高含氮料源於渦旋式流體化床燃燒爐中燃燒之研究

A Study of High Nitrogen Content Feedstock Combustion in a Vortexing Fluidized Bed Combustor

溫佳叡(Jia-Ruei Wen)

指導教授 ： 錢建嵩

中原大學/工學院/化學工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201100831

摘要

中文摘要

本研究係於一實驗室規模之渦旋式流體化床燃燒爐中進行，其乾舷區內徑為0.154公尺，高4公尺，燃燒室截面積為0.22公尺 × 0.11公尺，二次空氣由乾舷區下端以切線方向進入爐內，其注入點位於分配板上方0.796公尺，本研究以氮含量為16.8 wt%之豬皮為燃料，矽砂為床質，利用含氮量高達16.8%之豬皮進行燃燒之研究，探討各操作參數如床溫、床下計量氧比、過量氧率、乾舷區溫度、床高、床質粒徑及旋風分離器對爐出口之CO、NO排放濃度之影響。

研究結果顯示，乾舷區溫度效應對於爐出口之CO影響最為顯著，其次為過量氧率效應；對於NO排放濃度而言，以過量氧率影響最為顯著，其次為床溫效應，再者為乾舷區溫度效應；當實驗操作在乾舷區溫度750℃及800℃時，發現CO排放濃度呈現較高且NO排放濃度較低之現象，同時於實驗中發現當乾舷區溫度在900℃時，NO會有下降之趨勢。旋風分離器對於CO排放有降低效應，尤其是在高CO濃度時，效應更為顯著，對於NO之排放濃度並無顯著效應。

關鍵字

流體化床燃燒 ； 高含氮量 ； 旋風分離器 ； 氮氧化物

並列摘要

Abstract

A bench-scale vortexing fluidized bed combustor (VFBC) was set up in this study. The combustor cross area is 0.22 × 0.11 m2, and the freeboard is in 0.154 m I.D. and 4 m height. The secondary air injected nozzles were installed tangentially at the bottom of freeboard. Pig hide was used as the fuel in this study. Silica sand was employed as the bed material. The effects of various operating parameters, such as bed temperature, stoichiometric oxygen in the combustion chamber the excess oxygen ratio, freeboard temperature, static bed height and the diameter of bed material were investigated. The effects of operating conditions on NO and CO emissions at the cyclone inlet and outlet were also investigated.

The results of CO emissions show that the effect freeboard temperature is more important than the excess oxygen ratio. The results of NO emissions show that the effect of the excess oxygen ratio is more important than the effect of bed temperature, and the effect of stoichiometric oxygen in the combustion chamber is the lowest of the three parameters. The experimental results of the effect of freeboard temperature show that when the freeboard temperature is at 750℃and 800℃, the emissions of NO is low but CO is high and with the increasing of the freeboard temperature the NO concentration will first increase then decrease at 900℃. For the results of CO and NO emissions at the inlet and outlet cyclone, the cyclone has more effect on CO emissions than NO emissions, especially CO emissions is high.

並列關鍵字

fluidized bed combustion ； high nitrogen content ； cyclone

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