一氧化碳鍋爐三維燃燒流場解析

Three-dimensional Analysis of the Combustion and Fluid Flow in a Carbon Monoxide Boiler

簡國財(Guo-Tsai Jian)

指導教授 ： 葉俊郎

國立虎尾科技大學/工程學院/航空與電子科技研究所/碩士(2012年)

https://doi.org/10.6827/NFU.2012.00016

摘要

一氧化碳鍋爐在煉油製程中佔有非常重要的角色，它可以將再生器中的一氧化碳(CO)熱能回收再利用，所產生的蒸汽可提供給其他設備使用，其操作溫度相當高（可達1200℃），因此，會產生一氧化碳鍋爐內外部問題，其停車檢查維修所造成之生產損失每日以千萬元起計，而其所潛藏的工安與環保問題更是不容忽視，因此，本研究即在此背景下針對一氧化碳鍋爐的三維燃燒流場進行詳細探討，本文以增厚耐火泥、裝設導流錐、過剩空氣流量調整以及煙道氣流量調整對於一氧化碳鍋爐燃燒流場以及氮氧化物（NOx）生成之影響作為主要探討對象。
由研究結果得知增厚耐火泥除了有助於降低脫硝段溫度與摩擦力之外，亦有助於降低脫硝段NOx生成量；裝設導流錐有助於降低脫硝段溫度與脫硝段NOx生成量；當增加空氣流量或減少煙道氣流量時均有助於降低脫硝段溫度，而減少空氣流量或煙道氣流量均有助於降低脫硝段摩擦力，減少空氣流量或增加煙道氣流量均有助於降低NOx生成量與CO的含量。

關鍵字

一氧化碳鍋爐 ； 耐火泥 ； 導流錐 ； 三維燃燒流場 ； 脫硝

並列摘要

Carbon Monoxide (CO) boiler plays an important role in the oil refinery process. It can retrieve the thermal energy of CO from the regenerator for application. CO boiler utilizes the burning gas (CO) from the regenerator as fuel. Then CO reacts form CO2 and release large amount of heat. The hot flue gas then flows through the superheater section and exchanges heat with water in the tubes to produce superheated steam which can be used by other equipments. The operating temperatures in a CO boiler can be as high as 1200℃. This can lead to the interior or exterior problems of a CO boiler. The loss caused by product loss of a CO boiler can be as high as one million US$ per day. Furthermore, the potential threats of safety and environment protection can not be ignored. In this study, the influences of refractory thickness, guide cone angle, inlet air flow rate and flue gas flow rate on the combustion and fluid flow as well as NOx formation in a CO boiler are discussed.
From the simulation results, it is found that refractory thickening can reduce the temperature and the skin friction in the DeNOx section. Furthermore, the NOx formation is also alleviated by refractory thickening. Installation of a guide cone can reduce the temperature, the skin friction and the NOx formation in the DeNOx section. With higher air flow rate and lower flue gas flow rate, the temperature in the DeNOx section can be reduced. On the other hand, with lower air flow rate and flue gas flow rate, the skin friction in the DeNOx section can be reduced. Finally, with lower air flow rate and higher flue gas flow rate, the NOx formation and CO concentration can be alleviated.

並列關鍵字

CO boiler ； Refractory ； Guide Cone ； Combustion ； NOx reduction

參考文獻

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