Premium
Experimental research on NO emission with coal preheating combustion technology
Author(s) -
Liu Wen,
Ouyang Ziqu,
Na Yongjie,
Cao Xiaoyang,
Zhu Shujun
Publication year - 2020
Publication title -
asia‐pacific journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.348
H-Index - 35
eISSN - 1932-2143
pISSN - 1932-2135
DOI - 10.1002/apj.2444
Subject(s) - combustion , combustor , coal , nozzle , coaxial , coal combustion products , carbon fibers , nuclear engineering , materials science , chemistry , environmental science , waste management , aerospace engineering , composite material , mechanical engineering , engineering , organic chemistry , composite number
Coal preheating combustion technology was adopted to achieve stable combustion and low NO emission of Shenmu semicoke, and an air‐staging method was also used to further reduce NO emission. A series of experiments have been launched on a 30‐kW coal preheating combustion test rig with a coaxial jet triple channel nozzle. In the study, coal preheated characteristics, combustion behavior, and the formation and destruction mechanisms of NO were discussed. Shenmu semicoke could be preheated up to a temperature above 840°C, and stable combustion was easily established; ~63% of the volatile and 59% of carbon were released and converted into coal gas in the self‐preheating burner. Flame images along the axis of the down‐fired combustor were gained, and the images was dark red without obvious flame fronts. The initial generation of NO in the near field of the preheated fuel nozzle exit had impacts on the NO emission, and lower initial NO generation might result in lower NO emission. By decreasing the inner secondary gas (air), increasing the external secondary air and adding CO 2 in the secondary gas, the initial NO could be inhibited effectively, which finally controlled the NO emission. However, the CO emission might increase in turn generally. In the research, the NO X emissions were <180 mg/m 3 (@6% O 2 ) with the lowest <80 mg/m 3 . To achieve an optimal scheme of NO emission and CO emission, some adjustment methods need to be applied synchronously.