot dilution level. NO x formation pathway in all subzones was clarified, employing the reaction path and sensitivity analyses. The results showed that for the DME-MILD jet flame, NO x was generated mainly through the NNH and N2 O pathways, which was rather different from the traditional DME jet diffusion flame. EI NOx increased gradually with the increment in X O 2 ∗ or T c o ∗ . A strong NONO2 conversion process and ultra-clean performance were verified for the DME-MILD jet flame. Highlights: A coaxial jet burner with hot diluted co-flow was used to model the MILD condition. NO x emission process has been predicted by CFD-CRN method with detailed kinetics. NO x of DME-MILD flame was generated mainly via N2 O- and NNH-intermediate pathways. NO x emission decreased with increase in co-flow temperature or oxygen concentration. Ultra-clean performance of the DME-MILD flame has been validated.