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臺灣能源期刊論文全文

臺灣能源期刊第8卷第1期內容

出刊日期:March, 2021

題目
粉煤鍋爐富氧燃燒特性與氮氧化物生成之數值分析
Title
Numerical Analysis of Oxy-fuel Combustion and NOx Formation in a Pulverized-coal Boiler
作者
陳銘宏
Authors
Ming-Hong Chen
摘要
本研究以數值分析方式探討於粉煤鍋爐中進行富氧燃燒程序之現象以及氮氧化物生成評估。所 建立之模式主要包括紊流、輻射以及燃燒模式。本模型先經計算網格獨立測試與實驗結果驗證,確 立其可靠性後,再進行相關參數分析。比較空氣燃燒與富氧燃燒情況之結果中顯示,富氧燃燒情況 將導致相似之溫度分佈、較低之壁面熱傳量、較低之速度與較長之滯留時間。氮氧化物生成評估結 果顯示,富氧燃燒條件乃是有效降低粉煤鍋爐氮氧化物生成量之方法。結果亦顯示,在從空氣燃燒 切換至富氧燃燒的過程中,藉由適當地改變進料條件,可以維持相似之鍋爐溫度分布。
關鍵字
數值分析,富氧燃燒,粉煤鍋爐
Abatract
In the present study, the effect of the oxy-fuel combustion technique on the pulverized-coal boiler and NOx formation is investigated by the proposed numerical model. The turbulence model, radiation model and combustion model are developed in the present study. Grid independent test and comparison with experimental results are conducted to validate the proposed numerical model. The air-firing and oxy-fuel conditions are calculated and compared. The results show that the oxy-fuel combustion leads to similar temperature distribution, lower wall heat flux, smaller flow velocity and longer resident time. NOx evaluation indicates that the oxy-fuel condition is an effective way to reduce the amount of NOx formation for the PC boiler. The results also indicate that similar thermo-conditions could be obtained by carefully manipulating the feeding conditions when switching from air-firing to oxy-fuel combustion.
Keywords
Numerical analysis, Oxy-fuel combustion, Pulverized-coal boiler